1989d42e8SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0 21da177e4SLinus Torvalds /* 31da177e4SLinus Torvalds * drivers/base/core.c - core driver model code (device registration, etc) 41da177e4SLinus Torvalds * 51da177e4SLinus Torvalds * Copyright (c) 2002-3 Patrick Mochel 61da177e4SLinus Torvalds * Copyright (c) 2002-3 Open Source Development Labs 764bb5d2cSGreg Kroah-Hartman * Copyright (c) 2006 Greg Kroah-Hartman <gregkh@suse.de> 864bb5d2cSGreg Kroah-Hartman * Copyright (c) 2006 Novell, Inc. 91da177e4SLinus Torvalds */ 101da177e4SLinus Torvalds 117847a145SHeikki Krogerus #include <linux/acpi.h> 1265650b35SRafael J. Wysocki #include <linux/cpufreq.h> 131da177e4SLinus Torvalds #include <linux/device.h> 141da177e4SLinus Torvalds #include <linux/err.h> 1597badf87SRafael J. Wysocki #include <linux/fwnode.h> 161da177e4SLinus Torvalds #include <linux/init.h> 1773060022SChristophe JAILLET #include <linux/kstrtox.h> 181da177e4SLinus Torvalds #include <linux/module.h> 191da177e4SLinus Torvalds #include <linux/slab.h> 201da177e4SLinus Torvalds #include <linux/string.h> 2123681e47SGreg Kroah-Hartman #include <linux/kdev_t.h> 22116af378SBenjamin Herrenschmidt #include <linux/notifier.h> 2307d57a32SGrant Likely #include <linux/of.h> 2407d57a32SGrant Likely #include <linux/of_device.h> 25322cbb50SChristoph Hellwig #include <linux/blkdev.h> 26f75b1c60SDave Young #include <linux/mutex.h> 27af8db150SPeter Chen #include <linux/pm_runtime.h> 28c4e00daaSKay Sievers #include <linux/netdevice.h> 29174cd4b1SIngo Molnar #include <linux/sched/signal.h> 30b8530017SOliver Neukum #include <linux/sched/mm.h> 3169031f50SClaire Chang #include <linux/swiotlb.h> 3263967685SGreg Kroah-Hartman #include <linux/sysfs.h> 336d4e9a8eSChristoph Hellwig #include <linux/dma-map-ops.h> /* for dma_default_coherent */ 341da177e4SLinus Torvalds 351da177e4SLinus Torvalds #include "base.h" 366423d295SWon Chung #include "physical_location.h" 371da177e4SLinus Torvalds #include "power/power.h" 381da177e4SLinus Torvalds 399ed98953SRafael J. Wysocki /* Device links support. */ 40fc5a251dSSaravana Kannan static LIST_HEAD(deferred_sync); 41fc5a251dSSaravana Kannan static unsigned int defer_sync_state_count = 1; 427b337cb3SSaravana Kannan static DEFINE_MUTEX(fwnode_link_lock); 4325ac86c6SSaravana Kannan static bool fw_devlink_is_permissive(void); 443a2dbc51SSaravana Kannan static void __fw_devlink_link_to_consumers(struct device *dev); 45d46f3e3eSSaravana Kannan static bool fw_devlink_drv_reg_done; 462f8c3ae8SSaravana Kannan static bool fw_devlink_best_effort; 477b337cb3SSaravana Kannan 487b337cb3SSaravana Kannan /** 493a2dbc51SSaravana Kannan * __fwnode_link_add - Create a link between two fwnode_handles. 507b337cb3SSaravana Kannan * @con: Consumer end of the link. 517b337cb3SSaravana Kannan * @sup: Supplier end of the link. 527b337cb3SSaravana Kannan * 537b337cb3SSaravana Kannan * Create a fwnode link between fwnode handles @con and @sup. The fwnode link 547b337cb3SSaravana Kannan * represents the detail that the firmware lists @sup fwnode as supplying a 557b337cb3SSaravana Kannan * resource to @con. 567b337cb3SSaravana Kannan * 577b337cb3SSaravana Kannan * The driver core will use the fwnode link to create a device link between the 587b337cb3SSaravana Kannan * two device objects corresponding to @con and @sup when they are created. The 597b337cb3SSaravana Kannan * driver core will automatically delete the fwnode link between @con and @sup 607b337cb3SSaravana Kannan * after doing that. 617b337cb3SSaravana Kannan * 627b337cb3SSaravana Kannan * Attempts to create duplicate links between the same pair of fwnode handles 637b337cb3SSaravana Kannan * are ignored and there is no reference counting. 647b337cb3SSaravana Kannan */ 653a2dbc51SSaravana Kannan static int __fwnode_link_add(struct fwnode_handle *con, 666a6dfdf8SSaravana Kannan struct fwnode_handle *sup, u8 flags) 677b337cb3SSaravana Kannan { 687b337cb3SSaravana Kannan struct fwnode_link *link; 697b337cb3SSaravana Kannan 707b337cb3SSaravana Kannan list_for_each_entry(link, &sup->consumers, s_hook) 716a6dfdf8SSaravana Kannan if (link->consumer == con) { 726a6dfdf8SSaravana Kannan link->flags |= flags; 733a2dbc51SSaravana Kannan return 0; 746a6dfdf8SSaravana Kannan } 757b337cb3SSaravana Kannan 767b337cb3SSaravana Kannan link = kzalloc(sizeof(*link), GFP_KERNEL); 773a2dbc51SSaravana Kannan if (!link) 783a2dbc51SSaravana Kannan return -ENOMEM; 797b337cb3SSaravana Kannan 807b337cb3SSaravana Kannan link->supplier = sup; 817b337cb3SSaravana Kannan INIT_LIST_HEAD(&link->s_hook); 827b337cb3SSaravana Kannan link->consumer = con; 837b337cb3SSaravana Kannan INIT_LIST_HEAD(&link->c_hook); 846a6dfdf8SSaravana Kannan link->flags = flags; 857b337cb3SSaravana Kannan 867b337cb3SSaravana Kannan list_add(&link->s_hook, &sup->consumers); 877b337cb3SSaravana Kannan list_add(&link->c_hook, &con->suppliers); 880c058fb9SSaravana Kannan pr_debug("%pfwf Linked as a fwnode consumer to %pfwf\n", 89ebd6823aSSaravana Kannan con, sup); 907b337cb3SSaravana Kannan 913a2dbc51SSaravana Kannan return 0; 923a2dbc51SSaravana Kannan } 933a2dbc51SSaravana Kannan 943a2dbc51SSaravana Kannan int fwnode_link_add(struct fwnode_handle *con, struct fwnode_handle *sup) 953a2dbc51SSaravana Kannan { 963a2dbc51SSaravana Kannan int ret; 973a2dbc51SSaravana Kannan 983a2dbc51SSaravana Kannan mutex_lock(&fwnode_link_lock); 996a6dfdf8SSaravana Kannan ret = __fwnode_link_add(con, sup, 0); 1003a2dbc51SSaravana Kannan mutex_unlock(&fwnode_link_lock); 1017b337cb3SSaravana Kannan return ret; 1027b337cb3SSaravana Kannan } 1037b337cb3SSaravana Kannan 1047b337cb3SSaravana Kannan /** 10576f13081SSaravana Kannan * __fwnode_link_del - Delete a link between two fwnode_handles. 10676f13081SSaravana Kannan * @link: the fwnode_link to be deleted 10776f13081SSaravana Kannan * 10876f13081SSaravana Kannan * The fwnode_link_lock needs to be held when this function is called. 10976f13081SSaravana Kannan */ 11076f13081SSaravana Kannan static void __fwnode_link_del(struct fwnode_link *link) 11176f13081SSaravana Kannan { 1120c058fb9SSaravana Kannan pr_debug("%pfwf Dropping the fwnode link to %pfwf\n", 113ebd6823aSSaravana Kannan link->consumer, link->supplier); 11476f13081SSaravana Kannan list_del(&link->s_hook); 11576f13081SSaravana Kannan list_del(&link->c_hook); 11676f13081SSaravana Kannan kfree(link); 11776f13081SSaravana Kannan } 11876f13081SSaravana Kannan 11976f13081SSaravana Kannan /** 1206a6dfdf8SSaravana Kannan * __fwnode_link_cycle - Mark a fwnode link as being part of a cycle. 1216a6dfdf8SSaravana Kannan * @link: the fwnode_link to be marked 1226a6dfdf8SSaravana Kannan * 1236a6dfdf8SSaravana Kannan * The fwnode_link_lock needs to be held when this function is called. 1246a6dfdf8SSaravana Kannan */ 1256a6dfdf8SSaravana Kannan static void __fwnode_link_cycle(struct fwnode_link *link) 1266a6dfdf8SSaravana Kannan { 1276a6dfdf8SSaravana Kannan pr_debug("%pfwf: Relaxing link with %pfwf\n", 1286a6dfdf8SSaravana Kannan link->consumer, link->supplier); 1296a6dfdf8SSaravana Kannan link->flags |= FWLINK_FLAG_CYCLE; 1306a6dfdf8SSaravana Kannan } 1316a6dfdf8SSaravana Kannan 1326a6dfdf8SSaravana Kannan /** 1337b337cb3SSaravana Kannan * fwnode_links_purge_suppliers - Delete all supplier links of fwnode_handle. 1347b337cb3SSaravana Kannan * @fwnode: fwnode whose supplier links need to be deleted 1357b337cb3SSaravana Kannan * 1367b337cb3SSaravana Kannan * Deletes all supplier links connecting directly to @fwnode. 1377b337cb3SSaravana Kannan */ 1387b337cb3SSaravana Kannan static void fwnode_links_purge_suppliers(struct fwnode_handle *fwnode) 1397b337cb3SSaravana Kannan { 1407b337cb3SSaravana Kannan struct fwnode_link *link, *tmp; 1417b337cb3SSaravana Kannan 1427b337cb3SSaravana Kannan mutex_lock(&fwnode_link_lock); 14376f13081SSaravana Kannan list_for_each_entry_safe(link, tmp, &fwnode->suppliers, c_hook) 14476f13081SSaravana Kannan __fwnode_link_del(link); 1457b337cb3SSaravana Kannan mutex_unlock(&fwnode_link_lock); 1467b337cb3SSaravana Kannan } 1477b337cb3SSaravana Kannan 1487b337cb3SSaravana Kannan /** 1497b337cb3SSaravana Kannan * fwnode_links_purge_consumers - Delete all consumer links of fwnode_handle. 1507b337cb3SSaravana Kannan * @fwnode: fwnode whose consumer links need to be deleted 1517b337cb3SSaravana Kannan * 1527b337cb3SSaravana Kannan * Deletes all consumer links connecting directly to @fwnode. 1537b337cb3SSaravana Kannan */ 1547b337cb3SSaravana Kannan static void fwnode_links_purge_consumers(struct fwnode_handle *fwnode) 1557b337cb3SSaravana Kannan { 1567b337cb3SSaravana Kannan struct fwnode_link *link, *tmp; 1577b337cb3SSaravana Kannan 1587b337cb3SSaravana Kannan mutex_lock(&fwnode_link_lock); 15976f13081SSaravana Kannan list_for_each_entry_safe(link, tmp, &fwnode->consumers, s_hook) 16076f13081SSaravana Kannan __fwnode_link_del(link); 1617b337cb3SSaravana Kannan mutex_unlock(&fwnode_link_lock); 1627b337cb3SSaravana Kannan } 1637b337cb3SSaravana Kannan 1647b337cb3SSaravana Kannan /** 1657b337cb3SSaravana Kannan * fwnode_links_purge - Delete all links connected to a fwnode_handle. 1667b337cb3SSaravana Kannan * @fwnode: fwnode whose links needs to be deleted 1677b337cb3SSaravana Kannan * 1687b337cb3SSaravana Kannan * Deletes all links connecting directly to a fwnode. 1697b337cb3SSaravana Kannan */ 1707b337cb3SSaravana Kannan void fwnode_links_purge(struct fwnode_handle *fwnode) 1717b337cb3SSaravana Kannan { 1727b337cb3SSaravana Kannan fwnode_links_purge_suppliers(fwnode); 1737b337cb3SSaravana Kannan fwnode_links_purge_consumers(fwnode); 1747b337cb3SSaravana Kannan } 1759ed98953SRafael J. Wysocki 17628ec344bSSaravana Kannan void fw_devlink_purge_absent_suppliers(struct fwnode_handle *fwnode) 1779528e0d9SSaravana Kannan { 1789528e0d9SSaravana Kannan struct fwnode_handle *child; 1799528e0d9SSaravana Kannan 1809528e0d9SSaravana Kannan /* Don't purge consumer links of an added child */ 1819528e0d9SSaravana Kannan if (fwnode->dev) 1829528e0d9SSaravana Kannan return; 1839528e0d9SSaravana Kannan 1849528e0d9SSaravana Kannan fwnode->flags |= FWNODE_FLAG_NOT_DEVICE; 1859528e0d9SSaravana Kannan fwnode_links_purge_consumers(fwnode); 1869528e0d9SSaravana Kannan 1879528e0d9SSaravana Kannan fwnode_for_each_available_child_node(fwnode, child) 1889528e0d9SSaravana Kannan fw_devlink_purge_absent_suppliers(child); 1899528e0d9SSaravana Kannan } 19028ec344bSSaravana Kannan EXPORT_SYMBOL_GPL(fw_devlink_purge_absent_suppliers); 1919528e0d9SSaravana Kannan 1923a2dbc51SSaravana Kannan /** 1933a2dbc51SSaravana Kannan * __fwnode_links_move_consumers - Move consumer from @from to @to fwnode_handle 1943a2dbc51SSaravana Kannan * @from: move consumers away from this fwnode 1953a2dbc51SSaravana Kannan * @to: move consumers to this fwnode 1963a2dbc51SSaravana Kannan * 1973a2dbc51SSaravana Kannan * Move all consumer links from @from fwnode to @to fwnode. 1983a2dbc51SSaravana Kannan */ 1993a2dbc51SSaravana Kannan static void __fwnode_links_move_consumers(struct fwnode_handle *from, 2003a2dbc51SSaravana Kannan struct fwnode_handle *to) 2013a2dbc51SSaravana Kannan { 2023a2dbc51SSaravana Kannan struct fwnode_link *link, *tmp; 2033a2dbc51SSaravana Kannan 2043a2dbc51SSaravana Kannan list_for_each_entry_safe(link, tmp, &from->consumers, s_hook) { 2056a6dfdf8SSaravana Kannan __fwnode_link_add(link->consumer, to, link->flags); 2063a2dbc51SSaravana Kannan __fwnode_link_del(link); 2073a2dbc51SSaravana Kannan } 2083a2dbc51SSaravana Kannan } 2093a2dbc51SSaravana Kannan 2103a2dbc51SSaravana Kannan /** 2113a2dbc51SSaravana Kannan * __fw_devlink_pickup_dangling_consumers - Pick up dangling consumers 2123a2dbc51SSaravana Kannan * @fwnode: fwnode from which to pick up dangling consumers 2133a2dbc51SSaravana Kannan * @new_sup: fwnode of new supplier 2143a2dbc51SSaravana Kannan * 2153a2dbc51SSaravana Kannan * If the @fwnode has a corresponding struct device and the device supports 2163a2dbc51SSaravana Kannan * probing (that is, added to a bus), then we want to let fw_devlink create 2173a2dbc51SSaravana Kannan * MANAGED device links to this device, so leave @fwnode and its descendant's 2183a2dbc51SSaravana Kannan * fwnode links alone. 2193a2dbc51SSaravana Kannan * 2203a2dbc51SSaravana Kannan * Otherwise, move its consumers to the new supplier @new_sup. 2213a2dbc51SSaravana Kannan */ 2223a2dbc51SSaravana Kannan static void __fw_devlink_pickup_dangling_consumers(struct fwnode_handle *fwnode, 2233a2dbc51SSaravana Kannan struct fwnode_handle *new_sup) 2243a2dbc51SSaravana Kannan { 2253a2dbc51SSaravana Kannan struct fwnode_handle *child; 2263a2dbc51SSaravana Kannan 2273a2dbc51SSaravana Kannan if (fwnode->dev && fwnode->dev->bus) 2283a2dbc51SSaravana Kannan return; 2293a2dbc51SSaravana Kannan 2303a2dbc51SSaravana Kannan fwnode->flags |= FWNODE_FLAG_NOT_DEVICE; 2313a2dbc51SSaravana Kannan __fwnode_links_move_consumers(fwnode, new_sup); 2323a2dbc51SSaravana Kannan 2333a2dbc51SSaravana Kannan fwnode_for_each_available_child_node(fwnode, child) 2343a2dbc51SSaravana Kannan __fw_devlink_pickup_dangling_consumers(child, new_sup); 2353a2dbc51SSaravana Kannan } 2363a2dbc51SSaravana Kannan 2379ed98953SRafael J. Wysocki static DEFINE_MUTEX(device_links_lock); 2389ed98953SRafael J. Wysocki DEFINE_STATIC_SRCU(device_links_srcu); 2399ed98953SRafael J. Wysocki 2409ed98953SRafael J. Wysocki static inline void device_links_write_lock(void) 2419ed98953SRafael J. Wysocki { 2429ed98953SRafael J. Wysocki mutex_lock(&device_links_lock); 2439ed98953SRafael J. Wysocki } 2449ed98953SRafael J. Wysocki 2459ed98953SRafael J. Wysocki static inline void device_links_write_unlock(void) 2469ed98953SRafael J. Wysocki { 2479ed98953SRafael J. Wysocki mutex_unlock(&device_links_lock); 2489ed98953SRafael J. Wysocki } 2499ed98953SRafael J. Wysocki 25068464d79SJules Irenge int device_links_read_lock(void) __acquires(&device_links_srcu) 2519ed98953SRafael J. Wysocki { 2529ed98953SRafael J. Wysocki return srcu_read_lock(&device_links_srcu); 2539ed98953SRafael J. Wysocki } 2549ed98953SRafael J. Wysocki 255ab7789c5SJules Irenge void device_links_read_unlock(int idx) __releases(&device_links_srcu) 2569ed98953SRafael J. Wysocki { 2579ed98953SRafael J. Wysocki srcu_read_unlock(&device_links_srcu, idx); 2589ed98953SRafael J. Wysocki } 259c2fa1e1bSJoel Fernandes (Google) 260c2fa1e1bSJoel Fernandes (Google) int device_links_read_lock_held(void) 261c2fa1e1bSJoel Fernandes (Google) { 262c2fa1e1bSJoel Fernandes (Google) return srcu_read_lock_held(&device_links_srcu); 263c2fa1e1bSJoel Fernandes (Google) } 26480dd33cfSRafael J. Wysocki 26580dd33cfSRafael J. Wysocki static void device_link_synchronize_removal(void) 26680dd33cfSRafael J. Wysocki { 26780dd33cfSRafael J. Wysocki synchronize_srcu(&device_links_srcu); 26880dd33cfSRafael J. Wysocki } 2690c871315SRafael J. Wysocki 2700c871315SRafael J. Wysocki static void device_link_remove_from_lists(struct device_link *link) 2710c871315SRafael J. Wysocki { 2720c871315SRafael J. Wysocki list_del_rcu(&link->s_node); 2730c871315SRafael J. Wysocki list_del_rcu(&link->c_node); 2740c871315SRafael J. Wysocki } 2759ed98953SRafael J. Wysocki 2763d1cf435SRafael J. Wysocki static bool device_is_ancestor(struct device *dev, struct device *target) 2773d1cf435SRafael J. Wysocki { 2783d1cf435SRafael J. Wysocki while (target->parent) { 2793d1cf435SRafael J. Wysocki target = target->parent; 2803d1cf435SRafael J. Wysocki if (dev == target) 2813d1cf435SRafael J. Wysocki return true; 2823d1cf435SRafael J. Wysocki } 2833d1cf435SRafael J. Wysocki return false; 2843d1cf435SRafael J. Wysocki } 2853d1cf435SRafael J. Wysocki 28667cad5c6SSaravana Kannan static inline bool device_link_flag_is_sync_state_only(u32 flags) 28767cad5c6SSaravana Kannan { 28867cad5c6SSaravana Kannan return (flags & ~(DL_FLAG_INFERRED | DL_FLAG_CYCLE)) == 28967cad5c6SSaravana Kannan (DL_FLAG_SYNC_STATE_ONLY | DL_FLAG_MANAGED); 29067cad5c6SSaravana Kannan } 29167cad5c6SSaravana Kannan 2929ed98953SRafael J. Wysocki /** 2939ed98953SRafael J. Wysocki * device_is_dependent - Check if one device depends on another one 2949ed98953SRafael J. Wysocki * @dev: Device to check dependencies for. 2959ed98953SRafael J. Wysocki * @target: Device to check against. 2969ed98953SRafael J. Wysocki * 2979ed98953SRafael J. Wysocki * Check if @target depends on @dev or any device dependent on it (its child or 2989ed98953SRafael J. Wysocki * its consumer etc). Return 1 if that is the case or 0 otherwise. 2999ed98953SRafael J. Wysocki */ 3007d34ca38SSaravana Kannan int device_is_dependent(struct device *dev, void *target) 3019ed98953SRafael J. Wysocki { 3029ed98953SRafael J. Wysocki struct device_link *link; 3039ed98953SRafael J. Wysocki int ret; 3049ed98953SRafael J. Wysocki 3053d1cf435SRafael J. Wysocki /* 3063d1cf435SRafael J. Wysocki * The "ancestors" check is needed to catch the case when the target 3073d1cf435SRafael J. Wysocki * device has not been completely initialized yet and it is still 3083d1cf435SRafael J. Wysocki * missing from the list of children of its parent device. 3093d1cf435SRafael J. Wysocki */ 3103d1cf435SRafael J. Wysocki if (dev == target || device_is_ancestor(dev, target)) 3119ed98953SRafael J. Wysocki return 1; 3129ed98953SRafael J. Wysocki 3139ed98953SRafael J. Wysocki ret = device_for_each_child(dev, target, device_is_dependent); 3149ed98953SRafael J. Wysocki if (ret) 3159ed98953SRafael J. Wysocki return ret; 3169ed98953SRafael J. Wysocki 3179ed98953SRafael J. Wysocki list_for_each_entry(link, &dev->links.consumers, s_node) { 31867cad5c6SSaravana Kannan if (device_link_flag_is_sync_state_only(link->flags)) 31905ef983eSSaravana Kannan continue; 32005ef983eSSaravana Kannan 321e16f4f3eSBenjamin Gaignard if (link->consumer == target) 3229ed98953SRafael J. Wysocki return 1; 3239ed98953SRafael J. Wysocki 3249ed98953SRafael J. Wysocki ret = device_is_dependent(link->consumer, target); 3259ed98953SRafael J. Wysocki if (ret) 3269ed98953SRafael J. Wysocki break; 3279ed98953SRafael J. Wysocki } 3289ed98953SRafael J. Wysocki return ret; 3299ed98953SRafael J. Wysocki } 3309ed98953SRafael J. Wysocki 331515db266SRafael J. Wysocki static void device_link_init_status(struct device_link *link, 332515db266SRafael J. Wysocki struct device *consumer, 333515db266SRafael J. Wysocki struct device *supplier) 334515db266SRafael J. Wysocki { 335515db266SRafael J. Wysocki switch (supplier->links.status) { 336515db266SRafael J. Wysocki case DL_DEV_PROBING: 337515db266SRafael J. Wysocki switch (consumer->links.status) { 338515db266SRafael J. Wysocki case DL_DEV_PROBING: 339515db266SRafael J. Wysocki /* 340515db266SRafael J. Wysocki * A consumer driver can create a link to a supplier 341515db266SRafael J. Wysocki * that has not completed its probing yet as long as it 342515db266SRafael J. Wysocki * knows that the supplier is already functional (for 343515db266SRafael J. Wysocki * example, it has just acquired some resources from the 344515db266SRafael J. Wysocki * supplier). 345515db266SRafael J. Wysocki */ 346515db266SRafael J. Wysocki link->status = DL_STATE_CONSUMER_PROBE; 347515db266SRafael J. Wysocki break; 348515db266SRafael J. Wysocki default: 349515db266SRafael J. Wysocki link->status = DL_STATE_DORMANT; 350515db266SRafael J. Wysocki break; 351515db266SRafael J. Wysocki } 352515db266SRafael J. Wysocki break; 353515db266SRafael J. Wysocki case DL_DEV_DRIVER_BOUND: 354515db266SRafael J. Wysocki switch (consumer->links.status) { 355515db266SRafael J. Wysocki case DL_DEV_PROBING: 356515db266SRafael J. Wysocki link->status = DL_STATE_CONSUMER_PROBE; 357515db266SRafael J. Wysocki break; 358515db266SRafael J. Wysocki case DL_DEV_DRIVER_BOUND: 359515db266SRafael J. Wysocki link->status = DL_STATE_ACTIVE; 360515db266SRafael J. Wysocki break; 361515db266SRafael J. Wysocki default: 362515db266SRafael J. Wysocki link->status = DL_STATE_AVAILABLE; 363515db266SRafael J. Wysocki break; 364515db266SRafael J. Wysocki } 365515db266SRafael J. Wysocki break; 366515db266SRafael J. Wysocki case DL_DEV_UNBINDING: 367515db266SRafael J. Wysocki link->status = DL_STATE_SUPPLIER_UNBIND; 368515db266SRafael J. Wysocki break; 369515db266SRafael J. Wysocki default: 370515db266SRafael J. Wysocki link->status = DL_STATE_DORMANT; 371515db266SRafael J. Wysocki break; 372515db266SRafael J. Wysocki } 373515db266SRafael J. Wysocki } 374515db266SRafael J. Wysocki 3759ed98953SRafael J. Wysocki static int device_reorder_to_tail(struct device *dev, void *not_used) 3769ed98953SRafael J. Wysocki { 3779ed98953SRafael J. Wysocki struct device_link *link; 3789ed98953SRafael J. Wysocki 3799ed98953SRafael J. Wysocki /* 3809ed98953SRafael J. Wysocki * Devices that have not been registered yet will be put to the ends 3819ed98953SRafael J. Wysocki * of the lists during the registration, so skip them here. 3829ed98953SRafael J. Wysocki */ 3839ed98953SRafael J. Wysocki if (device_is_registered(dev)) 3849ed98953SRafael J. Wysocki devices_kset_move_last(dev); 3859ed98953SRafael J. Wysocki 3869ed98953SRafael J. Wysocki if (device_pm_initialized(dev)) 3879ed98953SRafael J. Wysocki device_pm_move_last(dev); 3889ed98953SRafael J. Wysocki 3899ed98953SRafael J. Wysocki device_for_each_child(dev, NULL, device_reorder_to_tail); 39005ef983eSSaravana Kannan list_for_each_entry(link, &dev->links.consumers, s_node) { 39167cad5c6SSaravana Kannan if (device_link_flag_is_sync_state_only(link->flags)) 39205ef983eSSaravana Kannan continue; 3939ed98953SRafael J. Wysocki device_reorder_to_tail(link->consumer, NULL); 39405ef983eSSaravana Kannan } 3959ed98953SRafael J. Wysocki 3969ed98953SRafael J. Wysocki return 0; 3979ed98953SRafael J. Wysocki } 3989ed98953SRafael J. Wysocki 3999ed98953SRafael J. Wysocki /** 400494fd7b7SFeng Kan * device_pm_move_to_tail - Move set of devices to the end of device lists 401494fd7b7SFeng Kan * @dev: Device to move 402494fd7b7SFeng Kan * 403494fd7b7SFeng Kan * This is a device_reorder_to_tail() wrapper taking the requisite locks. 404494fd7b7SFeng Kan * 405494fd7b7SFeng Kan * It moves the @dev along with all of its children and all of its consumers 406494fd7b7SFeng Kan * to the ends of the device_kset and dpm_list, recursively. 407494fd7b7SFeng Kan */ 408494fd7b7SFeng Kan void device_pm_move_to_tail(struct device *dev) 409494fd7b7SFeng Kan { 410494fd7b7SFeng Kan int idx; 411494fd7b7SFeng Kan 412494fd7b7SFeng Kan idx = device_links_read_lock(); 413494fd7b7SFeng Kan device_pm_lock(); 414494fd7b7SFeng Kan device_reorder_to_tail(dev, NULL); 415494fd7b7SFeng Kan device_pm_unlock(); 416494fd7b7SFeng Kan device_links_read_unlock(idx); 417494fd7b7SFeng Kan } 418494fd7b7SFeng Kan 419287905e6SSaravana Kannan #define to_devlink(dev) container_of((dev), struct device_link, link_dev) 420287905e6SSaravana Kannan 421287905e6SSaravana Kannan static ssize_t status_show(struct device *dev, 422287905e6SSaravana Kannan struct device_attribute *attr, char *buf) 423287905e6SSaravana Kannan { 424948b3edbSJoe Perches const char *output; 425287905e6SSaravana Kannan 426287905e6SSaravana Kannan switch (to_devlink(dev)->status) { 427287905e6SSaravana Kannan case DL_STATE_NONE: 428948b3edbSJoe Perches output = "not tracked"; 429948b3edbSJoe Perches break; 430287905e6SSaravana Kannan case DL_STATE_DORMANT: 431948b3edbSJoe Perches output = "dormant"; 432948b3edbSJoe Perches break; 433287905e6SSaravana Kannan case DL_STATE_AVAILABLE: 434948b3edbSJoe Perches output = "available"; 435948b3edbSJoe Perches break; 436287905e6SSaravana Kannan case DL_STATE_CONSUMER_PROBE: 437948b3edbSJoe Perches output = "consumer probing"; 438948b3edbSJoe Perches break; 439287905e6SSaravana Kannan case DL_STATE_ACTIVE: 440948b3edbSJoe Perches output = "active"; 441948b3edbSJoe Perches break; 442287905e6SSaravana Kannan case DL_STATE_SUPPLIER_UNBIND: 443948b3edbSJoe Perches output = "supplier unbinding"; 444948b3edbSJoe Perches break; 445287905e6SSaravana Kannan default: 446948b3edbSJoe Perches output = "unknown"; 447948b3edbSJoe Perches break; 448287905e6SSaravana Kannan } 449948b3edbSJoe Perches 450948b3edbSJoe Perches return sysfs_emit(buf, "%s\n", output); 451287905e6SSaravana Kannan } 452287905e6SSaravana Kannan static DEVICE_ATTR_RO(status); 453287905e6SSaravana Kannan 454287905e6SSaravana Kannan static ssize_t auto_remove_on_show(struct device *dev, 455287905e6SSaravana Kannan struct device_attribute *attr, char *buf) 456287905e6SSaravana Kannan { 457287905e6SSaravana Kannan struct device_link *link = to_devlink(dev); 458973c3911SJoe Perches const char *output; 459287905e6SSaravana Kannan 460287905e6SSaravana Kannan if (link->flags & DL_FLAG_AUTOREMOVE_SUPPLIER) 461973c3911SJoe Perches output = "supplier unbind"; 462287905e6SSaravana Kannan else if (link->flags & DL_FLAG_AUTOREMOVE_CONSUMER) 463973c3911SJoe Perches output = "consumer unbind"; 464287905e6SSaravana Kannan else 465973c3911SJoe Perches output = "never"; 466287905e6SSaravana Kannan 467973c3911SJoe Perches return sysfs_emit(buf, "%s\n", output); 468287905e6SSaravana Kannan } 469287905e6SSaravana Kannan static DEVICE_ATTR_RO(auto_remove_on); 470287905e6SSaravana Kannan 471287905e6SSaravana Kannan static ssize_t runtime_pm_show(struct device *dev, 472287905e6SSaravana Kannan struct device_attribute *attr, char *buf) 473287905e6SSaravana Kannan { 474287905e6SSaravana Kannan struct device_link *link = to_devlink(dev); 475287905e6SSaravana Kannan 476aa838896SJoe Perches return sysfs_emit(buf, "%d\n", !!(link->flags & DL_FLAG_PM_RUNTIME)); 477287905e6SSaravana Kannan } 478287905e6SSaravana Kannan static DEVICE_ATTR_RO(runtime_pm); 479287905e6SSaravana Kannan 480287905e6SSaravana Kannan static ssize_t sync_state_only_show(struct device *dev, 481287905e6SSaravana Kannan struct device_attribute *attr, char *buf) 482287905e6SSaravana Kannan { 483287905e6SSaravana Kannan struct device_link *link = to_devlink(dev); 484287905e6SSaravana Kannan 485aa838896SJoe Perches return sysfs_emit(buf, "%d\n", 486aa838896SJoe Perches !!(link->flags & DL_FLAG_SYNC_STATE_ONLY)); 487287905e6SSaravana Kannan } 488287905e6SSaravana Kannan static DEVICE_ATTR_RO(sync_state_only); 489287905e6SSaravana Kannan 490287905e6SSaravana Kannan static struct attribute *devlink_attrs[] = { 491287905e6SSaravana Kannan &dev_attr_status.attr, 492287905e6SSaravana Kannan &dev_attr_auto_remove_on.attr, 493287905e6SSaravana Kannan &dev_attr_runtime_pm.attr, 494287905e6SSaravana Kannan &dev_attr_sync_state_only.attr, 495287905e6SSaravana Kannan NULL, 496287905e6SSaravana Kannan }; 497287905e6SSaravana Kannan ATTRIBUTE_GROUPS(devlink); 498287905e6SSaravana Kannan 49980dd33cfSRafael J. Wysocki static void device_link_release_fn(struct work_struct *work) 500843e600bSSaravana Kannan { 50180dd33cfSRafael J. Wysocki struct device_link *link = container_of(work, struct device_link, rm_work); 50280dd33cfSRafael J. Wysocki 50380dd33cfSRafael J. Wysocki /* Ensure that all references to the link object have been dropped. */ 50480dd33cfSRafael J. Wysocki device_link_synchronize_removal(); 50580dd33cfSRafael J. Wysocki 50607358194SRafael J. Wysocki pm_runtime_release_supplier(link); 50788737106SRafael J. Wysocki /* 50888737106SRafael J. Wysocki * If supplier_preactivated is set, the link has been dropped between 50988737106SRafael J. Wysocki * the pm_runtime_get_suppliers() and pm_runtime_put_suppliers() calls 51088737106SRafael J. Wysocki * in __driver_probe_device(). In that case, drop the supplier's 51188737106SRafael J. Wysocki * PM-runtime usage counter to remove the reference taken by 51288737106SRafael J. Wysocki * pm_runtime_get_suppliers(). 51388737106SRafael J. Wysocki */ 51488737106SRafael J. Wysocki if (link->supplier_preactivated) 51588737106SRafael J. Wysocki pm_runtime_put_noidle(link->supplier); 51688737106SRafael J. Wysocki 51707358194SRafael J. Wysocki pm_request_idle(link->supplier); 518843e600bSSaravana Kannan 519843e600bSSaravana Kannan put_device(link->consumer); 520843e600bSSaravana Kannan put_device(link->supplier); 521843e600bSSaravana Kannan kfree(link); 522843e600bSSaravana Kannan } 523843e600bSSaravana Kannan 524287905e6SSaravana Kannan static void devlink_dev_release(struct device *dev) 525287905e6SSaravana Kannan { 526843e600bSSaravana Kannan struct device_link *link = to_devlink(dev); 527843e600bSSaravana Kannan 52880dd33cfSRafael J. Wysocki INIT_WORK(&link->rm_work, device_link_release_fn); 52980dd33cfSRafael J. Wysocki /* 53080dd33cfSRafael J. Wysocki * It may take a while to complete this work because of the SRCU 53180dd33cfSRafael J. Wysocki * synchronization in device_link_release_fn() and if the consumer or 53280dd33cfSRafael J. Wysocki * supplier devices get deleted when it runs, so put it into the "long" 53380dd33cfSRafael J. Wysocki * workqueue. 53480dd33cfSRafael J. Wysocki */ 53580dd33cfSRafael J. Wysocki queue_work(system_long_wq, &link->rm_work); 536287905e6SSaravana Kannan } 537287905e6SSaravana Kannan 538287905e6SSaravana Kannan static struct class devlink_class = { 539287905e6SSaravana Kannan .name = "devlink", 540287905e6SSaravana Kannan .dev_groups = devlink_groups, 541287905e6SSaravana Kannan .dev_release = devlink_dev_release, 542287905e6SSaravana Kannan }; 543287905e6SSaravana Kannan 544287905e6SSaravana Kannan static int devlink_add_symlinks(struct device *dev, 545287905e6SSaravana Kannan struct class_interface *class_intf) 546287905e6SSaravana Kannan { 547287905e6SSaravana Kannan int ret; 548287905e6SSaravana Kannan size_t len; 549287905e6SSaravana Kannan struct device_link *link = to_devlink(dev); 550287905e6SSaravana Kannan struct device *sup = link->supplier; 551287905e6SSaravana Kannan struct device *con = link->consumer; 552287905e6SSaravana Kannan char *buf; 553287905e6SSaravana Kannan 554e020ff61SSaravana Kannan len = max(strlen(dev_bus_name(sup)) + strlen(dev_name(sup)), 555e020ff61SSaravana Kannan strlen(dev_bus_name(con)) + strlen(dev_name(con))); 556e020ff61SSaravana Kannan len += strlen(":"); 557287905e6SSaravana Kannan len += strlen("supplier:") + 1; 558287905e6SSaravana Kannan buf = kzalloc(len, GFP_KERNEL); 559287905e6SSaravana Kannan if (!buf) 560287905e6SSaravana Kannan return -ENOMEM; 561287905e6SSaravana Kannan 562287905e6SSaravana Kannan ret = sysfs_create_link(&link->link_dev.kobj, &sup->kobj, "supplier"); 563287905e6SSaravana Kannan if (ret) 564287905e6SSaravana Kannan goto out; 565287905e6SSaravana Kannan 566287905e6SSaravana Kannan ret = sysfs_create_link(&link->link_dev.kobj, &con->kobj, "consumer"); 567287905e6SSaravana Kannan if (ret) 568287905e6SSaravana Kannan goto err_con; 569287905e6SSaravana Kannan 570e020ff61SSaravana Kannan snprintf(buf, len, "consumer:%s:%s", dev_bus_name(con), dev_name(con)); 571287905e6SSaravana Kannan ret = sysfs_create_link(&sup->kobj, &link->link_dev.kobj, buf); 572287905e6SSaravana Kannan if (ret) 573287905e6SSaravana Kannan goto err_con_dev; 574287905e6SSaravana Kannan 575e020ff61SSaravana Kannan snprintf(buf, len, "supplier:%s:%s", dev_bus_name(sup), dev_name(sup)); 576287905e6SSaravana Kannan ret = sysfs_create_link(&con->kobj, &link->link_dev.kobj, buf); 577287905e6SSaravana Kannan if (ret) 578287905e6SSaravana Kannan goto err_sup_dev; 579287905e6SSaravana Kannan 580287905e6SSaravana Kannan goto out; 581287905e6SSaravana Kannan 582287905e6SSaravana Kannan err_sup_dev: 583e020ff61SSaravana Kannan snprintf(buf, len, "consumer:%s:%s", dev_bus_name(con), dev_name(con)); 584287905e6SSaravana Kannan sysfs_remove_link(&sup->kobj, buf); 585287905e6SSaravana Kannan err_con_dev: 586287905e6SSaravana Kannan sysfs_remove_link(&link->link_dev.kobj, "consumer"); 587287905e6SSaravana Kannan err_con: 588287905e6SSaravana Kannan sysfs_remove_link(&link->link_dev.kobj, "supplier"); 589287905e6SSaravana Kannan out: 590287905e6SSaravana Kannan kfree(buf); 591287905e6SSaravana Kannan return ret; 592287905e6SSaravana Kannan } 593287905e6SSaravana Kannan 594287905e6SSaravana Kannan static void devlink_remove_symlinks(struct device *dev, 595287905e6SSaravana Kannan struct class_interface *class_intf) 596287905e6SSaravana Kannan { 597287905e6SSaravana Kannan struct device_link *link = to_devlink(dev); 598287905e6SSaravana Kannan size_t len; 599287905e6SSaravana Kannan struct device *sup = link->supplier; 600287905e6SSaravana Kannan struct device *con = link->consumer; 601287905e6SSaravana Kannan char *buf; 602287905e6SSaravana Kannan 603287905e6SSaravana Kannan sysfs_remove_link(&link->link_dev.kobj, "consumer"); 604287905e6SSaravana Kannan sysfs_remove_link(&link->link_dev.kobj, "supplier"); 605287905e6SSaravana Kannan 606e020ff61SSaravana Kannan len = max(strlen(dev_bus_name(sup)) + strlen(dev_name(sup)), 607e020ff61SSaravana Kannan strlen(dev_bus_name(con)) + strlen(dev_name(con))); 608e020ff61SSaravana Kannan len += strlen(":"); 609287905e6SSaravana Kannan len += strlen("supplier:") + 1; 610287905e6SSaravana Kannan buf = kzalloc(len, GFP_KERNEL); 611287905e6SSaravana Kannan if (!buf) { 612287905e6SSaravana Kannan WARN(1, "Unable to properly free device link symlinks!\n"); 613287905e6SSaravana Kannan return; 614287905e6SSaravana Kannan } 615287905e6SSaravana Kannan 616e64daad6SAdrian Hunter if (device_is_registered(con)) { 617e020ff61SSaravana Kannan snprintf(buf, len, "supplier:%s:%s", dev_bus_name(sup), dev_name(sup)); 618287905e6SSaravana Kannan sysfs_remove_link(&con->kobj, buf); 619e64daad6SAdrian Hunter } 620e020ff61SSaravana Kannan snprintf(buf, len, "consumer:%s:%s", dev_bus_name(con), dev_name(con)); 621287905e6SSaravana Kannan sysfs_remove_link(&sup->kobj, buf); 622287905e6SSaravana Kannan kfree(buf); 623287905e6SSaravana Kannan } 624287905e6SSaravana Kannan 625287905e6SSaravana Kannan static struct class_interface devlink_class_intf = { 626287905e6SSaravana Kannan .class = &devlink_class, 627287905e6SSaravana Kannan .add_dev = devlink_add_symlinks, 628287905e6SSaravana Kannan .remove_dev = devlink_remove_symlinks, 629287905e6SSaravana Kannan }; 630287905e6SSaravana Kannan 631287905e6SSaravana Kannan static int __init devlink_class_init(void) 632287905e6SSaravana Kannan { 633287905e6SSaravana Kannan int ret; 634287905e6SSaravana Kannan 635287905e6SSaravana Kannan ret = class_register(&devlink_class); 636287905e6SSaravana Kannan if (ret) 637287905e6SSaravana Kannan return ret; 638287905e6SSaravana Kannan 639287905e6SSaravana Kannan ret = class_interface_register(&devlink_class_intf); 640287905e6SSaravana Kannan if (ret) 641287905e6SSaravana Kannan class_unregister(&devlink_class); 642287905e6SSaravana Kannan 643287905e6SSaravana Kannan return ret; 644287905e6SSaravana Kannan } 645287905e6SSaravana Kannan postcore_initcall(devlink_class_init); 646287905e6SSaravana Kannan 647515db266SRafael J. Wysocki #define DL_MANAGED_LINK_FLAGS (DL_FLAG_AUTOREMOVE_CONSUMER | \ 648515db266SRafael J. Wysocki DL_FLAG_AUTOREMOVE_SUPPLIER | \ 64905ef983eSSaravana Kannan DL_FLAG_AUTOPROBE_CONSUMER | \ 6504b9bbb29SSaravana Kannan DL_FLAG_SYNC_STATE_ONLY | \ 65167cad5c6SSaravana Kannan DL_FLAG_INFERRED | \ 65267cad5c6SSaravana Kannan DL_FLAG_CYCLE) 653515db266SRafael J. Wysocki 654fb583c8eSRafael J. Wysocki #define DL_ADD_VALID_FLAGS (DL_MANAGED_LINK_FLAGS | DL_FLAG_STATELESS | \ 655fb583c8eSRafael J. Wysocki DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE) 656fb583c8eSRafael J. Wysocki 657494fd7b7SFeng Kan /** 6589ed98953SRafael J. Wysocki * device_link_add - Create a link between two devices. 6599ed98953SRafael J. Wysocki * @consumer: Consumer end of the link. 6609ed98953SRafael J. Wysocki * @supplier: Supplier end of the link. 6619ed98953SRafael J. Wysocki * @flags: Link flags. 6629ed98953SRafael J. Wysocki * 66321d5c57bSRafael J. Wysocki * The caller is responsible for the proper synchronization of the link creation 66421d5c57bSRafael J. Wysocki * with runtime PM. First, setting the DL_FLAG_PM_RUNTIME flag will cause the 66521d5c57bSRafael J. Wysocki * runtime PM framework to take the link into account. Second, if the 66621d5c57bSRafael J. Wysocki * DL_FLAG_RPM_ACTIVE flag is set in addition to it, the supplier devices will 66721d5c57bSRafael J. Wysocki * be forced into the active meta state and reference-counted upon the creation 66821d5c57bSRafael J. Wysocki * of the link. If DL_FLAG_PM_RUNTIME is not set, DL_FLAG_RPM_ACTIVE will be 66921d5c57bSRafael J. Wysocki * ignored. 67021d5c57bSRafael J. Wysocki * 671515db266SRafael J. Wysocki * If DL_FLAG_STATELESS is set in @flags, the caller of this function is 672515db266SRafael J. Wysocki * expected to release the link returned by it directly with the help of either 673515db266SRafael J. Wysocki * device_link_del() or device_link_remove(). 67472175d4eSRafael J. Wysocki * 67572175d4eSRafael J. Wysocki * If that flag is not set, however, the caller of this function is handing the 67672175d4eSRafael J. Wysocki * management of the link over to the driver core entirely and its return value 67772175d4eSRafael J. Wysocki * can only be used to check whether or not the link is present. In that case, 67872175d4eSRafael J. Wysocki * the DL_FLAG_AUTOREMOVE_CONSUMER and DL_FLAG_AUTOREMOVE_SUPPLIER device link 67972175d4eSRafael J. Wysocki * flags can be used to indicate to the driver core when the link can be safely 68072175d4eSRafael J. Wysocki * deleted. Namely, setting one of them in @flags indicates to the driver core 68172175d4eSRafael J. Wysocki * that the link is not going to be used (by the given caller of this function) 68272175d4eSRafael J. Wysocki * after unbinding the consumer or supplier driver, respectively, from its 68372175d4eSRafael J. Wysocki * device, so the link can be deleted at that point. If none of them is set, 68472175d4eSRafael J. Wysocki * the link will be maintained until one of the devices pointed to by it (either 68572175d4eSRafael J. Wysocki * the consumer or the supplier) is unregistered. 686c8d50986SRafael J. Wysocki * 687e7dd4010SRafael J. Wysocki * Also, if DL_FLAG_STATELESS, DL_FLAG_AUTOREMOVE_CONSUMER and 688e7dd4010SRafael J. Wysocki * DL_FLAG_AUTOREMOVE_SUPPLIER are not set in @flags (that is, a persistent 689e7dd4010SRafael J. Wysocki * managed device link is being added), the DL_FLAG_AUTOPROBE_CONSUMER flag can 690d475f8eaSThierry Reding * be used to request the driver core to automatically probe for a consumer 691e7dd4010SRafael J. Wysocki * driver after successfully binding a driver to the supplier device. 692e7dd4010SRafael J. Wysocki * 693515db266SRafael J. Wysocki * The combination of DL_FLAG_STATELESS and one of DL_FLAG_AUTOREMOVE_CONSUMER, 694515db266SRafael J. Wysocki * DL_FLAG_AUTOREMOVE_SUPPLIER, or DL_FLAG_AUTOPROBE_CONSUMER set in @flags at 695515db266SRafael J. Wysocki * the same time is invalid and will cause NULL to be returned upfront. 696515db266SRafael J. Wysocki * However, if a device link between the given @consumer and @supplier pair 697515db266SRafael J. Wysocki * exists already when this function is called for them, the existing link will 698515db266SRafael J. Wysocki * be returned regardless of its current type and status (the link's flags may 699515db266SRafael J. Wysocki * be modified then). The caller of this function is then expected to treat 700515db266SRafael J. Wysocki * the link as though it has just been created, so (in particular) if 701515db266SRafael J. Wysocki * DL_FLAG_STATELESS was passed in @flags, the link needs to be released 702515db266SRafael J. Wysocki * explicitly when not needed any more (as stated above). 7039ed98953SRafael J. Wysocki * 7049ed98953SRafael J. Wysocki * A side effect of the link creation is re-ordering of dpm_list and the 7059ed98953SRafael J. Wysocki * devices_kset list by moving the consumer device and all devices depending 7069ed98953SRafael J. Wysocki * on it to the ends of these lists (that does not happen to devices that have 7079ed98953SRafael J. Wysocki * not been registered when this function is called). 7089ed98953SRafael J. Wysocki * 7099ed98953SRafael J. Wysocki * The supplier device is required to be registered when this function is called 7109ed98953SRafael J. Wysocki * and NULL will be returned if that is not the case. The consumer device need 71164df1148SLukas Wunner * not be registered, however. 7129ed98953SRafael J. Wysocki */ 7139ed98953SRafael J. Wysocki struct device_link *device_link_add(struct device *consumer, 7149ed98953SRafael J. Wysocki struct device *supplier, u32 flags) 7159ed98953SRafael J. Wysocki { 7169ed98953SRafael J. Wysocki struct device_link *link; 7179ed98953SRafael J. Wysocki 718f729a592SSaravana Kannan if (!consumer || !supplier || consumer == supplier || 719f729a592SSaravana Kannan flags & ~DL_ADD_VALID_FLAGS || 720515db266SRafael J. Wysocki (flags & DL_FLAG_STATELESS && flags & DL_MANAGED_LINK_FLAGS) || 721e7dd4010SRafael J. Wysocki (flags & DL_FLAG_AUTOPROBE_CONSUMER && 722e7dd4010SRafael J. Wysocki flags & (DL_FLAG_AUTOREMOVE_CONSUMER | 723e7dd4010SRafael J. Wysocki DL_FLAG_AUTOREMOVE_SUPPLIER))) 7249ed98953SRafael J. Wysocki return NULL; 7259ed98953SRafael J. Wysocki 7265db25c9eSRafael J. Wysocki if (flags & DL_FLAG_PM_RUNTIME && flags & DL_FLAG_RPM_ACTIVE) { 7275db25c9eSRafael J. Wysocki if (pm_runtime_get_sync(supplier) < 0) { 7285db25c9eSRafael J. Wysocki pm_runtime_put_noidle(supplier); 7295db25c9eSRafael J. Wysocki return NULL; 7305db25c9eSRafael J. Wysocki } 7315db25c9eSRafael J. Wysocki } 7325db25c9eSRafael J. Wysocki 733515db266SRafael J. Wysocki if (!(flags & DL_FLAG_STATELESS)) 734515db266SRafael J. Wysocki flags |= DL_FLAG_MANAGED; 735515db266SRafael J. Wysocki 73667cad5c6SSaravana Kannan if (flags & DL_FLAG_SYNC_STATE_ONLY && 73767cad5c6SSaravana Kannan !device_link_flag_is_sync_state_only(flags)) 73867cad5c6SSaravana Kannan return NULL; 73967cad5c6SSaravana Kannan 7409ed98953SRafael J. Wysocki device_links_write_lock(); 7419ed98953SRafael J. Wysocki device_pm_lock(); 7429ed98953SRafael J. Wysocki 7439ed98953SRafael J. Wysocki /* 7449ed98953SRafael J. Wysocki * If the supplier has not been fully registered yet or there is a 74505ef983eSSaravana Kannan * reverse (non-SYNC_STATE_ONLY) dependency between the consumer and 74605ef983eSSaravana Kannan * the supplier already in the graph, return NULL. If the link is a 74705ef983eSSaravana Kannan * SYNC_STATE_ONLY link, we don't check for reverse dependencies 74805ef983eSSaravana Kannan * because it only affects sync_state() callbacks. 7499ed98953SRafael J. Wysocki */ 7509ed98953SRafael J. Wysocki if (!device_pm_initialized(supplier) 75105ef983eSSaravana Kannan || (!(flags & DL_FLAG_SYNC_STATE_ONLY) && 75205ef983eSSaravana Kannan device_is_dependent(consumer, supplier))) { 7539ed98953SRafael J. Wysocki link = NULL; 7549ed98953SRafael J. Wysocki goto out; 7559ed98953SRafael J. Wysocki } 7569ed98953SRafael J. Wysocki 75772175d4eSRafael J. Wysocki /* 758ac66c5bbSSaravana Kannan * SYNC_STATE_ONLY links are useless once a consumer device has probed. 759ac66c5bbSSaravana Kannan * So, only create it if the consumer hasn't probed yet. 760ac66c5bbSSaravana Kannan */ 761ac66c5bbSSaravana Kannan if (flags & DL_FLAG_SYNC_STATE_ONLY && 762ac66c5bbSSaravana Kannan consumer->links.status != DL_DEV_NO_DRIVER && 763ac66c5bbSSaravana Kannan consumer->links.status != DL_DEV_PROBING) { 764ac66c5bbSSaravana Kannan link = NULL; 765ac66c5bbSSaravana Kannan goto out; 766ac66c5bbSSaravana Kannan } 767ac66c5bbSSaravana Kannan 768ac66c5bbSSaravana Kannan /* 76972175d4eSRafael J. Wysocki * DL_FLAG_AUTOREMOVE_SUPPLIER indicates that the link will be needed 77072175d4eSRafael J. Wysocki * longer than for DL_FLAG_AUTOREMOVE_CONSUMER and setting them both 77172175d4eSRafael J. Wysocki * together doesn't make sense, so prefer DL_FLAG_AUTOREMOVE_SUPPLIER. 77272175d4eSRafael J. Wysocki */ 77372175d4eSRafael J. Wysocki if (flags & DL_FLAG_AUTOREMOVE_SUPPLIER) 77472175d4eSRafael J. Wysocki flags &= ~DL_FLAG_AUTOREMOVE_CONSUMER; 77572175d4eSRafael J. Wysocki 776f265df55SRafael J. Wysocki list_for_each_entry(link, &supplier->links.consumers, s_node) { 777f265df55SRafael J. Wysocki if (link->consumer != consumer) 778f265df55SRafael J. Wysocki continue; 779f265df55SRafael J. Wysocki 7804b9bbb29SSaravana Kannan if (link->flags & DL_FLAG_INFERRED && 7814b9bbb29SSaravana Kannan !(flags & DL_FLAG_INFERRED)) 7824b9bbb29SSaravana Kannan link->flags &= ~DL_FLAG_INFERRED; 7834b9bbb29SSaravana Kannan 784e2f3cd83SRafael J. Wysocki if (flags & DL_FLAG_PM_RUNTIME) { 785e2f3cd83SRafael J. Wysocki if (!(link->flags & DL_FLAG_PM_RUNTIME)) { 7864c06c4e6SRafael J. Wysocki pm_runtime_new_link(consumer); 787e2f3cd83SRafael J. Wysocki link->flags |= DL_FLAG_PM_RUNTIME; 788e2f3cd83SRafael J. Wysocki } 789e2f3cd83SRafael J. Wysocki if (flags & DL_FLAG_RPM_ACTIVE) 79036003d4cSRafael J. Wysocki refcount_inc(&link->rpm_active); 791e2f3cd83SRafael J. Wysocki } 792e2f3cd83SRafael J. Wysocki 79372175d4eSRafael J. Wysocki if (flags & DL_FLAG_STATELESS) { 794ead18c23SLukas Wunner kref_get(&link->kref); 79521c27f06SSaravana Kannan if (link->flags & DL_FLAG_SYNC_STATE_ONLY && 79644e96049SSaravana Kannan !(link->flags & DL_FLAG_STATELESS)) { 79744e96049SSaravana Kannan link->flags |= DL_FLAG_STATELESS; 79805ef983eSSaravana Kannan goto reorder; 79944e96049SSaravana Kannan } else { 80044e96049SSaravana Kannan link->flags |= DL_FLAG_STATELESS; 8019ed98953SRafael J. Wysocki goto out; 802ead18c23SLukas Wunner } 80344e96049SSaravana Kannan } 8049ed98953SRafael J. Wysocki 80572175d4eSRafael J. Wysocki /* 80672175d4eSRafael J. Wysocki * If the life time of the link following from the new flags is 80772175d4eSRafael J. Wysocki * longer than indicated by the flags of the existing link, 80872175d4eSRafael J. Wysocki * update the existing link to stay around longer. 80972175d4eSRafael J. Wysocki */ 81072175d4eSRafael J. Wysocki if (flags & DL_FLAG_AUTOREMOVE_SUPPLIER) { 81172175d4eSRafael J. Wysocki if (link->flags & DL_FLAG_AUTOREMOVE_CONSUMER) { 81272175d4eSRafael J. Wysocki link->flags &= ~DL_FLAG_AUTOREMOVE_CONSUMER; 81372175d4eSRafael J. Wysocki link->flags |= DL_FLAG_AUTOREMOVE_SUPPLIER; 81472175d4eSRafael J. Wysocki } 81572175d4eSRafael J. Wysocki } else if (!(flags & DL_FLAG_AUTOREMOVE_CONSUMER)) { 81672175d4eSRafael J. Wysocki link->flags &= ~(DL_FLAG_AUTOREMOVE_CONSUMER | 81772175d4eSRafael J. Wysocki DL_FLAG_AUTOREMOVE_SUPPLIER); 81872175d4eSRafael J. Wysocki } 819515db266SRafael J. Wysocki if (!(link->flags & DL_FLAG_MANAGED)) { 820515db266SRafael J. Wysocki kref_get(&link->kref); 821515db266SRafael J. Wysocki link->flags |= DL_FLAG_MANAGED; 822515db266SRafael J. Wysocki device_link_init_status(link, consumer, supplier); 823515db266SRafael J. Wysocki } 82405ef983eSSaravana Kannan if (link->flags & DL_FLAG_SYNC_STATE_ONLY && 82505ef983eSSaravana Kannan !(flags & DL_FLAG_SYNC_STATE_ONLY)) { 82605ef983eSSaravana Kannan link->flags &= ~DL_FLAG_SYNC_STATE_ONLY; 82705ef983eSSaravana Kannan goto reorder; 82805ef983eSSaravana Kannan } 82905ef983eSSaravana Kannan 83072175d4eSRafael J. Wysocki goto out; 83172175d4eSRafael J. Wysocki } 83272175d4eSRafael J. Wysocki 83321d5c57bSRafael J. Wysocki link = kzalloc(sizeof(*link), GFP_KERNEL); 8349ed98953SRafael J. Wysocki if (!link) 8359ed98953SRafael J. Wysocki goto out; 8369ed98953SRafael J. Wysocki 837e2f3cd83SRafael J. Wysocki refcount_set(&link->rpm_active, 1); 838e2f3cd83SRafael J. Wysocki 8399ed98953SRafael J. Wysocki get_device(supplier); 8409ed98953SRafael J. Wysocki link->supplier = supplier; 8419ed98953SRafael J. Wysocki INIT_LIST_HEAD(&link->s_node); 8429ed98953SRafael J. Wysocki get_device(consumer); 8439ed98953SRafael J. Wysocki link->consumer = consumer; 8449ed98953SRafael J. Wysocki INIT_LIST_HEAD(&link->c_node); 8459ed98953SRafael J. Wysocki link->flags = flags; 846ead18c23SLukas Wunner kref_init(&link->kref); 8479ed98953SRafael J. Wysocki 848287905e6SSaravana Kannan link->link_dev.class = &devlink_class; 849287905e6SSaravana Kannan device_set_pm_not_required(&link->link_dev); 850e020ff61SSaravana Kannan dev_set_name(&link->link_dev, "%s:%s--%s:%s", 851e020ff61SSaravana Kannan dev_bus_name(supplier), dev_name(supplier), 852e020ff61SSaravana Kannan dev_bus_name(consumer), dev_name(consumer)); 853287905e6SSaravana Kannan if (device_register(&link->link_dev)) { 854df0a1814SYang Yingliang put_device(&link->link_dev); 855287905e6SSaravana Kannan link = NULL; 856287905e6SSaravana Kannan goto out; 857287905e6SSaravana Kannan } 858287905e6SSaravana Kannan 859287905e6SSaravana Kannan if (flags & DL_FLAG_PM_RUNTIME) { 860287905e6SSaravana Kannan if (flags & DL_FLAG_RPM_ACTIVE) 861287905e6SSaravana Kannan refcount_inc(&link->rpm_active); 862287905e6SSaravana Kannan 863287905e6SSaravana Kannan pm_runtime_new_link(consumer); 864287905e6SSaravana Kannan } 865287905e6SSaravana Kannan 86664df1148SLukas Wunner /* Determine the initial link state. */ 867515db266SRafael J. Wysocki if (flags & DL_FLAG_STATELESS) 8689ed98953SRafael J. Wysocki link->status = DL_STATE_NONE; 869515db266SRafael J. Wysocki else 870515db266SRafael J. Wysocki device_link_init_status(link, consumer, supplier); 8719ed98953SRafael J. Wysocki 8729ed98953SRafael J. Wysocki /* 87315cfb094SRafael J. Wysocki * Some callers expect the link creation during consumer driver probe to 87415cfb094SRafael J. Wysocki * resume the supplier even without DL_FLAG_RPM_ACTIVE. 87515cfb094SRafael J. Wysocki */ 87615cfb094SRafael J. Wysocki if (link->status == DL_STATE_CONSUMER_PROBE && 87715cfb094SRafael J. Wysocki flags & DL_FLAG_PM_RUNTIME) 87815cfb094SRafael J. Wysocki pm_runtime_resume(supplier); 87915cfb094SRafael J. Wysocki 88021c27f06SSaravana Kannan list_add_tail_rcu(&link->s_node, &supplier->links.consumers); 88121c27f06SSaravana Kannan list_add_tail_rcu(&link->c_node, &consumer->links.suppliers); 88221c27f06SSaravana Kannan 88305ef983eSSaravana Kannan if (flags & DL_FLAG_SYNC_STATE_ONLY) { 88405ef983eSSaravana Kannan dev_dbg(consumer, 88505ef983eSSaravana Kannan "Linked as a sync state only consumer to %s\n", 88605ef983eSSaravana Kannan dev_name(supplier)); 88705ef983eSSaravana Kannan goto out; 88805ef983eSSaravana Kannan } 88921c27f06SSaravana Kannan 89005ef983eSSaravana Kannan reorder: 89115cfb094SRafael J. Wysocki /* 8929ed98953SRafael J. Wysocki * Move the consumer and all of the devices depending on it to the end 8939ed98953SRafael J. Wysocki * of dpm_list and the devices_kset list. 8949ed98953SRafael J. Wysocki * 8959ed98953SRafael J. Wysocki * It is necessary to hold dpm_list locked throughout all that or else 8969ed98953SRafael J. Wysocki * we may end up suspending with a wrong ordering of it. 8979ed98953SRafael J. Wysocki */ 8989ed98953SRafael J. Wysocki device_reorder_to_tail(consumer, NULL); 8999ed98953SRafael J. Wysocki 9008a4b3269SJerome Brunet dev_dbg(consumer, "Linked as a consumer to %s\n", dev_name(supplier)); 9019ed98953SRafael J. Wysocki 9029ed98953SRafael J. Wysocki out: 9039ed98953SRafael J. Wysocki device_pm_unlock(); 9049ed98953SRafael J. Wysocki device_links_write_unlock(); 9055db25c9eSRafael J. Wysocki 906e2f3cd83SRafael J. Wysocki if ((flags & DL_FLAG_PM_RUNTIME && flags & DL_FLAG_RPM_ACTIVE) && !link) 9075db25c9eSRafael J. Wysocki pm_runtime_put(supplier); 9085db25c9eSRafael J. Wysocki 9099ed98953SRafael J. Wysocki return link; 9109ed98953SRafael J. Wysocki } 9119ed98953SRafael J. Wysocki EXPORT_SYMBOL_GPL(device_link_add); 9129ed98953SRafael J. Wysocki 913ead18c23SLukas Wunner static void __device_link_del(struct kref *kref) 9149ed98953SRafael J. Wysocki { 915ead18c23SLukas Wunner struct device_link *link = container_of(kref, struct device_link, kref); 916ead18c23SLukas Wunner 9178a4b3269SJerome Brunet dev_dbg(link->consumer, "Dropping the link to %s\n", 9189ed98953SRafael J. Wysocki dev_name(link->supplier)); 9199ed98953SRafael J. Wysocki 920e0e398e2SRafael J. Wysocki pm_runtime_drop_link(link); 921baa8809fSRafael J. Wysocki 9220c871315SRafael J. Wysocki device_link_remove_from_lists(link); 923843e600bSSaravana Kannan device_unregister(&link->link_dev); 9249ed98953SRafael J. Wysocki } 9259ed98953SRafael J. Wysocki 92672175d4eSRafael J. Wysocki static void device_link_put_kref(struct device_link *link) 92772175d4eSRafael J. Wysocki { 92872175d4eSRafael J. Wysocki if (link->flags & DL_FLAG_STATELESS) 92972175d4eSRafael J. Wysocki kref_put(&link->kref, __device_link_del); 930bf25967aSAdrian Hunter else if (!device_is_registered(link->consumer)) 931bf25967aSAdrian Hunter __device_link_del(&link->kref); 93272175d4eSRafael J. Wysocki else 93372175d4eSRafael J. Wysocki WARN(1, "Unable to drop a managed device link reference\n"); 93472175d4eSRafael J. Wysocki } 93572175d4eSRafael J. Wysocki 9369ed98953SRafael J. Wysocki /** 93772175d4eSRafael J. Wysocki * device_link_del - Delete a stateless link between two devices. 9389ed98953SRafael J. Wysocki * @link: Device link to delete. 9399ed98953SRafael J. Wysocki * 9409ed98953SRafael J. Wysocki * The caller must ensure proper synchronization of this function with runtime 941ead18c23SLukas Wunner * PM. If the link was added multiple times, it needs to be deleted as often. 942ead18c23SLukas Wunner * Care is required for hotplugged devices: Their links are purged on removal 943ead18c23SLukas Wunner * and calling device_link_del() is then no longer allowed. 9449ed98953SRafael J. Wysocki */ 9459ed98953SRafael J. Wysocki void device_link_del(struct device_link *link) 9469ed98953SRafael J. Wysocki { 9479ed98953SRafael J. Wysocki device_links_write_lock(); 94872175d4eSRafael J. Wysocki device_link_put_kref(link); 9499ed98953SRafael J. Wysocki device_links_write_unlock(); 9509ed98953SRafael J. Wysocki } 9519ed98953SRafael J. Wysocki EXPORT_SYMBOL_GPL(device_link_del); 9529ed98953SRafael J. Wysocki 953d8842211Spascal paillet /** 95472175d4eSRafael J. Wysocki * device_link_remove - Delete a stateless link between two devices. 955d8842211Spascal paillet * @consumer: Consumer end of the link. 956d8842211Spascal paillet * @supplier: Supplier end of the link. 957d8842211Spascal paillet * 958d8842211Spascal paillet * The caller must ensure proper synchronization of this function with runtime 959d8842211Spascal paillet * PM. 960d8842211Spascal paillet */ 961d8842211Spascal paillet void device_link_remove(void *consumer, struct device *supplier) 962d8842211Spascal paillet { 963d8842211Spascal paillet struct device_link *link; 964d8842211Spascal paillet 965d8842211Spascal paillet if (WARN_ON(consumer == supplier)) 966d8842211Spascal paillet return; 967d8842211Spascal paillet 968d8842211Spascal paillet device_links_write_lock(); 969d8842211Spascal paillet 970d8842211Spascal paillet list_for_each_entry(link, &supplier->links.consumers, s_node) { 971d8842211Spascal paillet if (link->consumer == consumer) { 97272175d4eSRafael J. Wysocki device_link_put_kref(link); 973d8842211Spascal paillet break; 974d8842211Spascal paillet } 975d8842211Spascal paillet } 976d8842211Spascal paillet 977d8842211Spascal paillet device_links_write_unlock(); 978d8842211Spascal paillet } 979d8842211Spascal paillet EXPORT_SYMBOL_GPL(device_link_remove); 980d8842211Spascal paillet 9819ed98953SRafael J. Wysocki static void device_links_missing_supplier(struct device *dev) 9829ed98953SRafael J. Wysocki { 9839ed98953SRafael J. Wysocki struct device_link *link; 9849ed98953SRafael J. Wysocki 9858c3e315dSSaravana Kannan list_for_each_entry(link, &dev->links.suppliers, c_node) { 9868c3e315dSSaravana Kannan if (link->status != DL_STATE_CONSUMER_PROBE) 9878c3e315dSSaravana Kannan continue; 9888c3e315dSSaravana Kannan 9898c3e315dSSaravana Kannan if (link->supplier->links.status == DL_DEV_DRIVER_BOUND) { 9909ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_AVAILABLE); 9918c3e315dSSaravana Kannan } else { 9928c3e315dSSaravana Kannan WARN_ON(!(link->flags & DL_FLAG_SYNC_STATE_ONLY)); 9938c3e315dSSaravana Kannan WRITE_ONCE(link->status, DL_STATE_DORMANT); 9948c3e315dSSaravana Kannan } 9958c3e315dSSaravana Kannan } 9969ed98953SRafael J. Wysocki } 9979ed98953SRafael J. Wysocki 9982f8c3ae8SSaravana Kannan static bool dev_is_best_effort(struct device *dev) 9992f8c3ae8SSaravana Kannan { 10008f486cabSSaravana Kannan return (fw_devlink_best_effort && dev->can_match) || 10018f486cabSSaravana Kannan (dev->fwnode && (dev->fwnode->flags & FWNODE_FLAG_BEST_EFFORT)); 10022f8c3ae8SSaravana Kannan } 10032f8c3ae8SSaravana Kannan 10046a6dfdf8SSaravana Kannan static struct fwnode_handle *fwnode_links_check_suppliers( 10056a6dfdf8SSaravana Kannan struct fwnode_handle *fwnode) 10066a6dfdf8SSaravana Kannan { 10076a6dfdf8SSaravana Kannan struct fwnode_link *link; 10086a6dfdf8SSaravana Kannan 10096a6dfdf8SSaravana Kannan if (!fwnode || fw_devlink_is_permissive()) 10106a6dfdf8SSaravana Kannan return NULL; 10116a6dfdf8SSaravana Kannan 10126a6dfdf8SSaravana Kannan list_for_each_entry(link, &fwnode->suppliers, c_hook) 10136a6dfdf8SSaravana Kannan if (!(link->flags & FWLINK_FLAG_CYCLE)) 10146a6dfdf8SSaravana Kannan return link->supplier; 10156a6dfdf8SSaravana Kannan 10166a6dfdf8SSaravana Kannan return NULL; 10176a6dfdf8SSaravana Kannan } 10186a6dfdf8SSaravana Kannan 10199ed98953SRafael J. Wysocki /** 10209ed98953SRafael J. Wysocki * device_links_check_suppliers - Check presence of supplier drivers. 10219ed98953SRafael J. Wysocki * @dev: Consumer device. 10229ed98953SRafael J. Wysocki * 10239ed98953SRafael J. Wysocki * Check links from this device to any suppliers. Walk the list of the device's 10249ed98953SRafael J. Wysocki * links to suppliers and see if all of them are available. If not, simply 10259ed98953SRafael J. Wysocki * return -EPROBE_DEFER. 10269ed98953SRafael J. Wysocki * 10279ed98953SRafael J. Wysocki * We need to guarantee that the supplier will not go away after the check has 10289ed98953SRafael J. Wysocki * been positive here. It only can go away in __device_release_driver() and 10299ed98953SRafael J. Wysocki * that function checks the device's links to consumers. This means we need to 10309ed98953SRafael J. Wysocki * mark the link as "consumer probe in progress" to make the supplier removal 10319ed98953SRafael J. Wysocki * wait for us to complete (or bad things may happen). 10329ed98953SRafael J. Wysocki * 1033515db266SRafael J. Wysocki * Links without the DL_FLAG_MANAGED flag set are ignored. 10349ed98953SRafael J. Wysocki */ 10359ed98953SRafael J. Wysocki int device_links_check_suppliers(struct device *dev) 10369ed98953SRafael J. Wysocki { 10379ed98953SRafael J. Wysocki struct device_link *link; 10382f8c3ae8SSaravana Kannan int ret = 0, fwnode_ret = 0; 103968223eeeSSaravana Kannan struct fwnode_handle *sup_fw; 10409ed98953SRafael J. Wysocki 1041e2ae9bccSSaravana Kannan /* 1042e2ae9bccSSaravana Kannan * Device waiting for supplier to become available is not allowed to 1043e2ae9bccSSaravana Kannan * probe. 1044e2ae9bccSSaravana Kannan */ 104525ac86c6SSaravana Kannan mutex_lock(&fwnode_link_lock); 10466a6dfdf8SSaravana Kannan sup_fw = fwnode_links_check_suppliers(dev->fwnode); 10476a6dfdf8SSaravana Kannan if (sup_fw) { 10482f8c3ae8SSaravana Kannan if (!dev_is_best_effort(dev)) { 10492f8c3ae8SSaravana Kannan fwnode_ret = -EPROBE_DEFER; 10502f8c3ae8SSaravana Kannan dev_err_probe(dev, -EPROBE_DEFER, 10510c058fb9SSaravana Kannan "wait for supplier %pfwf\n", sup_fw); 10522f8c3ae8SSaravana Kannan } else { 10532f8c3ae8SSaravana Kannan fwnode_ret = -EAGAIN; 10542f8c3ae8SSaravana Kannan } 1055e2ae9bccSSaravana Kannan } 105625ac86c6SSaravana Kannan mutex_unlock(&fwnode_link_lock); 10572f8c3ae8SSaravana Kannan if (fwnode_ret == -EPROBE_DEFER) 10582f8c3ae8SSaravana Kannan return fwnode_ret; 1059e2ae9bccSSaravana Kannan 10609ed98953SRafael J. Wysocki device_links_write_lock(); 10619ed98953SRafael J. Wysocki 10629ed98953SRafael J. Wysocki list_for_each_entry(link, &dev->links.suppliers, c_node) { 10638c3e315dSSaravana Kannan if (!(link->flags & DL_FLAG_MANAGED)) 10649ed98953SRafael J. Wysocki continue; 10659ed98953SRafael J. Wysocki 10668c3e315dSSaravana Kannan if (link->status != DL_STATE_AVAILABLE && 10678c3e315dSSaravana Kannan !(link->flags & DL_FLAG_SYNC_STATE_ONLY)) { 10682f8c3ae8SSaravana Kannan 10692f8c3ae8SSaravana Kannan if (dev_is_best_effort(dev) && 10702f8c3ae8SSaravana Kannan link->flags & DL_FLAG_INFERRED && 10712f8c3ae8SSaravana Kannan !link->supplier->can_match) { 10722f8c3ae8SSaravana Kannan ret = -EAGAIN; 10732f8c3ae8SSaravana Kannan continue; 10742f8c3ae8SSaravana Kannan } 10752f8c3ae8SSaravana Kannan 10769ed98953SRafael J. Wysocki device_links_missing_supplier(dev); 107768223eeeSSaravana Kannan dev_err_probe(dev, -EPROBE_DEFER, 107868223eeeSSaravana Kannan "supplier %s not ready\n", 10791f0dfa05SSaravana Kannan dev_name(link->supplier)); 10809ed98953SRafael J. Wysocki ret = -EPROBE_DEFER; 10819ed98953SRafael J. Wysocki break; 10829ed98953SRafael J. Wysocki } 10839ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_CONSUMER_PROBE); 10849ed98953SRafael J. Wysocki } 10859ed98953SRafael J. Wysocki dev->links.status = DL_DEV_PROBING; 10869ed98953SRafael J. Wysocki 10879ed98953SRafael J. Wysocki device_links_write_unlock(); 10882f8c3ae8SSaravana Kannan 10892f8c3ae8SSaravana Kannan return ret ? ret : fwnode_ret; 10909ed98953SRafael J. Wysocki } 10919ed98953SRafael J. Wysocki 109226e77708SSaravana Kannan /** 109326e77708SSaravana Kannan * __device_links_queue_sync_state - Queue a device for sync_state() callback 109426e77708SSaravana Kannan * @dev: Device to call sync_state() on 109526e77708SSaravana Kannan * @list: List head to queue the @dev on 109626e77708SSaravana Kannan * 109726e77708SSaravana Kannan * Queues a device for a sync_state() callback when the device links write lock 109826e77708SSaravana Kannan * isn't held. This allows the sync_state() execution flow to use device links 109926e77708SSaravana Kannan * APIs. The caller must ensure this function is called with 110026e77708SSaravana Kannan * device_links_write_lock() held. 110126e77708SSaravana Kannan * 110226e77708SSaravana Kannan * This function does a get_device() to make sure the device is not freed while 110326e77708SSaravana Kannan * on this list. 110426e77708SSaravana Kannan * 110526e77708SSaravana Kannan * So the caller must also ensure that device_links_flush_sync_list() is called 110626e77708SSaravana Kannan * as soon as the caller releases device_links_write_lock(). This is necessary 110726e77708SSaravana Kannan * to make sure the sync_state() is called in a timely fashion and the 110826e77708SSaravana Kannan * put_device() is called on this device. 110926e77708SSaravana Kannan */ 111026e77708SSaravana Kannan static void __device_links_queue_sync_state(struct device *dev, 111126e77708SSaravana Kannan struct list_head *list) 1112fc5a251dSSaravana Kannan { 1113fc5a251dSSaravana Kannan struct device_link *link; 1114fc5a251dSSaravana Kannan 111577036165SSaravana Kannan if (!dev_has_sync_state(dev)) 111677036165SSaravana Kannan return; 1117fc5a251dSSaravana Kannan if (dev->state_synced) 1118fc5a251dSSaravana Kannan return; 1119fc5a251dSSaravana Kannan 1120fc5a251dSSaravana Kannan list_for_each_entry(link, &dev->links.consumers, s_node) { 1121fc5a251dSSaravana Kannan if (!(link->flags & DL_FLAG_MANAGED)) 1122fc5a251dSSaravana Kannan continue; 1123fc5a251dSSaravana Kannan if (link->status != DL_STATE_ACTIVE) 1124fc5a251dSSaravana Kannan return; 1125fc5a251dSSaravana Kannan } 1126fc5a251dSSaravana Kannan 112726e77708SSaravana Kannan /* 112826e77708SSaravana Kannan * Set the flag here to avoid adding the same device to a list more 112926e77708SSaravana Kannan * than once. This can happen if new consumers get added to the device 113026e77708SSaravana Kannan * and probed before the list is flushed. 113126e77708SSaravana Kannan */ 113226e77708SSaravana Kannan dev->state_synced = true; 113326e77708SSaravana Kannan 11343b052a3eSSaravana Kannan if (WARN_ON(!list_empty(&dev->links.defer_sync))) 113526e77708SSaravana Kannan return; 113626e77708SSaravana Kannan 113726e77708SSaravana Kannan get_device(dev); 11383b052a3eSSaravana Kannan list_add_tail(&dev->links.defer_sync, list); 113926e77708SSaravana Kannan } 114026e77708SSaravana Kannan 114126e77708SSaravana Kannan /** 114226e77708SSaravana Kannan * device_links_flush_sync_list - Call sync_state() on a list of devices 114326e77708SSaravana Kannan * @list: List of devices to call sync_state() on 114421eb93f4SSaravana Kannan * @dont_lock_dev: Device for which lock is already held by the caller 114526e77708SSaravana Kannan * 114626e77708SSaravana Kannan * Calls sync_state() on all the devices that have been queued for it. This 114721eb93f4SSaravana Kannan * function is used in conjunction with __device_links_queue_sync_state(). The 114821eb93f4SSaravana Kannan * @dont_lock_dev parameter is useful when this function is called from a 114921eb93f4SSaravana Kannan * context where a device lock is already held. 115026e77708SSaravana Kannan */ 115121eb93f4SSaravana Kannan static void device_links_flush_sync_list(struct list_head *list, 115221eb93f4SSaravana Kannan struct device *dont_lock_dev) 115326e77708SSaravana Kannan { 115426e77708SSaravana Kannan struct device *dev, *tmp; 115526e77708SSaravana Kannan 11563b052a3eSSaravana Kannan list_for_each_entry_safe(dev, tmp, list, links.defer_sync) { 11573b052a3eSSaravana Kannan list_del_init(&dev->links.defer_sync); 115826e77708SSaravana Kannan 115921eb93f4SSaravana Kannan if (dev != dont_lock_dev) 116026e77708SSaravana Kannan device_lock(dev); 116126e77708SSaravana Kannan 1162f8fb5766SSaravana Kannan dev_sync_state(dev); 1163fc5a251dSSaravana Kannan 116421eb93f4SSaravana Kannan if (dev != dont_lock_dev) 116526e77708SSaravana Kannan device_unlock(dev); 116626e77708SSaravana Kannan 116726e77708SSaravana Kannan put_device(dev); 116826e77708SSaravana Kannan } 1169fc5a251dSSaravana Kannan } 1170fc5a251dSSaravana Kannan 1171fc5a251dSSaravana Kannan void device_links_supplier_sync_state_pause(void) 1172fc5a251dSSaravana Kannan { 1173fc5a251dSSaravana Kannan device_links_write_lock(); 1174fc5a251dSSaravana Kannan defer_sync_state_count++; 1175fc5a251dSSaravana Kannan device_links_write_unlock(); 1176fc5a251dSSaravana Kannan } 1177fc5a251dSSaravana Kannan 1178fc5a251dSSaravana Kannan void device_links_supplier_sync_state_resume(void) 1179fc5a251dSSaravana Kannan { 1180fc5a251dSSaravana Kannan struct device *dev, *tmp; 118126e77708SSaravana Kannan LIST_HEAD(sync_list); 1182fc5a251dSSaravana Kannan 1183fc5a251dSSaravana Kannan device_links_write_lock(); 1184fc5a251dSSaravana Kannan if (!defer_sync_state_count) { 1185fc5a251dSSaravana Kannan WARN(true, "Unmatched sync_state pause/resume!"); 1186fc5a251dSSaravana Kannan goto out; 1187fc5a251dSSaravana Kannan } 1188fc5a251dSSaravana Kannan defer_sync_state_count--; 1189fc5a251dSSaravana Kannan if (defer_sync_state_count) 1190fc5a251dSSaravana Kannan goto out; 1191fc5a251dSSaravana Kannan 11923b052a3eSSaravana Kannan list_for_each_entry_safe(dev, tmp, &deferred_sync, links.defer_sync) { 119326e77708SSaravana Kannan /* 119426e77708SSaravana Kannan * Delete from deferred_sync list before queuing it to 11953b052a3eSSaravana Kannan * sync_list because defer_sync is used for both lists. 119626e77708SSaravana Kannan */ 11973b052a3eSSaravana Kannan list_del_init(&dev->links.defer_sync); 119826e77708SSaravana Kannan __device_links_queue_sync_state(dev, &sync_list); 1199fc5a251dSSaravana Kannan } 1200fc5a251dSSaravana Kannan out: 1201fc5a251dSSaravana Kannan device_links_write_unlock(); 120226e77708SSaravana Kannan 120321eb93f4SSaravana Kannan device_links_flush_sync_list(&sync_list, NULL); 1204fc5a251dSSaravana Kannan } 1205fc5a251dSSaravana Kannan 1206fc5a251dSSaravana Kannan static int sync_state_resume_initcall(void) 1207fc5a251dSSaravana Kannan { 1208fc5a251dSSaravana Kannan device_links_supplier_sync_state_resume(); 1209fc5a251dSSaravana Kannan return 0; 1210fc5a251dSSaravana Kannan } 1211fc5a251dSSaravana Kannan late_initcall(sync_state_resume_initcall); 1212fc5a251dSSaravana Kannan 1213fc5a251dSSaravana Kannan static void __device_links_supplier_defer_sync(struct device *sup) 1214fc5a251dSSaravana Kannan { 12153b052a3eSSaravana Kannan if (list_empty(&sup->links.defer_sync) && dev_has_sync_state(sup)) 12163b052a3eSSaravana Kannan list_add_tail(&sup->links.defer_sync, &deferred_sync); 1217fc5a251dSSaravana Kannan } 1218fc5a251dSSaravana Kannan 121921c27f06SSaravana Kannan static void device_link_drop_managed(struct device_link *link) 122021c27f06SSaravana Kannan { 122121c27f06SSaravana Kannan link->flags &= ~DL_FLAG_MANAGED; 122221c27f06SSaravana Kannan WRITE_ONCE(link->status, DL_STATE_NONE); 122321c27f06SSaravana Kannan kref_put(&link->kref, __device_link_del); 122421c27f06SSaravana Kannan } 122521c27f06SSaravana Kannan 1226da6d6475SSaravana Kannan static ssize_t waiting_for_supplier_show(struct device *dev, 1227da6d6475SSaravana Kannan struct device_attribute *attr, 1228da6d6475SSaravana Kannan char *buf) 1229da6d6475SSaravana Kannan { 1230da6d6475SSaravana Kannan bool val; 1231da6d6475SSaravana Kannan 1232da6d6475SSaravana Kannan device_lock(dev); 12336a6dfdf8SSaravana Kannan mutex_lock(&fwnode_link_lock); 12346a6dfdf8SSaravana Kannan val = !!fwnode_links_check_suppliers(dev->fwnode); 12356a6dfdf8SSaravana Kannan mutex_unlock(&fwnode_link_lock); 1236da6d6475SSaravana Kannan device_unlock(dev); 1237aa838896SJoe Perches return sysfs_emit(buf, "%u\n", val); 1238da6d6475SSaravana Kannan } 1239da6d6475SSaravana Kannan static DEVICE_ATTR_RO(waiting_for_supplier); 1240da6d6475SSaravana Kannan 12419ed98953SRafael J. Wysocki /** 1242b6f617dfSSaravana Kannan * device_links_force_bind - Prepares device to be force bound 1243b6f617dfSSaravana Kannan * @dev: Consumer device. 1244b6f617dfSSaravana Kannan * 1245b6f617dfSSaravana Kannan * device_bind_driver() force binds a device to a driver without calling any 1246b6f617dfSSaravana Kannan * driver probe functions. So the consumer really isn't going to wait for any 1247b6f617dfSSaravana Kannan * supplier before it's bound to the driver. We still want the device link 1248b6f617dfSSaravana Kannan * states to be sensible when this happens. 1249b6f617dfSSaravana Kannan * 1250b6f617dfSSaravana Kannan * In preparation for device_bind_driver(), this function goes through each 1251b6f617dfSSaravana Kannan * supplier device links and checks if the supplier is bound. If it is, then 1252b6f617dfSSaravana Kannan * the device link status is set to CONSUMER_PROBE. Otherwise, the device link 1253b6f617dfSSaravana Kannan * is dropped. Links without the DL_FLAG_MANAGED flag set are ignored. 1254b6f617dfSSaravana Kannan */ 1255b6f617dfSSaravana Kannan void device_links_force_bind(struct device *dev) 1256b6f617dfSSaravana Kannan { 1257b6f617dfSSaravana Kannan struct device_link *link, *ln; 1258b6f617dfSSaravana Kannan 1259b6f617dfSSaravana Kannan device_links_write_lock(); 1260b6f617dfSSaravana Kannan 1261b6f617dfSSaravana Kannan list_for_each_entry_safe(link, ln, &dev->links.suppliers, c_node) { 1262b6f617dfSSaravana Kannan if (!(link->flags & DL_FLAG_MANAGED)) 1263b6f617dfSSaravana Kannan continue; 1264b6f617dfSSaravana Kannan 1265b6f617dfSSaravana Kannan if (link->status != DL_STATE_AVAILABLE) { 1266b6f617dfSSaravana Kannan device_link_drop_managed(link); 1267b6f617dfSSaravana Kannan continue; 1268b6f617dfSSaravana Kannan } 1269b6f617dfSSaravana Kannan WRITE_ONCE(link->status, DL_STATE_CONSUMER_PROBE); 1270b6f617dfSSaravana Kannan } 1271b6f617dfSSaravana Kannan dev->links.status = DL_DEV_PROBING; 1272b6f617dfSSaravana Kannan 1273b6f617dfSSaravana Kannan device_links_write_unlock(); 1274b6f617dfSSaravana Kannan } 1275b6f617dfSSaravana Kannan 1276b6f617dfSSaravana Kannan /** 12779ed98953SRafael J. Wysocki * device_links_driver_bound - Update device links after probing its driver. 12789ed98953SRafael J. Wysocki * @dev: Device to update the links for. 12799ed98953SRafael J. Wysocki * 12809ed98953SRafael J. Wysocki * The probe has been successful, so update links from this device to any 12819ed98953SRafael J. Wysocki * consumers by changing their status to "available". 12829ed98953SRafael J. Wysocki * 12839ed98953SRafael J. Wysocki * Also change the status of @dev's links to suppliers to "active". 12849ed98953SRafael J. Wysocki * 1285515db266SRafael J. Wysocki * Links without the DL_FLAG_MANAGED flag set are ignored. 12869ed98953SRafael J. Wysocki */ 12879ed98953SRafael J. Wysocki void device_links_driver_bound(struct device *dev) 12889ed98953SRafael J. Wysocki { 128921c27f06SSaravana Kannan struct device_link *link, *ln; 129026e77708SSaravana Kannan LIST_HEAD(sync_list); 12919ed98953SRafael J. Wysocki 1292bcbbcfd5SSaravana Kannan /* 12939528e0d9SSaravana Kannan * If a device binds successfully, it's expected to have created all 1294bcbbcfd5SSaravana Kannan * the device links it needs to or make new device links as it needs 12959528e0d9SSaravana Kannan * them. So, fw_devlink no longer needs to create device links to any 12969528e0d9SSaravana Kannan * of the device's suppliers. 12979528e0d9SSaravana Kannan * 12983a2dbc51SSaravana Kannan * Also, if a child firmware node of this bound device is not added as a 12993a2dbc51SSaravana Kannan * device by now, assume it is never going to be added. Make this bound 13003a2dbc51SSaravana Kannan * device the fallback supplier to the dangling consumers of the child 13013a2dbc51SSaravana Kannan * firmware node because this bound device is probably implementing the 13023a2dbc51SSaravana Kannan * child firmware node functionality and we don't want the dangling 13033a2dbc51SSaravana Kannan * consumers to defer probe indefinitely waiting for a device for the 13043a2dbc51SSaravana Kannan * child firmware node. 1305bcbbcfd5SSaravana Kannan */ 13069528e0d9SSaravana Kannan if (dev->fwnode && dev->fwnode->dev == dev) { 13079528e0d9SSaravana Kannan struct fwnode_handle *child; 1308f9aa4606SSaravana Kannan fwnode_links_purge_suppliers(dev->fwnode); 13093a2dbc51SSaravana Kannan mutex_lock(&fwnode_link_lock); 13109528e0d9SSaravana Kannan fwnode_for_each_available_child_node(dev->fwnode, child) 13113a2dbc51SSaravana Kannan __fw_devlink_pickup_dangling_consumers(child, 13123a2dbc51SSaravana Kannan dev->fwnode); 13133a2dbc51SSaravana Kannan __fw_devlink_link_to_consumers(dev); 13143a2dbc51SSaravana Kannan mutex_unlock(&fwnode_link_lock); 13159528e0d9SSaravana Kannan } 1316da6d6475SSaravana Kannan device_remove_file(dev, &dev_attr_waiting_for_supplier); 1317bcbbcfd5SSaravana Kannan 13189ed98953SRafael J. Wysocki device_links_write_lock(); 13199ed98953SRafael J. Wysocki 13209ed98953SRafael J. Wysocki list_for_each_entry(link, &dev->links.consumers, s_node) { 1321515db266SRafael J. Wysocki if (!(link->flags & DL_FLAG_MANAGED)) 13229ed98953SRafael J. Wysocki continue; 13239ed98953SRafael J. Wysocki 132415cfb094SRafael J. Wysocki /* 132515cfb094SRafael J. Wysocki * Links created during consumer probe may be in the "consumer 132615cfb094SRafael J. Wysocki * probe" state to start with if the supplier is still probing 132715cfb094SRafael J. Wysocki * when they are created and they may become "active" if the 132815cfb094SRafael J. Wysocki * consumer probe returns first. Skip them here. 132915cfb094SRafael J. Wysocki */ 133015cfb094SRafael J. Wysocki if (link->status == DL_STATE_CONSUMER_PROBE || 133115cfb094SRafael J. Wysocki link->status == DL_STATE_ACTIVE) 133215cfb094SRafael J. Wysocki continue; 133315cfb094SRafael J. Wysocki 13349ed98953SRafael J. Wysocki WARN_ON(link->status != DL_STATE_DORMANT); 13359ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_AVAILABLE); 1336e7dd4010SRafael J. Wysocki 1337e7dd4010SRafael J. Wysocki if (link->flags & DL_FLAG_AUTOPROBE_CONSUMER) 1338e7dd4010SRafael J. Wysocki driver_deferred_probe_add(link->consumer); 13399ed98953SRafael J. Wysocki } 13409ed98953SRafael J. Wysocki 134121eb93f4SSaravana Kannan if (defer_sync_state_count) 134221eb93f4SSaravana Kannan __device_links_supplier_defer_sync(dev); 134321eb93f4SSaravana Kannan else 134421eb93f4SSaravana Kannan __device_links_queue_sync_state(dev, &sync_list); 134521eb93f4SSaravana Kannan 134621c27f06SSaravana Kannan list_for_each_entry_safe(link, ln, &dev->links.suppliers, c_node) { 134721c27f06SSaravana Kannan struct device *supplier; 134821c27f06SSaravana Kannan 1349515db266SRafael J. Wysocki if (!(link->flags & DL_FLAG_MANAGED)) 13509ed98953SRafael J. Wysocki continue; 13519ed98953SRafael J. Wysocki 135221c27f06SSaravana Kannan supplier = link->supplier; 135321c27f06SSaravana Kannan if (link->flags & DL_FLAG_SYNC_STATE_ONLY) { 135421c27f06SSaravana Kannan /* 135521c27f06SSaravana Kannan * When DL_FLAG_SYNC_STATE_ONLY is set, it means no 135621c27f06SSaravana Kannan * other DL_MANAGED_LINK_FLAGS have been set. So, it's 135721c27f06SSaravana Kannan * save to drop the managed link completely. 135821c27f06SSaravana Kannan */ 135921c27f06SSaravana Kannan device_link_drop_managed(link); 13602f8c3ae8SSaravana Kannan } else if (dev_is_best_effort(dev) && 13612f8c3ae8SSaravana Kannan link->flags & DL_FLAG_INFERRED && 13622f8c3ae8SSaravana Kannan link->status != DL_STATE_CONSUMER_PROBE && 13632f8c3ae8SSaravana Kannan !link->supplier->can_match) { 13642f8c3ae8SSaravana Kannan /* 13652f8c3ae8SSaravana Kannan * When dev_is_best_effort() is true, we ignore device 13662f8c3ae8SSaravana Kannan * links to suppliers that don't have a driver. If the 13672f8c3ae8SSaravana Kannan * consumer device still managed to probe, there's no 13682f8c3ae8SSaravana Kannan * point in maintaining a device link in a weird state 13692f8c3ae8SSaravana Kannan * (consumer probed before supplier). So delete it. 13702f8c3ae8SSaravana Kannan */ 13712f8c3ae8SSaravana Kannan device_link_drop_managed(link); 137221c27f06SSaravana Kannan } else { 13739ed98953SRafael J. Wysocki WARN_ON(link->status != DL_STATE_CONSUMER_PROBE); 13749ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_ACTIVE); 137521c27f06SSaravana Kannan } 1376fc5a251dSSaravana Kannan 137721c27f06SSaravana Kannan /* 137821c27f06SSaravana Kannan * This needs to be done even for the deleted 137921c27f06SSaravana Kannan * DL_FLAG_SYNC_STATE_ONLY device link in case it was the last 138021c27f06SSaravana Kannan * device link that was preventing the supplier from getting a 138121c27f06SSaravana Kannan * sync_state() call. 138221c27f06SSaravana Kannan */ 1383fc5a251dSSaravana Kannan if (defer_sync_state_count) 138421c27f06SSaravana Kannan __device_links_supplier_defer_sync(supplier); 1385fc5a251dSSaravana Kannan else 138621c27f06SSaravana Kannan __device_links_queue_sync_state(supplier, &sync_list); 13879ed98953SRafael J. Wysocki } 13889ed98953SRafael J. Wysocki 13899ed98953SRafael J. Wysocki dev->links.status = DL_DEV_DRIVER_BOUND; 13909ed98953SRafael J. Wysocki 13919ed98953SRafael J. Wysocki device_links_write_unlock(); 139226e77708SSaravana Kannan 139321eb93f4SSaravana Kannan device_links_flush_sync_list(&sync_list, dev); 13949ed98953SRafael J. Wysocki } 13959ed98953SRafael J. Wysocki 13969ed98953SRafael J. Wysocki /** 13979ed98953SRafael J. Wysocki * __device_links_no_driver - Update links of a device without a driver. 13989ed98953SRafael J. Wysocki * @dev: Device without a drvier. 13999ed98953SRafael J. Wysocki * 14009ed98953SRafael J. Wysocki * Delete all non-persistent links from this device to any suppliers. 14019ed98953SRafael J. Wysocki * 14029ed98953SRafael J. Wysocki * Persistent links stay around, but their status is changed to "available", 14039ed98953SRafael J. Wysocki * unless they already are in the "supplier unbind in progress" state in which 14049ed98953SRafael J. Wysocki * case they need not be updated. 14059ed98953SRafael J. Wysocki * 1406515db266SRafael J. Wysocki * Links without the DL_FLAG_MANAGED flag set are ignored. 14079ed98953SRafael J. Wysocki */ 14089ed98953SRafael J. Wysocki static void __device_links_no_driver(struct device *dev) 14099ed98953SRafael J. Wysocki { 14109ed98953SRafael J. Wysocki struct device_link *link, *ln; 14119ed98953SRafael J. Wysocki 14129ed98953SRafael J. Wysocki list_for_each_entry_safe_reverse(link, ln, &dev->links.suppliers, c_node) { 1413515db266SRafael J. Wysocki if (!(link->flags & DL_FLAG_MANAGED)) 14149ed98953SRafael J. Wysocki continue; 14159ed98953SRafael J. Wysocki 14168c3e315dSSaravana Kannan if (link->flags & DL_FLAG_AUTOREMOVE_CONSUMER) { 1417515db266SRafael J. Wysocki device_link_drop_managed(link); 14188c3e315dSSaravana Kannan continue; 14198c3e315dSSaravana Kannan } 14208c3e315dSSaravana Kannan 14218c3e315dSSaravana Kannan if (link->status != DL_STATE_CONSUMER_PROBE && 14228c3e315dSSaravana Kannan link->status != DL_STATE_ACTIVE) 14238c3e315dSSaravana Kannan continue; 14248c3e315dSSaravana Kannan 14258c3e315dSSaravana Kannan if (link->supplier->links.status == DL_DEV_DRIVER_BOUND) { 14269ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_AVAILABLE); 14278c3e315dSSaravana Kannan } else { 14288c3e315dSSaravana Kannan WARN_ON(!(link->flags & DL_FLAG_SYNC_STATE_ONLY)); 14298c3e315dSSaravana Kannan WRITE_ONCE(link->status, DL_STATE_DORMANT); 14308c3e315dSSaravana Kannan } 14319ed98953SRafael J. Wysocki } 14329ed98953SRafael J. Wysocki 14339ed98953SRafael J. Wysocki dev->links.status = DL_DEV_NO_DRIVER; 14349ed98953SRafael J. Wysocki } 14359ed98953SRafael J. Wysocki 143615cfb094SRafael J. Wysocki /** 143715cfb094SRafael J. Wysocki * device_links_no_driver - Update links after failing driver probe. 143815cfb094SRafael J. Wysocki * @dev: Device whose driver has just failed to probe. 143915cfb094SRafael J. Wysocki * 144015cfb094SRafael J. Wysocki * Clean up leftover links to consumers for @dev and invoke 144115cfb094SRafael J. Wysocki * %__device_links_no_driver() to update links to suppliers for it as 144215cfb094SRafael J. Wysocki * appropriate. 144315cfb094SRafael J. Wysocki * 1444515db266SRafael J. Wysocki * Links without the DL_FLAG_MANAGED flag set are ignored. 144515cfb094SRafael J. Wysocki */ 14469ed98953SRafael J. Wysocki void device_links_no_driver(struct device *dev) 14479ed98953SRafael J. Wysocki { 144815cfb094SRafael J. Wysocki struct device_link *link; 144915cfb094SRafael J. Wysocki 14509ed98953SRafael J. Wysocki device_links_write_lock(); 145115cfb094SRafael J. Wysocki 145215cfb094SRafael J. Wysocki list_for_each_entry(link, &dev->links.consumers, s_node) { 1453515db266SRafael J. Wysocki if (!(link->flags & DL_FLAG_MANAGED)) 145415cfb094SRafael J. Wysocki continue; 145515cfb094SRafael J. Wysocki 145615cfb094SRafael J. Wysocki /* 145715cfb094SRafael J. Wysocki * The probe has failed, so if the status of the link is 145815cfb094SRafael J. Wysocki * "consumer probe" or "active", it must have been added by 145915cfb094SRafael J. Wysocki * a probing consumer while this device was still probing. 146015cfb094SRafael J. Wysocki * Change its state to "dormant", as it represents a valid 146115cfb094SRafael J. Wysocki * relationship, but it is not functionally meaningful. 146215cfb094SRafael J. Wysocki */ 146315cfb094SRafael J. Wysocki if (link->status == DL_STATE_CONSUMER_PROBE || 146415cfb094SRafael J. Wysocki link->status == DL_STATE_ACTIVE) 146515cfb094SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_DORMANT); 146615cfb094SRafael J. Wysocki } 146715cfb094SRafael J. Wysocki 14689ed98953SRafael J. Wysocki __device_links_no_driver(dev); 146915cfb094SRafael J. Wysocki 14709ed98953SRafael J. Wysocki device_links_write_unlock(); 14719ed98953SRafael J. Wysocki } 14729ed98953SRafael J. Wysocki 14739ed98953SRafael J. Wysocki /** 14749ed98953SRafael J. Wysocki * device_links_driver_cleanup - Update links after driver removal. 14759ed98953SRafael J. Wysocki * @dev: Device whose driver has just gone away. 14769ed98953SRafael J. Wysocki * 14779ed98953SRafael J. Wysocki * Update links to consumers for @dev by changing their status to "dormant" and 14789ed98953SRafael J. Wysocki * invoke %__device_links_no_driver() to update links to suppliers for it as 14799ed98953SRafael J. Wysocki * appropriate. 14809ed98953SRafael J. Wysocki * 1481515db266SRafael J. Wysocki * Links without the DL_FLAG_MANAGED flag set are ignored. 14829ed98953SRafael J. Wysocki */ 14839ed98953SRafael J. Wysocki void device_links_driver_cleanup(struct device *dev) 14849ed98953SRafael J. Wysocki { 1485c8d50986SRafael J. Wysocki struct device_link *link, *ln; 14869ed98953SRafael J. Wysocki 14879ed98953SRafael J. Wysocki device_links_write_lock(); 14889ed98953SRafael J. Wysocki 1489c8d50986SRafael J. Wysocki list_for_each_entry_safe(link, ln, &dev->links.consumers, s_node) { 1490515db266SRafael J. Wysocki if (!(link->flags & DL_FLAG_MANAGED)) 14919ed98953SRafael J. Wysocki continue; 14929ed98953SRafael J. Wysocki 1493e88728f4SVivek Gautam WARN_ON(link->flags & DL_FLAG_AUTOREMOVE_CONSUMER); 14949ed98953SRafael J. Wysocki WARN_ON(link->status != DL_STATE_SUPPLIER_UNBIND); 14951689cac5SVivek Gautam 14961689cac5SVivek Gautam /* 14971689cac5SVivek Gautam * autoremove the links between this @dev and its consumer 14981689cac5SVivek Gautam * devices that are not active, i.e. where the link state 14991689cac5SVivek Gautam * has moved to DL_STATE_SUPPLIER_UNBIND. 15001689cac5SVivek Gautam */ 15011689cac5SVivek Gautam if (link->status == DL_STATE_SUPPLIER_UNBIND && 15021689cac5SVivek Gautam link->flags & DL_FLAG_AUTOREMOVE_SUPPLIER) 1503515db266SRafael J. Wysocki device_link_drop_managed(link); 15041689cac5SVivek Gautam 15059ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_DORMANT); 15069ed98953SRafael J. Wysocki } 15079ed98953SRafael J. Wysocki 15083b052a3eSSaravana Kannan list_del_init(&dev->links.defer_sync); 15099ed98953SRafael J. Wysocki __device_links_no_driver(dev); 15109ed98953SRafael J. Wysocki 15119ed98953SRafael J. Wysocki device_links_write_unlock(); 15129ed98953SRafael J. Wysocki } 15139ed98953SRafael J. Wysocki 15149ed98953SRafael J. Wysocki /** 15159ed98953SRafael J. Wysocki * device_links_busy - Check if there are any busy links to consumers. 15169ed98953SRafael J. Wysocki * @dev: Device to check. 15179ed98953SRafael J. Wysocki * 15189ed98953SRafael J. Wysocki * Check each consumer of the device and return 'true' if its link's status 15199ed98953SRafael J. Wysocki * is one of "consumer probe" or "active" (meaning that the given consumer is 15209ed98953SRafael J. Wysocki * probing right now or its driver is present). Otherwise, change the link 15219ed98953SRafael J. Wysocki * state to "supplier unbind" to prevent the consumer from being probed 15229ed98953SRafael J. Wysocki * successfully going forward. 15239ed98953SRafael J. Wysocki * 15249ed98953SRafael J. Wysocki * Return 'false' if there are no probing or active consumers. 15259ed98953SRafael J. Wysocki * 1526515db266SRafael J. Wysocki * Links without the DL_FLAG_MANAGED flag set are ignored. 15279ed98953SRafael J. Wysocki */ 15289ed98953SRafael J. Wysocki bool device_links_busy(struct device *dev) 15299ed98953SRafael J. Wysocki { 15309ed98953SRafael J. Wysocki struct device_link *link; 15319ed98953SRafael J. Wysocki bool ret = false; 15329ed98953SRafael J. Wysocki 15339ed98953SRafael J. Wysocki device_links_write_lock(); 15349ed98953SRafael J. Wysocki 15359ed98953SRafael J. Wysocki list_for_each_entry(link, &dev->links.consumers, s_node) { 1536515db266SRafael J. Wysocki if (!(link->flags & DL_FLAG_MANAGED)) 15379ed98953SRafael J. Wysocki continue; 15389ed98953SRafael J. Wysocki 15399ed98953SRafael J. Wysocki if (link->status == DL_STATE_CONSUMER_PROBE 15409ed98953SRafael J. Wysocki || link->status == DL_STATE_ACTIVE) { 15419ed98953SRafael J. Wysocki ret = true; 15429ed98953SRafael J. Wysocki break; 15439ed98953SRafael J. Wysocki } 15449ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_SUPPLIER_UNBIND); 15459ed98953SRafael J. Wysocki } 15469ed98953SRafael J. Wysocki 15479ed98953SRafael J. Wysocki dev->links.status = DL_DEV_UNBINDING; 15489ed98953SRafael J. Wysocki 15499ed98953SRafael J. Wysocki device_links_write_unlock(); 15509ed98953SRafael J. Wysocki return ret; 15519ed98953SRafael J. Wysocki } 15529ed98953SRafael J. Wysocki 15539ed98953SRafael J. Wysocki /** 15549ed98953SRafael J. Wysocki * device_links_unbind_consumers - Force unbind consumers of the given device. 15559ed98953SRafael J. Wysocki * @dev: Device to unbind the consumers of. 15569ed98953SRafael J. Wysocki * 15579ed98953SRafael J. Wysocki * Walk the list of links to consumers for @dev and if any of them is in the 15589ed98953SRafael J. Wysocki * "consumer probe" state, wait for all device probes in progress to complete 15599ed98953SRafael J. Wysocki * and start over. 15609ed98953SRafael J. Wysocki * 15619ed98953SRafael J. Wysocki * If that's not the case, change the status of the link to "supplier unbind" 15629ed98953SRafael J. Wysocki * and check if the link was in the "active" state. If so, force the consumer 15639ed98953SRafael J. Wysocki * driver to unbind and start over (the consumer will not re-probe as we have 15649ed98953SRafael J. Wysocki * changed the state of the link already). 15659ed98953SRafael J. Wysocki * 1566515db266SRafael J. Wysocki * Links without the DL_FLAG_MANAGED flag set are ignored. 15679ed98953SRafael J. Wysocki */ 15689ed98953SRafael J. Wysocki void device_links_unbind_consumers(struct device *dev) 15699ed98953SRafael J. Wysocki { 15709ed98953SRafael J. Wysocki struct device_link *link; 15719ed98953SRafael J. Wysocki 15729ed98953SRafael J. Wysocki start: 15739ed98953SRafael J. Wysocki device_links_write_lock(); 15749ed98953SRafael J. Wysocki 15759ed98953SRafael J. Wysocki list_for_each_entry(link, &dev->links.consumers, s_node) { 15769ed98953SRafael J. Wysocki enum device_link_state status; 15779ed98953SRafael J. Wysocki 157805ef983eSSaravana Kannan if (!(link->flags & DL_FLAG_MANAGED) || 157905ef983eSSaravana Kannan link->flags & DL_FLAG_SYNC_STATE_ONLY) 15809ed98953SRafael J. Wysocki continue; 15819ed98953SRafael J. Wysocki 15829ed98953SRafael J. Wysocki status = link->status; 15839ed98953SRafael J. Wysocki if (status == DL_STATE_CONSUMER_PROBE) { 15849ed98953SRafael J. Wysocki device_links_write_unlock(); 15859ed98953SRafael J. Wysocki 15869ed98953SRafael J. Wysocki wait_for_device_probe(); 15879ed98953SRafael J. Wysocki goto start; 15889ed98953SRafael J. Wysocki } 15899ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_SUPPLIER_UNBIND); 15909ed98953SRafael J. Wysocki if (status == DL_STATE_ACTIVE) { 15919ed98953SRafael J. Wysocki struct device *consumer = link->consumer; 15929ed98953SRafael J. Wysocki 15939ed98953SRafael J. Wysocki get_device(consumer); 15949ed98953SRafael J. Wysocki 15959ed98953SRafael J. Wysocki device_links_write_unlock(); 15969ed98953SRafael J. Wysocki 15979ed98953SRafael J. Wysocki device_release_driver_internal(consumer, NULL, 15989ed98953SRafael J. Wysocki consumer->parent); 15999ed98953SRafael J. Wysocki put_device(consumer); 16009ed98953SRafael J. Wysocki goto start; 16019ed98953SRafael J. Wysocki } 16029ed98953SRafael J. Wysocki } 16039ed98953SRafael J. Wysocki 16049ed98953SRafael J. Wysocki device_links_write_unlock(); 16059ed98953SRafael J. Wysocki } 16069ed98953SRafael J. Wysocki 16079ed98953SRafael J. Wysocki /** 16089ed98953SRafael J. Wysocki * device_links_purge - Delete existing links to other devices. 16099ed98953SRafael J. Wysocki * @dev: Target device. 16109ed98953SRafael J. Wysocki */ 16119ed98953SRafael J. Wysocki static void device_links_purge(struct device *dev) 16129ed98953SRafael J. Wysocki { 16139ed98953SRafael J. Wysocki struct device_link *link, *ln; 16149ed98953SRafael J. Wysocki 1615287905e6SSaravana Kannan if (dev->class == &devlink_class) 1616287905e6SSaravana Kannan return; 1617287905e6SSaravana Kannan 16189ed98953SRafael J. Wysocki /* 16199ed98953SRafael J. Wysocki * Delete all of the remaining links from this device to any other 16209ed98953SRafael J. Wysocki * devices (either consumers or suppliers). 16219ed98953SRafael J. Wysocki */ 16229ed98953SRafael J. Wysocki device_links_write_lock(); 16239ed98953SRafael J. Wysocki 16249ed98953SRafael J. Wysocki list_for_each_entry_safe_reverse(link, ln, &dev->links.suppliers, c_node) { 16259ed98953SRafael J. Wysocki WARN_ON(link->status == DL_STATE_ACTIVE); 1626ead18c23SLukas Wunner __device_link_del(&link->kref); 16279ed98953SRafael J. Wysocki } 16289ed98953SRafael J. Wysocki 16299ed98953SRafael J. Wysocki list_for_each_entry_safe_reverse(link, ln, &dev->links.consumers, s_node) { 16309ed98953SRafael J. Wysocki WARN_ON(link->status != DL_STATE_DORMANT && 16319ed98953SRafael J. Wysocki link->status != DL_STATE_NONE); 1632ead18c23SLukas Wunner __device_link_del(&link->kref); 16339ed98953SRafael J. Wysocki } 16349ed98953SRafael J. Wysocki 16359ed98953SRafael J. Wysocki device_links_write_unlock(); 16369ed98953SRafael J. Wysocki } 16379ed98953SRafael J. Wysocki 1638b90fb8f6SSaravana Kannan #define FW_DEVLINK_FLAGS_PERMISSIVE (DL_FLAG_INFERRED | \ 1639b90fb8f6SSaravana Kannan DL_FLAG_SYNC_STATE_ONLY) 1640b90fb8f6SSaravana Kannan #define FW_DEVLINK_FLAGS_ON (DL_FLAG_INFERRED | \ 1641b90fb8f6SSaravana Kannan DL_FLAG_AUTOPROBE_CONSUMER) 1642b90fb8f6SSaravana Kannan #define FW_DEVLINK_FLAGS_RPM (FW_DEVLINK_FLAGS_ON | \ 1643b90fb8f6SSaravana Kannan DL_FLAG_PM_RUNTIME) 1644b90fb8f6SSaravana Kannan 1645ea718c69SSaravana Kannan static u32 fw_devlink_flags = FW_DEVLINK_FLAGS_ON; 164642926ac3SSaravana Kannan static int __init fw_devlink_setup(char *arg) 164742926ac3SSaravana Kannan { 164842926ac3SSaravana Kannan if (!arg) 164942926ac3SSaravana Kannan return -EINVAL; 165042926ac3SSaravana Kannan 165142926ac3SSaravana Kannan if (strcmp(arg, "off") == 0) { 165242926ac3SSaravana Kannan fw_devlink_flags = 0; 165342926ac3SSaravana Kannan } else if (strcmp(arg, "permissive") == 0) { 1654b90fb8f6SSaravana Kannan fw_devlink_flags = FW_DEVLINK_FLAGS_PERMISSIVE; 165542926ac3SSaravana Kannan } else if (strcmp(arg, "on") == 0) { 1656b90fb8f6SSaravana Kannan fw_devlink_flags = FW_DEVLINK_FLAGS_ON; 165742926ac3SSaravana Kannan } else if (strcmp(arg, "rpm") == 0) { 1658b90fb8f6SSaravana Kannan fw_devlink_flags = FW_DEVLINK_FLAGS_RPM; 165942926ac3SSaravana Kannan } 166042926ac3SSaravana Kannan return 0; 166142926ac3SSaravana Kannan } 166242926ac3SSaravana Kannan early_param("fw_devlink", fw_devlink_setup); 166342926ac3SSaravana Kannan 1664d8ab4685SGreg Kroah-Hartman static bool fw_devlink_strict; 166519d0f5f6SSaravana Kannan static int __init fw_devlink_strict_setup(char *arg) 166619d0f5f6SSaravana Kannan { 166773060022SChristophe JAILLET return kstrtobool(arg, &fw_devlink_strict); 166819d0f5f6SSaravana Kannan } 166919d0f5f6SSaravana Kannan early_param("fw_devlink.strict", fw_devlink_strict_setup); 167019d0f5f6SSaravana Kannan 1671ffbe08a8SSaravana Kannan #define FW_DEVLINK_SYNC_STATE_STRICT 0 1672ffbe08a8SSaravana Kannan #define FW_DEVLINK_SYNC_STATE_TIMEOUT 1 1673ffbe08a8SSaravana Kannan 16748ad266d1SSaravana Kannan #ifndef CONFIG_FW_DEVLINK_SYNC_STATE_TIMEOUT 1675ffbe08a8SSaravana Kannan static int fw_devlink_sync_state; 16768ad266d1SSaravana Kannan #else 16778ad266d1SSaravana Kannan static int fw_devlink_sync_state = FW_DEVLINK_SYNC_STATE_TIMEOUT; 16788ad266d1SSaravana Kannan #endif 16798ad266d1SSaravana Kannan 1680ffbe08a8SSaravana Kannan static int __init fw_devlink_sync_state_setup(char *arg) 1681ffbe08a8SSaravana Kannan { 1682ffbe08a8SSaravana Kannan if (!arg) 1683ffbe08a8SSaravana Kannan return -EINVAL; 1684ffbe08a8SSaravana Kannan 1685ffbe08a8SSaravana Kannan if (strcmp(arg, "strict") == 0) { 1686ffbe08a8SSaravana Kannan fw_devlink_sync_state = FW_DEVLINK_SYNC_STATE_STRICT; 1687ffbe08a8SSaravana Kannan return 0; 1688ffbe08a8SSaravana Kannan } else if (strcmp(arg, "timeout") == 0) { 1689ffbe08a8SSaravana Kannan fw_devlink_sync_state = FW_DEVLINK_SYNC_STATE_TIMEOUT; 1690ffbe08a8SSaravana Kannan return 0; 1691ffbe08a8SSaravana Kannan } 1692ffbe08a8SSaravana Kannan return -EINVAL; 1693ffbe08a8SSaravana Kannan } 1694ffbe08a8SSaravana Kannan early_param("fw_devlink.sync_state", fw_devlink_sync_state_setup); 1695ffbe08a8SSaravana Kannan 1696cd115c04SSaravana Kannan static inline u32 fw_devlink_get_flags(u8 fwlink_flags) 169742926ac3SSaravana Kannan { 1698cd115c04SSaravana Kannan if (fwlink_flags & FWLINK_FLAG_CYCLE) 1699cd115c04SSaravana Kannan return FW_DEVLINK_FLAGS_PERMISSIVE | DL_FLAG_CYCLE; 1700cd115c04SSaravana Kannan 170142926ac3SSaravana Kannan return fw_devlink_flags; 170242926ac3SSaravana Kannan } 170342926ac3SSaravana Kannan 170442926ac3SSaravana Kannan static bool fw_devlink_is_permissive(void) 170542926ac3SSaravana Kannan { 1706b90fb8f6SSaravana Kannan return fw_devlink_flags == FW_DEVLINK_FLAGS_PERMISSIVE; 170742926ac3SSaravana Kannan } 170842926ac3SSaravana Kannan 170919d0f5f6SSaravana Kannan bool fw_devlink_is_strict(void) 171019d0f5f6SSaravana Kannan { 171119d0f5f6SSaravana Kannan return fw_devlink_strict && !fw_devlink_is_permissive(); 17129ed98953SRafael J. Wysocki } 17139ed98953SRafael J. Wysocki 1714c2c724c8SSaravana Kannan static void fw_devlink_parse_fwnode(struct fwnode_handle *fwnode) 1715c2c724c8SSaravana Kannan { 1716c2c724c8SSaravana Kannan if (fwnode->flags & FWNODE_FLAG_LINKS_ADDED) 1717c2c724c8SSaravana Kannan return; 1718c2c724c8SSaravana Kannan 17192d09e6ebSSaravana Kannan fwnode_call_int_op(fwnode, add_links); 1720c2c724c8SSaravana Kannan fwnode->flags |= FWNODE_FLAG_LINKS_ADDED; 1721c2c724c8SSaravana Kannan } 1722c2c724c8SSaravana Kannan 1723c2c724c8SSaravana Kannan static void fw_devlink_parse_fwtree(struct fwnode_handle *fwnode) 1724c2c724c8SSaravana Kannan { 1725c2c724c8SSaravana Kannan struct fwnode_handle *child = NULL; 1726c2c724c8SSaravana Kannan 1727c2c724c8SSaravana Kannan fw_devlink_parse_fwnode(fwnode); 1728c2c724c8SSaravana Kannan 1729c2c724c8SSaravana Kannan while ((child = fwnode_get_next_available_child_node(fwnode, child))) 1730c2c724c8SSaravana Kannan fw_devlink_parse_fwtree(child); 1731c2c724c8SSaravana Kannan } 1732c2c724c8SSaravana Kannan 1733d46f3e3eSSaravana Kannan static void fw_devlink_relax_link(struct device_link *link) 1734d46f3e3eSSaravana Kannan { 1735d46f3e3eSSaravana Kannan if (!(link->flags & DL_FLAG_INFERRED)) 1736d46f3e3eSSaravana Kannan return; 1737d46f3e3eSSaravana Kannan 173867cad5c6SSaravana Kannan if (device_link_flag_is_sync_state_only(link->flags)) 1739d46f3e3eSSaravana Kannan return; 1740d46f3e3eSSaravana Kannan 1741d46f3e3eSSaravana Kannan pm_runtime_drop_link(link); 1742d46f3e3eSSaravana Kannan link->flags = DL_FLAG_MANAGED | FW_DEVLINK_FLAGS_PERMISSIVE; 1743d46f3e3eSSaravana Kannan dev_dbg(link->consumer, "Relaxing link with %s\n", 1744d46f3e3eSSaravana Kannan dev_name(link->supplier)); 1745d46f3e3eSSaravana Kannan } 1746d46f3e3eSSaravana Kannan 1747d46f3e3eSSaravana Kannan static int fw_devlink_no_driver(struct device *dev, void *data) 1748d46f3e3eSSaravana Kannan { 1749d46f3e3eSSaravana Kannan struct device_link *link = to_devlink(dev); 1750d46f3e3eSSaravana Kannan 1751d46f3e3eSSaravana Kannan if (!link->supplier->can_match) 1752d46f3e3eSSaravana Kannan fw_devlink_relax_link(link); 1753d46f3e3eSSaravana Kannan 1754d46f3e3eSSaravana Kannan return 0; 1755d46f3e3eSSaravana Kannan } 1756d46f3e3eSSaravana Kannan 1757d46f3e3eSSaravana Kannan void fw_devlink_drivers_done(void) 1758d46f3e3eSSaravana Kannan { 1759d46f3e3eSSaravana Kannan fw_devlink_drv_reg_done = true; 1760d46f3e3eSSaravana Kannan device_links_write_lock(); 1761d46f3e3eSSaravana Kannan class_for_each_device(&devlink_class, NULL, NULL, 1762d46f3e3eSSaravana Kannan fw_devlink_no_driver); 1763d46f3e3eSSaravana Kannan device_links_write_unlock(); 1764d46f3e3eSSaravana Kannan } 1765d46f3e3eSSaravana Kannan 1766ffbe08a8SSaravana Kannan static int fw_devlink_dev_sync_state(struct device *dev, void *data) 1767ffbe08a8SSaravana Kannan { 1768ffbe08a8SSaravana Kannan struct device_link *link = to_devlink(dev); 1769ffbe08a8SSaravana Kannan struct device *sup = link->supplier; 1770ffbe08a8SSaravana Kannan 1771ffbe08a8SSaravana Kannan if (!(link->flags & DL_FLAG_MANAGED) || 1772ffbe08a8SSaravana Kannan link->status == DL_STATE_ACTIVE || sup->state_synced || 1773ffbe08a8SSaravana Kannan !dev_has_sync_state(sup)) 1774ffbe08a8SSaravana Kannan return 0; 1775ffbe08a8SSaravana Kannan 1776ffbe08a8SSaravana Kannan if (fw_devlink_sync_state == FW_DEVLINK_SYNC_STATE_STRICT) { 1777ffbe08a8SSaravana Kannan dev_warn(sup, "sync_state() pending due to %s\n", 1778ffbe08a8SSaravana Kannan dev_name(link->consumer)); 1779ffbe08a8SSaravana Kannan return 0; 1780ffbe08a8SSaravana Kannan } 1781ffbe08a8SSaravana Kannan 1782ffbe08a8SSaravana Kannan if (!list_empty(&sup->links.defer_sync)) 1783ffbe08a8SSaravana Kannan return 0; 1784ffbe08a8SSaravana Kannan 1785ffbe08a8SSaravana Kannan dev_warn(sup, "Timed out. Forcing sync_state()\n"); 1786ffbe08a8SSaravana Kannan sup->state_synced = true; 1787ffbe08a8SSaravana Kannan get_device(sup); 1788ffbe08a8SSaravana Kannan list_add_tail(&sup->links.defer_sync, data); 1789ffbe08a8SSaravana Kannan 1790ffbe08a8SSaravana Kannan return 0; 1791ffbe08a8SSaravana Kannan } 1792ffbe08a8SSaravana Kannan 1793ffbe08a8SSaravana Kannan void fw_devlink_probing_done(void) 1794ffbe08a8SSaravana Kannan { 1795ffbe08a8SSaravana Kannan LIST_HEAD(sync_list); 1796ffbe08a8SSaravana Kannan 1797ffbe08a8SSaravana Kannan device_links_write_lock(); 1798ffbe08a8SSaravana Kannan class_for_each_device(&devlink_class, NULL, &sync_list, 1799ffbe08a8SSaravana Kannan fw_devlink_dev_sync_state); 1800ffbe08a8SSaravana Kannan device_links_write_unlock(); 1801ffbe08a8SSaravana Kannan device_links_flush_sync_list(&sync_list, NULL); 1802ffbe08a8SSaravana Kannan } 1803ffbe08a8SSaravana Kannan 18042f8c3ae8SSaravana Kannan /** 18052f8c3ae8SSaravana Kannan * wait_for_init_devices_probe - Try to probe any device needed for init 18062f8c3ae8SSaravana Kannan * 18072f8c3ae8SSaravana Kannan * Some devices might need to be probed and bound successfully before the kernel 18082f8c3ae8SSaravana Kannan * boot sequence can finish and move on to init/userspace. For example, a 18092f8c3ae8SSaravana Kannan * network interface might need to be bound to be able to mount a NFS rootfs. 18102f8c3ae8SSaravana Kannan * 18112f8c3ae8SSaravana Kannan * With fw_devlink=on by default, some of these devices might be blocked from 18122f8c3ae8SSaravana Kannan * probing because they are waiting on a optional supplier that doesn't have a 18132f8c3ae8SSaravana Kannan * driver. While fw_devlink will eventually identify such devices and unblock 18142f8c3ae8SSaravana Kannan * the probing automatically, it might be too late by the time it unblocks the 18152f8c3ae8SSaravana Kannan * probing of devices. For example, the IP4 autoconfig might timeout before 18162f8c3ae8SSaravana Kannan * fw_devlink unblocks probing of the network interface. 18172f8c3ae8SSaravana Kannan * 18182f8c3ae8SSaravana Kannan * This function is available to temporarily try and probe all devices that have 18192f8c3ae8SSaravana Kannan * a driver even if some of their suppliers haven't been added or don't have 18202f8c3ae8SSaravana Kannan * drivers. 18212f8c3ae8SSaravana Kannan * 18222f8c3ae8SSaravana Kannan * The drivers can then decide which of the suppliers are optional vs mandatory 18232f8c3ae8SSaravana Kannan * and probe the device if possible. By the time this function returns, all such 18242f8c3ae8SSaravana Kannan * "best effort" probes are guaranteed to be completed. If a device successfully 18252f8c3ae8SSaravana Kannan * probes in this mode, we delete all fw_devlink discovered dependencies of that 18262f8c3ae8SSaravana Kannan * device where the supplier hasn't yet probed successfully because they have to 18272f8c3ae8SSaravana Kannan * be optional dependencies. 18282f8c3ae8SSaravana Kannan * 18292f8c3ae8SSaravana Kannan * Any devices that didn't successfully probe go back to being treated as if 18302f8c3ae8SSaravana Kannan * this function was never called. 18312f8c3ae8SSaravana Kannan * 18322f8c3ae8SSaravana Kannan * This also means that some devices that aren't needed for init and could have 18332f8c3ae8SSaravana Kannan * waited for their optional supplier to probe (when the supplier's module is 18342f8c3ae8SSaravana Kannan * loaded later on) would end up probing prematurely with limited functionality. 18352f8c3ae8SSaravana Kannan * So call this function only when boot would fail without it. 18362f8c3ae8SSaravana Kannan */ 18372f8c3ae8SSaravana Kannan void __init wait_for_init_devices_probe(void) 18382f8c3ae8SSaravana Kannan { 18392f8c3ae8SSaravana Kannan if (!fw_devlink_flags || fw_devlink_is_permissive()) 18402f8c3ae8SSaravana Kannan return; 18412f8c3ae8SSaravana Kannan 18422f8c3ae8SSaravana Kannan /* 18432f8c3ae8SSaravana Kannan * Wait for all ongoing probes to finish so that the "best effort" is 18442f8c3ae8SSaravana Kannan * only applied to devices that can't probe otherwise. 18452f8c3ae8SSaravana Kannan */ 18462f8c3ae8SSaravana Kannan wait_for_device_probe(); 18472f8c3ae8SSaravana Kannan 18482f8c3ae8SSaravana Kannan pr_info("Trying to probe devices needed for running init ...\n"); 18492f8c3ae8SSaravana Kannan fw_devlink_best_effort = true; 18502f8c3ae8SSaravana Kannan driver_deferred_probe_trigger(); 18512f8c3ae8SSaravana Kannan 18522f8c3ae8SSaravana Kannan /* 18532f8c3ae8SSaravana Kannan * Wait for all "best effort" probes to finish before going back to 18542f8c3ae8SSaravana Kannan * normal enforcement. 18552f8c3ae8SSaravana Kannan */ 18562f8c3ae8SSaravana Kannan wait_for_device_probe(); 18572f8c3ae8SSaravana Kannan fw_devlink_best_effort = false; 18582f8c3ae8SSaravana Kannan } 18592f8c3ae8SSaravana Kannan 1860d46f3e3eSSaravana Kannan static void fw_devlink_unblock_consumers(struct device *dev) 1861d46f3e3eSSaravana Kannan { 1862d46f3e3eSSaravana Kannan struct device_link *link; 1863d46f3e3eSSaravana Kannan 1864d46f3e3eSSaravana Kannan if (!fw_devlink_flags || fw_devlink_is_permissive()) 1865d46f3e3eSSaravana Kannan return; 1866d46f3e3eSSaravana Kannan 1867d46f3e3eSSaravana Kannan device_links_write_lock(); 1868d46f3e3eSSaravana Kannan list_for_each_entry(link, &dev->links.consumers, s_node) 1869d46f3e3eSSaravana Kannan fw_devlink_relax_link(link); 1870d46f3e3eSSaravana Kannan device_links_write_unlock(); 1871d46f3e3eSSaravana Kannan } 1872d46f3e3eSSaravana Kannan 1873b0e2fa4fSSaravana Kannan 1874411c0d58SSaravana Kannan static bool fwnode_init_without_drv(struct fwnode_handle *fwnode) 1875b0e2fa4fSSaravana Kannan { 1876411c0d58SSaravana Kannan struct device *dev; 1877411c0d58SSaravana Kannan bool ret; 1878b0e2fa4fSSaravana Kannan 1879411c0d58SSaravana Kannan if (!(fwnode->flags & FWNODE_FLAG_INITIALIZED)) 1880411c0d58SSaravana Kannan return false; 1881b0e2fa4fSSaravana Kannan 1882411c0d58SSaravana Kannan dev = get_dev_from_fwnode(fwnode); 1883411c0d58SSaravana Kannan ret = !dev || dev->links.status == DL_DEV_NO_DRIVER; 1884411c0d58SSaravana Kannan put_device(dev); 1885411c0d58SSaravana Kannan 1886b0e2fa4fSSaravana Kannan return ret; 1887b0e2fa4fSSaravana Kannan } 1888411c0d58SSaravana Kannan 1889411c0d58SSaravana Kannan static bool fwnode_ancestor_init_without_drv(struct fwnode_handle *fwnode) 1890411c0d58SSaravana Kannan { 1891411c0d58SSaravana Kannan struct fwnode_handle *parent; 1892411c0d58SSaravana Kannan 1893411c0d58SSaravana Kannan fwnode_for_each_parent_node(fwnode, parent) { 1894411c0d58SSaravana Kannan if (fwnode_init_without_drv(parent)) { 1895411c0d58SSaravana Kannan fwnode_handle_put(parent); 1896411c0d58SSaravana Kannan return true; 1897411c0d58SSaravana Kannan } 1898411c0d58SSaravana Kannan } 1899411c0d58SSaravana Kannan 1900411c0d58SSaravana Kannan return false; 1901411c0d58SSaravana Kannan } 1902411c0d58SSaravana Kannan 1903b0e2fa4fSSaravana Kannan /** 19043fb16866SSaravana Kannan * __fw_devlink_relax_cycles - Relax and mark dependency cycles. 19053fb16866SSaravana Kannan * @con: Potential consumer device. 19063fb16866SSaravana Kannan * @sup_handle: Potential supplier's fwnode. 19073fb16866SSaravana Kannan * 19083fb16866SSaravana Kannan * Needs to be called with fwnode_lock and device link lock held. 19093fb16866SSaravana Kannan * 19103fb16866SSaravana Kannan * Check if @sup_handle or any of its ancestors or suppliers direct/indirectly 19113fb16866SSaravana Kannan * depend on @con. This function can detect multiple cyles between @sup_handle 19123fb16866SSaravana Kannan * and @con. When such dependency cycles are found, convert all device links 19133fb16866SSaravana Kannan * created solely by fw_devlink into SYNC_STATE_ONLY device links. Also, mark 19143fb16866SSaravana Kannan * all fwnode links in the cycle with FWLINK_FLAG_CYCLE so that when they are 19153fb16866SSaravana Kannan * converted into a device link in the future, they are created as 19163fb16866SSaravana Kannan * SYNC_STATE_ONLY device links. This is the equivalent of doing 19173fb16866SSaravana Kannan * fw_devlink=permissive just between the devices in the cycle. We need to do 19183fb16866SSaravana Kannan * this because, at this point, fw_devlink can't tell which of these 19193fb16866SSaravana Kannan * dependencies is not a real dependency. 19203fb16866SSaravana Kannan * 19213fb16866SSaravana Kannan * Return true if one or more cycles were found. Otherwise, return false. 19223fb16866SSaravana Kannan */ 19233fb16866SSaravana Kannan static bool __fw_devlink_relax_cycles(struct device *con, 19243fb16866SSaravana Kannan struct fwnode_handle *sup_handle) 19253fb16866SSaravana Kannan { 19263fb16866SSaravana Kannan struct device *sup_dev = NULL, *par_dev = NULL; 19273fb16866SSaravana Kannan struct fwnode_link *link; 19283fb16866SSaravana Kannan struct device_link *dev_link; 19293fb16866SSaravana Kannan bool ret = false; 19303fb16866SSaravana Kannan 19313fb16866SSaravana Kannan if (!sup_handle) 19323fb16866SSaravana Kannan return false; 19333fb16866SSaravana Kannan 19343fb16866SSaravana Kannan /* 19353fb16866SSaravana Kannan * We aren't trying to find all cycles. Just a cycle between con and 19363fb16866SSaravana Kannan * sup_handle. 19373fb16866SSaravana Kannan */ 19383fb16866SSaravana Kannan if (sup_handle->flags & FWNODE_FLAG_VISITED) 19393fb16866SSaravana Kannan return false; 19403fb16866SSaravana Kannan 19413fb16866SSaravana Kannan sup_handle->flags |= FWNODE_FLAG_VISITED; 19423fb16866SSaravana Kannan 19433fb16866SSaravana Kannan sup_dev = get_dev_from_fwnode(sup_handle); 19443fb16866SSaravana Kannan 19453fb16866SSaravana Kannan /* Termination condition. */ 19463fb16866SSaravana Kannan if (sup_dev == con) { 19473fb16866SSaravana Kannan ret = true; 19483fb16866SSaravana Kannan goto out; 19493fb16866SSaravana Kannan } 19503fb16866SSaravana Kannan 19513fb16866SSaravana Kannan /* 19523fb16866SSaravana Kannan * If sup_dev is bound to a driver and @con hasn't started binding to a 19533fb16866SSaravana Kannan * driver, sup_dev can't be a consumer of @con. So, no need to check 19543fb16866SSaravana Kannan * further. 19553fb16866SSaravana Kannan */ 19563fb16866SSaravana Kannan if (sup_dev && sup_dev->links.status == DL_DEV_DRIVER_BOUND && 19573fb16866SSaravana Kannan con->links.status == DL_DEV_NO_DRIVER) { 19583fb16866SSaravana Kannan ret = false; 19593fb16866SSaravana Kannan goto out; 19603fb16866SSaravana Kannan } 19613fb16866SSaravana Kannan 19623fb16866SSaravana Kannan list_for_each_entry(link, &sup_handle->suppliers, c_hook) { 19633fb16866SSaravana Kannan if (__fw_devlink_relax_cycles(con, link->supplier)) { 19643fb16866SSaravana Kannan __fwnode_link_cycle(link); 19653fb16866SSaravana Kannan ret = true; 19663fb16866SSaravana Kannan } 19673fb16866SSaravana Kannan } 19683fb16866SSaravana Kannan 19693fb16866SSaravana Kannan /* 19703fb16866SSaravana Kannan * Give priority to device parent over fwnode parent to account for any 19713fb16866SSaravana Kannan * quirks in how fwnodes are converted to devices. 19723fb16866SSaravana Kannan */ 19733fb16866SSaravana Kannan if (sup_dev) 19743fb16866SSaravana Kannan par_dev = get_device(sup_dev->parent); 19753fb16866SSaravana Kannan else 19763fb16866SSaravana Kannan par_dev = fwnode_get_next_parent_dev(sup_handle); 19773fb16866SSaravana Kannan 19783fb16866SSaravana Kannan if (par_dev && __fw_devlink_relax_cycles(con, par_dev->fwnode)) 19793fb16866SSaravana Kannan ret = true; 19803fb16866SSaravana Kannan 19813fb16866SSaravana Kannan if (!sup_dev) 19823fb16866SSaravana Kannan goto out; 19833fb16866SSaravana Kannan 19843fb16866SSaravana Kannan list_for_each_entry(dev_link, &sup_dev->links.suppliers, c_node) { 19853fb16866SSaravana Kannan /* 19863fb16866SSaravana Kannan * Ignore a SYNC_STATE_ONLY flag only if it wasn't marked as 19873fb16866SSaravana Kannan * such due to a cycle. 19883fb16866SSaravana Kannan */ 19893fb16866SSaravana Kannan if (device_link_flag_is_sync_state_only(dev_link->flags) && 19903fb16866SSaravana Kannan !(dev_link->flags & DL_FLAG_CYCLE)) 19913fb16866SSaravana Kannan continue; 19923fb16866SSaravana Kannan 19933fb16866SSaravana Kannan if (__fw_devlink_relax_cycles(con, 19943fb16866SSaravana Kannan dev_link->supplier->fwnode)) { 19953fb16866SSaravana Kannan fw_devlink_relax_link(dev_link); 19963fb16866SSaravana Kannan dev_link->flags |= DL_FLAG_CYCLE; 19973fb16866SSaravana Kannan ret = true; 19983fb16866SSaravana Kannan } 19993fb16866SSaravana Kannan } 20003fb16866SSaravana Kannan 20013fb16866SSaravana Kannan out: 20023fb16866SSaravana Kannan sup_handle->flags &= ~FWNODE_FLAG_VISITED; 20033fb16866SSaravana Kannan put_device(sup_dev); 20043fb16866SSaravana Kannan put_device(par_dev); 20059ed98953SRafael J. Wysocki return ret; 20061da177e4SLinus Torvalds } 20071da177e4SLinus Torvalds 2008f9aa4606SSaravana Kannan /** 2009f9aa4606SSaravana Kannan * fw_devlink_create_devlink - Create a device link from a consumer to fwnode 201037c52f74SPierre-Louis Bossart * @con: consumer device for the device link 201137c52f74SPierre-Louis Bossart * @sup_handle: fwnode handle of supplier 2012cd115c04SSaravana Kannan * @link: fwnode link that's being converted to a device link 2013f9aa4606SSaravana Kannan * 2014f9aa4606SSaravana Kannan * This function will try to create a device link between the consumer device 2015f9aa4606SSaravana Kannan * @con and the supplier device represented by @sup_handle. 2016f9aa4606SSaravana Kannan * 2017f9aa4606SSaravana Kannan * The supplier has to be provided as a fwnode because incorrect cycles in 2018f9aa4606SSaravana Kannan * fwnode links can sometimes cause the supplier device to never be created. 2019f9aa4606SSaravana Kannan * This function detects such cases and returns an error if it cannot create a 2020f9aa4606SSaravana Kannan * device link from the consumer to a missing supplier. 2021f9aa4606SSaravana Kannan * 2022f9aa4606SSaravana Kannan * Returns, 2023f9aa4606SSaravana Kannan * 0 on successfully creating a device link 2024f9aa4606SSaravana Kannan * -EINVAL if the device link cannot be created as expected 2025f9aa4606SSaravana Kannan * -EAGAIN if the device link cannot be created right now, but it may be 2026f9aa4606SSaravana Kannan * possible to do that in the future 2027f9aa4606SSaravana Kannan */ 2028f9aa4606SSaravana Kannan static int fw_devlink_create_devlink(struct device *con, 2029cd115c04SSaravana Kannan struct fwnode_handle *sup_handle, 2030cd115c04SSaravana Kannan struct fwnode_link *link) 2031f9aa4606SSaravana Kannan { 2032f9aa4606SSaravana Kannan struct device *sup_dev; 2033f9aa4606SSaravana Kannan int ret = 0; 2034cd115c04SSaravana Kannan u32 flags; 2035cd115c04SSaravana Kannan 2036cd115c04SSaravana Kannan if (con->fwnode == link->consumer) 2037cd115c04SSaravana Kannan flags = fw_devlink_get_flags(link->flags); 2038cd115c04SSaravana Kannan else 2039cd115c04SSaravana Kannan flags = FW_DEVLINK_FLAGS_PERMISSIVE; 2040f9aa4606SSaravana Kannan 20415501765aSSaravana Kannan /* 20425501765aSSaravana Kannan * In some cases, a device P might also be a supplier to its child node 20435501765aSSaravana Kannan * C. However, this would defer the probe of C until the probe of P 20445501765aSSaravana Kannan * completes successfully. This is perfectly fine in the device driver 20455501765aSSaravana Kannan * model. device_add() doesn't guarantee probe completion of the device 20465501765aSSaravana Kannan * by the time it returns. 20475501765aSSaravana Kannan * 20485501765aSSaravana Kannan * However, there are a few drivers that assume C will finish probing 20495501765aSSaravana Kannan * as soon as it's added and before P finishes probing. So, we provide 20505501765aSSaravana Kannan * a flag to let fw_devlink know not to delay the probe of C until the 20515501765aSSaravana Kannan * probe of P completes successfully. 20525501765aSSaravana Kannan * 20535501765aSSaravana Kannan * When such a flag is set, we can't create device links where P is the 20545501765aSSaravana Kannan * supplier of C as that would delay the probe of C. 20555501765aSSaravana Kannan */ 20565501765aSSaravana Kannan if (sup_handle->flags & FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD && 20575501765aSSaravana Kannan fwnode_is_ancestor_of(sup_handle, con->fwnode)) 20585501765aSSaravana Kannan return -EINVAL; 20595501765aSSaravana Kannan 20603fb16866SSaravana Kannan /* 20613fb16866SSaravana Kannan * SYNC_STATE_ONLY device links don't block probing and supports cycles. 20623fb16866SSaravana Kannan * So cycle detection isn't necessary and shouldn't be done. 20633fb16866SSaravana Kannan */ 20643fb16866SSaravana Kannan if (!(flags & DL_FLAG_SYNC_STATE_ONLY)) { 20653fb16866SSaravana Kannan device_links_write_lock(); 20663fb16866SSaravana Kannan if (__fw_devlink_relax_cycles(con, sup_handle)) { 20673fb16866SSaravana Kannan __fwnode_link_cycle(link); 20683fb16866SSaravana Kannan flags = fw_devlink_get_flags(link->flags); 20693fb16866SSaravana Kannan dev_info(con, "Fixed dependency cycle(s) with %pfwf\n", 20703fb16866SSaravana Kannan sup_handle); 20713fb16866SSaravana Kannan } 20723fb16866SSaravana Kannan device_links_write_unlock(); 20733fb16866SSaravana Kannan } 20743fb16866SSaravana Kannan 20753a2dbc51SSaravana Kannan if (sup_handle->flags & FWNODE_FLAG_NOT_DEVICE) 20763a2dbc51SSaravana Kannan sup_dev = fwnode_get_next_parent_dev(sup_handle); 20773a2dbc51SSaravana Kannan else 2078f9aa4606SSaravana Kannan sup_dev = get_dev_from_fwnode(sup_handle); 20793a2dbc51SSaravana Kannan 2080f9aa4606SSaravana Kannan if (sup_dev) { 2081f9aa4606SSaravana Kannan /* 208274c782cfSSaravana Kannan * If it's one of those drivers that don't actually bind to 208374c782cfSSaravana Kannan * their device using driver core, then don't wait on this 208474c782cfSSaravana Kannan * supplier device indefinitely. 208574c782cfSSaravana Kannan */ 208674c782cfSSaravana Kannan if (sup_dev->links.status == DL_DEV_NO_DRIVER && 208774c782cfSSaravana Kannan sup_handle->flags & FWNODE_FLAG_INITIALIZED) { 20883fb16866SSaravana Kannan dev_dbg(con, 20893fb16866SSaravana Kannan "Not linking %pfwf - dev might never probe\n", 20903fb16866SSaravana Kannan sup_handle); 209174c782cfSSaravana Kannan ret = -EINVAL; 209274c782cfSSaravana Kannan goto out; 209374c782cfSSaravana Kannan } 209474c782cfSSaravana Kannan 209563098724SSaravana Kannan if (con != sup_dev && !device_link_add(con, sup_dev, flags)) { 209663098724SSaravana Kannan dev_err(con, "Failed to create device link (0x%x) with %s\n", 209763098724SSaravana Kannan flags, dev_name(sup_dev)); 2098f9aa4606SSaravana Kannan ret = -EINVAL; 2099b0e2fa4fSSaravana Kannan } 2100f9aa4606SSaravana Kannan 2101f9aa4606SSaravana Kannan goto out; 2102f9aa4606SSaravana Kannan } 2103f9aa4606SSaravana Kannan 2104411c0d58SSaravana Kannan /* 2105411c0d58SSaravana Kannan * Supplier or supplier's ancestor already initialized without a struct 2106411c0d58SSaravana Kannan * device or being probed by a driver. 2107411c0d58SSaravana Kannan */ 2108411c0d58SSaravana Kannan if (fwnode_init_without_drv(sup_handle) || 2109411c0d58SSaravana Kannan fwnode_ancestor_init_without_drv(sup_handle)) { 21103fb16866SSaravana Kannan dev_dbg(con, "Not linking %pfwf - might never become dev\n", 2111411c0d58SSaravana Kannan sup_handle); 211274c782cfSSaravana Kannan return -EINVAL; 2113f9aa4606SSaravana Kannan } 2114f9aa4606SSaravana Kannan 2115f9aa4606SSaravana Kannan ret = -EAGAIN; 2116f9aa4606SSaravana Kannan out: 2117f9aa4606SSaravana Kannan put_device(sup_dev); 2118f9aa4606SSaravana Kannan return ret; 2119f9aa4606SSaravana Kannan } 2120f9aa4606SSaravana Kannan 2121f9aa4606SSaravana Kannan /** 2122f9aa4606SSaravana Kannan * __fw_devlink_link_to_consumers - Create device links to consumers of a device 212337c52f74SPierre-Louis Bossart * @dev: Device that needs to be linked to its consumers 2124f9aa4606SSaravana Kannan * 2125f9aa4606SSaravana Kannan * This function looks at all the consumer fwnodes of @dev and creates device 2126f9aa4606SSaravana Kannan * links between the consumer device and @dev (supplier). 2127f9aa4606SSaravana Kannan * 2128f9aa4606SSaravana Kannan * If the consumer device has not been added yet, then this function creates a 2129f9aa4606SSaravana Kannan * SYNC_STATE_ONLY link between @dev (supplier) and the closest ancestor device 2130f9aa4606SSaravana Kannan * of the consumer fwnode. This is necessary to make sure @dev doesn't get a 2131f9aa4606SSaravana Kannan * sync_state() callback before the real consumer device gets to be added and 2132f9aa4606SSaravana Kannan * then probed. 2133f9aa4606SSaravana Kannan * 2134f9aa4606SSaravana Kannan * Once device links are created from the real consumer to @dev (supplier), the 2135f9aa4606SSaravana Kannan * fwnode links are deleted. 2136f9aa4606SSaravana Kannan */ 2137f9aa4606SSaravana Kannan static void __fw_devlink_link_to_consumers(struct device *dev) 2138f9aa4606SSaravana Kannan { 2139f9aa4606SSaravana Kannan struct fwnode_handle *fwnode = dev->fwnode; 2140f9aa4606SSaravana Kannan struct fwnode_link *link, *tmp; 2141f9aa4606SSaravana Kannan 2142f9aa4606SSaravana Kannan list_for_each_entry_safe(link, tmp, &fwnode->consumers, s_hook) { 2143f9aa4606SSaravana Kannan struct device *con_dev; 2144f9aa4606SSaravana Kannan bool own_link = true; 2145f9aa4606SSaravana Kannan int ret; 2146f9aa4606SSaravana Kannan 2147f9aa4606SSaravana Kannan con_dev = get_dev_from_fwnode(link->consumer); 2148f9aa4606SSaravana Kannan /* 2149f9aa4606SSaravana Kannan * If consumer device is not available yet, make a "proxy" 2150f9aa4606SSaravana Kannan * SYNC_STATE_ONLY link from the consumer's parent device to 2151f9aa4606SSaravana Kannan * the supplier device. This is necessary to make sure the 2152f9aa4606SSaravana Kannan * supplier doesn't get a sync_state() callback before the real 2153f9aa4606SSaravana Kannan * consumer can create a device link to the supplier. 2154f9aa4606SSaravana Kannan * 2155f9aa4606SSaravana Kannan * This proxy link step is needed to handle the case where the 2156f9aa4606SSaravana Kannan * consumer's parent device is added before the supplier. 2157f9aa4606SSaravana Kannan */ 2158f9aa4606SSaravana Kannan if (!con_dev) { 2159f9aa4606SSaravana Kannan con_dev = fwnode_get_next_parent_dev(link->consumer); 2160f9aa4606SSaravana Kannan /* 2161f9aa4606SSaravana Kannan * However, if the consumer's parent device is also the 2162f9aa4606SSaravana Kannan * parent of the supplier, don't create a 2163f9aa4606SSaravana Kannan * consumer-supplier link from the parent to its child 2164f9aa4606SSaravana Kannan * device. Such a dependency is impossible. 2165f9aa4606SSaravana Kannan */ 2166f9aa4606SSaravana Kannan if (con_dev && 2167f9aa4606SSaravana Kannan fwnode_is_ancestor_of(con_dev->fwnode, fwnode)) { 2168f9aa4606SSaravana Kannan put_device(con_dev); 2169f9aa4606SSaravana Kannan con_dev = NULL; 2170f9aa4606SSaravana Kannan } else { 2171f9aa4606SSaravana Kannan own_link = false; 2172f9aa4606SSaravana Kannan } 2173f9aa4606SSaravana Kannan } 2174f9aa4606SSaravana Kannan 2175f9aa4606SSaravana Kannan if (!con_dev) 2176f9aa4606SSaravana Kannan continue; 2177f9aa4606SSaravana Kannan 2178cd115c04SSaravana Kannan ret = fw_devlink_create_devlink(con_dev, fwnode, link); 2179f9aa4606SSaravana Kannan put_device(con_dev); 2180f9aa4606SSaravana Kannan if (!own_link || ret == -EAGAIN) 2181f9aa4606SSaravana Kannan continue; 2182f9aa4606SSaravana Kannan 218376f13081SSaravana Kannan __fwnode_link_del(link); 2184f9aa4606SSaravana Kannan } 2185f9aa4606SSaravana Kannan } 2186f9aa4606SSaravana Kannan 2187f9aa4606SSaravana Kannan /** 2188f9aa4606SSaravana Kannan * __fw_devlink_link_to_suppliers - Create device links to suppliers of a device 218937c52f74SPierre-Louis Bossart * @dev: The consumer device that needs to be linked to its suppliers 219037c52f74SPierre-Louis Bossart * @fwnode: Root of the fwnode tree that is used to create device links 2191f9aa4606SSaravana Kannan * 2192f9aa4606SSaravana Kannan * This function looks at all the supplier fwnodes of fwnode tree rooted at 2193f9aa4606SSaravana Kannan * @fwnode and creates device links between @dev (consumer) and all the 2194f9aa4606SSaravana Kannan * supplier devices of the entire fwnode tree at @fwnode. 2195f9aa4606SSaravana Kannan * 2196f9aa4606SSaravana Kannan * The function creates normal (non-SYNC_STATE_ONLY) device links between @dev 2197f9aa4606SSaravana Kannan * and the real suppliers of @dev. Once these device links are created, the 21983fb16866SSaravana Kannan * fwnode links are deleted. 2199f9aa4606SSaravana Kannan * 2200f9aa4606SSaravana Kannan * In addition, it also looks at all the suppliers of the entire fwnode tree 2201f9aa4606SSaravana Kannan * because some of the child devices of @dev that have not been added yet 2202f9aa4606SSaravana Kannan * (because @dev hasn't probed) might already have their suppliers added to 2203f9aa4606SSaravana Kannan * driver core. So, this function creates SYNC_STATE_ONLY device links between 2204f9aa4606SSaravana Kannan * @dev (consumer) and these suppliers to make sure they don't execute their 2205f9aa4606SSaravana Kannan * sync_state() callbacks before these child devices have a chance to create 2206f9aa4606SSaravana Kannan * their device links. The fwnode links that correspond to the child devices 2207f9aa4606SSaravana Kannan * aren't delete because they are needed later to create the device links 2208f9aa4606SSaravana Kannan * between the real consumer and supplier devices. 2209f9aa4606SSaravana Kannan */ 2210f9aa4606SSaravana Kannan static void __fw_devlink_link_to_suppliers(struct device *dev, 2211f9aa4606SSaravana Kannan struct fwnode_handle *fwnode) 2212f9aa4606SSaravana Kannan { 2213f9aa4606SSaravana Kannan bool own_link = (dev->fwnode == fwnode); 2214f9aa4606SSaravana Kannan struct fwnode_link *link, *tmp; 2215f9aa4606SSaravana Kannan struct fwnode_handle *child = NULL; 2216f9aa4606SSaravana Kannan 2217f9aa4606SSaravana Kannan list_for_each_entry_safe(link, tmp, &fwnode->suppliers, c_hook) { 2218f9aa4606SSaravana Kannan int ret; 2219f9aa4606SSaravana Kannan struct fwnode_handle *sup = link->supplier; 2220f9aa4606SSaravana Kannan 2221cd115c04SSaravana Kannan ret = fw_devlink_create_devlink(dev, sup, link); 2222f9aa4606SSaravana Kannan if (!own_link || ret == -EAGAIN) 2223f9aa4606SSaravana Kannan continue; 2224f9aa4606SSaravana Kannan 222576f13081SSaravana Kannan __fwnode_link_del(link); 2226f9aa4606SSaravana Kannan } 2227f9aa4606SSaravana Kannan 2228f9aa4606SSaravana Kannan /* 2229f9aa4606SSaravana Kannan * Make "proxy" SYNC_STATE_ONLY device links to represent the needs of 2230f9aa4606SSaravana Kannan * all the descendants. This proxy link step is needed to handle the 2231f9aa4606SSaravana Kannan * case where the supplier is added before the consumer's parent device 2232f9aa4606SSaravana Kannan * (@dev). 2233f9aa4606SSaravana Kannan */ 2234f9aa4606SSaravana Kannan while ((child = fwnode_get_next_available_child_node(fwnode, child))) 2235f9aa4606SSaravana Kannan __fw_devlink_link_to_suppliers(dev, child); 2236f9aa4606SSaravana Kannan } 2237f9aa4606SSaravana Kannan 22381da177e4SLinus Torvalds static void fw_devlink_link_device(struct device *dev) 22391da177e4SLinus Torvalds { 2240f9aa4606SSaravana Kannan struct fwnode_handle *fwnode = dev->fwnode; 22411da177e4SLinus Torvalds 2242f9aa4606SSaravana Kannan if (!fw_devlink_flags) 2243f9aa4606SSaravana Kannan return; 22441da177e4SLinus Torvalds 2245f9aa4606SSaravana Kannan fw_devlink_parse_fwtree(fwnode); 2246f9aa4606SSaravana Kannan 2247f9aa4606SSaravana Kannan mutex_lock(&fwnode_link_lock); 2248f9aa4606SSaravana Kannan __fw_devlink_link_to_consumers(dev); 2249f9aa4606SSaravana Kannan __fw_devlink_link_to_suppliers(dev, fwnode); 2250f9aa4606SSaravana Kannan mutex_unlock(&fwnode_link_lock); 22511da177e4SLinus Torvalds } 22521da177e4SLinus Torvalds 22531da177e4SLinus Torvalds /* Device links support end. */ 22541da177e4SLinus Torvalds 22551da177e4SLinus Torvalds int (*platform_notify)(struct device *dev) = NULL; 22561da177e4SLinus Torvalds int (*platform_notify_remove)(struct device *dev) = NULL; 22571da177e4SLinus Torvalds static struct kobject *dev_kobj; 22581da177e4SLinus Torvalds struct kobject *sysfs_dev_char_kobj; 22591da177e4SLinus Torvalds struct kobject *sysfs_dev_block_kobj; 22601da177e4SLinus Torvalds 22611da177e4SLinus Torvalds static DEFINE_MUTEX(device_hotplug_lock); 22621da177e4SLinus Torvalds 22631da177e4SLinus Torvalds void lock_device_hotplug(void) 22641da177e4SLinus Torvalds { 22651da177e4SLinus Torvalds mutex_lock(&device_hotplug_lock); 22661da177e4SLinus Torvalds } 22671da177e4SLinus Torvalds 22681da177e4SLinus Torvalds void unlock_device_hotplug(void) 22691da177e4SLinus Torvalds { 22701da177e4SLinus Torvalds mutex_unlock(&device_hotplug_lock); 22711da177e4SLinus Torvalds } 22721da177e4SLinus Torvalds 22731da177e4SLinus Torvalds int lock_device_hotplug_sysfs(void) 22741da177e4SLinus Torvalds { 22751da177e4SLinus Torvalds if (mutex_trylock(&device_hotplug_lock)) 22761da177e4SLinus Torvalds return 0; 22771da177e4SLinus Torvalds 22781da177e4SLinus Torvalds /* Avoid busy looping (5 ms of sleep should do). */ 22791da177e4SLinus Torvalds msleep(5); 22801da177e4SLinus Torvalds return restart_syscall(); 22811da177e4SLinus Torvalds } 22821da177e4SLinus Torvalds 22831da177e4SLinus Torvalds #ifdef CONFIG_BLOCK 22841da177e4SLinus Torvalds static inline int device_is_not_partition(struct device *dev) 22851da177e4SLinus Torvalds { 22861da177e4SLinus Torvalds return !(dev->type == &part_type); 22871da177e4SLinus Torvalds } 22881da177e4SLinus Torvalds #else 22891da177e4SLinus Torvalds static inline int device_is_not_partition(struct device *dev) 22901da177e4SLinus Torvalds { 22911da177e4SLinus Torvalds return 1; 22921da177e4SLinus Torvalds } 22931da177e4SLinus Torvalds #endif 22941da177e4SLinus Torvalds 2295b2ebd9ddSRafael J. Wysocki static void device_platform_notify(struct device *dev) 229607de0e86SHeikki Krogerus { 2297d0b8e398SRafael J. Wysocki acpi_device_notify(dev); 22987847a145SHeikki Krogerus 2299b2ebd9ddSRafael J. Wysocki software_node_notify(dev); 23007847a145SHeikki Krogerus 2301b2ebd9ddSRafael J. Wysocki if (platform_notify) 230207de0e86SHeikki Krogerus platform_notify(dev); 2303b2ebd9ddSRafael J. Wysocki } 2304b2ebd9ddSRafael J. Wysocki 2305b2ebd9ddSRafael J. Wysocki static void device_platform_notify_remove(struct device *dev) 2306b2ebd9ddSRafael J. Wysocki { 2307d0b8e398SRafael J. Wysocki acpi_device_notify_remove(dev); 230807de0e86SHeikki Krogerus 2309384f5a85SRafael J. Wysocki software_node_notify_remove(dev); 23104e886c29SGreg Kroah-Hartman 2311b2ebd9ddSRafael J. Wysocki if (platform_notify_remove) 23124e886c29SGreg Kroah-Hartman platform_notify_remove(dev); 23134e886c29SGreg Kroah-Hartman } 23141da177e4SLinus Torvalds 23153e95637aSAlan Stern /** 23163e95637aSAlan Stern * dev_driver_string - Return a device's driver name, if at all possible 23173e95637aSAlan Stern * @dev: struct device to get the name of 23183e95637aSAlan Stern * 23193e95637aSAlan Stern * Will return the device's driver's name if it is bound to a device. If 23209169c012Syan * the device is not bound to a driver, it will return the name of the bus 23213e95637aSAlan Stern * it is attached to. If it is not attached to a bus either, an empty 23223e95637aSAlan Stern * string will be returned. 23233e95637aSAlan Stern */ 2324bf9ca69fSJean Delvare const char *dev_driver_string(const struct device *dev) 23253e95637aSAlan Stern { 23263589972eSAlan Stern struct device_driver *drv; 23273589972eSAlan Stern 23283589972eSAlan Stern /* dev->driver can change to NULL underneath us because of unbinding, 23293589972eSAlan Stern * so be careful about accessing it. dev->bus and dev->class should 23303589972eSAlan Stern * never change once they are set, so they don't need special care. 23313589972eSAlan Stern */ 23326aa7de05SMark Rutland drv = READ_ONCE(dev->driver); 2333e020ff61SSaravana Kannan return drv ? drv->name : dev_bus_name(dev); 23343e95637aSAlan Stern } 2335310a922dSMatthew Wilcox EXPORT_SYMBOL(dev_driver_string); 23363e95637aSAlan Stern 23371da177e4SLinus Torvalds #define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr) 23381da177e4SLinus Torvalds 23394a3ad20cSGreg Kroah-Hartman static ssize_t dev_attr_show(struct kobject *kobj, struct attribute *attr, 23404a3ad20cSGreg Kroah-Hartman char *buf) 23411da177e4SLinus Torvalds { 23421da177e4SLinus Torvalds struct device_attribute *dev_attr = to_dev_attr(attr); 2343b0d1f807SLars-Peter Clausen struct device *dev = kobj_to_dev(kobj); 23444a0c20bfSDmitry Torokhov ssize_t ret = -EIO; 23451da177e4SLinus Torvalds 23461da177e4SLinus Torvalds if (dev_attr->show) 234754b6f35cSYani Ioannou ret = dev_attr->show(dev, dev_attr, buf); 2348815d2d50SAndrew Morton if (ret >= (ssize_t)PAGE_SIZE) { 2349a52668c6SSergey Senozhatsky printk("dev_attr_show: %pS returned bad count\n", 2350a52668c6SSergey Senozhatsky dev_attr->show); 2351815d2d50SAndrew Morton } 23521da177e4SLinus Torvalds return ret; 23531da177e4SLinus Torvalds } 23541da177e4SLinus Torvalds 23554a3ad20cSGreg Kroah-Hartman static ssize_t dev_attr_store(struct kobject *kobj, struct attribute *attr, 23561da177e4SLinus Torvalds const char *buf, size_t count) 23571da177e4SLinus Torvalds { 23581da177e4SLinus Torvalds struct device_attribute *dev_attr = to_dev_attr(attr); 2359b0d1f807SLars-Peter Clausen struct device *dev = kobj_to_dev(kobj); 23604a0c20bfSDmitry Torokhov ssize_t ret = -EIO; 23611da177e4SLinus Torvalds 23621da177e4SLinus Torvalds if (dev_attr->store) 236354b6f35cSYani Ioannou ret = dev_attr->store(dev, dev_attr, buf, count); 23641da177e4SLinus Torvalds return ret; 23651da177e4SLinus Torvalds } 23661da177e4SLinus Torvalds 236752cf25d0SEmese Revfy static const struct sysfs_ops dev_sysfs_ops = { 23681da177e4SLinus Torvalds .show = dev_attr_show, 23691da177e4SLinus Torvalds .store = dev_attr_store, 23701da177e4SLinus Torvalds }; 23711da177e4SLinus Torvalds 2372ca22e56dSKay Sievers #define to_ext_attr(x) container_of(x, struct dev_ext_attribute, attr) 2373ca22e56dSKay Sievers 2374ca22e56dSKay Sievers ssize_t device_store_ulong(struct device *dev, 2375ca22e56dSKay Sievers struct device_attribute *attr, 2376ca22e56dSKay Sievers const char *buf, size_t size) 2377ca22e56dSKay Sievers { 2378ca22e56dSKay Sievers struct dev_ext_attribute *ea = to_ext_attr(attr); 2379f88184bfSKaitao cheng int ret; 2380f88184bfSKaitao cheng unsigned long new; 2381f88184bfSKaitao cheng 2382f88184bfSKaitao cheng ret = kstrtoul(buf, 0, &new); 2383f88184bfSKaitao cheng if (ret) 2384f88184bfSKaitao cheng return ret; 2385ca22e56dSKay Sievers *(unsigned long *)(ea->var) = new; 2386ca22e56dSKay Sievers /* Always return full write size even if we didn't consume all */ 2387ca22e56dSKay Sievers return size; 2388ca22e56dSKay Sievers } 2389ca22e56dSKay Sievers EXPORT_SYMBOL_GPL(device_store_ulong); 2390ca22e56dSKay Sievers 2391ca22e56dSKay Sievers ssize_t device_show_ulong(struct device *dev, 2392ca22e56dSKay Sievers struct device_attribute *attr, 2393ca22e56dSKay Sievers char *buf) 2394ca22e56dSKay Sievers { 2395ca22e56dSKay Sievers struct dev_ext_attribute *ea = to_ext_attr(attr); 2396aa838896SJoe Perches return sysfs_emit(buf, "%lx\n", *(unsigned long *)(ea->var)); 2397ca22e56dSKay Sievers } 2398ca22e56dSKay Sievers EXPORT_SYMBOL_GPL(device_show_ulong); 2399ca22e56dSKay Sievers 2400ca22e56dSKay Sievers ssize_t device_store_int(struct device *dev, 2401ca22e56dSKay Sievers struct device_attribute *attr, 2402ca22e56dSKay Sievers const char *buf, size_t size) 2403ca22e56dSKay Sievers { 2404ca22e56dSKay Sievers struct dev_ext_attribute *ea = to_ext_attr(attr); 2405f88184bfSKaitao cheng int ret; 2406f88184bfSKaitao cheng long new; 2407f88184bfSKaitao cheng 2408f88184bfSKaitao cheng ret = kstrtol(buf, 0, &new); 2409f88184bfSKaitao cheng if (ret) 2410f88184bfSKaitao cheng return ret; 2411f88184bfSKaitao cheng 2412f88184bfSKaitao cheng if (new > INT_MAX || new < INT_MIN) 2413ca22e56dSKay Sievers return -EINVAL; 2414ca22e56dSKay Sievers *(int *)(ea->var) = new; 2415ca22e56dSKay Sievers /* Always return full write size even if we didn't consume all */ 2416ca22e56dSKay Sievers return size; 2417ca22e56dSKay Sievers } 2418ca22e56dSKay Sievers EXPORT_SYMBOL_GPL(device_store_int); 2419ca22e56dSKay Sievers 2420ca22e56dSKay Sievers ssize_t device_show_int(struct device *dev, 2421ca22e56dSKay Sievers struct device_attribute *attr, 2422ca22e56dSKay Sievers char *buf) 2423ca22e56dSKay Sievers { 2424ca22e56dSKay Sievers struct dev_ext_attribute *ea = to_ext_attr(attr); 2425ca22e56dSKay Sievers 2426aa838896SJoe Perches return sysfs_emit(buf, "%d\n", *(int *)(ea->var)); 2427ca22e56dSKay Sievers } 2428ca22e56dSKay Sievers EXPORT_SYMBOL_GPL(device_show_int); 24291da177e4SLinus Torvalds 243091872392SBorislav Petkov ssize_t device_store_bool(struct device *dev, struct device_attribute *attr, 243191872392SBorislav Petkov const char *buf, size_t size) 243291872392SBorislav Petkov { 243391872392SBorislav Petkov struct dev_ext_attribute *ea = to_ext_attr(attr); 243491872392SBorislav Petkov 243573060022SChristophe JAILLET if (kstrtobool(buf, ea->var) < 0) 243691872392SBorislav Petkov return -EINVAL; 243791872392SBorislav Petkov 243891872392SBorislav Petkov return size; 243991872392SBorislav Petkov } 244091872392SBorislav Petkov EXPORT_SYMBOL_GPL(device_store_bool); 244191872392SBorislav Petkov 244291872392SBorislav Petkov ssize_t device_show_bool(struct device *dev, struct device_attribute *attr, 244391872392SBorislav Petkov char *buf) 244491872392SBorislav Petkov { 244591872392SBorislav Petkov struct dev_ext_attribute *ea = to_ext_attr(attr); 244691872392SBorislav Petkov 2447aa838896SJoe Perches return sysfs_emit(buf, "%d\n", *(bool *)(ea->var)); 244891872392SBorislav Petkov } 244991872392SBorislav Petkov EXPORT_SYMBOL_GPL(device_show_bool); 245091872392SBorislav Petkov 24511da177e4SLinus Torvalds /** 24521da177e4SLinus Torvalds * device_release - free device structure. 24531da177e4SLinus Torvalds * @kobj: device's kobject. 24541da177e4SLinus Torvalds * 24551da177e4SLinus Torvalds * This is called once the reference count for the object 24561da177e4SLinus Torvalds * reaches 0. We forward the call to the device's release 24571da177e4SLinus Torvalds * method, which should handle actually freeing the structure. 24581da177e4SLinus Torvalds */ 24591da177e4SLinus Torvalds static void device_release(struct kobject *kobj) 24601da177e4SLinus Torvalds { 2461b0d1f807SLars-Peter Clausen struct device *dev = kobj_to_dev(kobj); 2462fb069a5dSGreg Kroah-Hartman struct device_private *p = dev->p; 24631da177e4SLinus Torvalds 2464a525a3ddSMing Lei /* 2465a525a3ddSMing Lei * Some platform devices are driven without driver attached 2466a525a3ddSMing Lei * and managed resources may have been acquired. Make sure 2467a525a3ddSMing Lei * all resources are released. 2468a525a3ddSMing Lei * 2469a525a3ddSMing Lei * Drivers still can add resources into device after device 2470a525a3ddSMing Lei * is deleted but alive, so release devres here to avoid 2471a525a3ddSMing Lei * possible memory leak. 2472a525a3ddSMing Lei */ 2473a525a3ddSMing Lei devres_release_all(dev); 2474a525a3ddSMing Lei 2475e0d07278SJim Quinlan kfree(dev->dma_range_map); 2476e0d07278SJim Quinlan 24771da177e4SLinus Torvalds if (dev->release) 24781da177e4SLinus Torvalds dev->release(dev); 2479f9f852dfSKay Sievers else if (dev->type && dev->type->release) 2480f9f852dfSKay Sievers dev->type->release(dev); 24812620efefSGreg Kroah-Hartman else if (dev->class && dev->class->dev_release) 24822620efefSGreg Kroah-Hartman dev->class->dev_release(dev); 2483f810a5cfSArjan van de Ven else 24840c1bc6b8SMauro Carvalho Chehab WARN(1, KERN_ERR "Device '%s' does not have a release() function, it is broken and must be fixed. See Documentation/core-api/kobject.rst.\n", 24851e0b2cf9SKay Sievers dev_name(dev)); 2486fb069a5dSGreg Kroah-Hartman kfree(p); 24871da177e4SLinus Torvalds } 24881da177e4SLinus Torvalds 248902a476d9SGreg Kroah-Hartman static const void *device_namespace(const struct kobject *kobj) 2490bc451f20SEric W. Biederman { 2491fa627348SGreg Kroah-Hartman const struct device *dev = kobj_to_dev(kobj); 2492bc451f20SEric W. Biederman const void *ns = NULL; 2493bc451f20SEric W. Biederman 2494bc451f20SEric W. Biederman if (dev->class && dev->class->ns_type) 2495bc451f20SEric W. Biederman ns = dev->class->namespace(dev); 2496bc451f20SEric W. Biederman 2497bc451f20SEric W. Biederman return ns; 2498bc451f20SEric W. Biederman } 2499bc451f20SEric W. Biederman 250002a476d9SGreg Kroah-Hartman static void device_get_ownership(const struct kobject *kobj, kuid_t *uid, kgid_t *gid) 25019944e894SDmitry Torokhov { 2502fa627348SGreg Kroah-Hartman const struct device *dev = kobj_to_dev(kobj); 25039944e894SDmitry Torokhov 25049944e894SDmitry Torokhov if (dev->class && dev->class->get_ownership) 25059944e894SDmitry Torokhov dev->class->get_ownership(dev, uid, gid); 25069944e894SDmitry Torokhov } 25079944e894SDmitry Torokhov 2508c83d9ab4SThomas Weißschuh static const struct kobj_type device_ktype = { 25091da177e4SLinus Torvalds .release = device_release, 25101da177e4SLinus Torvalds .sysfs_ops = &dev_sysfs_ops, 2511bc451f20SEric W. Biederman .namespace = device_namespace, 25129944e894SDmitry Torokhov .get_ownership = device_get_ownership, 25131da177e4SLinus Torvalds }; 25141da177e4SLinus Torvalds 25151da177e4SLinus Torvalds 2516c45a88bbSGreg Kroah-Hartman static int dev_uevent_filter(const struct kobject *kobj) 25171da177e4SLinus Torvalds { 2518ee6d3dd4SWedson Almeida Filho const struct kobj_type *ktype = get_ktype(kobj); 25191da177e4SLinus Torvalds 25208f4afc41SGreg Kroah-Hartman if (ktype == &device_ktype) { 2521c45a88bbSGreg Kroah-Hartman const struct device *dev = kobj_to_dev(kobj); 25221da177e4SLinus Torvalds if (dev->bus) 25231da177e4SLinus Torvalds return 1; 252423681e47SGreg Kroah-Hartman if (dev->class) 252523681e47SGreg Kroah-Hartman return 1; 25261da177e4SLinus Torvalds } 25271da177e4SLinus Torvalds return 0; 25281da177e4SLinus Torvalds } 25291da177e4SLinus Torvalds 2530a53d1accSGreg Kroah-Hartman static const char *dev_uevent_name(const struct kobject *kobj) 25311da177e4SLinus Torvalds { 2532a53d1accSGreg Kroah-Hartman const struct device *dev = kobj_to_dev(kobj); 25331da177e4SLinus Torvalds 253423681e47SGreg Kroah-Hartman if (dev->bus) 25351da177e4SLinus Torvalds return dev->bus->name; 253623681e47SGreg Kroah-Hartman if (dev->class) 253723681e47SGreg Kroah-Hartman return dev->class->name; 253823681e47SGreg Kroah-Hartman return NULL; 25391da177e4SLinus Torvalds } 25401da177e4SLinus Torvalds 254156d5f362SGreg Kroah-Hartman static int dev_uevent(const struct kobject *kobj, struct kobj_uevent_env *env) 25421da177e4SLinus Torvalds { 254356d5f362SGreg Kroah-Hartman const struct device *dev = kobj_to_dev(kobj); 25441da177e4SLinus Torvalds int retval = 0; 25451da177e4SLinus Torvalds 25466fcf53acSKay Sievers /* add device node properties if present */ 254723681e47SGreg Kroah-Hartman if (MAJOR(dev->devt)) { 25486fcf53acSKay Sievers const char *tmp; 25496fcf53acSKay Sievers const char *name; 25502c9ede55SAl Viro umode_t mode = 0; 25514e4098a3SGreg Kroah-Hartman kuid_t uid = GLOBAL_ROOT_UID; 25524e4098a3SGreg Kroah-Hartman kgid_t gid = GLOBAL_ROOT_GID; 25536fcf53acSKay Sievers 25547eff2e7aSKay Sievers add_uevent_var(env, "MAJOR=%u", MAJOR(dev->devt)); 25557eff2e7aSKay Sievers add_uevent_var(env, "MINOR=%u", MINOR(dev->devt)); 25563c2670e6SKay Sievers name = device_get_devnode(dev, &mode, &uid, &gid, &tmp); 25576fcf53acSKay Sievers if (name) { 25586fcf53acSKay Sievers add_uevent_var(env, "DEVNAME=%s", name); 2559e454cea2SKay Sievers if (mode) 2560e454cea2SKay Sievers add_uevent_var(env, "DEVMODE=%#o", mode & 0777); 25614e4098a3SGreg Kroah-Hartman if (!uid_eq(uid, GLOBAL_ROOT_UID)) 25624e4098a3SGreg Kroah-Hartman add_uevent_var(env, "DEVUID=%u", from_kuid(&init_user_ns, uid)); 25634e4098a3SGreg Kroah-Hartman if (!gid_eq(gid, GLOBAL_ROOT_GID)) 25644e4098a3SGreg Kroah-Hartman add_uevent_var(env, "DEVGID=%u", from_kgid(&init_user_ns, gid)); 25653c2670e6SKay Sievers kfree(tmp); 25666fcf53acSKay Sievers } 256723681e47SGreg Kroah-Hartman } 256823681e47SGreg Kroah-Hartman 2569414264f9SKay Sievers if (dev->type && dev->type->name) 25707eff2e7aSKay Sievers add_uevent_var(env, "DEVTYPE=%s", dev->type->name); 2571414264f9SKay Sievers 2572239378f1SKay Sievers if (dev->driver) 25737eff2e7aSKay Sievers add_uevent_var(env, "DRIVER=%s", dev->driver->name); 2574239378f1SKay Sievers 257507d57a32SGrant Likely /* Add common DT information about the device */ 257607d57a32SGrant Likely of_device_uevent(dev, env); 257707d57a32SGrant Likely 25781da177e4SLinus Torvalds /* have the bus specific function add its stuff */ 25797eff2e7aSKay Sievers if (dev->bus && dev->bus->uevent) { 25807eff2e7aSKay Sievers retval = dev->bus->uevent(dev, env); 2581f9f852dfSKay Sievers if (retval) 25827dc72b28SGreg Kroah-Hartman pr_debug("device: '%s': %s: bus uevent() returned %d\n", 25831e0b2cf9SKay Sievers dev_name(dev), __func__, retval); 25841da177e4SLinus Torvalds } 25851da177e4SLinus Torvalds 25862620efefSGreg Kroah-Hartman /* have the class specific function add its stuff */ 25877eff2e7aSKay Sievers if (dev->class && dev->class->dev_uevent) { 25887eff2e7aSKay Sievers retval = dev->class->dev_uevent(dev, env); 2589f9f852dfSKay Sievers if (retval) 25907dc72b28SGreg Kroah-Hartman pr_debug("device: '%s': %s: class uevent() " 25911e0b2cf9SKay Sievers "returned %d\n", dev_name(dev), 25922b3a302aSHarvey Harrison __func__, retval); 25932620efefSGreg Kroah-Hartman } 2594f9f852dfSKay Sievers 2595eef35c2dSStefan Weil /* have the device type specific function add its stuff */ 25967eff2e7aSKay Sievers if (dev->type && dev->type->uevent) { 25977eff2e7aSKay Sievers retval = dev->type->uevent(dev, env); 2598f9f852dfSKay Sievers if (retval) 25997dc72b28SGreg Kroah-Hartman pr_debug("device: '%s': %s: dev_type uevent() " 26001e0b2cf9SKay Sievers "returned %d\n", dev_name(dev), 26012b3a302aSHarvey Harrison __func__, retval); 26022620efefSGreg Kroah-Hartman } 26032620efefSGreg Kroah-Hartman 26041da177e4SLinus Torvalds return retval; 26051da177e4SLinus Torvalds } 26061da177e4SLinus Torvalds 26079cd43611SEmese Revfy static const struct kset_uevent_ops device_uevent_ops = { 2608312c004dSKay Sievers .filter = dev_uevent_filter, 2609312c004dSKay Sievers .name = dev_uevent_name, 2610312c004dSKay Sievers .uevent = dev_uevent, 26111da177e4SLinus Torvalds }; 26121da177e4SLinus Torvalds 2613c5e064a6SGreg Kroah-Hartman static ssize_t uevent_show(struct device *dev, struct device_attribute *attr, 261416574dccSKay Sievers char *buf) 261516574dccSKay Sievers { 261616574dccSKay Sievers struct kobject *top_kobj; 261716574dccSKay Sievers struct kset *kset; 26187eff2e7aSKay Sievers struct kobj_uevent_env *env = NULL; 261916574dccSKay Sievers int i; 2620948b3edbSJoe Perches int len = 0; 262116574dccSKay Sievers int retval; 262216574dccSKay Sievers 262316574dccSKay Sievers /* search the kset, the device belongs to */ 262416574dccSKay Sievers top_kobj = &dev->kobj; 26255c5daf65SKay Sievers while (!top_kobj->kset && top_kobj->parent) 262616574dccSKay Sievers top_kobj = top_kobj->parent; 262716574dccSKay Sievers if (!top_kobj->kset) 262816574dccSKay Sievers goto out; 26295c5daf65SKay Sievers 263016574dccSKay Sievers kset = top_kobj->kset; 263116574dccSKay Sievers if (!kset->uevent_ops || !kset->uevent_ops->uevent) 263216574dccSKay Sievers goto out; 263316574dccSKay Sievers 263416574dccSKay Sievers /* respect filter */ 263516574dccSKay Sievers if (kset->uevent_ops && kset->uevent_ops->filter) 2636cf6299b6SGreg Kroah-Hartman if (!kset->uevent_ops->filter(&dev->kobj)) 263716574dccSKay Sievers goto out; 263816574dccSKay Sievers 26397eff2e7aSKay Sievers env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL); 26407eff2e7aSKay Sievers if (!env) 2641c7308c81SGreg Kroah-Hartman return -ENOMEM; 2642c7308c81SGreg Kroah-Hartman 264316574dccSKay Sievers /* let the kset specific function add its keys */ 2644cf6299b6SGreg Kroah-Hartman retval = kset->uevent_ops->uevent(&dev->kobj, env); 264516574dccSKay Sievers if (retval) 264616574dccSKay Sievers goto out; 264716574dccSKay Sievers 264816574dccSKay Sievers /* copy keys to file */ 26497eff2e7aSKay Sievers for (i = 0; i < env->envp_idx; i++) 2650948b3edbSJoe Perches len += sysfs_emit_at(buf, len, "%s\n", env->envp[i]); 265116574dccSKay Sievers out: 26527eff2e7aSKay Sievers kfree(env); 2653948b3edbSJoe Perches return len; 265416574dccSKay Sievers } 265516574dccSKay Sievers 2656c5e064a6SGreg Kroah-Hartman static ssize_t uevent_store(struct device *dev, struct device_attribute *attr, 2657a7fd6706SKay Sievers const char *buf, size_t count) 2658a7fd6706SKay Sievers { 2659df44b479SPeter Rajnoha int rc; 2660df44b479SPeter Rajnoha 2661df44b479SPeter Rajnoha rc = kobject_synth_uevent(&dev->kobj, buf, count); 2662df44b479SPeter Rajnoha 2663df44b479SPeter Rajnoha if (rc) { 26646bb7ea3aSBrian Norris dev_err(dev, "uevent: failed to send synthetic uevent: %d\n", rc); 2665df44b479SPeter Rajnoha return rc; 2666df44b479SPeter Rajnoha } 266760a96a59SKay Sievers 2668a7fd6706SKay Sievers return count; 2669a7fd6706SKay Sievers } 2670c5e064a6SGreg Kroah-Hartman static DEVICE_ATTR_RW(uevent); 2671a7fd6706SKay Sievers 2672c5e064a6SGreg Kroah-Hartman static ssize_t online_show(struct device *dev, struct device_attribute *attr, 26734f3549d7SRafael J. Wysocki char *buf) 26744f3549d7SRafael J. Wysocki { 26754f3549d7SRafael J. Wysocki bool val; 26764f3549d7SRafael J. Wysocki 26775e33bc41SRafael J. Wysocki device_lock(dev); 26784f3549d7SRafael J. Wysocki val = !dev->offline; 26795e33bc41SRafael J. Wysocki device_unlock(dev); 2680aa838896SJoe Perches return sysfs_emit(buf, "%u\n", val); 26814f3549d7SRafael J. Wysocki } 26824f3549d7SRafael J. Wysocki 2683c5e064a6SGreg Kroah-Hartman static ssize_t online_store(struct device *dev, struct device_attribute *attr, 26844f3549d7SRafael J. Wysocki const char *buf, size_t count) 26854f3549d7SRafael J. Wysocki { 26864f3549d7SRafael J. Wysocki bool val; 26874f3549d7SRafael J. Wysocki int ret; 26884f3549d7SRafael J. Wysocki 268973060022SChristophe JAILLET ret = kstrtobool(buf, &val); 26904f3549d7SRafael J. Wysocki if (ret < 0) 26914f3549d7SRafael J. Wysocki return ret; 26924f3549d7SRafael J. Wysocki 26935e33bc41SRafael J. Wysocki ret = lock_device_hotplug_sysfs(); 26945e33bc41SRafael J. Wysocki if (ret) 26955e33bc41SRafael J. Wysocki return ret; 26965e33bc41SRafael J. Wysocki 26974f3549d7SRafael J. Wysocki ret = val ? device_online(dev) : device_offline(dev); 26984f3549d7SRafael J. Wysocki unlock_device_hotplug(); 26994f3549d7SRafael J. Wysocki return ret < 0 ? ret : count; 27004f3549d7SRafael J. Wysocki } 2701c5e064a6SGreg Kroah-Hartman static DEVICE_ATTR_RW(online); 27024f3549d7SRafael J. Wysocki 270370f400d4SRajat Jain static ssize_t removable_show(struct device *dev, struct device_attribute *attr, 270470f400d4SRajat Jain char *buf) 270570f400d4SRajat Jain { 270670f400d4SRajat Jain const char *loc; 270770f400d4SRajat Jain 270870f400d4SRajat Jain switch (dev->removable) { 270970f400d4SRajat Jain case DEVICE_REMOVABLE: 271070f400d4SRajat Jain loc = "removable"; 271170f400d4SRajat Jain break; 271270f400d4SRajat Jain case DEVICE_FIXED: 271370f400d4SRajat Jain loc = "fixed"; 271470f400d4SRajat Jain break; 271570f400d4SRajat Jain default: 271670f400d4SRajat Jain loc = "unknown"; 271770f400d4SRajat Jain } 271870f400d4SRajat Jain return sysfs_emit(buf, "%s\n", loc); 271970f400d4SRajat Jain } 272070f400d4SRajat Jain static DEVICE_ATTR_RO(removable); 272170f400d4SRajat Jain 2722fa6fdb33SGreg Kroah-Hartman int device_add_groups(struct device *dev, const struct attribute_group **groups) 2723621a1672SDmitry Torokhov { 27243e9b2baeSGreg Kroah-Hartman return sysfs_create_groups(&dev->kobj, groups); 2725621a1672SDmitry Torokhov } 2726a7670d42SDmitry Torokhov EXPORT_SYMBOL_GPL(device_add_groups); 2727621a1672SDmitry Torokhov 2728fa6fdb33SGreg Kroah-Hartman void device_remove_groups(struct device *dev, 2729a4dbd674SDavid Brownell const struct attribute_group **groups) 2730621a1672SDmitry Torokhov { 27313e9b2baeSGreg Kroah-Hartman sysfs_remove_groups(&dev->kobj, groups); 2732621a1672SDmitry Torokhov } 2733a7670d42SDmitry Torokhov EXPORT_SYMBOL_GPL(device_remove_groups); 2734de0ff00dSGreg Kroah-Hartman 273557b8ff07SDmitry Torokhov union device_attr_group_devres { 273657b8ff07SDmitry Torokhov const struct attribute_group *group; 273757b8ff07SDmitry Torokhov const struct attribute_group **groups; 273857b8ff07SDmitry Torokhov }; 273957b8ff07SDmitry Torokhov 274057b8ff07SDmitry Torokhov static void devm_attr_group_remove(struct device *dev, void *res) 274157b8ff07SDmitry Torokhov { 274257b8ff07SDmitry Torokhov union device_attr_group_devres *devres = res; 274357b8ff07SDmitry Torokhov const struct attribute_group *group = devres->group; 274457b8ff07SDmitry Torokhov 274557b8ff07SDmitry Torokhov dev_dbg(dev, "%s: removing group %p\n", __func__, group); 274657b8ff07SDmitry Torokhov sysfs_remove_group(&dev->kobj, group); 274757b8ff07SDmitry Torokhov } 274857b8ff07SDmitry Torokhov 274957b8ff07SDmitry Torokhov static void devm_attr_groups_remove(struct device *dev, void *res) 275057b8ff07SDmitry Torokhov { 275157b8ff07SDmitry Torokhov union device_attr_group_devres *devres = res; 275257b8ff07SDmitry Torokhov const struct attribute_group **groups = devres->groups; 275357b8ff07SDmitry Torokhov 275457b8ff07SDmitry Torokhov dev_dbg(dev, "%s: removing groups %p\n", __func__, groups); 275557b8ff07SDmitry Torokhov sysfs_remove_groups(&dev->kobj, groups); 275657b8ff07SDmitry Torokhov } 275757b8ff07SDmitry Torokhov 275857b8ff07SDmitry Torokhov /** 275957b8ff07SDmitry Torokhov * devm_device_add_group - given a device, create a managed attribute group 276057b8ff07SDmitry Torokhov * @dev: The device to create the group for 276157b8ff07SDmitry Torokhov * @grp: The attribute group to create 276257b8ff07SDmitry Torokhov * 276357b8ff07SDmitry Torokhov * This function creates a group for the first time. It will explicitly 276457b8ff07SDmitry Torokhov * warn and error if any of the attribute files being created already exist. 276557b8ff07SDmitry Torokhov * 276657b8ff07SDmitry Torokhov * Returns 0 on success or error code on failure. 276757b8ff07SDmitry Torokhov */ 276857b8ff07SDmitry Torokhov int devm_device_add_group(struct device *dev, const struct attribute_group *grp) 276957b8ff07SDmitry Torokhov { 277057b8ff07SDmitry Torokhov union device_attr_group_devres *devres; 277157b8ff07SDmitry Torokhov int error; 277257b8ff07SDmitry Torokhov 277357b8ff07SDmitry Torokhov devres = devres_alloc(devm_attr_group_remove, 277457b8ff07SDmitry Torokhov sizeof(*devres), GFP_KERNEL); 277557b8ff07SDmitry Torokhov if (!devres) 277657b8ff07SDmitry Torokhov return -ENOMEM; 277757b8ff07SDmitry Torokhov 277857b8ff07SDmitry Torokhov error = sysfs_create_group(&dev->kobj, grp); 277957b8ff07SDmitry Torokhov if (error) { 278057b8ff07SDmitry Torokhov devres_free(devres); 278157b8ff07SDmitry Torokhov return error; 278257b8ff07SDmitry Torokhov } 278357b8ff07SDmitry Torokhov 278457b8ff07SDmitry Torokhov devres->group = grp; 278557b8ff07SDmitry Torokhov devres_add(dev, devres); 278657b8ff07SDmitry Torokhov return 0; 278757b8ff07SDmitry Torokhov } 278857b8ff07SDmitry Torokhov EXPORT_SYMBOL_GPL(devm_device_add_group); 278957b8ff07SDmitry Torokhov 279057b8ff07SDmitry Torokhov /** 279157b8ff07SDmitry Torokhov * devm_device_add_groups - create a bunch of managed attribute groups 279257b8ff07SDmitry Torokhov * @dev: The device to create the group for 279357b8ff07SDmitry Torokhov * @groups: The attribute groups to create, NULL terminated 279457b8ff07SDmitry Torokhov * 279557b8ff07SDmitry Torokhov * This function creates a bunch of managed attribute groups. If an error 279657b8ff07SDmitry Torokhov * occurs when creating a group, all previously created groups will be 279757b8ff07SDmitry Torokhov * removed, unwinding everything back to the original state when this 279857b8ff07SDmitry Torokhov * function was called. It will explicitly warn and error if any of the 279957b8ff07SDmitry Torokhov * attribute files being created already exist. 280057b8ff07SDmitry Torokhov * 280157b8ff07SDmitry Torokhov * Returns 0 on success or error code from sysfs_create_group on failure. 280257b8ff07SDmitry Torokhov */ 280357b8ff07SDmitry Torokhov int devm_device_add_groups(struct device *dev, 280457b8ff07SDmitry Torokhov const struct attribute_group **groups) 280557b8ff07SDmitry Torokhov { 280657b8ff07SDmitry Torokhov union device_attr_group_devres *devres; 280757b8ff07SDmitry Torokhov int error; 280857b8ff07SDmitry Torokhov 280957b8ff07SDmitry Torokhov devres = devres_alloc(devm_attr_groups_remove, 281057b8ff07SDmitry Torokhov sizeof(*devres), GFP_KERNEL); 281157b8ff07SDmitry Torokhov if (!devres) 281257b8ff07SDmitry Torokhov return -ENOMEM; 281357b8ff07SDmitry Torokhov 281457b8ff07SDmitry Torokhov error = sysfs_create_groups(&dev->kobj, groups); 281557b8ff07SDmitry Torokhov if (error) { 281657b8ff07SDmitry Torokhov devres_free(devres); 281757b8ff07SDmitry Torokhov return error; 281857b8ff07SDmitry Torokhov } 281957b8ff07SDmitry Torokhov 282057b8ff07SDmitry Torokhov devres->groups = groups; 282157b8ff07SDmitry Torokhov devres_add(dev, devres); 282257b8ff07SDmitry Torokhov return 0; 282357b8ff07SDmitry Torokhov } 282457b8ff07SDmitry Torokhov EXPORT_SYMBOL_GPL(devm_device_add_groups); 282557b8ff07SDmitry Torokhov 28262620efefSGreg Kroah-Hartman static int device_add_attrs(struct device *dev) 28272620efefSGreg Kroah-Hartman { 28289fa120fbSGreg Kroah-Hartman const struct class *class = dev->class; 2829aed65af1SStephen Hemminger const struct device_type *type = dev->type; 2830621a1672SDmitry Torokhov int error; 28312620efefSGreg Kroah-Hartman 2832621a1672SDmitry Torokhov if (class) { 2833d05a6f96SGreg Kroah-Hartman error = device_add_groups(dev, class->dev_groups); 28342620efefSGreg Kroah-Hartman if (error) 2835621a1672SDmitry Torokhov return error; 2836f9f852dfSKay Sievers } 2837f9f852dfSKay Sievers 2838621a1672SDmitry Torokhov if (type) { 2839621a1672SDmitry Torokhov error = device_add_groups(dev, type->groups); 2840f9f852dfSKay Sievers if (error) 2841a6b01dedSGreg Kroah-Hartman goto err_remove_class_groups; 2842f9f852dfSKay Sievers } 2843621a1672SDmitry Torokhov 2844621a1672SDmitry Torokhov error = device_add_groups(dev, dev->groups); 2845f9f852dfSKay Sievers if (error) 2846621a1672SDmitry Torokhov goto err_remove_type_groups; 2847621a1672SDmitry Torokhov 28484f3549d7SRafael J. Wysocki if (device_supports_offline(dev) && !dev->offline_disabled) { 2849c5e064a6SGreg Kroah-Hartman error = device_create_file(dev, &dev_attr_online); 28504f3549d7SRafael J. Wysocki if (error) 2851ecfbf6fdSRafael J. Wysocki goto err_remove_dev_groups; 28524f3549d7SRafael J. Wysocki } 28534f3549d7SRafael J. Wysocki 285425ac86c6SSaravana Kannan if (fw_devlink_flags && !fw_devlink_is_permissive() && dev->fwnode) { 2855da6d6475SSaravana Kannan error = device_create_file(dev, &dev_attr_waiting_for_supplier); 2856da6d6475SSaravana Kannan if (error) 2857da6d6475SSaravana Kannan goto err_remove_dev_online; 2858da6d6475SSaravana Kannan } 2859da6d6475SSaravana Kannan 286070f400d4SRajat Jain if (dev_removable_is_valid(dev)) { 286170f400d4SRajat Jain error = device_create_file(dev, &dev_attr_removable); 286270f400d4SRajat Jain if (error) 286370f400d4SRajat Jain goto err_remove_dev_waiting_for_supplier; 286470f400d4SRajat Jain } 286570f400d4SRajat Jain 28666423d295SWon Chung if (dev_add_physical_location(dev)) { 28676423d295SWon Chung error = device_add_group(dev, 28686423d295SWon Chung &dev_attr_physical_location_group); 28696423d295SWon Chung if (error) 28706423d295SWon Chung goto err_remove_dev_removable; 28716423d295SWon Chung } 28726423d295SWon Chung 2873621a1672SDmitry Torokhov return 0; 2874621a1672SDmitry Torokhov 28756423d295SWon Chung err_remove_dev_removable: 28766423d295SWon Chung device_remove_file(dev, &dev_attr_removable); 287770f400d4SRajat Jain err_remove_dev_waiting_for_supplier: 287870f400d4SRajat Jain device_remove_file(dev, &dev_attr_waiting_for_supplier); 2879da6d6475SSaravana Kannan err_remove_dev_online: 2880da6d6475SSaravana Kannan device_remove_file(dev, &dev_attr_online); 2881ecfbf6fdSRafael J. Wysocki err_remove_dev_groups: 2882ecfbf6fdSRafael J. Wysocki device_remove_groups(dev, dev->groups); 2883621a1672SDmitry Torokhov err_remove_type_groups: 2884621a1672SDmitry Torokhov if (type) 2885621a1672SDmitry Torokhov device_remove_groups(dev, type->groups); 2886d05a6f96SGreg Kroah-Hartman err_remove_class_groups: 2887d05a6f96SGreg Kroah-Hartman if (class) 2888d05a6f96SGreg Kroah-Hartman device_remove_groups(dev, class->dev_groups); 2889f9f852dfSKay Sievers 28902620efefSGreg Kroah-Hartman return error; 28912620efefSGreg Kroah-Hartman } 28922620efefSGreg Kroah-Hartman 28932620efefSGreg Kroah-Hartman static void device_remove_attrs(struct device *dev) 28942620efefSGreg Kroah-Hartman { 28959fa120fbSGreg Kroah-Hartman const struct class *class = dev->class; 2896aed65af1SStephen Hemminger const struct device_type *type = dev->type; 28972620efefSGreg Kroah-Hartman 28986423d295SWon Chung if (dev->physical_location) { 28996423d295SWon Chung device_remove_group(dev, &dev_attr_physical_location_group); 29006423d295SWon Chung kfree(dev->physical_location); 29016423d295SWon Chung } 29026423d295SWon Chung 290370f400d4SRajat Jain device_remove_file(dev, &dev_attr_removable); 2904da6d6475SSaravana Kannan device_remove_file(dev, &dev_attr_waiting_for_supplier); 2905c5e064a6SGreg Kroah-Hartman device_remove_file(dev, &dev_attr_online); 2906621a1672SDmitry Torokhov device_remove_groups(dev, dev->groups); 2907f9f852dfSKay Sievers 2908621a1672SDmitry Torokhov if (type) 2909621a1672SDmitry Torokhov device_remove_groups(dev, type->groups); 2910621a1672SDmitry Torokhov 2911a6b01dedSGreg Kroah-Hartman if (class) 2912d05a6f96SGreg Kroah-Hartman device_remove_groups(dev, class->dev_groups); 2913c97415a7SStefan Achatz } 29142620efefSGreg Kroah-Hartman 2915c5e064a6SGreg Kroah-Hartman static ssize_t dev_show(struct device *dev, struct device_attribute *attr, 291623681e47SGreg Kroah-Hartman char *buf) 291723681e47SGreg Kroah-Hartman { 291823681e47SGreg Kroah-Hartman return print_dev_t(buf, dev->devt); 291923681e47SGreg Kroah-Hartman } 2920c5e064a6SGreg Kroah-Hartman static DEVICE_ATTR_RO(dev); 2921ad6a1e1cSTejun Heo 2922ca22e56dSKay Sievers /* /sys/devices/ */ 2923881c6cfdSGreg Kroah-Hartman struct kset *devices_kset; 29241da177e4SLinus Torvalds 29251da177e4SLinus Torvalds /** 292652cdbdd4SGrygorii Strashko * devices_kset_move_before - Move device in the devices_kset's list. 292752cdbdd4SGrygorii Strashko * @deva: Device to move. 292852cdbdd4SGrygorii Strashko * @devb: Device @deva should come before. 292952cdbdd4SGrygorii Strashko */ 293052cdbdd4SGrygorii Strashko static void devices_kset_move_before(struct device *deva, struct device *devb) 293152cdbdd4SGrygorii Strashko { 293252cdbdd4SGrygorii Strashko if (!devices_kset) 293352cdbdd4SGrygorii Strashko return; 293452cdbdd4SGrygorii Strashko pr_debug("devices_kset: Moving %s before %s\n", 293552cdbdd4SGrygorii Strashko dev_name(deva), dev_name(devb)); 293652cdbdd4SGrygorii Strashko spin_lock(&devices_kset->list_lock); 293752cdbdd4SGrygorii Strashko list_move_tail(&deva->kobj.entry, &devb->kobj.entry); 293852cdbdd4SGrygorii Strashko spin_unlock(&devices_kset->list_lock); 293952cdbdd4SGrygorii Strashko } 294052cdbdd4SGrygorii Strashko 294152cdbdd4SGrygorii Strashko /** 294252cdbdd4SGrygorii Strashko * devices_kset_move_after - Move device in the devices_kset's list. 294352cdbdd4SGrygorii Strashko * @deva: Device to move 294452cdbdd4SGrygorii Strashko * @devb: Device @deva should come after. 294552cdbdd4SGrygorii Strashko */ 294652cdbdd4SGrygorii Strashko static void devices_kset_move_after(struct device *deva, struct device *devb) 294752cdbdd4SGrygorii Strashko { 294852cdbdd4SGrygorii Strashko if (!devices_kset) 294952cdbdd4SGrygorii Strashko return; 295052cdbdd4SGrygorii Strashko pr_debug("devices_kset: Moving %s after %s\n", 295152cdbdd4SGrygorii Strashko dev_name(deva), dev_name(devb)); 295252cdbdd4SGrygorii Strashko spin_lock(&devices_kset->list_lock); 295352cdbdd4SGrygorii Strashko list_move(&deva->kobj.entry, &devb->kobj.entry); 295452cdbdd4SGrygorii Strashko spin_unlock(&devices_kset->list_lock); 295552cdbdd4SGrygorii Strashko } 295652cdbdd4SGrygorii Strashko 295752cdbdd4SGrygorii Strashko /** 295852cdbdd4SGrygorii Strashko * devices_kset_move_last - move the device to the end of devices_kset's list. 295952cdbdd4SGrygorii Strashko * @dev: device to move 296052cdbdd4SGrygorii Strashko */ 296152cdbdd4SGrygorii Strashko void devices_kset_move_last(struct device *dev) 296252cdbdd4SGrygorii Strashko { 296352cdbdd4SGrygorii Strashko if (!devices_kset) 296452cdbdd4SGrygorii Strashko return; 296552cdbdd4SGrygorii Strashko pr_debug("devices_kset: Moving %s to end of list\n", dev_name(dev)); 296652cdbdd4SGrygorii Strashko spin_lock(&devices_kset->list_lock); 296752cdbdd4SGrygorii Strashko list_move_tail(&dev->kobj.entry, &devices_kset->list); 296852cdbdd4SGrygorii Strashko spin_unlock(&devices_kset->list_lock); 296952cdbdd4SGrygorii Strashko } 297052cdbdd4SGrygorii Strashko 297152cdbdd4SGrygorii Strashko /** 29721da177e4SLinus Torvalds * device_create_file - create sysfs attribute file for device. 29731da177e4SLinus Torvalds * @dev: device. 29741da177e4SLinus Torvalds * @attr: device attribute descriptor. 29751da177e4SLinus Torvalds */ 297626579ab7SPhil Carmody int device_create_file(struct device *dev, 297726579ab7SPhil Carmody const struct device_attribute *attr) 29781da177e4SLinus Torvalds { 29791da177e4SLinus Torvalds int error = 0; 29808f46baaaSFelipe Balbi 29818f46baaaSFelipe Balbi if (dev) { 29828f46baaaSFelipe Balbi WARN(((attr->attr.mode & S_IWUGO) && !attr->store), 298397521978Sdyoung@redhat.com "Attribute %s: write permission without 'store'\n", 298497521978Sdyoung@redhat.com attr->attr.name); 29858f46baaaSFelipe Balbi WARN(((attr->attr.mode & S_IRUGO) && !attr->show), 298697521978Sdyoung@redhat.com "Attribute %s: read permission without 'show'\n", 298797521978Sdyoung@redhat.com attr->attr.name); 29881da177e4SLinus Torvalds error = sysfs_create_file(&dev->kobj, &attr->attr); 29898f46baaaSFelipe Balbi } 29908f46baaaSFelipe Balbi 29911da177e4SLinus Torvalds return error; 29921da177e4SLinus Torvalds } 299386df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_create_file); 29941da177e4SLinus Torvalds 29951da177e4SLinus Torvalds /** 29961da177e4SLinus Torvalds * device_remove_file - remove sysfs attribute file. 29971da177e4SLinus Torvalds * @dev: device. 29981da177e4SLinus Torvalds * @attr: device attribute descriptor. 29991da177e4SLinus Torvalds */ 300026579ab7SPhil Carmody void device_remove_file(struct device *dev, 300126579ab7SPhil Carmody const struct device_attribute *attr) 30021da177e4SLinus Torvalds { 30030c98b19fSCornelia Huck if (dev) 30041da177e4SLinus Torvalds sysfs_remove_file(&dev->kobj, &attr->attr); 30051da177e4SLinus Torvalds } 300686df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_remove_file); 30071da177e4SLinus Torvalds 30082589f188SGreg Kroah-Hartman /** 30096b0afc2aSTejun Heo * device_remove_file_self - remove sysfs attribute file from its own method. 30106b0afc2aSTejun Heo * @dev: device. 30116b0afc2aSTejun Heo * @attr: device attribute descriptor. 30126b0afc2aSTejun Heo * 30136b0afc2aSTejun Heo * See kernfs_remove_self() for details. 30146b0afc2aSTejun Heo */ 30156b0afc2aSTejun Heo bool device_remove_file_self(struct device *dev, 30166b0afc2aSTejun Heo const struct device_attribute *attr) 30176b0afc2aSTejun Heo { 30186b0afc2aSTejun Heo if (dev) 30196b0afc2aSTejun Heo return sysfs_remove_file_self(&dev->kobj, &attr->attr); 30206b0afc2aSTejun Heo else 30216b0afc2aSTejun Heo return false; 30226b0afc2aSTejun Heo } 30236b0afc2aSTejun Heo EXPORT_SYMBOL_GPL(device_remove_file_self); 30246b0afc2aSTejun Heo 30256b0afc2aSTejun Heo /** 30262589f188SGreg Kroah-Hartman * device_create_bin_file - create sysfs binary attribute file for device. 30272589f188SGreg Kroah-Hartman * @dev: device. 30282589f188SGreg Kroah-Hartman * @attr: device binary attribute descriptor. 30292589f188SGreg Kroah-Hartman */ 303066ecb92bSPhil Carmody int device_create_bin_file(struct device *dev, 303166ecb92bSPhil Carmody const struct bin_attribute *attr) 30322589f188SGreg Kroah-Hartman { 30332589f188SGreg Kroah-Hartman int error = -EINVAL; 30342589f188SGreg Kroah-Hartman if (dev) 30352589f188SGreg Kroah-Hartman error = sysfs_create_bin_file(&dev->kobj, attr); 30362589f188SGreg Kroah-Hartman return error; 30372589f188SGreg Kroah-Hartman } 30382589f188SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(device_create_bin_file); 30392589f188SGreg Kroah-Hartman 30402589f188SGreg Kroah-Hartman /** 30412589f188SGreg Kroah-Hartman * device_remove_bin_file - remove sysfs binary attribute file 30422589f188SGreg Kroah-Hartman * @dev: device. 30432589f188SGreg Kroah-Hartman * @attr: device binary attribute descriptor. 30442589f188SGreg Kroah-Hartman */ 304566ecb92bSPhil Carmody void device_remove_bin_file(struct device *dev, 304666ecb92bSPhil Carmody const struct bin_attribute *attr) 30472589f188SGreg Kroah-Hartman { 30482589f188SGreg Kroah-Hartman if (dev) 30492589f188SGreg Kroah-Hartman sysfs_remove_bin_file(&dev->kobj, attr); 30502589f188SGreg Kroah-Hartman } 30512589f188SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(device_remove_bin_file); 30522589f188SGreg Kroah-Hartman 305334bb61f9SJames Bottomley static void klist_children_get(struct klist_node *n) 305434bb61f9SJames Bottomley { 3055f791b8c8SGreg Kroah-Hartman struct device_private *p = to_device_private_parent(n); 3056f791b8c8SGreg Kroah-Hartman struct device *dev = p->device; 305734bb61f9SJames Bottomley 305834bb61f9SJames Bottomley get_device(dev); 305934bb61f9SJames Bottomley } 306034bb61f9SJames Bottomley 306134bb61f9SJames Bottomley static void klist_children_put(struct klist_node *n) 306234bb61f9SJames Bottomley { 3063f791b8c8SGreg Kroah-Hartman struct device_private *p = to_device_private_parent(n); 3064f791b8c8SGreg Kroah-Hartman struct device *dev = p->device; 306534bb61f9SJames Bottomley 306634bb61f9SJames Bottomley put_device(dev); 306734bb61f9SJames Bottomley } 306834bb61f9SJames Bottomley 30691da177e4SLinus Torvalds /** 30701da177e4SLinus Torvalds * device_initialize - init device structure. 30711da177e4SLinus Torvalds * @dev: device. 30721da177e4SLinus Torvalds * 30735739411aSCornelia Huck * This prepares the device for use by other layers by initializing 30745739411aSCornelia Huck * its fields. 30751da177e4SLinus Torvalds * It is the first half of device_register(), if called by 30765739411aSCornelia Huck * that function, though it can also be called separately, so one 30775739411aSCornelia Huck * may use @dev's fields. In particular, get_device()/put_device() 30785739411aSCornelia Huck * may be used for reference counting of @dev after calling this 30795739411aSCornelia Huck * function. 30805739411aSCornelia Huck * 3081b10d5efdSAlan Stern * All fields in @dev must be initialized by the caller to 0, except 3082b10d5efdSAlan Stern * for those explicitly set to some other value. The simplest 3083b10d5efdSAlan Stern * approach is to use kzalloc() to allocate the structure containing 3084b10d5efdSAlan Stern * @dev. 3085b10d5efdSAlan Stern * 30865739411aSCornelia Huck * NOTE: Use put_device() to give up your reference instead of freeing 30875739411aSCornelia Huck * @dev directly once you have called this function. 30881da177e4SLinus Torvalds */ 30891da177e4SLinus Torvalds void device_initialize(struct device *dev) 30901da177e4SLinus Torvalds { 3091881c6cfdSGreg Kroah-Hartman dev->kobj.kset = devices_kset; 3092f9cb074bSGreg Kroah-Hartman kobject_init(&dev->kobj, &device_ktype); 30931da177e4SLinus Torvalds INIT_LIST_HEAD(&dev->dma_pools); 30943142788bSThomas Gleixner mutex_init(&dev->mutex); 30951704f47bSPeter Zijlstra lockdep_set_novalidate_class(&dev->mutex); 30969ac7849eSTejun Heo spin_lock_init(&dev->devres_lock); 30979ac7849eSTejun Heo INIT_LIST_HEAD(&dev->devres_head); 30983b98aeafSAlan Stern device_pm_init(dev); 3099d460d7f7SMax Gurtovoy set_dev_node(dev, NUMA_NO_NODE); 31009ed98953SRafael J. Wysocki INIT_LIST_HEAD(&dev->links.consumers); 31019ed98953SRafael J. Wysocki INIT_LIST_HEAD(&dev->links.suppliers); 31023b052a3eSSaravana Kannan INIT_LIST_HEAD(&dev->links.defer_sync); 31039ed98953SRafael J. Wysocki dev->links.status = DL_DEV_NO_DRIVER; 31046d4e9a8eSChristoph Hellwig #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \ 31056d4e9a8eSChristoph Hellwig defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \ 31066d4e9a8eSChristoph Hellwig defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) 31076d4e9a8eSChristoph Hellwig dev->dma_coherent = dma_default_coherent; 31086d4e9a8eSChristoph Hellwig #endif 310969031f50SClaire Chang #ifdef CONFIG_SWIOTLB 3110463e862aSWill Deacon dev->dma_io_tlb_mem = &io_tlb_default_mem; 311169031f50SClaire Chang #endif 31121da177e4SLinus Torvalds } 311386df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_initialize); 31141da177e4SLinus Torvalds 3115d73ce004STejun Heo struct kobject *virtual_device_parent(struct device *dev) 3116f0ee61a6SGreg Kroah-Hartman { 3117f0ee61a6SGreg Kroah-Hartman static struct kobject *virtual_dir = NULL; 3118f0ee61a6SGreg Kroah-Hartman 3119f0ee61a6SGreg Kroah-Hartman if (!virtual_dir) 31204ff6abffSGreg Kroah-Hartman virtual_dir = kobject_create_and_add("virtual", 3121881c6cfdSGreg Kroah-Hartman &devices_kset->kobj); 3122f0ee61a6SGreg Kroah-Hartman 312386406245SKay Sievers return virtual_dir; 3124f0ee61a6SGreg Kroah-Hartman } 3125f0ee61a6SGreg Kroah-Hartman 3126bc451f20SEric W. Biederman struct class_dir { 3127bc451f20SEric W. Biederman struct kobject kobj; 31289fa120fbSGreg Kroah-Hartman const struct class *class; 3129bc451f20SEric W. Biederman }; 3130bc451f20SEric W. Biederman 3131bc451f20SEric W. Biederman #define to_class_dir(obj) container_of(obj, struct class_dir, kobj) 3132bc451f20SEric W. Biederman 3133bc451f20SEric W. Biederman static void class_dir_release(struct kobject *kobj) 3134bc451f20SEric W. Biederman { 3135bc451f20SEric W. Biederman struct class_dir *dir = to_class_dir(kobj); 3136bc451f20SEric W. Biederman kfree(dir); 3137bc451f20SEric W. Biederman } 3138bc451f20SEric W. Biederman 3139bc451f20SEric W. Biederman static const 314002a476d9SGreg Kroah-Hartman struct kobj_ns_type_operations *class_dir_child_ns_type(const struct kobject *kobj) 3141bc451f20SEric W. Biederman { 314202a476d9SGreg Kroah-Hartman const struct class_dir *dir = to_class_dir(kobj); 3143bc451f20SEric W. Biederman return dir->class->ns_type; 3144bc451f20SEric W. Biederman } 3145bc451f20SEric W. Biederman 3146c83d9ab4SThomas Weißschuh static const struct kobj_type class_dir_ktype = { 3147bc451f20SEric W. Biederman .release = class_dir_release, 3148bc451f20SEric W. Biederman .sysfs_ops = &kobj_sysfs_ops, 3149bc451f20SEric W. Biederman .child_ns_type = class_dir_child_ns_type 3150bc451f20SEric W. Biederman }; 3151bc451f20SEric W. Biederman 31527d90e81aSGreg Kroah-Hartman static struct kobject *class_dir_create_and_add(struct subsys_private *sp, 31537d90e81aSGreg Kroah-Hartman struct kobject *parent_kobj) 3154bc451f20SEric W. Biederman { 3155bc451f20SEric W. Biederman struct class_dir *dir; 3156bc451f20SEric W. Biederman int retval; 3157bc451f20SEric W. Biederman 3158bc451f20SEric W. Biederman dir = kzalloc(sizeof(*dir), GFP_KERNEL); 3159bc451f20SEric W. Biederman if (!dir) 316084d0c27dSTetsuo Handa return ERR_PTR(-ENOMEM); 3161bc451f20SEric W. Biederman 31627d90e81aSGreg Kroah-Hartman dir->class = sp->class; 3163bc451f20SEric W. Biederman kobject_init(&dir->kobj, &class_dir_ktype); 3164bc451f20SEric W. Biederman 31657d90e81aSGreg Kroah-Hartman dir->kobj.kset = &sp->glue_dirs; 3166bc451f20SEric W. Biederman 31677d90e81aSGreg Kroah-Hartman retval = kobject_add(&dir->kobj, parent_kobj, "%s", sp->class->name); 3168bc451f20SEric W. Biederman if (retval < 0) { 3169bc451f20SEric W. Biederman kobject_put(&dir->kobj); 317084d0c27dSTetsuo Handa return ERR_PTR(retval); 3171bc451f20SEric W. Biederman } 3172bc451f20SEric W. Biederman return &dir->kobj; 3173bc451f20SEric W. Biederman } 3174bc451f20SEric W. Biederman 3175e4a60d13SYijing Wang static DEFINE_MUTEX(gdp_mutex); 3176bc451f20SEric W. Biederman 3177c744aeaeSCornelia Huck static struct kobject *get_device_parent(struct device *dev, 3178c744aeaeSCornelia Huck struct device *parent) 317940fa5422SGreg Kroah-Hartman { 31807d90e81aSGreg Kroah-Hartman struct subsys_private *sp = class_to_subsys(dev->class); 318186406245SKay Sievers struct kobject *kobj = NULL; 31828c99377eSGreg Kroah-Hartman 31837d90e81aSGreg Kroah-Hartman if (sp) { 318486406245SKay Sievers struct kobject *parent_kobj; 318586406245SKay Sievers struct kobject *k; 318686406245SKay Sievers 318786406245SKay Sievers /* 318886406245SKay Sievers * If we have no parent, we live in "virtual". 31890f4dafc0SKay Sievers * Class-devices with a non class-device as parent, live 31900f4dafc0SKay Sievers * in a "glue" directory to prevent namespace collisions. 319186406245SKay Sievers */ 319286406245SKay Sievers if (parent == NULL) 319386406245SKay Sievers parent_kobj = virtual_device_parent(dev); 31947d90e81aSGreg Kroah-Hartman else if (parent->class && !dev->class->ns_type) { 31957d90e81aSGreg Kroah-Hartman subsys_put(sp); 319686406245SKay Sievers return &parent->kobj; 31977d90e81aSGreg Kroah-Hartman } else { 319886406245SKay Sievers parent_kobj = &parent->kobj; 31997d90e81aSGreg Kroah-Hartman } 320086406245SKay Sievers 320177d3d7c1STejun Heo mutex_lock(&gdp_mutex); 320277d3d7c1STejun Heo 320386406245SKay Sievers /* find our class-directory at the parent and reference it */ 32047d90e81aSGreg Kroah-Hartman spin_lock(&sp->glue_dirs.list_lock); 32057d90e81aSGreg Kroah-Hartman list_for_each_entry(k, &sp->glue_dirs.list, entry) 320686406245SKay Sievers if (k->parent == parent_kobj) { 320786406245SKay Sievers kobj = kobject_get(k); 320886406245SKay Sievers break; 320986406245SKay Sievers } 32107d90e81aSGreg Kroah-Hartman spin_unlock(&sp->glue_dirs.list_lock); 321177d3d7c1STejun Heo if (kobj) { 321277d3d7c1STejun Heo mutex_unlock(&gdp_mutex); 32137d90e81aSGreg Kroah-Hartman subsys_put(sp); 321486406245SKay Sievers return kobj; 321577d3d7c1STejun Heo } 321686406245SKay Sievers 321786406245SKay Sievers /* or create a new class-directory at the parent device */ 32187d90e81aSGreg Kroah-Hartman k = class_dir_create_and_add(sp, parent_kobj); 32190f4dafc0SKay Sievers /* do not emit an uevent for this simple "glue" directory */ 322077d3d7c1STejun Heo mutex_unlock(&gdp_mutex); 32217d90e81aSGreg Kroah-Hartman subsys_put(sp); 322243968d2fSGreg Kroah-Hartman return k; 322386406245SKay Sievers } 322486406245SKay Sievers 3225ca22e56dSKay Sievers /* subsystems can specify a default root directory for their devices */ 32268c99377eSGreg Kroah-Hartman if (!parent && dev->bus) { 32278c99377eSGreg Kroah-Hartman struct device *dev_root = bus_get_dev_root(dev->bus); 32288c99377eSGreg Kroah-Hartman 32298c99377eSGreg Kroah-Hartman if (dev_root) { 32308c99377eSGreg Kroah-Hartman kobj = &dev_root->kobj; 32318c99377eSGreg Kroah-Hartman put_device(dev_root); 32328c99377eSGreg Kroah-Hartman return kobj; 32338c99377eSGreg Kroah-Hartman } 32348c99377eSGreg Kroah-Hartman } 3235ca22e56dSKay Sievers 323686406245SKay Sievers if (parent) 3237c744aeaeSCornelia Huck return &parent->kobj; 3238c744aeaeSCornelia Huck return NULL; 3239c744aeaeSCornelia Huck } 3240da231fd5SKay Sievers 3241cebf8fd1SMing Lei static inline bool live_in_glue_dir(struct kobject *kobj, 3242cebf8fd1SMing Lei struct device *dev) 3243cebf8fd1SMing Lei { 32447d90e81aSGreg Kroah-Hartman struct subsys_private *sp; 32457d90e81aSGreg Kroah-Hartman bool retval; 32467d90e81aSGreg Kroah-Hartman 32477d90e81aSGreg Kroah-Hartman if (!kobj || !dev->class) 3248cebf8fd1SMing Lei return false; 32497d90e81aSGreg Kroah-Hartman 32507d90e81aSGreg Kroah-Hartman sp = class_to_subsys(dev->class); 32517d90e81aSGreg Kroah-Hartman if (!sp) 32527d90e81aSGreg Kroah-Hartman return false; 32537d90e81aSGreg Kroah-Hartman 32547d90e81aSGreg Kroah-Hartman if (kobj->kset == &sp->glue_dirs) 32557d90e81aSGreg Kroah-Hartman retval = true; 32567d90e81aSGreg Kroah-Hartman else 32577d90e81aSGreg Kroah-Hartman retval = false; 32587d90e81aSGreg Kroah-Hartman 32597d90e81aSGreg Kroah-Hartman subsys_put(sp); 32607d90e81aSGreg Kroah-Hartman return retval; 3261cebf8fd1SMing Lei } 3262cebf8fd1SMing Lei 3263cebf8fd1SMing Lei static inline struct kobject *get_glue_dir(struct device *dev) 3264cebf8fd1SMing Lei { 3265cebf8fd1SMing Lei return dev->kobj.parent; 3266cebf8fd1SMing Lei } 3267cebf8fd1SMing Lei 3268f0832664SIngo Molnar /** 3269f0832664SIngo Molnar * kobject_has_children - Returns whether a kobject has children. 3270f0832664SIngo Molnar * @kobj: the object to test 3271f0832664SIngo Molnar * 3272f0832664SIngo Molnar * This will return whether a kobject has other kobjects as children. 3273f0832664SIngo Molnar * 3274f0832664SIngo Molnar * It does NOT account for the presence of attribute files, only sub 3275f0832664SIngo Molnar * directories. It also assumes there is no concurrent addition or 3276f0832664SIngo Molnar * removal of such children, and thus relies on external locking. 3277f0832664SIngo Molnar */ 3278f0832664SIngo Molnar static inline bool kobject_has_children(struct kobject *kobj) 3279f0832664SIngo Molnar { 3280f0832664SIngo Molnar WARN_ON_ONCE(kref_read(&kobj->kref) == 0); 3281f0832664SIngo Molnar 3282f0832664SIngo Molnar return kobj->sd && kobj->sd->dir.subdirs; 3283f0832664SIngo Molnar } 3284f0832664SIngo Molnar 3285cebf8fd1SMing Lei /* 3286cebf8fd1SMing Lei * make sure cleaning up dir as the last step, we need to make 3287cebf8fd1SMing Lei * sure .release handler of kobject is run with holding the 3288cebf8fd1SMing Lei * global lock 3289cebf8fd1SMing Lei */ 329063b6971aSCornelia Huck static void cleanup_glue_dir(struct device *dev, struct kobject *glue_dir) 3291da231fd5SKay Sievers { 3292ac43432cSMuchun Song unsigned int ref; 3293ac43432cSMuchun Song 32940f4dafc0SKay Sievers /* see if we live in a "glue" directory */ 3295cebf8fd1SMing Lei if (!live_in_glue_dir(glue_dir, dev)) 3296da231fd5SKay Sievers return; 3297da231fd5SKay Sievers 3298e4a60d13SYijing Wang mutex_lock(&gdp_mutex); 3299ac43432cSMuchun Song /** 3300ac43432cSMuchun Song * There is a race condition between removing glue directory 3301ac43432cSMuchun Song * and adding a new device under the glue directory. 3302ac43432cSMuchun Song * 3303ac43432cSMuchun Song * CPU1: CPU2: 3304ac43432cSMuchun Song * 3305ac43432cSMuchun Song * device_add() 3306ac43432cSMuchun Song * get_device_parent() 3307ac43432cSMuchun Song * class_dir_create_and_add() 3308ac43432cSMuchun Song * kobject_add_internal() 3309ac43432cSMuchun Song * create_dir() // create glue_dir 3310ac43432cSMuchun Song * 3311ac43432cSMuchun Song * device_add() 3312ac43432cSMuchun Song * get_device_parent() 3313ac43432cSMuchun Song * kobject_get() // get glue_dir 3314ac43432cSMuchun Song * 3315ac43432cSMuchun Song * device_del() 3316ac43432cSMuchun Song * cleanup_glue_dir() 3317ac43432cSMuchun Song * kobject_del(glue_dir) 3318ac43432cSMuchun Song * 3319ac43432cSMuchun Song * kobject_add() 3320ac43432cSMuchun Song * kobject_add_internal() 3321ac43432cSMuchun Song * create_dir() // in glue_dir 3322ac43432cSMuchun Song * sysfs_create_dir_ns() 3323ac43432cSMuchun Song * kernfs_create_dir_ns(sd) 3324ac43432cSMuchun Song * 3325ac43432cSMuchun Song * sysfs_remove_dir() // glue_dir->sd=NULL 3326ac43432cSMuchun Song * sysfs_put() // free glue_dir->sd 3327ac43432cSMuchun Song * 3328ac43432cSMuchun Song * // sd is freed 3329ac43432cSMuchun Song * kernfs_new_node(sd) 3330ac43432cSMuchun Song * kernfs_get(glue_dir) 3331ac43432cSMuchun Song * kernfs_add_one() 3332ac43432cSMuchun Song * kernfs_put() 3333ac43432cSMuchun Song * 3334ac43432cSMuchun Song * Before CPU1 remove last child device under glue dir, if CPU2 add 3335ac43432cSMuchun Song * a new device under glue dir, the glue_dir kobject reference count 3336ac43432cSMuchun Song * will be increase to 2 in kobject_get(k). And CPU2 has been called 3337ac43432cSMuchun Song * kernfs_create_dir_ns(). Meanwhile, CPU1 call sysfs_remove_dir() 3338ac43432cSMuchun Song * and sysfs_put(). This result in glue_dir->sd is freed. 3339ac43432cSMuchun Song * 3340ac43432cSMuchun Song * Then the CPU2 will see a stale "empty" but still potentially used 3341ac43432cSMuchun Song * glue dir around in kernfs_new_node(). 3342ac43432cSMuchun Song * 3343ac43432cSMuchun Song * In order to avoid this happening, we also should make sure that 3344ac43432cSMuchun Song * kernfs_node for glue_dir is released in CPU1 only when refcount 3345ac43432cSMuchun Song * for glue_dir kobj is 1. 3346ac43432cSMuchun Song */ 3347ac43432cSMuchun Song ref = kref_read(&glue_dir->kref); 3348ac43432cSMuchun Song if (!kobject_has_children(glue_dir) && !--ref) 3349726e4109SBenjamin Herrenschmidt kobject_del(glue_dir); 33500f4dafc0SKay Sievers kobject_put(glue_dir); 3351e4a60d13SYijing Wang mutex_unlock(&gdp_mutex); 3352da231fd5SKay Sievers } 335363b6971aSCornelia Huck 33542ee97cafSCornelia Huck static int device_add_class_symlinks(struct device *dev) 33552ee97cafSCornelia Huck { 33565590f319SBenjamin Herrenschmidt struct device_node *of_node = dev_of_node(dev); 33577d90e81aSGreg Kroah-Hartman struct subsys_private *sp; 33582ee97cafSCornelia Huck int error; 33592ee97cafSCornelia Huck 33605590f319SBenjamin Herrenschmidt if (of_node) { 33610c3c234bSRob Herring error = sysfs_create_link(&dev->kobj, of_node_kobj(of_node), "of_node"); 33625590f319SBenjamin Herrenschmidt if (error) 33635590f319SBenjamin Herrenschmidt dev_warn(dev, "Error %d creating of_node link\n",error); 33645590f319SBenjamin Herrenschmidt /* An error here doesn't warrant bringing down the device */ 33655590f319SBenjamin Herrenschmidt } 33665590f319SBenjamin Herrenschmidt 33677d90e81aSGreg Kroah-Hartman sp = class_to_subsys(dev->class); 33687d90e81aSGreg Kroah-Hartman if (!sp) 33692ee97cafSCornelia Huck return 0; 3370da231fd5SKay Sievers 33717d90e81aSGreg Kroah-Hartman error = sysfs_create_link(&dev->kobj, &sp->subsys.kobj, "subsystem"); 33722ee97cafSCornelia Huck if (error) 33735590f319SBenjamin Herrenschmidt goto out_devnode; 3374da231fd5SKay Sievers 33754e886c29SGreg Kroah-Hartman if (dev->parent && device_is_not_partition(dev)) { 33764f01a757SDmitry Torokhov error = sysfs_create_link(&dev->kobj, &dev->parent->kobj, 33774f01a757SDmitry Torokhov "device"); 33784f01a757SDmitry Torokhov if (error) 337939aba963SKay Sievers goto out_subsys; 33802ee97cafSCornelia Huck } 338139aba963SKay Sievers 338239aba963SKay Sievers /* link in the class directory pointing to the device */ 33837d90e81aSGreg Kroah-Hartman error = sysfs_create_link(&sp->subsys.kobj, &dev->kobj, dev_name(dev)); 338439aba963SKay Sievers if (error) 338539aba963SKay Sievers goto out_device; 33867d90e81aSGreg Kroah-Hartman goto exit; 33872ee97cafSCornelia Huck 338839aba963SKay Sievers out_device: 338939aba963SKay Sievers sysfs_remove_link(&dev->kobj, "device"); 33902ee97cafSCornelia Huck out_subsys: 33912ee97cafSCornelia Huck sysfs_remove_link(&dev->kobj, "subsystem"); 33925590f319SBenjamin Herrenschmidt out_devnode: 33935590f319SBenjamin Herrenschmidt sysfs_remove_link(&dev->kobj, "of_node"); 33947d90e81aSGreg Kroah-Hartman exit: 33957d90e81aSGreg Kroah-Hartman subsys_put(sp); 33962ee97cafSCornelia Huck return error; 33972ee97cafSCornelia Huck } 33982ee97cafSCornelia Huck 33992ee97cafSCornelia Huck static void device_remove_class_symlinks(struct device *dev) 34002ee97cafSCornelia Huck { 34017d90e81aSGreg Kroah-Hartman struct subsys_private *sp = class_to_subsys(dev->class); 34027d90e81aSGreg Kroah-Hartman 34035590f319SBenjamin Herrenschmidt if (dev_of_node(dev)) 34045590f319SBenjamin Herrenschmidt sysfs_remove_link(&dev->kobj, "of_node"); 34055590f319SBenjamin Herrenschmidt 34067d90e81aSGreg Kroah-Hartman if (!sp) 34072ee97cafSCornelia Huck return; 3408da231fd5SKay Sievers 34094e886c29SGreg Kroah-Hartman if (dev->parent && device_is_not_partition(dev)) 3410da231fd5SKay Sievers sysfs_remove_link(&dev->kobj, "device"); 34112ee97cafSCornelia Huck sysfs_remove_link(&dev->kobj, "subsystem"); 34127d90e81aSGreg Kroah-Hartman sysfs_delete_link(&sp->subsys.kobj, &dev->kobj, dev_name(dev)); 34137d90e81aSGreg Kroah-Hartman subsys_put(sp); 34142ee97cafSCornelia Huck } 34152ee97cafSCornelia Huck 34161da177e4SLinus Torvalds /** 3417413c239fSStephen Rothwell * dev_set_name - set a device name 3418413c239fSStephen Rothwell * @dev: device 341946232366SRandy Dunlap * @fmt: format string for the device's name 3420413c239fSStephen Rothwell */ 3421413c239fSStephen Rothwell int dev_set_name(struct device *dev, const char *fmt, ...) 3422413c239fSStephen Rothwell { 3423413c239fSStephen Rothwell va_list vargs; 34241fa5ae85SKay Sievers int err; 3425413c239fSStephen Rothwell 3426413c239fSStephen Rothwell va_start(vargs, fmt); 34271fa5ae85SKay Sievers err = kobject_set_name_vargs(&dev->kobj, fmt, vargs); 3428413c239fSStephen Rothwell va_end(vargs); 34291fa5ae85SKay Sievers return err; 3430413c239fSStephen Rothwell } 3431413c239fSStephen Rothwell EXPORT_SYMBOL_GPL(dev_set_name); 3432413c239fSStephen Rothwell 3433*d6bdbbdfSGreg Kroah-Hartman /* select a /sys/dev/ directory for the device */ 3434e105b8bfSDan Williams static struct kobject *device_to_dev_kobj(struct device *dev) 3435e105b8bfSDan Williams { 3436*d6bdbbdfSGreg Kroah-Hartman if (is_blockdev(dev)) 3437*d6bdbbdfSGreg Kroah-Hartman return sysfs_dev_block_kobj; 3438e105b8bfSDan Williams else 3439*d6bdbbdfSGreg Kroah-Hartman return sysfs_dev_char_kobj; 3440e105b8bfSDan Williams } 3441e105b8bfSDan Williams 3442e105b8bfSDan Williams static int device_create_sys_dev_entry(struct device *dev) 3443e105b8bfSDan Williams { 3444e105b8bfSDan Williams struct kobject *kobj = device_to_dev_kobj(dev); 3445e105b8bfSDan Williams int error = 0; 3446e105b8bfSDan Williams char devt_str[15]; 3447e105b8bfSDan Williams 3448e105b8bfSDan Williams if (kobj) { 3449e105b8bfSDan Williams format_dev_t(devt_str, dev->devt); 3450e105b8bfSDan Williams error = sysfs_create_link(kobj, &dev->kobj, devt_str); 3451e105b8bfSDan Williams } 3452e105b8bfSDan Williams 3453e105b8bfSDan Williams return error; 3454e105b8bfSDan Williams } 3455e105b8bfSDan Williams 3456e105b8bfSDan Williams static void device_remove_sys_dev_entry(struct device *dev) 3457e105b8bfSDan Williams { 3458e105b8bfSDan Williams struct kobject *kobj = device_to_dev_kobj(dev); 3459e105b8bfSDan Williams char devt_str[15]; 3460e105b8bfSDan Williams 3461e105b8bfSDan Williams if (kobj) { 3462e105b8bfSDan Williams format_dev_t(devt_str, dev->devt); 3463e105b8bfSDan Williams sysfs_remove_link(kobj, devt_str); 3464e105b8bfSDan Williams } 3465e105b8bfSDan Williams } 3466e105b8bfSDan Williams 346746d3a037SShaokun Zhang static int device_private_init(struct device *dev) 3468b4028437SGreg Kroah-Hartman { 3469b4028437SGreg Kroah-Hartman dev->p = kzalloc(sizeof(*dev->p), GFP_KERNEL); 3470b4028437SGreg Kroah-Hartman if (!dev->p) 3471b4028437SGreg Kroah-Hartman return -ENOMEM; 3472b4028437SGreg Kroah-Hartman dev->p->device = dev; 3473b4028437SGreg Kroah-Hartman klist_init(&dev->p->klist_children, klist_children_get, 3474b4028437SGreg Kroah-Hartman klist_children_put); 3475ef8a3fd6SGreg Kroah-Hartman INIT_LIST_HEAD(&dev->p->deferred_probe); 3476b4028437SGreg Kroah-Hartman return 0; 3477b4028437SGreg Kroah-Hartman } 3478b4028437SGreg Kroah-Hartman 3479e105b8bfSDan Williams /** 34801da177e4SLinus Torvalds * device_add - add device to device hierarchy. 34811da177e4SLinus Torvalds * @dev: device. 34821da177e4SLinus Torvalds * 34831da177e4SLinus Torvalds * This is part 2 of device_register(), though may be called 34841da177e4SLinus Torvalds * separately _iff_ device_initialize() has been called separately. 34851da177e4SLinus Torvalds * 34865739411aSCornelia Huck * This adds @dev to the kobject hierarchy via kobject_add(), adds it 34871da177e4SLinus Torvalds * to the global and sibling lists for the device, then 34881da177e4SLinus Torvalds * adds it to the other relevant subsystems of the driver model. 34895739411aSCornelia Huck * 3490b10d5efdSAlan Stern * Do not call this routine or device_register() more than once for 3491b10d5efdSAlan Stern * any device structure. The driver model core is not designed to work 3492b10d5efdSAlan Stern * with devices that get unregistered and then spring back to life. 3493b10d5efdSAlan Stern * (Among other things, it's very hard to guarantee that all references 3494b10d5efdSAlan Stern * to the previous incarnation of @dev have been dropped.) Allocate 3495b10d5efdSAlan Stern * and register a fresh new struct device instead. 3496b10d5efdSAlan Stern * 34975739411aSCornelia Huck * NOTE: _Never_ directly free @dev after calling this function, even 34985739411aSCornelia Huck * if it returned an error! Always use put_device() to give up your 34995739411aSCornelia Huck * reference instead. 3500affada72SBorislav Petkov * 3501affada72SBorislav Petkov * Rule of thumb is: if device_add() succeeds, you should call 3502affada72SBorislav Petkov * device_del() when you want to get rid of it. If device_add() has 3503affada72SBorislav Petkov * *not* succeeded, use *only* put_device() to drop the reference 3504affada72SBorislav Petkov * count. 35051da177e4SLinus Torvalds */ 35061da177e4SLinus Torvalds int device_add(struct device *dev) 35071da177e4SLinus Torvalds { 35087d90e81aSGreg Kroah-Hartman struct subsys_private *sp; 350935dbf4efSViresh Kumar struct device *parent; 3510ca22e56dSKay Sievers struct kobject *kobj; 3511c47ed219SGreg Kroah-Hartman struct class_interface *class_intf; 35125f5377eaSSaravana Kannan int error = -EINVAL; 3513cebf8fd1SMing Lei struct kobject *glue_dir = NULL; 3514775b64d2SRafael J. Wysocki 35151da177e4SLinus Torvalds dev = get_device(dev); 3516c906a48aSGreg Kroah-Hartman if (!dev) 3517c906a48aSGreg Kroah-Hartman goto done; 3518c906a48aSGreg Kroah-Hartman 3519fb069a5dSGreg Kroah-Hartman if (!dev->p) { 3520b4028437SGreg Kroah-Hartman error = device_private_init(dev); 3521b4028437SGreg Kroah-Hartman if (error) 3522fb069a5dSGreg Kroah-Hartman goto done; 3523fb069a5dSGreg Kroah-Hartman } 3524fb069a5dSGreg Kroah-Hartman 35251fa5ae85SKay Sievers /* 35261fa5ae85SKay Sievers * for statically allocated devices, which should all be converted 35271fa5ae85SKay Sievers * some day, we need to initialize the name. We prevent reading back 35281fa5ae85SKay Sievers * the name, and force the use of dev_name() 35291fa5ae85SKay Sievers */ 35301fa5ae85SKay Sievers if (dev->init_name) { 3531acc0e90fSGreg Kroah-Hartman dev_set_name(dev, "%s", dev->init_name); 35321fa5ae85SKay Sievers dev->init_name = NULL; 35331fa5ae85SKay Sievers } 3534c906a48aSGreg Kroah-Hartman 3535ca22e56dSKay Sievers /* subsystems can specify simple device enumeration */ 3536ca22e56dSKay Sievers if (!dev_name(dev) && dev->bus && dev->bus->dev_name) 3537ca22e56dSKay Sievers dev_set_name(dev, "%s%u", dev->bus->dev_name, dev->id); 3538ca22e56dSKay Sievers 3539e6309e75SThomas Gleixner if (!dev_name(dev)) { 3540e6309e75SThomas Gleixner error = -EINVAL; 35415c8563d7SKay Sievers goto name_error; 3542e6309e75SThomas Gleixner } 35431da177e4SLinus Torvalds 35441e0b2cf9SKay Sievers pr_debug("device: '%s': %s\n", dev_name(dev), __func__); 3545c205ef48SGreg Kroah-Hartman 35461da177e4SLinus Torvalds parent = get_device(dev->parent); 3547ca22e56dSKay Sievers kobj = get_device_parent(dev, parent); 354884d0c27dSTetsuo Handa if (IS_ERR(kobj)) { 354984d0c27dSTetsuo Handa error = PTR_ERR(kobj); 355084d0c27dSTetsuo Handa goto parent_error; 355184d0c27dSTetsuo Handa } 3552ca22e56dSKay Sievers if (kobj) 3553ca22e56dSKay Sievers dev->kobj.parent = kobj; 35541da177e4SLinus Torvalds 35550d358f22SYinghai Lu /* use parent numa_node */ 355656f2de81SZhen Lei if (parent && (dev_to_node(dev) == NUMA_NO_NODE)) 35570d358f22SYinghai Lu set_dev_node(dev, dev_to_node(parent)); 35580d358f22SYinghai Lu 35591da177e4SLinus Torvalds /* first, register with generic layer. */ 35608a577ffcSKay Sievers /* we require the name to be set before, and pass NULL */ 35618a577ffcSKay Sievers error = kobject_add(&dev->kobj, dev->kobj.parent, NULL); 3562cebf8fd1SMing Lei if (error) { 35636977b1a5SZhengchao Shao glue_dir = kobj; 35641da177e4SLinus Torvalds goto Error; 3565cebf8fd1SMing Lei } 3566a7fd6706SKay Sievers 356737022644SBrian Walsh /* notify platform of device entry */ 3568b2ebd9ddSRafael J. Wysocki device_platform_notify(dev); 356937022644SBrian Walsh 3570c5e064a6SGreg Kroah-Hartman error = device_create_file(dev, &dev_attr_uevent); 3571a306eea4SCornelia Huck if (error) 3572a306eea4SCornelia Huck goto attrError; 3573a7fd6706SKay Sievers 35742ee97cafSCornelia Huck error = device_add_class_symlinks(dev); 35752ee97cafSCornelia Huck if (error) 35762ee97cafSCornelia Huck goto SymlinkError; 3577dc0afa83SCornelia Huck error = device_add_attrs(dev); 3578dc0afa83SCornelia Huck if (error) 35792620efefSGreg Kroah-Hartman goto AttrsError; 3580dc0afa83SCornelia Huck error = bus_add_device(dev); 3581dc0afa83SCornelia Huck if (error) 35821da177e4SLinus Torvalds goto BusError; 35833b98aeafSAlan Stern error = dpm_sysfs_add(dev); 358457eee3d2SRafael J. Wysocki if (error) 35853b98aeafSAlan Stern goto DPMError; 35863b98aeafSAlan Stern device_pm_add(dev); 3587ec0676eeSAlan Stern 35880cd75047SSergey Klyaus if (MAJOR(dev->devt)) { 35890cd75047SSergey Klyaus error = device_create_file(dev, &dev_attr_dev); 35900cd75047SSergey Klyaus if (error) 35910cd75047SSergey Klyaus goto DevAttrError; 35920cd75047SSergey Klyaus 35930cd75047SSergey Klyaus error = device_create_sys_dev_entry(dev); 35940cd75047SSergey Klyaus if (error) 35950cd75047SSergey Klyaus goto SysEntryError; 35960cd75047SSergey Klyaus 35970cd75047SSergey Klyaus devtmpfs_create_node(dev); 35980cd75047SSergey Klyaus } 35990cd75047SSergey Klyaus 3600ec0676eeSAlan Stern /* Notify clients of device addition. This call must come 3601268863f4Smajianpeng * after dpm_sysfs_add() and before kobject_uevent(). 3602ec0676eeSAlan Stern */ 3603ed9f9181SGreg Kroah-Hartman bus_notify(dev, BUS_NOTIFY_ADD_DEVICE); 360453877d06SKay Sievers kobject_uevent(&dev->kobj, KOBJ_ADD); 3605372a67c0SSaravana Kannan 3606e2ae9bccSSaravana Kannan /* 3607e2ae9bccSSaravana Kannan * Check if any of the other devices (consumers) have been waiting for 3608e2ae9bccSSaravana Kannan * this device (supplier) to be added so that they can create a device 3609e2ae9bccSSaravana Kannan * link to it. 3610e2ae9bccSSaravana Kannan * 3611e2ae9bccSSaravana Kannan * This needs to happen after device_pm_add() because device_link_add() 3612e2ae9bccSSaravana Kannan * requires the supplier be registered before it's called. 3613e2ae9bccSSaravana Kannan * 36142cd38fd1SSaravana Kannan * But this also needs to happen before bus_probe_device() to make sure 3615e2ae9bccSSaravana Kannan * waiting consumers can link to it before the driver is bound to the 3616e2ae9bccSSaravana Kannan * device and the driver sync_state callback is called for this device. 3617e2ae9bccSSaravana Kannan */ 36182cd38fd1SSaravana Kannan if (dev->fwnode && !dev->fwnode->dev) { 36192cd38fd1SSaravana Kannan dev->fwnode->dev = dev; 36205f5377eaSSaravana Kannan fw_devlink_link_device(dev); 362103324507SSaravana Kannan } 3622e2ae9bccSSaravana Kannan 36232023c610SAlan Stern bus_probe_device(dev); 3624d46f3e3eSSaravana Kannan 3625d46f3e3eSSaravana Kannan /* 3626d46f3e3eSSaravana Kannan * If all driver registration is done and a newly added device doesn't 3627d46f3e3eSSaravana Kannan * match with any driver, don't block its consumers from probing in 3628d46f3e3eSSaravana Kannan * case the consumer device is able to operate without this supplier. 3629d46f3e3eSSaravana Kannan */ 3630d46f3e3eSSaravana Kannan if (dev->fwnode && fw_devlink_drv_reg_done && !dev->can_match) 3631d46f3e3eSSaravana Kannan fw_devlink_unblock_consumers(dev); 3632d46f3e3eSSaravana Kannan 36331da177e4SLinus Torvalds if (parent) 3634f791b8c8SGreg Kroah-Hartman klist_add_tail(&dev->p->knode_parent, 3635f791b8c8SGreg Kroah-Hartman &parent->p->klist_children); 36361da177e4SLinus Torvalds 36377d90e81aSGreg Kroah-Hartman sp = class_to_subsys(dev->class); 36387d90e81aSGreg Kroah-Hartman if (sp) { 36397d90e81aSGreg Kroah-Hartman mutex_lock(&sp->mutex); 3640c47ed219SGreg Kroah-Hartman /* tie the class to the device */ 36417d90e81aSGreg Kroah-Hartman klist_add_tail(&dev->p->knode_class, &sp->klist_devices); 3642c47ed219SGreg Kroah-Hartman 3643c47ed219SGreg Kroah-Hartman /* notify any interfaces that the device is here */ 36447d90e81aSGreg Kroah-Hartman list_for_each_entry(class_intf, &sp->interfaces, node) 3645c47ed219SGreg Kroah-Hartman if (class_intf->add_dev) 3646c47ed219SGreg Kroah-Hartman class_intf->add_dev(dev, class_intf); 36477d90e81aSGreg Kroah-Hartman mutex_unlock(&sp->mutex); 36487d90e81aSGreg Kroah-Hartman subsys_put(sp); 36495d9fd169SGreg Kroah-Hartman } 3650c906a48aSGreg Kroah-Hartman done: 36511da177e4SLinus Torvalds put_device(dev); 36521da177e4SLinus Torvalds return error; 36530cd75047SSergey Klyaus SysEntryError: 36540cd75047SSergey Klyaus if (MAJOR(dev->devt)) 36550cd75047SSergey Klyaus device_remove_file(dev, &dev_attr_dev); 36560cd75047SSergey Klyaus DevAttrError: 36570cd75047SSergey Klyaus device_pm_remove(dev); 36580cd75047SSergey Klyaus dpm_sysfs_remove(dev); 36593b98aeafSAlan Stern DPMError: 3660f6837f34SYang Yingliang dev->driver = NULL; 366157eee3d2SRafael J. Wysocki bus_remove_device(dev); 366257eee3d2SRafael J. Wysocki BusError: 36632620efefSGreg Kroah-Hartman device_remove_attrs(dev); 36642620efefSGreg Kroah-Hartman AttrsError: 36652ee97cafSCornelia Huck device_remove_class_symlinks(dev); 36662ee97cafSCornelia Huck SymlinkError: 3667c5e064a6SGreg Kroah-Hartman device_remove_file(dev, &dev_attr_uevent); 366823681e47SGreg Kroah-Hartman attrError: 3669b2ebd9ddSRafael J. Wysocki device_platform_notify_remove(dev); 3670312c004dSKay Sievers kobject_uevent(&dev->kobj, KOBJ_REMOVE); 3671cebf8fd1SMing Lei glue_dir = get_glue_dir(dev); 36721da177e4SLinus Torvalds kobject_del(&dev->kobj); 36731da177e4SLinus Torvalds Error: 3674cebf8fd1SMing Lei cleanup_glue_dir(dev, glue_dir); 367584d0c27dSTetsuo Handa parent_error: 36761da177e4SLinus Torvalds put_device(parent); 36775c8563d7SKay Sievers name_error: 36785c8563d7SKay Sievers kfree(dev->p); 36795c8563d7SKay Sievers dev->p = NULL; 3680c906a48aSGreg Kroah-Hartman goto done; 36811da177e4SLinus Torvalds } 368286df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_add); 36831da177e4SLinus Torvalds 36841da177e4SLinus Torvalds /** 36851da177e4SLinus Torvalds * device_register - register a device with the system. 36861da177e4SLinus Torvalds * @dev: pointer to the device structure 36871da177e4SLinus Torvalds * 36881da177e4SLinus Torvalds * This happens in two clean steps - initialize the device 36891da177e4SLinus Torvalds * and add it to the system. The two steps can be called 36901da177e4SLinus Torvalds * separately, but this is the easiest and most common. 36911da177e4SLinus Torvalds * I.e. you should only call the two helpers separately if 36921da177e4SLinus Torvalds * have a clearly defined need to use and refcount the device 36931da177e4SLinus Torvalds * before it is added to the hierarchy. 36945739411aSCornelia Huck * 3695b10d5efdSAlan Stern * For more information, see the kerneldoc for device_initialize() 3696b10d5efdSAlan Stern * and device_add(). 3697b10d5efdSAlan Stern * 36985739411aSCornelia Huck * NOTE: _Never_ directly free @dev after calling this function, even 36995739411aSCornelia Huck * if it returned an error! Always use put_device() to give up the 37005739411aSCornelia Huck * reference initialized in this function instead. 37011da177e4SLinus Torvalds */ 37021da177e4SLinus Torvalds int device_register(struct device *dev) 37031da177e4SLinus Torvalds { 37041da177e4SLinus Torvalds device_initialize(dev); 37051da177e4SLinus Torvalds return device_add(dev); 37061da177e4SLinus Torvalds } 370786df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_register); 37081da177e4SLinus Torvalds 37091da177e4SLinus Torvalds /** 37101da177e4SLinus Torvalds * get_device - increment reference count for device. 37111da177e4SLinus Torvalds * @dev: device. 37121da177e4SLinus Torvalds * 37131da177e4SLinus Torvalds * This simply forwards the call to kobject_get(), though 37141da177e4SLinus Torvalds * we do take care to provide for the case that we get a NULL 37151da177e4SLinus Torvalds * pointer passed in. 37161da177e4SLinus Torvalds */ 37171da177e4SLinus Torvalds struct device *get_device(struct device *dev) 37181da177e4SLinus Torvalds { 3719b0d1f807SLars-Peter Clausen return dev ? kobj_to_dev(kobject_get(&dev->kobj)) : NULL; 37201da177e4SLinus Torvalds } 372186df2687SDavid Graham White EXPORT_SYMBOL_GPL(get_device); 37221da177e4SLinus Torvalds 37231da177e4SLinus Torvalds /** 37241da177e4SLinus Torvalds * put_device - decrement reference count. 37251da177e4SLinus Torvalds * @dev: device in question. 37261da177e4SLinus Torvalds */ 37271da177e4SLinus Torvalds void put_device(struct device *dev) 37281da177e4SLinus Torvalds { 3729edfaa7c3SKay Sievers /* might_sleep(); */ 37301da177e4SLinus Torvalds if (dev) 37311da177e4SLinus Torvalds kobject_put(&dev->kobj); 37321da177e4SLinus Torvalds } 373386df2687SDavid Graham White EXPORT_SYMBOL_GPL(put_device); 37341da177e4SLinus Torvalds 373500289cd8SDan Williams bool kill_device(struct device *dev) 373600289cd8SDan Williams { 373700289cd8SDan Williams /* 373800289cd8SDan Williams * Require the device lock and set the "dead" flag to guarantee that 373900289cd8SDan Williams * the update behavior is consistent with the other bitfields near 374000289cd8SDan Williams * it and that we cannot have an asynchronous probe routine trying 374100289cd8SDan Williams * to run while we are tearing out the bus/class/sysfs from 374200289cd8SDan Williams * underneath the device. 374300289cd8SDan Williams */ 37448c60a141SJulian Wiedmann device_lock_assert(dev); 374500289cd8SDan Williams 374600289cd8SDan Williams if (dev->p->dead) 374700289cd8SDan Williams return false; 374800289cd8SDan Williams dev->p->dead = true; 374900289cd8SDan Williams return true; 375000289cd8SDan Williams } 375100289cd8SDan Williams EXPORT_SYMBOL_GPL(kill_device); 375200289cd8SDan Williams 37531da177e4SLinus Torvalds /** 37541da177e4SLinus Torvalds * device_del - delete device from system. 37551da177e4SLinus Torvalds * @dev: device. 37561da177e4SLinus Torvalds * 37571da177e4SLinus Torvalds * This is the first part of the device unregistration 37581da177e4SLinus Torvalds * sequence. This removes the device from the lists we control 37591da177e4SLinus Torvalds * from here, has it removed from the other driver model 37601da177e4SLinus Torvalds * subsystems it was added to in device_add(), and removes it 37611da177e4SLinus Torvalds * from the kobject hierarchy. 37621da177e4SLinus Torvalds * 37631da177e4SLinus Torvalds * NOTE: this should be called manually _iff_ device_add() was 37641da177e4SLinus Torvalds * also called manually. 37651da177e4SLinus Torvalds */ 37661da177e4SLinus Torvalds void device_del(struct device *dev) 37671da177e4SLinus Torvalds { 37687d90e81aSGreg Kroah-Hartman struct subsys_private *sp; 37691da177e4SLinus Torvalds struct device *parent = dev->parent; 3770cebf8fd1SMing Lei struct kobject *glue_dir = NULL; 3771c47ed219SGreg Kroah-Hartman struct class_interface *class_intf; 3772b8530017SOliver Neukum unsigned int noio_flag; 37731da177e4SLinus Torvalds 37743451a495SAlexander Duyck device_lock(dev); 377500289cd8SDan Williams kill_device(dev); 37763451a495SAlexander Duyck device_unlock(dev); 37773451a495SAlexander Duyck 3778372a67c0SSaravana Kannan if (dev->fwnode && dev->fwnode->dev == dev) 3779372a67c0SSaravana Kannan dev->fwnode->dev = NULL; 3780372a67c0SSaravana Kannan 3781ec0676eeSAlan Stern /* Notify clients of device removal. This call must come 3782ec0676eeSAlan Stern * before dpm_sysfs_remove(). 3783ec0676eeSAlan Stern */ 3784b8530017SOliver Neukum noio_flag = memalloc_noio_save(); 3785ed9f9181SGreg Kroah-Hartman bus_notify(dev, BUS_NOTIFY_DEL_DEVICE); 37869ed98953SRafael J. Wysocki 37873b98aeafSAlan Stern dpm_sysfs_remove(dev); 37881da177e4SLinus Torvalds if (parent) 3789f791b8c8SGreg Kroah-Hartman klist_del(&dev->p->knode_parent); 3790e105b8bfSDan Williams if (MAJOR(dev->devt)) { 37912b2af54aSKay Sievers devtmpfs_delete_node(dev); 3792e105b8bfSDan Williams device_remove_sys_dev_entry(dev); 3793c5e064a6SGreg Kroah-Hartman device_remove_file(dev, &dev_attr_dev); 3794e105b8bfSDan Williams } 37957d90e81aSGreg Kroah-Hartman 37967d90e81aSGreg Kroah-Hartman sp = class_to_subsys(dev->class); 37977d90e81aSGreg Kroah-Hartman if (sp) { 3798da231fd5SKay Sievers device_remove_class_symlinks(dev); 379999ef3ef8SKay Sievers 38007d90e81aSGreg Kroah-Hartman mutex_lock(&sp->mutex); 3801c47ed219SGreg Kroah-Hartman /* notify any interfaces that the device is now gone */ 38027d90e81aSGreg Kroah-Hartman list_for_each_entry(class_intf, &sp->interfaces, node) 3803c47ed219SGreg Kroah-Hartman if (class_intf->remove_dev) 3804c47ed219SGreg Kroah-Hartman class_intf->remove_dev(dev, class_intf); 3805c47ed219SGreg Kroah-Hartman /* remove the device from the class list */ 3806570d0200SWei Yang klist_del(&dev->p->knode_class); 38077d90e81aSGreg Kroah-Hartman mutex_unlock(&sp->mutex); 38087d90e81aSGreg Kroah-Hartman subsys_put(sp); 3809b9d9c82bSKay Sievers } 3810c5e064a6SGreg Kroah-Hartman device_remove_file(dev, &dev_attr_uevent); 38112620efefSGreg Kroah-Hartman device_remove_attrs(dev); 381228953533SBenjamin Herrenschmidt bus_remove_device(dev); 38134b6d1f12SLongX Zhang device_pm_remove(dev); 3814d1c3414cSGrant Likely driver_deferred_probe_del(dev); 3815b2ebd9ddSRafael J. Wysocki device_platform_notify_remove(dev); 38162ec16150SJeffy Chen device_links_purge(dev); 38171da177e4SLinus Torvalds 3818ed9f9181SGreg Kroah-Hartman bus_notify(dev, BUS_NOTIFY_REMOVED_DEVICE); 3819312c004dSKay Sievers kobject_uevent(&dev->kobj, KOBJ_REMOVE); 3820cebf8fd1SMing Lei glue_dir = get_glue_dir(dev); 38211da177e4SLinus Torvalds kobject_del(&dev->kobj); 3822cebf8fd1SMing Lei cleanup_glue_dir(dev, glue_dir); 3823b8530017SOliver Neukum memalloc_noio_restore(noio_flag); 38241da177e4SLinus Torvalds put_device(parent); 38251da177e4SLinus Torvalds } 382686df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_del); 38271da177e4SLinus Torvalds 38281da177e4SLinus Torvalds /** 38291da177e4SLinus Torvalds * device_unregister - unregister device from system. 38301da177e4SLinus Torvalds * @dev: device going away. 38311da177e4SLinus Torvalds * 38321da177e4SLinus Torvalds * We do this in two parts, like we do device_register(). First, 38331da177e4SLinus Torvalds * we remove it from all the subsystems with device_del(), then 38341da177e4SLinus Torvalds * we decrement the reference count via put_device(). If that 38351da177e4SLinus Torvalds * is the final reference count, the device will be cleaned up 38361da177e4SLinus Torvalds * via device_release() above. Otherwise, the structure will 38371da177e4SLinus Torvalds * stick around until the final reference to the device is dropped. 38381da177e4SLinus Torvalds */ 38391da177e4SLinus Torvalds void device_unregister(struct device *dev) 38401da177e4SLinus Torvalds { 38411e0b2cf9SKay Sievers pr_debug("device: '%s': %s\n", dev_name(dev), __func__); 38421da177e4SLinus Torvalds device_del(dev); 38431da177e4SLinus Torvalds put_device(dev); 38441da177e4SLinus Torvalds } 384586df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_unregister); 38461da177e4SLinus Torvalds 38473d060aebSAndy Shevchenko static struct device *prev_device(struct klist_iter *i) 38483d060aebSAndy Shevchenko { 38493d060aebSAndy Shevchenko struct klist_node *n = klist_prev(i); 38503d060aebSAndy Shevchenko struct device *dev = NULL; 38513d060aebSAndy Shevchenko struct device_private *p; 38523d060aebSAndy Shevchenko 38533d060aebSAndy Shevchenko if (n) { 38543d060aebSAndy Shevchenko p = to_device_private_parent(n); 38553d060aebSAndy Shevchenko dev = p->device; 38563d060aebSAndy Shevchenko } 38573d060aebSAndy Shevchenko return dev; 38583d060aebSAndy Shevchenko } 38593d060aebSAndy Shevchenko 386036239577Smochel@digitalimplant.org static struct device *next_device(struct klist_iter *i) 386136239577Smochel@digitalimplant.org { 386236239577Smochel@digitalimplant.org struct klist_node *n = klist_next(i); 3863f791b8c8SGreg Kroah-Hartman struct device *dev = NULL; 3864f791b8c8SGreg Kroah-Hartman struct device_private *p; 3865f791b8c8SGreg Kroah-Hartman 3866f791b8c8SGreg Kroah-Hartman if (n) { 3867f791b8c8SGreg Kroah-Hartman p = to_device_private_parent(n); 3868f791b8c8SGreg Kroah-Hartman dev = p->device; 3869f791b8c8SGreg Kroah-Hartman } 3870f791b8c8SGreg Kroah-Hartman return dev; 387136239577Smochel@digitalimplant.org } 387236239577Smochel@digitalimplant.org 38731da177e4SLinus Torvalds /** 3874e454cea2SKay Sievers * device_get_devnode - path of device node file 38756fcf53acSKay Sievers * @dev: device 3876e454cea2SKay Sievers * @mode: returned file access mode 38773c2670e6SKay Sievers * @uid: returned file owner 38783c2670e6SKay Sievers * @gid: returned file group 38796fcf53acSKay Sievers * @tmp: possibly allocated string 38806fcf53acSKay Sievers * 38816fcf53acSKay Sievers * Return the relative path of a possible device node. 38826fcf53acSKay Sievers * Non-default names may need to allocate a memory to compose 38836fcf53acSKay Sievers * a name. This memory is returned in tmp and needs to be 38846fcf53acSKay Sievers * freed by the caller. 38856fcf53acSKay Sievers */ 388642bb5be8SGreg Kroah-Hartman const char *device_get_devnode(const struct device *dev, 38874e4098a3SGreg Kroah-Hartman umode_t *mode, kuid_t *uid, kgid_t *gid, 38883c2670e6SKay Sievers const char **tmp) 38896fcf53acSKay Sievers { 38906fcf53acSKay Sievers char *s; 38916fcf53acSKay Sievers 38926fcf53acSKay Sievers *tmp = NULL; 38936fcf53acSKay Sievers 38946fcf53acSKay Sievers /* the device type may provide a specific name */ 3895e454cea2SKay Sievers if (dev->type && dev->type->devnode) 38963c2670e6SKay Sievers *tmp = dev->type->devnode(dev, mode, uid, gid); 38976fcf53acSKay Sievers if (*tmp) 38986fcf53acSKay Sievers return *tmp; 38996fcf53acSKay Sievers 39006fcf53acSKay Sievers /* the class may provide a specific name */ 3901e454cea2SKay Sievers if (dev->class && dev->class->devnode) 3902e454cea2SKay Sievers *tmp = dev->class->devnode(dev, mode); 39036fcf53acSKay Sievers if (*tmp) 39046fcf53acSKay Sievers return *tmp; 39056fcf53acSKay Sievers 39066fcf53acSKay Sievers /* return name without allocation, tmp == NULL */ 39076fcf53acSKay Sievers if (strchr(dev_name(dev), '!') == NULL) 39086fcf53acSKay Sievers return dev_name(dev); 39096fcf53acSKay Sievers 39106fcf53acSKay Sievers /* replace '!' in the name with '/' */ 3911a29fd614SRasmus Villemoes s = kstrdup(dev_name(dev), GFP_KERNEL); 3912a29fd614SRasmus Villemoes if (!s) 39136fcf53acSKay Sievers return NULL; 3914a29fd614SRasmus Villemoes strreplace(s, '!', '/'); 3915a29fd614SRasmus Villemoes return *tmp = s; 39166fcf53acSKay Sievers } 39176fcf53acSKay Sievers 39186fcf53acSKay Sievers /** 39191da177e4SLinus Torvalds * device_for_each_child - device child iterator. 3920c41455fbSRandy Dunlap * @parent: parent struct device. 39211da177e4SLinus Torvalds * @fn: function to be called for each device. 3922f8878dcbSRobert P. J. Day * @data: data for the callback. 39231da177e4SLinus Torvalds * 3924c41455fbSRandy Dunlap * Iterate over @parent's child devices, and call @fn for each, 39251da177e4SLinus Torvalds * passing it @data. 39261da177e4SLinus Torvalds * 39271da177e4SLinus Torvalds * We check the return of @fn each time. If it returns anything 39281da177e4SLinus Torvalds * other than 0, we break out and return that value. 39291da177e4SLinus Torvalds */ 393036239577Smochel@digitalimplant.org int device_for_each_child(struct device *parent, void *data, 39314a3ad20cSGreg Kroah-Hartman int (*fn)(struct device *dev, void *data)) 39321da177e4SLinus Torvalds { 393336239577Smochel@digitalimplant.org struct klist_iter i; 39341da177e4SLinus Torvalds struct device *child; 39351da177e4SLinus Torvalds int error = 0; 39361da177e4SLinus Torvalds 3937014c90dbSGreg Kroah-Hartman if (!parent->p) 3938014c90dbSGreg Kroah-Hartman return 0; 3939014c90dbSGreg Kroah-Hartman 3940f791b8c8SGreg Kroah-Hartman klist_iter_init(&parent->p->klist_children, &i); 394193ead7c9SGimcuan Hui while (!error && (child = next_device(&i))) 394236239577Smochel@digitalimplant.org error = fn(child, data); 394336239577Smochel@digitalimplant.org klist_iter_exit(&i); 39441da177e4SLinus Torvalds return error; 39451da177e4SLinus Torvalds } 394686df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_for_each_child); 39471da177e4SLinus Torvalds 39485ab69981SCornelia Huck /** 39493d060aebSAndy Shevchenko * device_for_each_child_reverse - device child iterator in reversed order. 39503d060aebSAndy Shevchenko * @parent: parent struct device. 39513d060aebSAndy Shevchenko * @fn: function to be called for each device. 39523d060aebSAndy Shevchenko * @data: data for the callback. 39533d060aebSAndy Shevchenko * 39543d060aebSAndy Shevchenko * Iterate over @parent's child devices, and call @fn for each, 39553d060aebSAndy Shevchenko * passing it @data. 39563d060aebSAndy Shevchenko * 39573d060aebSAndy Shevchenko * We check the return of @fn each time. If it returns anything 39583d060aebSAndy Shevchenko * other than 0, we break out and return that value. 39593d060aebSAndy Shevchenko */ 39603d060aebSAndy Shevchenko int device_for_each_child_reverse(struct device *parent, void *data, 39613d060aebSAndy Shevchenko int (*fn)(struct device *dev, void *data)) 39623d060aebSAndy Shevchenko { 39633d060aebSAndy Shevchenko struct klist_iter i; 39643d060aebSAndy Shevchenko struct device *child; 39653d060aebSAndy Shevchenko int error = 0; 39663d060aebSAndy Shevchenko 39673d060aebSAndy Shevchenko if (!parent->p) 39683d060aebSAndy Shevchenko return 0; 39693d060aebSAndy Shevchenko 39703d060aebSAndy Shevchenko klist_iter_init(&parent->p->klist_children, &i); 39713d060aebSAndy Shevchenko while ((child = prev_device(&i)) && !error) 39723d060aebSAndy Shevchenko error = fn(child, data); 39733d060aebSAndy Shevchenko klist_iter_exit(&i); 39743d060aebSAndy Shevchenko return error; 39753d060aebSAndy Shevchenko } 39763d060aebSAndy Shevchenko EXPORT_SYMBOL_GPL(device_for_each_child_reverse); 39773d060aebSAndy Shevchenko 39783d060aebSAndy Shevchenko /** 39795ab69981SCornelia Huck * device_find_child - device iterator for locating a particular device. 39805ab69981SCornelia Huck * @parent: parent struct device 39815ab69981SCornelia Huck * @match: Callback function to check device 3982f8878dcbSRobert P. J. Day * @data: Data to pass to match function 39835ab69981SCornelia Huck * 39845ab69981SCornelia Huck * This is similar to the device_for_each_child() function above, but it 39855ab69981SCornelia Huck * returns a reference to a device that is 'found' for later use, as 39865ab69981SCornelia Huck * determined by the @match callback. 39875ab69981SCornelia Huck * 39885ab69981SCornelia Huck * The callback should return 0 if the device doesn't match and non-zero 39895ab69981SCornelia Huck * if it does. If the callback returns non-zero and a reference to the 39905ab69981SCornelia Huck * current device can be obtained, this function will return to the caller 39915ab69981SCornelia Huck * and not iterate over any more devices. 3992a4e2400aSFederico Vaga * 3993a4e2400aSFederico Vaga * NOTE: you will need to drop the reference with put_device() after use. 39945ab69981SCornelia Huck */ 39955ab69981SCornelia Huck struct device *device_find_child(struct device *parent, void *data, 39964a3ad20cSGreg Kroah-Hartman int (*match)(struct device *dev, void *data)) 39975ab69981SCornelia Huck { 39985ab69981SCornelia Huck struct klist_iter i; 39995ab69981SCornelia Huck struct device *child; 40005ab69981SCornelia Huck 40015ab69981SCornelia Huck if (!parent) 40025ab69981SCornelia Huck return NULL; 40035ab69981SCornelia Huck 4004f791b8c8SGreg Kroah-Hartman klist_iter_init(&parent->p->klist_children, &i); 40055ab69981SCornelia Huck while ((child = next_device(&i))) 40065ab69981SCornelia Huck if (match(child, data) && get_device(child)) 40075ab69981SCornelia Huck break; 40085ab69981SCornelia Huck klist_iter_exit(&i); 40095ab69981SCornelia Huck return child; 40105ab69981SCornelia Huck } 401186df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_find_child); 40125ab69981SCornelia Huck 4013dad9bb01SHeikki Krogerus /** 4014dad9bb01SHeikki Krogerus * device_find_child_by_name - device iterator for locating a child device. 4015dad9bb01SHeikki Krogerus * @parent: parent struct device 4016dad9bb01SHeikki Krogerus * @name: name of the child device 4017dad9bb01SHeikki Krogerus * 4018dad9bb01SHeikki Krogerus * This is similar to the device_find_child() function above, but it 4019dad9bb01SHeikki Krogerus * returns a reference to a device that has the name @name. 4020dad9bb01SHeikki Krogerus * 4021dad9bb01SHeikki Krogerus * NOTE: you will need to drop the reference with put_device() after use. 4022dad9bb01SHeikki Krogerus */ 4023dad9bb01SHeikki Krogerus struct device *device_find_child_by_name(struct device *parent, 4024dad9bb01SHeikki Krogerus const char *name) 4025dad9bb01SHeikki Krogerus { 4026dad9bb01SHeikki Krogerus struct klist_iter i; 4027dad9bb01SHeikki Krogerus struct device *child; 4028dad9bb01SHeikki Krogerus 4029dad9bb01SHeikki Krogerus if (!parent) 4030dad9bb01SHeikki Krogerus return NULL; 4031dad9bb01SHeikki Krogerus 4032dad9bb01SHeikki Krogerus klist_iter_init(&parent->p->klist_children, &i); 4033dad9bb01SHeikki Krogerus while ((child = next_device(&i))) 4034c77f520dSDan Williams if (sysfs_streq(dev_name(child), name) && get_device(child)) 4035dad9bb01SHeikki Krogerus break; 4036dad9bb01SHeikki Krogerus klist_iter_exit(&i); 4037dad9bb01SHeikki Krogerus return child; 4038dad9bb01SHeikki Krogerus } 4039dad9bb01SHeikki Krogerus EXPORT_SYMBOL_GPL(device_find_child_by_name); 4040dad9bb01SHeikki Krogerus 404182b070beSAndy Shevchenko static int match_any(struct device *dev, void *unused) 404282b070beSAndy Shevchenko { 404382b070beSAndy Shevchenko return 1; 404482b070beSAndy Shevchenko } 404582b070beSAndy Shevchenko 404682b070beSAndy Shevchenko /** 404782b070beSAndy Shevchenko * device_find_any_child - device iterator for locating a child device, if any. 404882b070beSAndy Shevchenko * @parent: parent struct device 404982b070beSAndy Shevchenko * 405082b070beSAndy Shevchenko * This is similar to the device_find_child() function above, but it 405182b070beSAndy Shevchenko * returns a reference to a child device, if any. 405282b070beSAndy Shevchenko * 405382b070beSAndy Shevchenko * NOTE: you will need to drop the reference with put_device() after use. 405482b070beSAndy Shevchenko */ 405582b070beSAndy Shevchenko struct device *device_find_any_child(struct device *parent) 405682b070beSAndy Shevchenko { 405782b070beSAndy Shevchenko return device_find_child(parent, NULL, match_any); 405882b070beSAndy Shevchenko } 405982b070beSAndy Shevchenko EXPORT_SYMBOL_GPL(device_find_any_child); 406082b070beSAndy Shevchenko 40611da177e4SLinus Torvalds int __init devices_init(void) 40621da177e4SLinus Torvalds { 4063881c6cfdSGreg Kroah-Hartman devices_kset = kset_create_and_add("devices", &device_uevent_ops, NULL); 4064881c6cfdSGreg Kroah-Hartman if (!devices_kset) 4065881c6cfdSGreg Kroah-Hartman return -ENOMEM; 4066e105b8bfSDan Williams dev_kobj = kobject_create_and_add("dev", NULL); 4067e105b8bfSDan Williams if (!dev_kobj) 4068e105b8bfSDan Williams goto dev_kobj_err; 4069e105b8bfSDan Williams sysfs_dev_block_kobj = kobject_create_and_add("block", dev_kobj); 4070e105b8bfSDan Williams if (!sysfs_dev_block_kobj) 4071e105b8bfSDan Williams goto block_kobj_err; 4072e105b8bfSDan Williams sysfs_dev_char_kobj = kobject_create_and_add("char", dev_kobj); 4073e105b8bfSDan Williams if (!sysfs_dev_char_kobj) 4074e105b8bfSDan Williams goto char_kobj_err; 4075e105b8bfSDan Williams 4076881c6cfdSGreg Kroah-Hartman return 0; 4077e105b8bfSDan Williams 4078e105b8bfSDan Williams char_kobj_err: 4079e105b8bfSDan Williams kobject_put(sysfs_dev_block_kobj); 4080e105b8bfSDan Williams block_kobj_err: 4081e105b8bfSDan Williams kobject_put(dev_kobj); 4082e105b8bfSDan Williams dev_kobj_err: 4083e105b8bfSDan Williams kset_unregister(devices_kset); 4084e105b8bfSDan Williams return -ENOMEM; 40851da177e4SLinus Torvalds } 40861da177e4SLinus Torvalds 40874f3549d7SRafael J. Wysocki static int device_check_offline(struct device *dev, void *not_used) 40884f3549d7SRafael J. Wysocki { 40894f3549d7SRafael J. Wysocki int ret; 40904f3549d7SRafael J. Wysocki 40914f3549d7SRafael J. Wysocki ret = device_for_each_child(dev, NULL, device_check_offline); 40924f3549d7SRafael J. Wysocki if (ret) 40934f3549d7SRafael J. Wysocki return ret; 40944f3549d7SRafael J. Wysocki 40954f3549d7SRafael J. Wysocki return device_supports_offline(dev) && !dev->offline ? -EBUSY : 0; 40964f3549d7SRafael J. Wysocki } 40974f3549d7SRafael J. Wysocki 40984f3549d7SRafael J. Wysocki /** 40994f3549d7SRafael J. Wysocki * device_offline - Prepare the device for hot-removal. 41004f3549d7SRafael J. Wysocki * @dev: Device to be put offline. 41014f3549d7SRafael J. Wysocki * 41024f3549d7SRafael J. Wysocki * Execute the device bus type's .offline() callback, if present, to prepare 41034f3549d7SRafael J. Wysocki * the device for a subsequent hot-removal. If that succeeds, the device must 41044f3549d7SRafael J. Wysocki * not be used until either it is removed or its bus type's .online() callback 41054f3549d7SRafael J. Wysocki * is executed. 41064f3549d7SRafael J. Wysocki * 41074f3549d7SRafael J. Wysocki * Call under device_hotplug_lock. 41084f3549d7SRafael J. Wysocki */ 41094f3549d7SRafael J. Wysocki int device_offline(struct device *dev) 41104f3549d7SRafael J. Wysocki { 41114f3549d7SRafael J. Wysocki int ret; 41124f3549d7SRafael J. Wysocki 41134f3549d7SRafael J. Wysocki if (dev->offline_disabled) 41144f3549d7SRafael J. Wysocki return -EPERM; 41154f3549d7SRafael J. Wysocki 41164f3549d7SRafael J. Wysocki ret = device_for_each_child(dev, NULL, device_check_offline); 41174f3549d7SRafael J. Wysocki if (ret) 41184f3549d7SRafael J. Wysocki return ret; 41194f3549d7SRafael J. Wysocki 41204f3549d7SRafael J. Wysocki device_lock(dev); 41214f3549d7SRafael J. Wysocki if (device_supports_offline(dev)) { 41224f3549d7SRafael J. Wysocki if (dev->offline) { 41234f3549d7SRafael J. Wysocki ret = 1; 41244f3549d7SRafael J. Wysocki } else { 41254f3549d7SRafael J. Wysocki ret = dev->bus->offline(dev); 41264f3549d7SRafael J. Wysocki if (!ret) { 41274f3549d7SRafael J. Wysocki kobject_uevent(&dev->kobj, KOBJ_OFFLINE); 41284f3549d7SRafael J. Wysocki dev->offline = true; 41294f3549d7SRafael J. Wysocki } 41304f3549d7SRafael J. Wysocki } 41314f3549d7SRafael J. Wysocki } 41324f3549d7SRafael J. Wysocki device_unlock(dev); 41334f3549d7SRafael J. Wysocki 41344f3549d7SRafael J. Wysocki return ret; 41354f3549d7SRafael J. Wysocki } 41364f3549d7SRafael J. Wysocki 41374f3549d7SRafael J. Wysocki /** 41384f3549d7SRafael J. Wysocki * device_online - Put the device back online after successful device_offline(). 41394f3549d7SRafael J. Wysocki * @dev: Device to be put back online. 41404f3549d7SRafael J. Wysocki * 41414f3549d7SRafael J. Wysocki * If device_offline() has been successfully executed for @dev, but the device 41424f3549d7SRafael J. Wysocki * has not been removed subsequently, execute its bus type's .online() callback 41434f3549d7SRafael J. Wysocki * to indicate that the device can be used again. 41444f3549d7SRafael J. Wysocki * 41454f3549d7SRafael J. Wysocki * Call under device_hotplug_lock. 41464f3549d7SRafael J. Wysocki */ 41474f3549d7SRafael J. Wysocki int device_online(struct device *dev) 41484f3549d7SRafael J. Wysocki { 41494f3549d7SRafael J. Wysocki int ret = 0; 41504f3549d7SRafael J. Wysocki 41514f3549d7SRafael J. Wysocki device_lock(dev); 41524f3549d7SRafael J. Wysocki if (device_supports_offline(dev)) { 41534f3549d7SRafael J. Wysocki if (dev->offline) { 41544f3549d7SRafael J. Wysocki ret = dev->bus->online(dev); 41554f3549d7SRafael J. Wysocki if (!ret) { 41564f3549d7SRafael J. Wysocki kobject_uevent(&dev->kobj, KOBJ_ONLINE); 41574f3549d7SRafael J. Wysocki dev->offline = false; 41584f3549d7SRafael J. Wysocki } 41594f3549d7SRafael J. Wysocki } else { 41604f3549d7SRafael J. Wysocki ret = 1; 41614f3549d7SRafael J. Wysocki } 41624f3549d7SRafael J. Wysocki } 41634f3549d7SRafael J. Wysocki device_unlock(dev); 41644f3549d7SRafael J. Wysocki 41654f3549d7SRafael J. Wysocki return ret; 41664f3549d7SRafael J. Wysocki } 41674f3549d7SRafael J. Wysocki 41687f100d15SKarthigan Srinivasan struct root_device { 41690aa0dc41SMark McLoughlin struct device dev; 41700aa0dc41SMark McLoughlin struct module *owner; 41710aa0dc41SMark McLoughlin }; 41720aa0dc41SMark McLoughlin 417393058424SJosh Triplett static inline struct root_device *to_root_device(struct device *d) 4174481e2079SFerenc Wagner { 4175481e2079SFerenc Wagner return container_of(d, struct root_device, dev); 4176481e2079SFerenc Wagner } 41770aa0dc41SMark McLoughlin 41780aa0dc41SMark McLoughlin static void root_device_release(struct device *dev) 41790aa0dc41SMark McLoughlin { 41800aa0dc41SMark McLoughlin kfree(to_root_device(dev)); 41810aa0dc41SMark McLoughlin } 41820aa0dc41SMark McLoughlin 41830aa0dc41SMark McLoughlin /** 41840aa0dc41SMark McLoughlin * __root_device_register - allocate and register a root device 41850aa0dc41SMark McLoughlin * @name: root device name 41860aa0dc41SMark McLoughlin * @owner: owner module of the root device, usually THIS_MODULE 41870aa0dc41SMark McLoughlin * 41880aa0dc41SMark McLoughlin * This function allocates a root device and registers it 41890aa0dc41SMark McLoughlin * using device_register(). In order to free the returned 41900aa0dc41SMark McLoughlin * device, use root_device_unregister(). 41910aa0dc41SMark McLoughlin * 41920aa0dc41SMark McLoughlin * Root devices are dummy devices which allow other devices 41930aa0dc41SMark McLoughlin * to be grouped under /sys/devices. Use this function to 41940aa0dc41SMark McLoughlin * allocate a root device and then use it as the parent of 41950aa0dc41SMark McLoughlin * any device which should appear under /sys/devices/{name} 41960aa0dc41SMark McLoughlin * 41970aa0dc41SMark McLoughlin * The /sys/devices/{name} directory will also contain a 41980aa0dc41SMark McLoughlin * 'module' symlink which points to the @owner directory 41990aa0dc41SMark McLoughlin * in sysfs. 42000aa0dc41SMark McLoughlin * 4201f0eae0edSJani Nikula * Returns &struct device pointer on success, or ERR_PTR() on error. 4202f0eae0edSJani Nikula * 42030aa0dc41SMark McLoughlin * Note: You probably want to use root_device_register(). 42040aa0dc41SMark McLoughlin */ 42050aa0dc41SMark McLoughlin struct device *__root_device_register(const char *name, struct module *owner) 42060aa0dc41SMark McLoughlin { 42070aa0dc41SMark McLoughlin struct root_device *root; 42080aa0dc41SMark McLoughlin int err = -ENOMEM; 42090aa0dc41SMark McLoughlin 42100aa0dc41SMark McLoughlin root = kzalloc(sizeof(struct root_device), GFP_KERNEL); 42110aa0dc41SMark McLoughlin if (!root) 42120aa0dc41SMark McLoughlin return ERR_PTR(err); 42130aa0dc41SMark McLoughlin 4214acc0e90fSGreg Kroah-Hartman err = dev_set_name(&root->dev, "%s", name); 42150aa0dc41SMark McLoughlin if (err) { 42160aa0dc41SMark McLoughlin kfree(root); 42170aa0dc41SMark McLoughlin return ERR_PTR(err); 42180aa0dc41SMark McLoughlin } 42190aa0dc41SMark McLoughlin 42200aa0dc41SMark McLoughlin root->dev.release = root_device_release; 42210aa0dc41SMark McLoughlin 42220aa0dc41SMark McLoughlin err = device_register(&root->dev); 42230aa0dc41SMark McLoughlin if (err) { 42240aa0dc41SMark McLoughlin put_device(&root->dev); 42250aa0dc41SMark McLoughlin return ERR_PTR(err); 42260aa0dc41SMark McLoughlin } 42270aa0dc41SMark McLoughlin 42281d9e882bSChristoph Egger #ifdef CONFIG_MODULES /* gotta find a "cleaner" way to do this */ 42290aa0dc41SMark McLoughlin if (owner) { 42300aa0dc41SMark McLoughlin struct module_kobject *mk = &owner->mkobj; 42310aa0dc41SMark McLoughlin 42320aa0dc41SMark McLoughlin err = sysfs_create_link(&root->dev.kobj, &mk->kobj, "module"); 42330aa0dc41SMark McLoughlin if (err) { 42340aa0dc41SMark McLoughlin device_unregister(&root->dev); 42350aa0dc41SMark McLoughlin return ERR_PTR(err); 42360aa0dc41SMark McLoughlin } 42370aa0dc41SMark McLoughlin root->owner = owner; 42380aa0dc41SMark McLoughlin } 42390aa0dc41SMark McLoughlin #endif 42400aa0dc41SMark McLoughlin 42410aa0dc41SMark McLoughlin return &root->dev; 42420aa0dc41SMark McLoughlin } 42430aa0dc41SMark McLoughlin EXPORT_SYMBOL_GPL(__root_device_register); 42440aa0dc41SMark McLoughlin 42450aa0dc41SMark McLoughlin /** 42460aa0dc41SMark McLoughlin * root_device_unregister - unregister and free a root device 42477cbcf225SRandy Dunlap * @dev: device going away 42480aa0dc41SMark McLoughlin * 42490aa0dc41SMark McLoughlin * This function unregisters and cleans up a device that was created by 42500aa0dc41SMark McLoughlin * root_device_register(). 42510aa0dc41SMark McLoughlin */ 42520aa0dc41SMark McLoughlin void root_device_unregister(struct device *dev) 42530aa0dc41SMark McLoughlin { 42540aa0dc41SMark McLoughlin struct root_device *root = to_root_device(dev); 42550aa0dc41SMark McLoughlin 42560aa0dc41SMark McLoughlin if (root->owner) 42570aa0dc41SMark McLoughlin sysfs_remove_link(&root->dev.kobj, "module"); 42580aa0dc41SMark McLoughlin 42590aa0dc41SMark McLoughlin device_unregister(dev); 42600aa0dc41SMark McLoughlin } 42610aa0dc41SMark McLoughlin EXPORT_SYMBOL_GPL(root_device_unregister); 42620aa0dc41SMark McLoughlin 426323681e47SGreg Kroah-Hartman 426423681e47SGreg Kroah-Hartman static void device_create_release(struct device *dev) 426523681e47SGreg Kroah-Hartman { 42661e0b2cf9SKay Sievers pr_debug("device: '%s': %s\n", dev_name(dev), __func__); 426723681e47SGreg Kroah-Hartman kfree(dev); 426823681e47SGreg Kroah-Hartman } 426923681e47SGreg Kroah-Hartman 42706a8b55d7SMathieu Malaterre static __printf(6, 0) struct device * 42712bd5c639SGreg Kroah-Hartman device_create_groups_vargs(const struct class *class, struct device *parent, 427239ef3112SGuenter Roeck dev_t devt, void *drvdata, 427339ef3112SGuenter Roeck const struct attribute_group **groups, 427439ef3112SGuenter Roeck const char *fmt, va_list args) 427539ef3112SGuenter Roeck { 427639ef3112SGuenter Roeck struct device *dev = NULL; 427739ef3112SGuenter Roeck int retval = -ENODEV; 427839ef3112SGuenter Roeck 4279d70590d5SYang Yingliang if (IS_ERR_OR_NULL(class)) 428039ef3112SGuenter Roeck goto error; 428139ef3112SGuenter Roeck 428239ef3112SGuenter Roeck dev = kzalloc(sizeof(*dev), GFP_KERNEL); 428339ef3112SGuenter Roeck if (!dev) { 428439ef3112SGuenter Roeck retval = -ENOMEM; 428539ef3112SGuenter Roeck goto error; 428639ef3112SGuenter Roeck } 428739ef3112SGuenter Roeck 4288bbc780f8SDavid Herrmann device_initialize(dev); 428939ef3112SGuenter Roeck dev->devt = devt; 429039ef3112SGuenter Roeck dev->class = class; 429139ef3112SGuenter Roeck dev->parent = parent; 429239ef3112SGuenter Roeck dev->groups = groups; 429339ef3112SGuenter Roeck dev->release = device_create_release; 429439ef3112SGuenter Roeck dev_set_drvdata(dev, drvdata); 429539ef3112SGuenter Roeck 429639ef3112SGuenter Roeck retval = kobject_set_name_vargs(&dev->kobj, fmt, args); 429739ef3112SGuenter Roeck if (retval) 429839ef3112SGuenter Roeck goto error; 429939ef3112SGuenter Roeck 4300bbc780f8SDavid Herrmann retval = device_add(dev); 430139ef3112SGuenter Roeck if (retval) 430239ef3112SGuenter Roeck goto error; 430339ef3112SGuenter Roeck 430439ef3112SGuenter Roeck return dev; 430539ef3112SGuenter Roeck 430639ef3112SGuenter Roeck error: 430739ef3112SGuenter Roeck put_device(dev); 430839ef3112SGuenter Roeck return ERR_PTR(retval); 430939ef3112SGuenter Roeck } 431039ef3112SGuenter Roeck 431123681e47SGreg Kroah-Hartman /** 43124e106739SGreg Kroah-Hartman * device_create - creates a device and registers it with sysfs 43138882b394SGreg Kroah-Hartman * @class: pointer to the struct class that this device should be registered to 43148882b394SGreg Kroah-Hartman * @parent: pointer to the parent struct device of this new device, if any 43158882b394SGreg Kroah-Hartman * @devt: the dev_t for the char device to be added 43168882b394SGreg Kroah-Hartman * @drvdata: the data to be added to the device for callbacks 43178882b394SGreg Kroah-Hartman * @fmt: string for the device's name 43188882b394SGreg Kroah-Hartman * 43198882b394SGreg Kroah-Hartman * This function can be used by char device classes. A struct device 43208882b394SGreg Kroah-Hartman * will be created in sysfs, registered to the specified class. 43218882b394SGreg Kroah-Hartman * 43228882b394SGreg Kroah-Hartman * A "dev" file will be created, showing the dev_t for the device, if 43238882b394SGreg Kroah-Hartman * the dev_t is not 0,0. 43248882b394SGreg Kroah-Hartman * If a pointer to a parent struct device is passed in, the newly created 43258882b394SGreg Kroah-Hartman * struct device will be a child of that device in sysfs. 43268882b394SGreg Kroah-Hartman * The pointer to the struct device will be returned from the call. 43278882b394SGreg Kroah-Hartman * Any further sysfs files that might be required can be created using this 43288882b394SGreg Kroah-Hartman * pointer. 43298882b394SGreg Kroah-Hartman * 4330f0eae0edSJani Nikula * Returns &struct device pointer on success, or ERR_PTR() on error. 4331f0eae0edSJani Nikula * 43328882b394SGreg Kroah-Hartman * Note: the struct class passed to this function must have previously 43338882b394SGreg Kroah-Hartman * been created with a call to class_create(). 43348882b394SGreg Kroah-Hartman */ 43352bd5c639SGreg Kroah-Hartman struct device *device_create(const struct class *class, struct device *parent, 43364e106739SGreg Kroah-Hartman dev_t devt, void *drvdata, const char *fmt, ...) 43378882b394SGreg Kroah-Hartman { 43388882b394SGreg Kroah-Hartman va_list vargs; 43398882b394SGreg Kroah-Hartman struct device *dev; 43408882b394SGreg Kroah-Hartman 43418882b394SGreg Kroah-Hartman va_start(vargs, fmt); 43424c747466SChristoph Hellwig dev = device_create_groups_vargs(class, parent, devt, drvdata, NULL, 43434c747466SChristoph Hellwig fmt, vargs); 43448882b394SGreg Kroah-Hartman va_end(vargs); 43458882b394SGreg Kroah-Hartman return dev; 43468882b394SGreg Kroah-Hartman } 43474e106739SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(device_create); 43488882b394SGreg Kroah-Hartman 434939ef3112SGuenter Roeck /** 435039ef3112SGuenter Roeck * device_create_with_groups - creates a device and registers it with sysfs 435139ef3112SGuenter Roeck * @class: pointer to the struct class that this device should be registered to 435239ef3112SGuenter Roeck * @parent: pointer to the parent struct device of this new device, if any 435339ef3112SGuenter Roeck * @devt: the dev_t for the char device to be added 435439ef3112SGuenter Roeck * @drvdata: the data to be added to the device for callbacks 435539ef3112SGuenter Roeck * @groups: NULL-terminated list of attribute groups to be created 435639ef3112SGuenter Roeck * @fmt: string for the device's name 435739ef3112SGuenter Roeck * 435839ef3112SGuenter Roeck * This function can be used by char device classes. A struct device 435939ef3112SGuenter Roeck * will be created in sysfs, registered to the specified class. 436039ef3112SGuenter Roeck * Additional attributes specified in the groups parameter will also 436139ef3112SGuenter Roeck * be created automatically. 436239ef3112SGuenter Roeck * 436339ef3112SGuenter Roeck * A "dev" file will be created, showing the dev_t for the device, if 436439ef3112SGuenter Roeck * the dev_t is not 0,0. 436539ef3112SGuenter Roeck * If a pointer to a parent struct device is passed in, the newly created 436639ef3112SGuenter Roeck * struct device will be a child of that device in sysfs. 436739ef3112SGuenter Roeck * The pointer to the struct device will be returned from the call. 436839ef3112SGuenter Roeck * Any further sysfs files that might be required can be created using this 436939ef3112SGuenter Roeck * pointer. 437039ef3112SGuenter Roeck * 437139ef3112SGuenter Roeck * Returns &struct device pointer on success, or ERR_PTR() on error. 437239ef3112SGuenter Roeck * 437339ef3112SGuenter Roeck * Note: the struct class passed to this function must have previously 437439ef3112SGuenter Roeck * been created with a call to class_create(). 437539ef3112SGuenter Roeck */ 43762bd5c639SGreg Kroah-Hartman struct device *device_create_with_groups(const struct class *class, 437739ef3112SGuenter Roeck struct device *parent, dev_t devt, 437839ef3112SGuenter Roeck void *drvdata, 437939ef3112SGuenter Roeck const struct attribute_group **groups, 438039ef3112SGuenter Roeck const char *fmt, ...) 438139ef3112SGuenter Roeck { 438239ef3112SGuenter Roeck va_list vargs; 438339ef3112SGuenter Roeck struct device *dev; 438439ef3112SGuenter Roeck 438539ef3112SGuenter Roeck va_start(vargs, fmt); 438639ef3112SGuenter Roeck dev = device_create_groups_vargs(class, parent, devt, drvdata, groups, 438739ef3112SGuenter Roeck fmt, vargs); 438839ef3112SGuenter Roeck va_end(vargs); 438939ef3112SGuenter Roeck return dev; 439039ef3112SGuenter Roeck } 439139ef3112SGuenter Roeck EXPORT_SYMBOL_GPL(device_create_with_groups); 439239ef3112SGuenter Roeck 4393775b64d2SRafael J. Wysocki /** 4394775b64d2SRafael J. Wysocki * device_destroy - removes a device that was created with device_create() 4395775b64d2SRafael J. Wysocki * @class: pointer to the struct class that this device was registered with 4396775b64d2SRafael J. Wysocki * @devt: the dev_t of the device that was previously registered 4397775b64d2SRafael J. Wysocki * 4398775b64d2SRafael J. Wysocki * This call unregisters and cleans up a device that was created with a 4399775b64d2SRafael J. Wysocki * call to device_create(). 4400775b64d2SRafael J. Wysocki */ 4401d2fff096SGreg Kroah-Hartman void device_destroy(const struct class *class, dev_t devt) 4402775b64d2SRafael J. Wysocki { 4403775b64d2SRafael J. Wysocki struct device *dev; 4404775b64d2SRafael J. Wysocki 44054495dfddSSuzuki K Poulose dev = class_find_device_by_devt(class, devt); 4406cd35449bSDave Young if (dev) { 4407cd35449bSDave Young put_device(dev); 440823681e47SGreg Kroah-Hartman device_unregister(dev); 440923681e47SGreg Kroah-Hartman } 4410cd35449bSDave Young } 441123681e47SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(device_destroy); 4412a2de48caSGreg Kroah-Hartman 4413a2de48caSGreg Kroah-Hartman /** 4414a2de48caSGreg Kroah-Hartman * device_rename - renames a device 4415a2de48caSGreg Kroah-Hartman * @dev: the pointer to the struct device to be renamed 4416a2de48caSGreg Kroah-Hartman * @new_name: the new name of the device 4417030c1d2bSEric W. Biederman * 4418030c1d2bSEric W. Biederman * It is the responsibility of the caller to provide mutual 4419030c1d2bSEric W. Biederman * exclusion between two different calls of device_rename 4420030c1d2bSEric W. Biederman * on the same device to ensure that new_name is valid and 4421030c1d2bSEric W. Biederman * won't conflict with other devices. 4422c6c0ac66SMichael Ellerman * 4423a5462516STimur Tabi * Note: Don't call this function. Currently, the networking layer calls this 4424a5462516STimur Tabi * function, but that will change. The following text from Kay Sievers offers 4425a5462516STimur Tabi * some insight: 4426a5462516STimur Tabi * 4427a5462516STimur Tabi * Renaming devices is racy at many levels, symlinks and other stuff are not 4428a5462516STimur Tabi * replaced atomically, and you get a "move" uevent, but it's not easy to 4429a5462516STimur Tabi * connect the event to the old and new device. Device nodes are not renamed at 4430a5462516STimur Tabi * all, there isn't even support for that in the kernel now. 4431a5462516STimur Tabi * 4432a5462516STimur Tabi * In the meantime, during renaming, your target name might be taken by another 4433a5462516STimur Tabi * driver, creating conflicts. Or the old name is taken directly after you 4434a5462516STimur Tabi * renamed it -- then you get events for the same DEVPATH, before you even see 4435a5462516STimur Tabi * the "move" event. It's just a mess, and nothing new should ever rely on 4436a5462516STimur Tabi * kernel device renaming. Besides that, it's not even implemented now for 4437a5462516STimur Tabi * other things than (driver-core wise very simple) network devices. 4438a5462516STimur Tabi * 4439a5462516STimur Tabi * We are currently about to change network renaming in udev to completely 4440a5462516STimur Tabi * disallow renaming of devices in the same namespace as the kernel uses, 4441a5462516STimur Tabi * because we can't solve the problems properly, that arise with swapping names 4442a5462516STimur Tabi * of multiple interfaces without races. Means, renaming of eth[0-9]* will only 4443a5462516STimur Tabi * be allowed to some other name than eth[0-9]*, for the aforementioned 4444a5462516STimur Tabi * reasons. 4445a5462516STimur Tabi * 4446a5462516STimur Tabi * Make up a "real" name in the driver before you register anything, or add 4447a5462516STimur Tabi * some other attributes for userspace to find the device, or use udev to add 4448a5462516STimur Tabi * symlinks -- but never rename kernel devices later, it's a complete mess. We 4449a5462516STimur Tabi * don't even want to get into that and try to implement the missing pieces in 4450a5462516STimur Tabi * the core. We really have other pieces to fix in the driver core mess. :) 4451a2de48caSGreg Kroah-Hartman */ 44526937e8f8SJohannes Berg int device_rename(struct device *dev, const char *new_name) 4453a2de48caSGreg Kroah-Hartman { 44544b30ee58STejun Heo struct kobject *kobj = &dev->kobj; 44552ee97cafSCornelia Huck char *old_device_name = NULL; 4456a2de48caSGreg Kroah-Hartman int error; 4457a2de48caSGreg Kroah-Hartman 4458a2de48caSGreg Kroah-Hartman dev = get_device(dev); 4459a2de48caSGreg Kroah-Hartman if (!dev) 4460a2de48caSGreg Kroah-Hartman return -EINVAL; 4461a2de48caSGreg Kroah-Hartman 446269df7533Sethan.zhao dev_dbg(dev, "renaming to %s\n", new_name); 4463a2de48caSGreg Kroah-Hartman 44641fa5ae85SKay Sievers old_device_name = kstrdup(dev_name(dev), GFP_KERNEL); 44652ee97cafSCornelia Huck if (!old_device_name) { 4466952ab431SJesper Juhl error = -ENOMEM; 44672ee97cafSCornelia Huck goto out; 4468952ab431SJesper Juhl } 4469a2de48caSGreg Kroah-Hartman 4470f349cf34SEric W. Biederman if (dev->class) { 44717d90e81aSGreg Kroah-Hartman struct subsys_private *sp = class_to_subsys(dev->class); 44727d90e81aSGreg Kroah-Hartman 44737d90e81aSGreg Kroah-Hartman if (!sp) { 44747d90e81aSGreg Kroah-Hartman error = -EINVAL; 44757d90e81aSGreg Kroah-Hartman goto out; 44767d90e81aSGreg Kroah-Hartman } 44777d90e81aSGreg Kroah-Hartman 44787d90e81aSGreg Kroah-Hartman error = sysfs_rename_link_ns(&sp->subsys.kobj, kobj, old_device_name, 44794b30ee58STejun Heo new_name, kobject_namespace(kobj)); 44807d90e81aSGreg Kroah-Hartman subsys_put(sp); 4481f349cf34SEric W. Biederman if (error) 4482f349cf34SEric W. Biederman goto out; 4483f349cf34SEric W. Biederman } 448439aba963SKay Sievers 44854b30ee58STejun Heo error = kobject_rename(kobj, new_name); 44861fa5ae85SKay Sievers if (error) 44872ee97cafSCornelia Huck goto out; 4488a2de48caSGreg Kroah-Hartman 44892ee97cafSCornelia Huck out: 4490a2de48caSGreg Kroah-Hartman put_device(dev); 4491a2de48caSGreg Kroah-Hartman 44922ee97cafSCornelia Huck kfree(old_device_name); 4493a2de48caSGreg Kroah-Hartman 4494a2de48caSGreg Kroah-Hartman return error; 4495a2de48caSGreg Kroah-Hartman } 4496a2807dbcSJohannes Berg EXPORT_SYMBOL_GPL(device_rename); 44978a82472fSCornelia Huck 44988a82472fSCornelia Huck static int device_move_class_links(struct device *dev, 44998a82472fSCornelia Huck struct device *old_parent, 45008a82472fSCornelia Huck struct device *new_parent) 45018a82472fSCornelia Huck { 4502f7f3461dSGreg Kroah-Hartman int error = 0; 45038a82472fSCornelia Huck 4504f7f3461dSGreg Kroah-Hartman if (old_parent) 4505f7f3461dSGreg Kroah-Hartman sysfs_remove_link(&dev->kobj, "device"); 4506f7f3461dSGreg Kroah-Hartman if (new_parent) 4507f7f3461dSGreg Kroah-Hartman error = sysfs_create_link(&dev->kobj, &new_parent->kobj, 4508f7f3461dSGreg Kroah-Hartman "device"); 4509f7f3461dSGreg Kroah-Hartman return error; 45108a82472fSCornelia Huck } 45118a82472fSCornelia Huck 45128a82472fSCornelia Huck /** 45138a82472fSCornelia Huck * device_move - moves a device to a new parent 45148a82472fSCornelia Huck * @dev: the pointer to the struct device to be moved 451513509860SWolfram Sang * @new_parent: the new parent of the device (can be NULL) 4516ffa6a705SCornelia Huck * @dpm_order: how to reorder the dpm_list 45178a82472fSCornelia Huck */ 4518ffa6a705SCornelia Huck int device_move(struct device *dev, struct device *new_parent, 4519ffa6a705SCornelia Huck enum dpm_order dpm_order) 45208a82472fSCornelia Huck { 45218a82472fSCornelia Huck int error; 45228a82472fSCornelia Huck struct device *old_parent; 4523c744aeaeSCornelia Huck struct kobject *new_parent_kobj; 45248a82472fSCornelia Huck 45258a82472fSCornelia Huck dev = get_device(dev); 45268a82472fSCornelia Huck if (!dev) 45278a82472fSCornelia Huck return -EINVAL; 45288a82472fSCornelia Huck 4529ffa6a705SCornelia Huck device_pm_lock(); 45308a82472fSCornelia Huck new_parent = get_device(new_parent); 4531c744aeaeSCornelia Huck new_parent_kobj = get_device_parent(dev, new_parent); 453284d0c27dSTetsuo Handa if (IS_ERR(new_parent_kobj)) { 453384d0c27dSTetsuo Handa error = PTR_ERR(new_parent_kobj); 453484d0c27dSTetsuo Handa put_device(new_parent); 453584d0c27dSTetsuo Handa goto out; 453684d0c27dSTetsuo Handa } 453763b6971aSCornelia Huck 45381e0b2cf9SKay Sievers pr_debug("device: '%s': %s: moving to '%s'\n", dev_name(dev), 45391e0b2cf9SKay Sievers __func__, new_parent ? dev_name(new_parent) : "<NULL>"); 4540c744aeaeSCornelia Huck error = kobject_move(&dev->kobj, new_parent_kobj); 45418a82472fSCornelia Huck if (error) { 454263b6971aSCornelia Huck cleanup_glue_dir(dev, new_parent_kobj); 45438a82472fSCornelia Huck put_device(new_parent); 45448a82472fSCornelia Huck goto out; 45458a82472fSCornelia Huck } 45468a82472fSCornelia Huck old_parent = dev->parent; 45478a82472fSCornelia Huck dev->parent = new_parent; 45488a82472fSCornelia Huck if (old_parent) 4549f791b8c8SGreg Kroah-Hartman klist_remove(&dev->p->knode_parent); 45500d358f22SYinghai Lu if (new_parent) { 4551f791b8c8SGreg Kroah-Hartman klist_add_tail(&dev->p->knode_parent, 4552f791b8c8SGreg Kroah-Hartman &new_parent->p->klist_children); 45530d358f22SYinghai Lu set_dev_node(dev, dev_to_node(new_parent)); 45540d358f22SYinghai Lu } 45550d358f22SYinghai Lu 4556bdd4034dSRabin Vincent if (dev->class) { 45578a82472fSCornelia Huck error = device_move_class_links(dev, old_parent, new_parent); 45588a82472fSCornelia Huck if (error) { 45598a82472fSCornelia Huck /* We ignore errors on cleanup since we're hosed anyway... */ 45608a82472fSCornelia Huck device_move_class_links(dev, new_parent, old_parent); 45618a82472fSCornelia Huck if (!kobject_move(&dev->kobj, &old_parent->kobj)) { 4562c744aeaeSCornelia Huck if (new_parent) 4563f791b8c8SGreg Kroah-Hartman klist_remove(&dev->p->knode_parent); 45640d358f22SYinghai Lu dev->parent = old_parent; 45650d358f22SYinghai Lu if (old_parent) { 4566f791b8c8SGreg Kroah-Hartman klist_add_tail(&dev->p->knode_parent, 4567f791b8c8SGreg Kroah-Hartman &old_parent->p->klist_children); 45680d358f22SYinghai Lu set_dev_node(dev, dev_to_node(old_parent)); 45690d358f22SYinghai Lu } 45708a82472fSCornelia Huck } 457163b6971aSCornelia Huck cleanup_glue_dir(dev, new_parent_kobj); 45728a82472fSCornelia Huck put_device(new_parent); 45738a82472fSCornelia Huck goto out; 45748a82472fSCornelia Huck } 4575bdd4034dSRabin Vincent } 4576ffa6a705SCornelia Huck switch (dpm_order) { 4577ffa6a705SCornelia Huck case DPM_ORDER_NONE: 4578ffa6a705SCornelia Huck break; 4579ffa6a705SCornelia Huck case DPM_ORDER_DEV_AFTER_PARENT: 4580ffa6a705SCornelia Huck device_pm_move_after(dev, new_parent); 458152cdbdd4SGrygorii Strashko devices_kset_move_after(dev, new_parent); 4582ffa6a705SCornelia Huck break; 4583ffa6a705SCornelia Huck case DPM_ORDER_PARENT_BEFORE_DEV: 4584ffa6a705SCornelia Huck device_pm_move_before(new_parent, dev); 458552cdbdd4SGrygorii Strashko devices_kset_move_before(new_parent, dev); 4586ffa6a705SCornelia Huck break; 4587ffa6a705SCornelia Huck case DPM_ORDER_DEV_LAST: 4588ffa6a705SCornelia Huck device_pm_move_last(dev); 458952cdbdd4SGrygorii Strashko devices_kset_move_last(dev); 4590ffa6a705SCornelia Huck break; 4591ffa6a705SCornelia Huck } 4592bdd4034dSRabin Vincent 45938a82472fSCornelia Huck put_device(old_parent); 45948a82472fSCornelia Huck out: 4595ffa6a705SCornelia Huck device_pm_unlock(); 45968a82472fSCornelia Huck put_device(dev); 45978a82472fSCornelia Huck return error; 45988a82472fSCornelia Huck } 45998a82472fSCornelia Huck EXPORT_SYMBOL_GPL(device_move); 460037b0c020SGreg Kroah-Hartman 4601b8f33e5dSChristian Brauner static int device_attrs_change_owner(struct device *dev, kuid_t kuid, 4602b8f33e5dSChristian Brauner kgid_t kgid) 4603b8f33e5dSChristian Brauner { 4604b8f33e5dSChristian Brauner struct kobject *kobj = &dev->kobj; 46059fa120fbSGreg Kroah-Hartman const struct class *class = dev->class; 4606b8f33e5dSChristian Brauner const struct device_type *type = dev->type; 4607b8f33e5dSChristian Brauner int error; 4608b8f33e5dSChristian Brauner 4609b8f33e5dSChristian Brauner if (class) { 4610b8f33e5dSChristian Brauner /* 4611b8f33e5dSChristian Brauner * Change the device groups of the device class for @dev to 4612b8f33e5dSChristian Brauner * @kuid/@kgid. 4613b8f33e5dSChristian Brauner */ 4614b8f33e5dSChristian Brauner error = sysfs_groups_change_owner(kobj, class->dev_groups, kuid, 4615b8f33e5dSChristian Brauner kgid); 4616b8f33e5dSChristian Brauner if (error) 4617b8f33e5dSChristian Brauner return error; 4618b8f33e5dSChristian Brauner } 4619b8f33e5dSChristian Brauner 4620b8f33e5dSChristian Brauner if (type) { 4621b8f33e5dSChristian Brauner /* 4622b8f33e5dSChristian Brauner * Change the device groups of the device type for @dev to 4623b8f33e5dSChristian Brauner * @kuid/@kgid. 4624b8f33e5dSChristian Brauner */ 4625b8f33e5dSChristian Brauner error = sysfs_groups_change_owner(kobj, type->groups, kuid, 4626b8f33e5dSChristian Brauner kgid); 4627b8f33e5dSChristian Brauner if (error) 4628b8f33e5dSChristian Brauner return error; 4629b8f33e5dSChristian Brauner } 4630b8f33e5dSChristian Brauner 4631b8f33e5dSChristian Brauner /* Change the device groups of @dev to @kuid/@kgid. */ 4632b8f33e5dSChristian Brauner error = sysfs_groups_change_owner(kobj, dev->groups, kuid, kgid); 4633b8f33e5dSChristian Brauner if (error) 4634b8f33e5dSChristian Brauner return error; 4635b8f33e5dSChristian Brauner 4636b8f33e5dSChristian Brauner if (device_supports_offline(dev) && !dev->offline_disabled) { 4637b8f33e5dSChristian Brauner /* Change online device attributes of @dev to @kuid/@kgid. */ 4638b8f33e5dSChristian Brauner error = sysfs_file_change_owner(kobj, dev_attr_online.attr.name, 4639b8f33e5dSChristian Brauner kuid, kgid); 4640b8f33e5dSChristian Brauner if (error) 4641b8f33e5dSChristian Brauner return error; 4642b8f33e5dSChristian Brauner } 4643b8f33e5dSChristian Brauner 4644b8f33e5dSChristian Brauner return 0; 4645b8f33e5dSChristian Brauner } 4646b8f33e5dSChristian Brauner 4647b8f33e5dSChristian Brauner /** 4648b8f33e5dSChristian Brauner * device_change_owner - change the owner of an existing device. 4649b8f33e5dSChristian Brauner * @dev: device. 4650b8f33e5dSChristian Brauner * @kuid: new owner's kuid 4651b8f33e5dSChristian Brauner * @kgid: new owner's kgid 4652b8f33e5dSChristian Brauner * 4653b8f33e5dSChristian Brauner * This changes the owner of @dev and its corresponding sysfs entries to 4654b8f33e5dSChristian Brauner * @kuid/@kgid. This function closely mirrors how @dev was added via driver 4655b8f33e5dSChristian Brauner * core. 4656b8f33e5dSChristian Brauner * 4657b8f33e5dSChristian Brauner * Returns 0 on success or error code on failure. 4658b8f33e5dSChristian Brauner */ 4659b8f33e5dSChristian Brauner int device_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid) 4660b8f33e5dSChristian Brauner { 4661b8f33e5dSChristian Brauner int error; 4662b8f33e5dSChristian Brauner struct kobject *kobj = &dev->kobj; 46637d90e81aSGreg Kroah-Hartman struct subsys_private *sp; 4664b8f33e5dSChristian Brauner 4665b8f33e5dSChristian Brauner dev = get_device(dev); 4666b8f33e5dSChristian Brauner if (!dev) 4667b8f33e5dSChristian Brauner return -EINVAL; 4668b8f33e5dSChristian Brauner 4669b8f33e5dSChristian Brauner /* 4670b8f33e5dSChristian Brauner * Change the kobject and the default attributes and groups of the 4671b8f33e5dSChristian Brauner * ktype associated with it to @kuid/@kgid. 4672b8f33e5dSChristian Brauner */ 4673b8f33e5dSChristian Brauner error = sysfs_change_owner(kobj, kuid, kgid); 4674b8f33e5dSChristian Brauner if (error) 4675b8f33e5dSChristian Brauner goto out; 4676b8f33e5dSChristian Brauner 4677b8f33e5dSChristian Brauner /* 4678b8f33e5dSChristian Brauner * Change the uevent file for @dev to the new owner. The uevent file 4679b8f33e5dSChristian Brauner * was created in a separate step when @dev got added and we mirror 4680b8f33e5dSChristian Brauner * that step here. 4681b8f33e5dSChristian Brauner */ 4682b8f33e5dSChristian Brauner error = sysfs_file_change_owner(kobj, dev_attr_uevent.attr.name, kuid, 4683b8f33e5dSChristian Brauner kgid); 4684b8f33e5dSChristian Brauner if (error) 4685b8f33e5dSChristian Brauner goto out; 4686b8f33e5dSChristian Brauner 4687b8f33e5dSChristian Brauner /* 4688b8f33e5dSChristian Brauner * Change the device groups, the device groups associated with the 4689b8f33e5dSChristian Brauner * device class, and the groups associated with the device type of @dev 4690b8f33e5dSChristian Brauner * to @kuid/@kgid. 4691b8f33e5dSChristian Brauner */ 4692b8f33e5dSChristian Brauner error = device_attrs_change_owner(dev, kuid, kgid); 4693b8f33e5dSChristian Brauner if (error) 4694b8f33e5dSChristian Brauner goto out; 4695b8f33e5dSChristian Brauner 46963b52fc5dSChristian Brauner error = dpm_sysfs_change_owner(dev, kuid, kgid); 46973b52fc5dSChristian Brauner if (error) 46983b52fc5dSChristian Brauner goto out; 46993b52fc5dSChristian Brauner 4700b8f33e5dSChristian Brauner /* 4701b8f33e5dSChristian Brauner * Change the owner of the symlink located in the class directory of 4702b8f33e5dSChristian Brauner * the device class associated with @dev which points to the actual 4703b8f33e5dSChristian Brauner * directory entry for @dev to @kuid/@kgid. This ensures that the 4704b8f33e5dSChristian Brauner * symlink shows the same permissions as its target. 4705b8f33e5dSChristian Brauner */ 47067d90e81aSGreg Kroah-Hartman sp = class_to_subsys(dev->class); 47077d90e81aSGreg Kroah-Hartman if (!sp) { 47087d90e81aSGreg Kroah-Hartman error = -EINVAL; 4709b8f33e5dSChristian Brauner goto out; 47107d90e81aSGreg Kroah-Hartman } 47117d90e81aSGreg Kroah-Hartman error = sysfs_link_change_owner(&sp->subsys.kobj, &dev->kobj, dev_name(dev), kuid, kgid); 47127d90e81aSGreg Kroah-Hartman subsys_put(sp); 4713b8f33e5dSChristian Brauner 4714b8f33e5dSChristian Brauner out: 4715b8f33e5dSChristian Brauner put_device(dev); 4716b8f33e5dSChristian Brauner return error; 4717b8f33e5dSChristian Brauner } 4718b8f33e5dSChristian Brauner EXPORT_SYMBOL_GPL(device_change_owner); 4719b8f33e5dSChristian Brauner 472037b0c020SGreg Kroah-Hartman /** 472137b0c020SGreg Kroah-Hartman * device_shutdown - call ->shutdown() on each device to shutdown. 472237b0c020SGreg Kroah-Hartman */ 472337b0c020SGreg Kroah-Hartman void device_shutdown(void) 472437b0c020SGreg Kroah-Hartman { 4725f123db8eSBenson Leung struct device *dev, *parent; 472637b0c020SGreg Kroah-Hartman 47273297c8fcSPingfan Liu wait_for_device_probe(); 47283297c8fcSPingfan Liu device_block_probing(); 47293297c8fcSPingfan Liu 473065650b35SRafael J. Wysocki cpufreq_suspend(); 473165650b35SRafael J. Wysocki 47326245838fSHugh Daschbach spin_lock(&devices_kset->list_lock); 47336245838fSHugh Daschbach /* 47346245838fSHugh Daschbach * Walk the devices list backward, shutting down each in turn. 47356245838fSHugh Daschbach * Beware that device unplug events may also start pulling 47366245838fSHugh Daschbach * devices offline, even as the system is shutting down. 47376245838fSHugh Daschbach */ 47386245838fSHugh Daschbach while (!list_empty(&devices_kset->list)) { 47396245838fSHugh Daschbach dev = list_entry(devices_kset->list.prev, struct device, 47406245838fSHugh Daschbach kobj.entry); 4741d1c6c030SMing Lei 4742d1c6c030SMing Lei /* 4743d1c6c030SMing Lei * hold reference count of device's parent to 4744d1c6c030SMing Lei * prevent it from being freed because parent's 4745d1c6c030SMing Lei * lock is to be held 4746d1c6c030SMing Lei */ 4747f123db8eSBenson Leung parent = get_device(dev->parent); 47486245838fSHugh Daschbach get_device(dev); 47496245838fSHugh Daschbach /* 47506245838fSHugh Daschbach * Make sure the device is off the kset list, in the 47516245838fSHugh Daschbach * event that dev->*->shutdown() doesn't remove it. 47526245838fSHugh Daschbach */ 47536245838fSHugh Daschbach list_del_init(&dev->kobj.entry); 47546245838fSHugh Daschbach spin_unlock(&devices_kset->list_lock); 4755fe6b91f4SAlan Stern 4756d1c6c030SMing Lei /* hold lock to avoid race with probe/release */ 4757f123db8eSBenson Leung if (parent) 4758f123db8eSBenson Leung device_lock(parent); 4759d1c6c030SMing Lei device_lock(dev); 4760d1c6c030SMing Lei 4761fe6b91f4SAlan Stern /* Don't allow any more runtime suspends */ 4762fe6b91f4SAlan Stern pm_runtime_get_noresume(dev); 4763fe6b91f4SAlan Stern pm_runtime_barrier(dev); 47646245838fSHugh Daschbach 47657521621eSMichal Suchanek if (dev->class && dev->class->shutdown_pre) { 4766f77af151SJosh Zimmerman if (initcall_debug) 47677521621eSMichal Suchanek dev_info(dev, "shutdown_pre\n"); 47687521621eSMichal Suchanek dev->class->shutdown_pre(dev); 47697521621eSMichal Suchanek } 47707521621eSMichal Suchanek if (dev->bus && dev->bus->shutdown) { 47710246c4faSShuoX Liu if (initcall_debug) 47720246c4faSShuoX Liu dev_info(dev, "shutdown\n"); 477337b0c020SGreg Kroah-Hartman dev->bus->shutdown(dev); 477437b0c020SGreg Kroah-Hartman } else if (dev->driver && dev->driver->shutdown) { 47750246c4faSShuoX Liu if (initcall_debug) 47760246c4faSShuoX Liu dev_info(dev, "shutdown\n"); 477737b0c020SGreg Kroah-Hartman dev->driver->shutdown(dev); 477837b0c020SGreg Kroah-Hartman } 4779d1c6c030SMing Lei 4780d1c6c030SMing Lei device_unlock(dev); 4781f123db8eSBenson Leung if (parent) 4782f123db8eSBenson Leung device_unlock(parent); 4783d1c6c030SMing Lei 47846245838fSHugh Daschbach put_device(dev); 4785f123db8eSBenson Leung put_device(parent); 47866245838fSHugh Daschbach 47876245838fSHugh Daschbach spin_lock(&devices_kset->list_lock); 478837b0c020SGreg Kroah-Hartman } 47896245838fSHugh Daschbach spin_unlock(&devices_kset->list_lock); 479037b0c020SGreg Kroah-Hartman } 479199bcf217SJoe Perches 479299bcf217SJoe Perches /* 479399bcf217SJoe Perches * Device logging functions 479499bcf217SJoe Perches */ 479599bcf217SJoe Perches 479699bcf217SJoe Perches #ifdef CONFIG_PRINTK 479774caba7fSJohn Ogness static void 479874caba7fSJohn Ogness set_dev_info(const struct device *dev, struct dev_printk_info *dev_info) 479999bcf217SJoe Perches { 4800c4e00daaSKay Sievers const char *subsys; 480174caba7fSJohn Ogness 480274caba7fSJohn Ogness memset(dev_info, 0, sizeof(*dev_info)); 480399bcf217SJoe Perches 4804c4e00daaSKay Sievers if (dev->class) 4805c4e00daaSKay Sievers subsys = dev->class->name; 4806c4e00daaSKay Sievers else if (dev->bus) 4807c4e00daaSKay Sievers subsys = dev->bus->name; 4808c4e00daaSKay Sievers else 480974caba7fSJohn Ogness return; 4810c4e00daaSKay Sievers 481174caba7fSJohn Ogness strscpy(dev_info->subsystem, subsys, sizeof(dev_info->subsystem)); 4812c4e00daaSKay Sievers 4813c4e00daaSKay Sievers /* 4814c4e00daaSKay Sievers * Add device identifier DEVICE=: 4815c4e00daaSKay Sievers * b12:8 block dev_t 4816c4e00daaSKay Sievers * c127:3 char dev_t 4817c4e00daaSKay Sievers * n8 netdev ifindex 4818c4e00daaSKay Sievers * +sound:card0 subsystem:devname 4819c4e00daaSKay Sievers */ 4820c4e00daaSKay Sievers if (MAJOR(dev->devt)) { 4821c4e00daaSKay Sievers char c; 4822c4e00daaSKay Sievers 4823c4e00daaSKay Sievers if (strcmp(subsys, "block") == 0) 4824c4e00daaSKay Sievers c = 'b'; 4825c4e00daaSKay Sievers else 4826c4e00daaSKay Sievers c = 'c'; 482774caba7fSJohn Ogness 482874caba7fSJohn Ogness snprintf(dev_info->device, sizeof(dev_info->device), 482974caba7fSJohn Ogness "%c%u:%u", c, MAJOR(dev->devt), MINOR(dev->devt)); 4830c4e00daaSKay Sievers } else if (strcmp(subsys, "net") == 0) { 4831c4e00daaSKay Sievers struct net_device *net = to_net_dev(dev); 4832c4e00daaSKay Sievers 483374caba7fSJohn Ogness snprintf(dev_info->device, sizeof(dev_info->device), 483474caba7fSJohn Ogness "n%u", net->ifindex); 4835c4e00daaSKay Sievers } else { 483674caba7fSJohn Ogness snprintf(dev_info->device, sizeof(dev_info->device), 483774caba7fSJohn Ogness "+%s:%s", subsys, dev_name(dev)); 4838c4e00daaSKay Sievers } 483999bcf217SJoe Perches } 4840798efc60SJoe Perches 484105e4e5b8SJoe Perches int dev_vprintk_emit(int level, const struct device *dev, 484205e4e5b8SJoe Perches const char *fmt, va_list args) 484305e4e5b8SJoe Perches { 484474caba7fSJohn Ogness struct dev_printk_info dev_info; 484505e4e5b8SJoe Perches 484674caba7fSJohn Ogness set_dev_info(dev, &dev_info); 484705e4e5b8SJoe Perches 484874caba7fSJohn Ogness return vprintk_emit(0, level, &dev_info, fmt, args); 484905e4e5b8SJoe Perches } 485005e4e5b8SJoe Perches EXPORT_SYMBOL(dev_vprintk_emit); 485105e4e5b8SJoe Perches 485205e4e5b8SJoe Perches int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...) 485305e4e5b8SJoe Perches { 485405e4e5b8SJoe Perches va_list args; 485505e4e5b8SJoe Perches int r; 485605e4e5b8SJoe Perches 485705e4e5b8SJoe Perches va_start(args, fmt); 485805e4e5b8SJoe Perches 485905e4e5b8SJoe Perches r = dev_vprintk_emit(level, dev, fmt, args); 486005e4e5b8SJoe Perches 486105e4e5b8SJoe Perches va_end(args); 486205e4e5b8SJoe Perches 486305e4e5b8SJoe Perches return r; 486405e4e5b8SJoe Perches } 486505e4e5b8SJoe Perches EXPORT_SYMBOL(dev_printk_emit); 486605e4e5b8SJoe Perches 4867d1f1052cSJoe Perches static void __dev_printk(const char *level, const struct device *dev, 4868798efc60SJoe Perches struct va_format *vaf) 4869798efc60SJoe Perches { 4870d1f1052cSJoe Perches if (dev) 4871d1f1052cSJoe Perches dev_printk_emit(level[1] - '0', dev, "%s %s: %pV", 4872798efc60SJoe Perches dev_driver_string(dev), dev_name(dev), vaf); 4873d1f1052cSJoe Perches else 4874d1f1052cSJoe Perches printk("%s(NULL device *): %pV", level, vaf); 4875798efc60SJoe Perches } 487699bcf217SJoe Perches 4877ad7d61f1SChris Down void _dev_printk(const char *level, const struct device *dev, 487899bcf217SJoe Perches const char *fmt, ...) 487999bcf217SJoe Perches { 488099bcf217SJoe Perches struct va_format vaf; 488199bcf217SJoe Perches va_list args; 488299bcf217SJoe Perches 488399bcf217SJoe Perches va_start(args, fmt); 488499bcf217SJoe Perches 488599bcf217SJoe Perches vaf.fmt = fmt; 488699bcf217SJoe Perches vaf.va = &args; 488799bcf217SJoe Perches 4888d1f1052cSJoe Perches __dev_printk(level, dev, &vaf); 4889798efc60SJoe Perches 489099bcf217SJoe Perches va_end(args); 489199bcf217SJoe Perches } 4892ad7d61f1SChris Down EXPORT_SYMBOL(_dev_printk); 489399bcf217SJoe Perches 489499bcf217SJoe Perches #define define_dev_printk_level(func, kern_level) \ 4895d1f1052cSJoe Perches void func(const struct device *dev, const char *fmt, ...) \ 489699bcf217SJoe Perches { \ 489799bcf217SJoe Perches struct va_format vaf; \ 489899bcf217SJoe Perches va_list args; \ 489999bcf217SJoe Perches \ 490099bcf217SJoe Perches va_start(args, fmt); \ 490199bcf217SJoe Perches \ 490299bcf217SJoe Perches vaf.fmt = fmt; \ 490399bcf217SJoe Perches vaf.va = &args; \ 490499bcf217SJoe Perches \ 4905d1f1052cSJoe Perches __dev_printk(kern_level, dev, &vaf); \ 4906798efc60SJoe Perches \ 490799bcf217SJoe Perches va_end(args); \ 490899bcf217SJoe Perches } \ 490999bcf217SJoe Perches EXPORT_SYMBOL(func); 491099bcf217SJoe Perches 4911663336eeSJoe Perches define_dev_printk_level(_dev_emerg, KERN_EMERG); 4912663336eeSJoe Perches define_dev_printk_level(_dev_alert, KERN_ALERT); 4913663336eeSJoe Perches define_dev_printk_level(_dev_crit, KERN_CRIT); 4914663336eeSJoe Perches define_dev_printk_level(_dev_err, KERN_ERR); 4915663336eeSJoe Perches define_dev_printk_level(_dev_warn, KERN_WARNING); 4916663336eeSJoe Perches define_dev_printk_level(_dev_notice, KERN_NOTICE); 491799bcf217SJoe Perches define_dev_printk_level(_dev_info, KERN_INFO); 491899bcf217SJoe Perches 491999bcf217SJoe Perches #endif 492097badf87SRafael J. Wysocki 4921a787e540SAndrzej Hajda /** 4922a787e540SAndrzej Hajda * dev_err_probe - probe error check and log helper 4923a787e540SAndrzej Hajda * @dev: the pointer to the struct device 4924a787e540SAndrzej Hajda * @err: error value to test 4925a787e540SAndrzej Hajda * @fmt: printf-style format string 4926a787e540SAndrzej Hajda * @...: arguments as specified in the format string 4927a787e540SAndrzej Hajda * 4928a787e540SAndrzej Hajda * This helper implements common pattern present in probe functions for error 4929a787e540SAndrzej Hajda * checking: print debug or error message depending if the error value is 4930a787e540SAndrzej Hajda * -EPROBE_DEFER and propagate error upwards. 4931d090b70eSAndrzej Hajda * In case of -EPROBE_DEFER it sets also defer probe reason, which can be 4932d090b70eSAndrzej Hajda * checked later by reading devices_deferred debugfs attribute. 4933074b3aadSMauro Carvalho Chehab * It replaces code sequence:: 4934074b3aadSMauro Carvalho Chehab * 4935a787e540SAndrzej Hajda * if (err != -EPROBE_DEFER) 4936a787e540SAndrzej Hajda * dev_err(dev, ...); 4937a787e540SAndrzej Hajda * else 4938a787e540SAndrzej Hajda * dev_dbg(dev, ...); 4939a787e540SAndrzej Hajda * return err; 4940074b3aadSMauro Carvalho Chehab * 4941074b3aadSMauro Carvalho Chehab * with:: 4942074b3aadSMauro Carvalho Chehab * 4943a787e540SAndrzej Hajda * return dev_err_probe(dev, err, ...); 4944a787e540SAndrzej Hajda * 49457065f922SDouglas Anderson * Note that it is deemed acceptable to use this function for error 49467065f922SDouglas Anderson * prints during probe even if the @err is known to never be -EPROBE_DEFER. 49477065f922SDouglas Anderson * The benefit compared to a normal dev_err() is the standardized format 49487065f922SDouglas Anderson * of the error code and the fact that the error code is returned. 49497065f922SDouglas Anderson * 4950a787e540SAndrzej Hajda * Returns @err. 4951a787e540SAndrzej Hajda * 4952a787e540SAndrzej Hajda */ 4953a787e540SAndrzej Hajda int dev_err_probe(const struct device *dev, int err, const char *fmt, ...) 4954a787e540SAndrzej Hajda { 4955a787e540SAndrzej Hajda struct va_format vaf; 4956a787e540SAndrzej Hajda va_list args; 4957a787e540SAndrzej Hajda 4958a787e540SAndrzej Hajda va_start(args, fmt); 4959a787e540SAndrzej Hajda vaf.fmt = fmt; 4960a787e540SAndrzej Hajda vaf.va = &args; 4961a787e540SAndrzej Hajda 4962d090b70eSAndrzej Hajda if (err != -EPROBE_DEFER) { 4963693a8e93SMichał Mirosław dev_err(dev, "error %pe: %pV", ERR_PTR(err), &vaf); 4964d090b70eSAndrzej Hajda } else { 4965d090b70eSAndrzej Hajda device_set_deferred_probe_reason(dev, &vaf); 4966693a8e93SMichał Mirosław dev_dbg(dev, "error %pe: %pV", ERR_PTR(err), &vaf); 4967d090b70eSAndrzej Hajda } 4968a787e540SAndrzej Hajda 4969a787e540SAndrzej Hajda va_end(args); 4970a787e540SAndrzej Hajda 4971a787e540SAndrzej Hajda return err; 4972a787e540SAndrzej Hajda } 4973a787e540SAndrzej Hajda EXPORT_SYMBOL_GPL(dev_err_probe); 4974a787e540SAndrzej Hajda 497597badf87SRafael J. Wysocki static inline bool fwnode_is_primary(struct fwnode_handle *fwnode) 497697badf87SRafael J. Wysocki { 497797badf87SRafael J. Wysocki return fwnode && !IS_ERR(fwnode->secondary); 497897badf87SRafael J. Wysocki } 497997badf87SRafael J. Wysocki 498097badf87SRafael J. Wysocki /** 498197badf87SRafael J. Wysocki * set_primary_fwnode - Change the primary firmware node of a given device. 498297badf87SRafael J. Wysocki * @dev: Device to handle. 498397badf87SRafael J. Wysocki * @fwnode: New primary firmware node of the device. 498497badf87SRafael J. Wysocki * 498597badf87SRafael J. Wysocki * Set the device's firmware node pointer to @fwnode, but if a secondary 498697badf87SRafael J. Wysocki * firmware node of the device is present, preserve it. 49873f7bddafSBard Liao * 49883f7bddafSBard Liao * Valid fwnode cases are: 49893f7bddafSBard Liao * - primary --> secondary --> -ENODEV 49903f7bddafSBard Liao * - primary --> NULL 49913f7bddafSBard Liao * - secondary --> -ENODEV 49923f7bddafSBard Liao * - NULL 499397badf87SRafael J. Wysocki */ 499497badf87SRafael J. Wysocki void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode) 499597badf87SRafael J. Wysocki { 499699aed922SAndy Shevchenko struct device *parent = dev->parent; 499797badf87SRafael J. Wysocki struct fwnode_handle *fn = dev->fwnode; 499897badf87SRafael J. Wysocki 4999c15e1bddSHeikki Krogerus if (fwnode) { 500097badf87SRafael J. Wysocki if (fwnode_is_primary(fn)) 500197badf87SRafael J. Wysocki fn = fn->secondary; 500297badf87SRafael J. Wysocki 500355f89a8aSMika Westerberg if (fn) { 500455f89a8aSMika Westerberg WARN_ON(fwnode->secondary); 500597badf87SRafael J. Wysocki fwnode->secondary = fn; 500655f89a8aSMika Westerberg } 500797badf87SRafael J. Wysocki dev->fwnode = fwnode; 500897badf87SRafael J. Wysocki } else { 5009c15e1bddSHeikki Krogerus if (fwnode_is_primary(fn)) { 5010c15e1bddSHeikki Krogerus dev->fwnode = fn->secondary; 50112f9e87f5SAndy Shevchenko 50122f9e87f5SAndy Shevchenko /* Skip nullifying fn->secondary if the primary is shared */ 50132f9e87f5SAndy Shevchenko if (parent && fn == parent->fwnode) 50142f9e87f5SAndy Shevchenko return; 50152f9e87f5SAndy Shevchenko 50163f7bddafSBard Liao /* Set fn->secondary = NULL, so fn remains the primary fwnode */ 501747f44699SBard Liao fn->secondary = NULL; 5018c15e1bddSHeikki Krogerus } else { 5019c15e1bddSHeikki Krogerus dev->fwnode = NULL; 5020c15e1bddSHeikki Krogerus } 502197badf87SRafael J. Wysocki } 502297badf87SRafael J. Wysocki } 502397badf87SRafael J. Wysocki EXPORT_SYMBOL_GPL(set_primary_fwnode); 502497badf87SRafael J. Wysocki 502597badf87SRafael J. Wysocki /** 502697badf87SRafael J. Wysocki * set_secondary_fwnode - Change the secondary firmware node of a given device. 502797badf87SRafael J. Wysocki * @dev: Device to handle. 502897badf87SRafael J. Wysocki * @fwnode: New secondary firmware node of the device. 502997badf87SRafael J. Wysocki * 503097badf87SRafael J. Wysocki * If a primary firmware node of the device is present, set its secondary 503197badf87SRafael J. Wysocki * pointer to @fwnode. Otherwise, set the device's firmware node pointer to 503297badf87SRafael J. Wysocki * @fwnode. 503397badf87SRafael J. Wysocki */ 503497badf87SRafael J. Wysocki void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode) 503597badf87SRafael J. Wysocki { 503697badf87SRafael J. Wysocki if (fwnode) 503797badf87SRafael J. Wysocki fwnode->secondary = ERR_PTR(-ENODEV); 503897badf87SRafael J. Wysocki 503997badf87SRafael J. Wysocki if (fwnode_is_primary(dev->fwnode)) 504097badf87SRafael J. Wysocki dev->fwnode->secondary = fwnode; 504197badf87SRafael J. Wysocki else 504297badf87SRafael J. Wysocki dev->fwnode = fwnode; 504397badf87SRafael J. Wysocki } 504496489ae1SAndy Shevchenko EXPORT_SYMBOL_GPL(set_secondary_fwnode); 50454e75e1d7SJohan Hovold 50464e75e1d7SJohan Hovold /** 50474e75e1d7SJohan Hovold * device_set_of_node_from_dev - reuse device-tree node of another device 50484e75e1d7SJohan Hovold * @dev: device whose device-tree node is being set 50494e75e1d7SJohan Hovold * @dev2: device whose device-tree node is being reused 50504e75e1d7SJohan Hovold * 50514e75e1d7SJohan Hovold * Takes another reference to the new device-tree node after first dropping 50524e75e1d7SJohan Hovold * any reference held to the old node. 50534e75e1d7SJohan Hovold */ 50544e75e1d7SJohan Hovold void device_set_of_node_from_dev(struct device *dev, const struct device *dev2) 50554e75e1d7SJohan Hovold { 50564e75e1d7SJohan Hovold of_node_put(dev->of_node); 50574e75e1d7SJohan Hovold dev->of_node = of_node_get(dev2->of_node); 50584e75e1d7SJohan Hovold dev->of_node_reused = true; 50594e75e1d7SJohan Hovold } 50604e75e1d7SJohan Hovold EXPORT_SYMBOL_GPL(device_set_of_node_from_dev); 506165b66682SSuzuki K Poulose 506243e76d46SIoana Ciornei void device_set_node(struct device *dev, struct fwnode_handle *fwnode) 506343e76d46SIoana Ciornei { 506443e76d46SIoana Ciornei dev->fwnode = fwnode; 506543e76d46SIoana Ciornei dev->of_node = to_of_node(fwnode); 506643e76d46SIoana Ciornei } 506743e76d46SIoana Ciornei EXPORT_SYMBOL_GPL(device_set_node); 506843e76d46SIoana Ciornei 50696cda08a2SSuzuki K Poulose int device_match_name(struct device *dev, const void *name) 50706cda08a2SSuzuki K Poulose { 50716cda08a2SSuzuki K Poulose return sysfs_streq(dev_name(dev), name); 50726cda08a2SSuzuki K Poulose } 50736cda08a2SSuzuki K Poulose EXPORT_SYMBOL_GPL(device_match_name); 50746cda08a2SSuzuki K Poulose 507565b66682SSuzuki K Poulose int device_match_of_node(struct device *dev, const void *np) 507665b66682SSuzuki K Poulose { 507765b66682SSuzuki K Poulose return dev->of_node == np; 507865b66682SSuzuki K Poulose } 507965b66682SSuzuki K Poulose EXPORT_SYMBOL_GPL(device_match_of_node); 508067843bbaSSuzuki K Poulose 508167843bbaSSuzuki K Poulose int device_match_fwnode(struct device *dev, const void *fwnode) 508267843bbaSSuzuki K Poulose { 508367843bbaSSuzuki K Poulose return dev_fwnode(dev) == fwnode; 508467843bbaSSuzuki K Poulose } 508567843bbaSSuzuki K Poulose EXPORT_SYMBOL_GPL(device_match_fwnode); 50864495dfddSSuzuki K Poulose 50874495dfddSSuzuki K Poulose int device_match_devt(struct device *dev, const void *pdevt) 50884495dfddSSuzuki K Poulose { 50894495dfddSSuzuki K Poulose return dev->devt == *(dev_t *)pdevt; 50904495dfddSSuzuki K Poulose } 50914495dfddSSuzuki K Poulose EXPORT_SYMBOL_GPL(device_match_devt); 509200500147SSuzuki K Poulose 509300500147SSuzuki K Poulose int device_match_acpi_dev(struct device *dev, const void *adev) 509400500147SSuzuki K Poulose { 509500500147SSuzuki K Poulose return ACPI_COMPANION(dev) == adev; 509600500147SSuzuki K Poulose } 509700500147SSuzuki K Poulose EXPORT_SYMBOL(device_match_acpi_dev); 50986bf85ba9SSuzuki K Poulose 5099a164ff53SAndy Shevchenko int device_match_acpi_handle(struct device *dev, const void *handle) 5100a164ff53SAndy Shevchenko { 5101a164ff53SAndy Shevchenko return ACPI_HANDLE(dev) == handle; 5102a164ff53SAndy Shevchenko } 5103a164ff53SAndy Shevchenko EXPORT_SYMBOL(device_match_acpi_handle); 5104a164ff53SAndy Shevchenko 51056bf85ba9SSuzuki K Poulose int device_match_any(struct device *dev, const void *unused) 51066bf85ba9SSuzuki K Poulose { 51076bf85ba9SSuzuki K Poulose return 1; 51086bf85ba9SSuzuki K Poulose } 51096bf85ba9SSuzuki K Poulose EXPORT_SYMBOL_GPL(device_match_any); 5110