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> 171da177e4SLinus Torvalds #include <linux/module.h> 181da177e4SLinus Torvalds #include <linux/slab.h> 191da177e4SLinus Torvalds #include <linux/string.h> 2023681e47SGreg Kroah-Hartman #include <linux/kdev_t.h> 21116af378SBenjamin Herrenschmidt #include <linux/notifier.h> 2207d57a32SGrant Likely #include <linux/of.h> 2307d57a32SGrant Likely #include <linux/of_device.h> 24da231fd5SKay Sievers #include <linux/genhd.h> 25f75b1c60SDave Young #include <linux/mutex.h> 26af8db150SPeter Chen #include <linux/pm_runtime.h> 27c4e00daaSKay Sievers #include <linux/netdevice.h> 28174cd4b1SIngo Molnar #include <linux/sched/signal.h> 2963967685SGreg Kroah-Hartman #include <linux/sysfs.h> 301da177e4SLinus Torvalds 311da177e4SLinus Torvalds #include "base.h" 321da177e4SLinus Torvalds #include "power/power.h" 331da177e4SLinus Torvalds 34e52eec13SAndi Kleen #ifdef CONFIG_SYSFS_DEPRECATED 35e52eec13SAndi Kleen #ifdef CONFIG_SYSFS_DEPRECATED_V2 36e52eec13SAndi Kleen long sysfs_deprecated = 1; 37e52eec13SAndi Kleen #else 38e52eec13SAndi Kleen long sysfs_deprecated = 0; 39e52eec13SAndi Kleen #endif 403454bf96SHanjun Guo static int __init sysfs_deprecated_setup(char *arg) 41e52eec13SAndi Kleen { 4234da5e67SJingoo Han return kstrtol(arg, 10, &sysfs_deprecated); 43e52eec13SAndi Kleen } 44e52eec13SAndi Kleen early_param("sysfs.deprecated", sysfs_deprecated_setup); 45e52eec13SAndi Kleen #endif 46e52eec13SAndi Kleen 479ed98953SRafael J. Wysocki /* Device links support. */ 48e2ae9bccSSaravana Kannan static LIST_HEAD(wait_for_suppliers); 49e2ae9bccSSaravana Kannan static DEFINE_MUTEX(wfs_lock); 50fc5a251dSSaravana Kannan static LIST_HEAD(deferred_sync); 51fc5a251dSSaravana Kannan static unsigned int defer_sync_state_count = 1; 529ed98953SRafael J. Wysocki 539ed98953SRafael J. Wysocki #ifdef CONFIG_SRCU 549ed98953SRafael J. Wysocki static DEFINE_MUTEX(device_links_lock); 559ed98953SRafael J. Wysocki DEFINE_STATIC_SRCU(device_links_srcu); 569ed98953SRafael J. Wysocki 579ed98953SRafael J. Wysocki static inline void device_links_write_lock(void) 589ed98953SRafael J. Wysocki { 599ed98953SRafael J. Wysocki mutex_lock(&device_links_lock); 609ed98953SRafael J. Wysocki } 619ed98953SRafael J. Wysocki 629ed98953SRafael J. Wysocki static inline void device_links_write_unlock(void) 639ed98953SRafael J. Wysocki { 649ed98953SRafael J. Wysocki mutex_unlock(&device_links_lock); 659ed98953SRafael J. Wysocki } 669ed98953SRafael J. Wysocki 679ed98953SRafael J. Wysocki int device_links_read_lock(void) 689ed98953SRafael J. Wysocki { 699ed98953SRafael J. Wysocki return srcu_read_lock(&device_links_srcu); 709ed98953SRafael J. Wysocki } 719ed98953SRafael J. Wysocki 729ed98953SRafael J. Wysocki void device_links_read_unlock(int idx) 739ed98953SRafael J. Wysocki { 749ed98953SRafael J. Wysocki srcu_read_unlock(&device_links_srcu, idx); 759ed98953SRafael J. Wysocki } 76c2fa1e1bSJoel Fernandes (Google) 77c2fa1e1bSJoel Fernandes (Google) int device_links_read_lock_held(void) 78c2fa1e1bSJoel Fernandes (Google) { 79c2fa1e1bSJoel Fernandes (Google) return srcu_read_lock_held(&device_links_srcu); 80c2fa1e1bSJoel Fernandes (Google) } 819ed98953SRafael J. Wysocki #else /* !CONFIG_SRCU */ 829ed98953SRafael J. Wysocki static DECLARE_RWSEM(device_links_lock); 839ed98953SRafael J. Wysocki 849ed98953SRafael J. Wysocki static inline void device_links_write_lock(void) 859ed98953SRafael J. Wysocki { 869ed98953SRafael J. Wysocki down_write(&device_links_lock); 879ed98953SRafael J. Wysocki } 889ed98953SRafael J. Wysocki 899ed98953SRafael J. Wysocki static inline void device_links_write_unlock(void) 909ed98953SRafael J. Wysocki { 919ed98953SRafael J. Wysocki up_write(&device_links_lock); 929ed98953SRafael J. Wysocki } 939ed98953SRafael J. Wysocki 949ed98953SRafael J. Wysocki int device_links_read_lock(void) 959ed98953SRafael J. Wysocki { 969ed98953SRafael J. Wysocki down_read(&device_links_lock); 979ed98953SRafael J. Wysocki return 0; 989ed98953SRafael J. Wysocki } 999ed98953SRafael J. Wysocki 1009ed98953SRafael J. Wysocki void device_links_read_unlock(int not_used) 1019ed98953SRafael J. Wysocki { 1029ed98953SRafael J. Wysocki up_read(&device_links_lock); 1039ed98953SRafael J. Wysocki } 104c2fa1e1bSJoel Fernandes (Google) 105c2fa1e1bSJoel Fernandes (Google) #ifdef CONFIG_DEBUG_LOCK_ALLOC 106c2fa1e1bSJoel Fernandes (Google) int device_links_read_lock_held(void) 107c2fa1e1bSJoel Fernandes (Google) { 108c2fa1e1bSJoel Fernandes (Google) return lockdep_is_held(&device_links_lock); 109c2fa1e1bSJoel Fernandes (Google) } 110c2fa1e1bSJoel Fernandes (Google) #endif 1119ed98953SRafael J. Wysocki #endif /* !CONFIG_SRCU */ 1129ed98953SRafael J. Wysocki 1139ed98953SRafael J. Wysocki /** 1149ed98953SRafael J. Wysocki * device_is_dependent - Check if one device depends on another one 1159ed98953SRafael J. Wysocki * @dev: Device to check dependencies for. 1169ed98953SRafael J. Wysocki * @target: Device to check against. 1179ed98953SRafael J. Wysocki * 1189ed98953SRafael J. Wysocki * Check if @target depends on @dev or any device dependent on it (its child or 1199ed98953SRafael J. Wysocki * its consumer etc). Return 1 if that is the case or 0 otherwise. 1209ed98953SRafael J. Wysocki */ 1219ed98953SRafael J. Wysocki static int device_is_dependent(struct device *dev, void *target) 1229ed98953SRafael J. Wysocki { 1239ed98953SRafael J. Wysocki struct device_link *link; 1249ed98953SRafael J. Wysocki int ret; 1259ed98953SRafael J. Wysocki 126e16f4f3eSBenjamin Gaignard if (dev == target) 1279ed98953SRafael J. Wysocki return 1; 1289ed98953SRafael J. Wysocki 1299ed98953SRafael J. Wysocki ret = device_for_each_child(dev, target, device_is_dependent); 1309ed98953SRafael J. Wysocki if (ret) 1319ed98953SRafael J. Wysocki return ret; 1329ed98953SRafael J. Wysocki 1339ed98953SRafael J. Wysocki list_for_each_entry(link, &dev->links.consumers, s_node) { 13405ef983eSSaravana Kannan if (link->flags == (DL_FLAG_SYNC_STATE_ONLY | DL_FLAG_MANAGED)) 13505ef983eSSaravana Kannan continue; 13605ef983eSSaravana Kannan 137e16f4f3eSBenjamin Gaignard if (link->consumer == target) 1389ed98953SRafael J. Wysocki return 1; 1399ed98953SRafael J. Wysocki 1409ed98953SRafael J. Wysocki ret = device_is_dependent(link->consumer, target); 1419ed98953SRafael J. Wysocki if (ret) 1429ed98953SRafael J. Wysocki break; 1439ed98953SRafael J. Wysocki } 1449ed98953SRafael J. Wysocki return ret; 1459ed98953SRafael J. Wysocki } 1469ed98953SRafael J. Wysocki 147515db266SRafael J. Wysocki static void device_link_init_status(struct device_link *link, 148515db266SRafael J. Wysocki struct device *consumer, 149515db266SRafael J. Wysocki struct device *supplier) 150515db266SRafael J. Wysocki { 151515db266SRafael J. Wysocki switch (supplier->links.status) { 152515db266SRafael J. Wysocki case DL_DEV_PROBING: 153515db266SRafael J. Wysocki switch (consumer->links.status) { 154515db266SRafael J. Wysocki case DL_DEV_PROBING: 155515db266SRafael J. Wysocki /* 156515db266SRafael J. Wysocki * A consumer driver can create a link to a supplier 157515db266SRafael J. Wysocki * that has not completed its probing yet as long as it 158515db266SRafael J. Wysocki * knows that the supplier is already functional (for 159515db266SRafael J. Wysocki * example, it has just acquired some resources from the 160515db266SRafael J. Wysocki * supplier). 161515db266SRafael J. Wysocki */ 162515db266SRafael J. Wysocki link->status = DL_STATE_CONSUMER_PROBE; 163515db266SRafael J. Wysocki break; 164515db266SRafael J. Wysocki default: 165515db266SRafael J. Wysocki link->status = DL_STATE_DORMANT; 166515db266SRafael J. Wysocki break; 167515db266SRafael J. Wysocki } 168515db266SRafael J. Wysocki break; 169515db266SRafael J. Wysocki case DL_DEV_DRIVER_BOUND: 170515db266SRafael J. Wysocki switch (consumer->links.status) { 171515db266SRafael J. Wysocki case DL_DEV_PROBING: 172515db266SRafael J. Wysocki link->status = DL_STATE_CONSUMER_PROBE; 173515db266SRafael J. Wysocki break; 174515db266SRafael J. Wysocki case DL_DEV_DRIVER_BOUND: 175515db266SRafael J. Wysocki link->status = DL_STATE_ACTIVE; 176515db266SRafael J. Wysocki break; 177515db266SRafael J. Wysocki default: 178515db266SRafael J. Wysocki link->status = DL_STATE_AVAILABLE; 179515db266SRafael J. Wysocki break; 180515db266SRafael J. Wysocki } 181515db266SRafael J. Wysocki break; 182515db266SRafael J. Wysocki case DL_DEV_UNBINDING: 183515db266SRafael J. Wysocki link->status = DL_STATE_SUPPLIER_UNBIND; 184515db266SRafael J. Wysocki break; 185515db266SRafael J. Wysocki default: 186515db266SRafael J. Wysocki link->status = DL_STATE_DORMANT; 187515db266SRafael J. Wysocki break; 188515db266SRafael J. Wysocki } 189515db266SRafael J. Wysocki } 190515db266SRafael J. Wysocki 1919ed98953SRafael J. Wysocki static int device_reorder_to_tail(struct device *dev, void *not_used) 1929ed98953SRafael J. Wysocki { 1939ed98953SRafael J. Wysocki struct device_link *link; 1949ed98953SRafael J. Wysocki 1959ed98953SRafael J. Wysocki /* 1969ed98953SRafael J. Wysocki * Devices that have not been registered yet will be put to the ends 1979ed98953SRafael J. Wysocki * of the lists during the registration, so skip them here. 1989ed98953SRafael J. Wysocki */ 1999ed98953SRafael J. Wysocki if (device_is_registered(dev)) 2009ed98953SRafael J. Wysocki devices_kset_move_last(dev); 2019ed98953SRafael J. Wysocki 2029ed98953SRafael J. Wysocki if (device_pm_initialized(dev)) 2039ed98953SRafael J. Wysocki device_pm_move_last(dev); 2049ed98953SRafael J. Wysocki 2059ed98953SRafael J. Wysocki device_for_each_child(dev, NULL, device_reorder_to_tail); 20605ef983eSSaravana Kannan list_for_each_entry(link, &dev->links.consumers, s_node) { 20705ef983eSSaravana Kannan if (link->flags == (DL_FLAG_SYNC_STATE_ONLY | DL_FLAG_MANAGED)) 20805ef983eSSaravana Kannan continue; 2099ed98953SRafael J. Wysocki device_reorder_to_tail(link->consumer, NULL); 21005ef983eSSaravana Kannan } 2119ed98953SRafael J. Wysocki 2129ed98953SRafael J. Wysocki return 0; 2139ed98953SRafael J. Wysocki } 2149ed98953SRafael J. Wysocki 2159ed98953SRafael J. Wysocki /** 216494fd7b7SFeng Kan * device_pm_move_to_tail - Move set of devices to the end of device lists 217494fd7b7SFeng Kan * @dev: Device to move 218494fd7b7SFeng Kan * 219494fd7b7SFeng Kan * This is a device_reorder_to_tail() wrapper taking the requisite locks. 220494fd7b7SFeng Kan * 221494fd7b7SFeng Kan * It moves the @dev along with all of its children and all of its consumers 222494fd7b7SFeng Kan * to the ends of the device_kset and dpm_list, recursively. 223494fd7b7SFeng Kan */ 224494fd7b7SFeng Kan void device_pm_move_to_tail(struct device *dev) 225494fd7b7SFeng Kan { 226494fd7b7SFeng Kan int idx; 227494fd7b7SFeng Kan 228494fd7b7SFeng Kan idx = device_links_read_lock(); 229494fd7b7SFeng Kan device_pm_lock(); 230494fd7b7SFeng Kan device_reorder_to_tail(dev, NULL); 231494fd7b7SFeng Kan device_pm_unlock(); 232494fd7b7SFeng Kan device_links_read_unlock(idx); 233494fd7b7SFeng Kan } 234494fd7b7SFeng Kan 235515db266SRafael J. Wysocki #define DL_MANAGED_LINK_FLAGS (DL_FLAG_AUTOREMOVE_CONSUMER | \ 236515db266SRafael J. Wysocki DL_FLAG_AUTOREMOVE_SUPPLIER | \ 23705ef983eSSaravana Kannan DL_FLAG_AUTOPROBE_CONSUMER | \ 23805ef983eSSaravana Kannan DL_FLAG_SYNC_STATE_ONLY) 239515db266SRafael J. Wysocki 240fb583c8eSRafael J. Wysocki #define DL_ADD_VALID_FLAGS (DL_MANAGED_LINK_FLAGS | DL_FLAG_STATELESS | \ 241fb583c8eSRafael J. Wysocki DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE) 242fb583c8eSRafael J. Wysocki 243494fd7b7SFeng Kan /** 2449ed98953SRafael J. Wysocki * device_link_add - Create a link between two devices. 2459ed98953SRafael J. Wysocki * @consumer: Consumer end of the link. 2469ed98953SRafael J. Wysocki * @supplier: Supplier end of the link. 2479ed98953SRafael J. Wysocki * @flags: Link flags. 2489ed98953SRafael J. Wysocki * 24921d5c57bSRafael J. Wysocki * The caller is responsible for the proper synchronization of the link creation 25021d5c57bSRafael J. Wysocki * with runtime PM. First, setting the DL_FLAG_PM_RUNTIME flag will cause the 25121d5c57bSRafael J. Wysocki * runtime PM framework to take the link into account. Second, if the 25221d5c57bSRafael J. Wysocki * DL_FLAG_RPM_ACTIVE flag is set in addition to it, the supplier devices will 25321d5c57bSRafael J. Wysocki * be forced into the active metastate and reference-counted upon the creation 25421d5c57bSRafael J. Wysocki * of the link. If DL_FLAG_PM_RUNTIME is not set, DL_FLAG_RPM_ACTIVE will be 25521d5c57bSRafael J. Wysocki * ignored. 25621d5c57bSRafael J. Wysocki * 257515db266SRafael J. Wysocki * If DL_FLAG_STATELESS is set in @flags, the caller of this function is 258515db266SRafael J. Wysocki * expected to release the link returned by it directly with the help of either 259515db266SRafael J. Wysocki * device_link_del() or device_link_remove(). 26072175d4eSRafael J. Wysocki * 26172175d4eSRafael J. Wysocki * If that flag is not set, however, the caller of this function is handing the 26272175d4eSRafael J. Wysocki * management of the link over to the driver core entirely and its return value 26372175d4eSRafael J. Wysocki * can only be used to check whether or not the link is present. In that case, 26472175d4eSRafael J. Wysocki * the DL_FLAG_AUTOREMOVE_CONSUMER and DL_FLAG_AUTOREMOVE_SUPPLIER device link 26572175d4eSRafael J. Wysocki * flags can be used to indicate to the driver core when the link can be safely 26672175d4eSRafael J. Wysocki * deleted. Namely, setting one of them in @flags indicates to the driver core 26772175d4eSRafael J. Wysocki * that the link is not going to be used (by the given caller of this function) 26872175d4eSRafael J. Wysocki * after unbinding the consumer or supplier driver, respectively, from its 26972175d4eSRafael J. Wysocki * device, so the link can be deleted at that point. If none of them is set, 27072175d4eSRafael J. Wysocki * the link will be maintained until one of the devices pointed to by it (either 27172175d4eSRafael J. Wysocki * the consumer or the supplier) is unregistered. 272c8d50986SRafael J. Wysocki * 273e7dd4010SRafael J. Wysocki * Also, if DL_FLAG_STATELESS, DL_FLAG_AUTOREMOVE_CONSUMER and 274e7dd4010SRafael J. Wysocki * DL_FLAG_AUTOREMOVE_SUPPLIER are not set in @flags (that is, a persistent 275e7dd4010SRafael J. Wysocki * managed device link is being added), the DL_FLAG_AUTOPROBE_CONSUMER flag can 276e7dd4010SRafael J. Wysocki * be used to request the driver core to automaticall probe for a consmer 277e7dd4010SRafael J. Wysocki * driver after successfully binding a driver to the supplier device. 278e7dd4010SRafael J. Wysocki * 279515db266SRafael J. Wysocki * The combination of DL_FLAG_STATELESS and one of DL_FLAG_AUTOREMOVE_CONSUMER, 280515db266SRafael J. Wysocki * DL_FLAG_AUTOREMOVE_SUPPLIER, or DL_FLAG_AUTOPROBE_CONSUMER set in @flags at 281515db266SRafael J. Wysocki * the same time is invalid and will cause NULL to be returned upfront. 282515db266SRafael J. Wysocki * However, if a device link between the given @consumer and @supplier pair 283515db266SRafael J. Wysocki * exists already when this function is called for them, the existing link will 284515db266SRafael J. Wysocki * be returned regardless of its current type and status (the link's flags may 285515db266SRafael J. Wysocki * be modified then). The caller of this function is then expected to treat 286515db266SRafael J. Wysocki * the link as though it has just been created, so (in particular) if 287515db266SRafael J. Wysocki * DL_FLAG_STATELESS was passed in @flags, the link needs to be released 288515db266SRafael J. Wysocki * explicitly when not needed any more (as stated above). 2899ed98953SRafael J. Wysocki * 2909ed98953SRafael J. Wysocki * A side effect of the link creation is re-ordering of dpm_list and the 2919ed98953SRafael J. Wysocki * devices_kset list by moving the consumer device and all devices depending 2929ed98953SRafael J. Wysocki * on it to the ends of these lists (that does not happen to devices that have 2939ed98953SRafael J. Wysocki * not been registered when this function is called). 2949ed98953SRafael J. Wysocki * 2959ed98953SRafael J. Wysocki * The supplier device is required to be registered when this function is called 2969ed98953SRafael J. Wysocki * and NULL will be returned if that is not the case. The consumer device need 29764df1148SLukas Wunner * not be registered, however. 2989ed98953SRafael J. Wysocki */ 2999ed98953SRafael J. Wysocki struct device_link *device_link_add(struct device *consumer, 3009ed98953SRafael J. Wysocki struct device *supplier, u32 flags) 3019ed98953SRafael J. Wysocki { 3029ed98953SRafael J. Wysocki struct device_link *link; 3039ed98953SRafael J. Wysocki 304fb583c8eSRafael J. Wysocki if (!consumer || !supplier || flags & ~DL_ADD_VALID_FLAGS || 305515db266SRafael J. Wysocki (flags & DL_FLAG_STATELESS && flags & DL_MANAGED_LINK_FLAGS) || 30605ef983eSSaravana Kannan (flags & DL_FLAG_SYNC_STATE_ONLY && 30705ef983eSSaravana Kannan flags != DL_FLAG_SYNC_STATE_ONLY) || 308e7dd4010SRafael J. Wysocki (flags & DL_FLAG_AUTOPROBE_CONSUMER && 309e7dd4010SRafael J. Wysocki flags & (DL_FLAG_AUTOREMOVE_CONSUMER | 310e7dd4010SRafael J. Wysocki DL_FLAG_AUTOREMOVE_SUPPLIER))) 3119ed98953SRafael J. Wysocki return NULL; 3129ed98953SRafael J. Wysocki 3135db25c9eSRafael J. Wysocki if (flags & DL_FLAG_PM_RUNTIME && flags & DL_FLAG_RPM_ACTIVE) { 3145db25c9eSRafael J. Wysocki if (pm_runtime_get_sync(supplier) < 0) { 3155db25c9eSRafael J. Wysocki pm_runtime_put_noidle(supplier); 3165db25c9eSRafael J. Wysocki return NULL; 3175db25c9eSRafael J. Wysocki } 3185db25c9eSRafael J. Wysocki } 3195db25c9eSRafael J. Wysocki 320515db266SRafael J. Wysocki if (!(flags & DL_FLAG_STATELESS)) 321515db266SRafael J. Wysocki flags |= DL_FLAG_MANAGED; 322515db266SRafael J. Wysocki 3239ed98953SRafael J. Wysocki device_links_write_lock(); 3249ed98953SRafael J. Wysocki device_pm_lock(); 3259ed98953SRafael J. Wysocki 3269ed98953SRafael J. Wysocki /* 3279ed98953SRafael J. Wysocki * If the supplier has not been fully registered yet or there is a 32805ef983eSSaravana Kannan * reverse (non-SYNC_STATE_ONLY) dependency between the consumer and 32905ef983eSSaravana Kannan * the supplier already in the graph, return NULL. If the link is a 33005ef983eSSaravana Kannan * SYNC_STATE_ONLY link, we don't check for reverse dependencies 33105ef983eSSaravana Kannan * because it only affects sync_state() callbacks. 3329ed98953SRafael J. Wysocki */ 3339ed98953SRafael J. Wysocki if (!device_pm_initialized(supplier) 33405ef983eSSaravana Kannan || (!(flags & DL_FLAG_SYNC_STATE_ONLY) && 33505ef983eSSaravana Kannan device_is_dependent(consumer, supplier))) { 3369ed98953SRafael J. Wysocki link = NULL; 3379ed98953SRafael J. Wysocki goto out; 3389ed98953SRafael J. Wysocki } 3399ed98953SRafael J. Wysocki 34072175d4eSRafael J. Wysocki /* 34172175d4eSRafael J. Wysocki * DL_FLAG_AUTOREMOVE_SUPPLIER indicates that the link will be needed 34272175d4eSRafael J. Wysocki * longer than for DL_FLAG_AUTOREMOVE_CONSUMER and setting them both 34372175d4eSRafael J. Wysocki * together doesn't make sense, so prefer DL_FLAG_AUTOREMOVE_SUPPLIER. 34472175d4eSRafael J. Wysocki */ 34572175d4eSRafael J. Wysocki if (flags & DL_FLAG_AUTOREMOVE_SUPPLIER) 34672175d4eSRafael J. Wysocki flags &= ~DL_FLAG_AUTOREMOVE_CONSUMER; 34772175d4eSRafael J. Wysocki 348f265df55SRafael J. Wysocki list_for_each_entry(link, &supplier->links.consumers, s_node) { 349f265df55SRafael J. Wysocki if (link->consumer != consumer) 350f265df55SRafael J. Wysocki continue; 351f265df55SRafael J. Wysocki 352e2f3cd83SRafael J. Wysocki if (flags & DL_FLAG_PM_RUNTIME) { 353e2f3cd83SRafael J. Wysocki if (!(link->flags & DL_FLAG_PM_RUNTIME)) { 3544c06c4e6SRafael J. Wysocki pm_runtime_new_link(consumer); 355e2f3cd83SRafael J. Wysocki link->flags |= DL_FLAG_PM_RUNTIME; 356e2f3cd83SRafael J. Wysocki } 357e2f3cd83SRafael J. Wysocki if (flags & DL_FLAG_RPM_ACTIVE) 35836003d4cSRafael J. Wysocki refcount_inc(&link->rpm_active); 359e2f3cd83SRafael J. Wysocki } 360e2f3cd83SRafael J. Wysocki 36172175d4eSRafael J. Wysocki if (flags & DL_FLAG_STATELESS) { 362ead18c23SLukas Wunner kref_get(&link->kref); 36305ef983eSSaravana Kannan if (link->flags & DL_FLAG_SYNC_STATE_ONLY && 36405ef983eSSaravana Kannan !(link->flags & DL_FLAG_STATELESS)) { 36505ef983eSSaravana Kannan link->flags |= DL_FLAG_STATELESS; 36605ef983eSSaravana Kannan goto reorder; 36705ef983eSSaravana Kannan } else { 3689ed98953SRafael J. Wysocki goto out; 369ead18c23SLukas Wunner } 37005ef983eSSaravana Kannan } 3719ed98953SRafael J. Wysocki 37272175d4eSRafael J. Wysocki /* 37372175d4eSRafael J. Wysocki * If the life time of the link following from the new flags is 37472175d4eSRafael J. Wysocki * longer than indicated by the flags of the existing link, 37572175d4eSRafael J. Wysocki * update the existing link to stay around longer. 37672175d4eSRafael J. Wysocki */ 37772175d4eSRafael J. Wysocki if (flags & DL_FLAG_AUTOREMOVE_SUPPLIER) { 37872175d4eSRafael J. Wysocki if (link->flags & DL_FLAG_AUTOREMOVE_CONSUMER) { 37972175d4eSRafael J. Wysocki link->flags &= ~DL_FLAG_AUTOREMOVE_CONSUMER; 38072175d4eSRafael J. Wysocki link->flags |= DL_FLAG_AUTOREMOVE_SUPPLIER; 38172175d4eSRafael J. Wysocki } 38272175d4eSRafael J. Wysocki } else if (!(flags & DL_FLAG_AUTOREMOVE_CONSUMER)) { 38372175d4eSRafael J. Wysocki link->flags &= ~(DL_FLAG_AUTOREMOVE_CONSUMER | 38472175d4eSRafael J. Wysocki DL_FLAG_AUTOREMOVE_SUPPLIER); 38572175d4eSRafael J. Wysocki } 386515db266SRafael J. Wysocki if (!(link->flags & DL_FLAG_MANAGED)) { 387515db266SRafael J. Wysocki kref_get(&link->kref); 388515db266SRafael J. Wysocki link->flags |= DL_FLAG_MANAGED; 389515db266SRafael J. Wysocki device_link_init_status(link, consumer, supplier); 390515db266SRafael J. Wysocki } 39105ef983eSSaravana Kannan if (link->flags & DL_FLAG_SYNC_STATE_ONLY && 39205ef983eSSaravana Kannan !(flags & DL_FLAG_SYNC_STATE_ONLY)) { 39305ef983eSSaravana Kannan link->flags &= ~DL_FLAG_SYNC_STATE_ONLY; 39405ef983eSSaravana Kannan goto reorder; 39505ef983eSSaravana Kannan } 39605ef983eSSaravana Kannan 39772175d4eSRafael J. Wysocki goto out; 39872175d4eSRafael J. Wysocki } 39972175d4eSRafael J. Wysocki 40021d5c57bSRafael J. Wysocki link = kzalloc(sizeof(*link), GFP_KERNEL); 4019ed98953SRafael J. Wysocki if (!link) 4029ed98953SRafael J. Wysocki goto out; 4039ed98953SRafael J. Wysocki 404e2f3cd83SRafael J. Wysocki refcount_set(&link->rpm_active, 1); 405e2f3cd83SRafael J. Wysocki 406baa8809fSRafael J. Wysocki if (flags & DL_FLAG_PM_RUNTIME) { 407e2f3cd83SRafael J. Wysocki if (flags & DL_FLAG_RPM_ACTIVE) 40836003d4cSRafael J. Wysocki refcount_inc(&link->rpm_active); 409e2f3cd83SRafael J. Wysocki 4104c06c4e6SRafael J. Wysocki pm_runtime_new_link(consumer); 41121d5c57bSRafael J. Wysocki } 412e2f3cd83SRafael J. Wysocki 4139ed98953SRafael J. Wysocki get_device(supplier); 4149ed98953SRafael J. Wysocki link->supplier = supplier; 4159ed98953SRafael J. Wysocki INIT_LIST_HEAD(&link->s_node); 4169ed98953SRafael J. Wysocki get_device(consumer); 4179ed98953SRafael J. Wysocki link->consumer = consumer; 4189ed98953SRafael J. Wysocki INIT_LIST_HEAD(&link->c_node); 4199ed98953SRafael J. Wysocki link->flags = flags; 420ead18c23SLukas Wunner kref_init(&link->kref); 4219ed98953SRafael J. Wysocki 42264df1148SLukas Wunner /* Determine the initial link state. */ 423515db266SRafael J. Wysocki if (flags & DL_FLAG_STATELESS) 4249ed98953SRafael J. Wysocki link->status = DL_STATE_NONE; 425515db266SRafael J. Wysocki else 426515db266SRafael J. Wysocki device_link_init_status(link, consumer, supplier); 4279ed98953SRafael J. Wysocki 4289ed98953SRafael J. Wysocki /* 42915cfb094SRafael J. Wysocki * Some callers expect the link creation during consumer driver probe to 43015cfb094SRafael J. Wysocki * resume the supplier even without DL_FLAG_RPM_ACTIVE. 43115cfb094SRafael J. Wysocki */ 43215cfb094SRafael J. Wysocki if (link->status == DL_STATE_CONSUMER_PROBE && 43315cfb094SRafael J. Wysocki flags & DL_FLAG_PM_RUNTIME) 43415cfb094SRafael J. Wysocki pm_runtime_resume(supplier); 43515cfb094SRafael J. Wysocki 43605ef983eSSaravana Kannan if (flags & DL_FLAG_SYNC_STATE_ONLY) { 43705ef983eSSaravana Kannan dev_dbg(consumer, 43805ef983eSSaravana Kannan "Linked as a sync state only consumer to %s\n", 43905ef983eSSaravana Kannan dev_name(supplier)); 44005ef983eSSaravana Kannan goto out; 44105ef983eSSaravana Kannan } 44205ef983eSSaravana Kannan reorder: 44315cfb094SRafael J. Wysocki /* 4449ed98953SRafael J. Wysocki * Move the consumer and all of the devices depending on it to the end 4459ed98953SRafael J. Wysocki * of dpm_list and the devices_kset list. 4469ed98953SRafael J. Wysocki * 4479ed98953SRafael J. Wysocki * It is necessary to hold dpm_list locked throughout all that or else 4489ed98953SRafael J. Wysocki * we may end up suspending with a wrong ordering of it. 4499ed98953SRafael J. Wysocki */ 4509ed98953SRafael J. Wysocki device_reorder_to_tail(consumer, NULL); 4519ed98953SRafael J. Wysocki 4529ed98953SRafael J. Wysocki list_add_tail_rcu(&link->s_node, &supplier->links.consumers); 4539ed98953SRafael J. Wysocki list_add_tail_rcu(&link->c_node, &consumer->links.suppliers); 4549ed98953SRafael J. Wysocki 4558a4b3269SJerome Brunet dev_dbg(consumer, "Linked as a consumer to %s\n", dev_name(supplier)); 4569ed98953SRafael J. Wysocki 4579ed98953SRafael J. Wysocki out: 4589ed98953SRafael J. Wysocki device_pm_unlock(); 4599ed98953SRafael J. Wysocki device_links_write_unlock(); 4605db25c9eSRafael J. Wysocki 461e2f3cd83SRafael J. Wysocki if ((flags & DL_FLAG_PM_RUNTIME && flags & DL_FLAG_RPM_ACTIVE) && !link) 4625db25c9eSRafael J. Wysocki pm_runtime_put(supplier); 4635db25c9eSRafael J. Wysocki 4649ed98953SRafael J. Wysocki return link; 4659ed98953SRafael J. Wysocki } 4669ed98953SRafael J. Wysocki EXPORT_SYMBOL_GPL(device_link_add); 4679ed98953SRafael J. Wysocki 468e2ae9bccSSaravana Kannan /** 469e2ae9bccSSaravana Kannan * device_link_wait_for_supplier - Add device to wait_for_suppliers list 470e2ae9bccSSaravana Kannan * @consumer: Consumer device 471e2ae9bccSSaravana Kannan * 472e2ae9bccSSaravana Kannan * Marks the @consumer device as waiting for suppliers to become available by 473e2ae9bccSSaravana Kannan * adding it to the wait_for_suppliers list. The consumer device will never be 474e2ae9bccSSaravana Kannan * probed until it's removed from the wait_for_suppliers list. 475e2ae9bccSSaravana Kannan * 476e2ae9bccSSaravana Kannan * The caller is responsible for adding the links to the supplier devices once 477e2ae9bccSSaravana Kannan * they are available and removing the @consumer device from the 478e2ae9bccSSaravana Kannan * wait_for_suppliers list once links to all the suppliers have been created. 479e2ae9bccSSaravana Kannan * 480e2ae9bccSSaravana Kannan * This function is NOT meant to be called from the probe function of the 481e2ae9bccSSaravana Kannan * consumer but rather from code that creates/adds the consumer device. 482e2ae9bccSSaravana Kannan */ 483bcbbcfd5SSaravana Kannan static void device_link_wait_for_supplier(struct device *consumer, 484bcbbcfd5SSaravana Kannan bool need_for_probe) 485e2ae9bccSSaravana Kannan { 486e2ae9bccSSaravana Kannan mutex_lock(&wfs_lock); 487e2ae9bccSSaravana Kannan list_add_tail(&consumer->links.needs_suppliers, &wait_for_suppliers); 488bcbbcfd5SSaravana Kannan consumer->links.need_for_probe = need_for_probe; 489e2ae9bccSSaravana Kannan mutex_unlock(&wfs_lock); 490e2ae9bccSSaravana Kannan } 491e2ae9bccSSaravana Kannan 492bcbbcfd5SSaravana Kannan static void device_link_wait_for_mandatory_supplier(struct device *consumer) 493bcbbcfd5SSaravana Kannan { 494bcbbcfd5SSaravana Kannan device_link_wait_for_supplier(consumer, true); 495bcbbcfd5SSaravana Kannan } 496bcbbcfd5SSaravana Kannan 497bcbbcfd5SSaravana Kannan static void device_link_wait_for_optional_supplier(struct device *consumer) 498bcbbcfd5SSaravana Kannan { 499bcbbcfd5SSaravana Kannan device_link_wait_for_supplier(consumer, false); 500bcbbcfd5SSaravana Kannan } 501bcbbcfd5SSaravana Kannan 502e2ae9bccSSaravana Kannan /** 503e2ae9bccSSaravana Kannan * device_link_add_missing_supplier_links - Add links from consumer devices to 504e2ae9bccSSaravana Kannan * supplier devices, leaving any 505e2ae9bccSSaravana Kannan * consumer with inactive suppliers on 506e2ae9bccSSaravana Kannan * the wait_for_suppliers list 507e2ae9bccSSaravana Kannan * 508e2ae9bccSSaravana Kannan * Loops through all consumers waiting on suppliers and tries to add all their 509e2ae9bccSSaravana Kannan * supplier links. If that succeeds, the consumer device is removed from 510e2ae9bccSSaravana Kannan * wait_for_suppliers list. Otherwise, they are left in the wait_for_suppliers 511e2ae9bccSSaravana Kannan * list. Devices left on the wait_for_suppliers list will not be probed. 512e2ae9bccSSaravana Kannan * 513e2ae9bccSSaravana Kannan * The fwnode add_links callback is expected to return 0 if it has found and 514e2ae9bccSSaravana Kannan * added all the supplier links for the consumer device. It should return an 515e2ae9bccSSaravana Kannan * error if it isn't able to do so. 516e2ae9bccSSaravana Kannan * 517e2ae9bccSSaravana Kannan * The caller of device_link_wait_for_supplier() is expected to call this once 518e2ae9bccSSaravana Kannan * it's aware of potential suppliers becoming available. 519e2ae9bccSSaravana Kannan */ 520e2ae9bccSSaravana Kannan static void device_link_add_missing_supplier_links(void) 521e2ae9bccSSaravana Kannan { 522e2ae9bccSSaravana Kannan struct device *dev, *tmp; 523e2ae9bccSSaravana Kannan 524e2ae9bccSSaravana Kannan mutex_lock(&wfs_lock); 525e2ae9bccSSaravana Kannan list_for_each_entry_safe(dev, tmp, &wait_for_suppliers, 526e2ae9bccSSaravana Kannan links.needs_suppliers) 527e2ae9bccSSaravana Kannan if (!fwnode_call_int_op(dev->fwnode, add_links, dev)) 528e2ae9bccSSaravana Kannan list_del_init(&dev->links.needs_suppliers); 529e2ae9bccSSaravana Kannan mutex_unlock(&wfs_lock); 530e2ae9bccSSaravana Kannan } 531e2ae9bccSSaravana Kannan 5329ed98953SRafael J. Wysocki static void device_link_free(struct device_link *link) 5339ed98953SRafael J. Wysocki { 534a1fdbfbbSRafael J. Wysocki while (refcount_dec_not_one(&link->rpm_active)) 535a1fdbfbbSRafael J. Wysocki pm_runtime_put(link->supplier); 536a1fdbfbbSRafael J. Wysocki 5379ed98953SRafael J. Wysocki put_device(link->consumer); 5389ed98953SRafael J. Wysocki put_device(link->supplier); 5399ed98953SRafael J. Wysocki kfree(link); 5409ed98953SRafael J. Wysocki } 5419ed98953SRafael J. Wysocki 5429ed98953SRafael J. Wysocki #ifdef CONFIG_SRCU 5439ed98953SRafael J. Wysocki static void __device_link_free_srcu(struct rcu_head *rhead) 5449ed98953SRafael J. Wysocki { 5459ed98953SRafael J. Wysocki device_link_free(container_of(rhead, struct device_link, rcu_head)); 5469ed98953SRafael J. Wysocki } 5479ed98953SRafael J. Wysocki 548ead18c23SLukas Wunner static void __device_link_del(struct kref *kref) 5499ed98953SRafael J. Wysocki { 550ead18c23SLukas Wunner struct device_link *link = container_of(kref, struct device_link, kref); 551ead18c23SLukas Wunner 5528a4b3269SJerome Brunet dev_dbg(link->consumer, "Dropping the link to %s\n", 5539ed98953SRafael J. Wysocki dev_name(link->supplier)); 5549ed98953SRafael J. Wysocki 555baa8809fSRafael J. Wysocki if (link->flags & DL_FLAG_PM_RUNTIME) 556baa8809fSRafael J. Wysocki pm_runtime_drop_link(link->consumer); 557baa8809fSRafael J. Wysocki 5589ed98953SRafael J. Wysocki list_del_rcu(&link->s_node); 5599ed98953SRafael J. Wysocki list_del_rcu(&link->c_node); 5609ed98953SRafael J. Wysocki call_srcu(&device_links_srcu, &link->rcu_head, __device_link_free_srcu); 5619ed98953SRafael J. Wysocki } 5629ed98953SRafael J. Wysocki #else /* !CONFIG_SRCU */ 563ead18c23SLukas Wunner static void __device_link_del(struct kref *kref) 5649ed98953SRafael J. Wysocki { 565ead18c23SLukas Wunner struct device_link *link = container_of(kref, struct device_link, kref); 566ead18c23SLukas Wunner 5679ed98953SRafael J. Wysocki dev_info(link->consumer, "Dropping the link to %s\n", 5689ed98953SRafael J. Wysocki dev_name(link->supplier)); 5699ed98953SRafael J. Wysocki 570433986c2SLukas Wunner if (link->flags & DL_FLAG_PM_RUNTIME) 571433986c2SLukas Wunner pm_runtime_drop_link(link->consumer); 572433986c2SLukas Wunner 5739ed98953SRafael J. Wysocki list_del(&link->s_node); 5749ed98953SRafael J. Wysocki list_del(&link->c_node); 5759ed98953SRafael J. Wysocki device_link_free(link); 5769ed98953SRafael J. Wysocki } 5779ed98953SRafael J. Wysocki #endif /* !CONFIG_SRCU */ 5789ed98953SRafael J. Wysocki 57972175d4eSRafael J. Wysocki static void device_link_put_kref(struct device_link *link) 58072175d4eSRafael J. Wysocki { 58172175d4eSRafael J. Wysocki if (link->flags & DL_FLAG_STATELESS) 58272175d4eSRafael J. Wysocki kref_put(&link->kref, __device_link_del); 58372175d4eSRafael J. Wysocki else 58472175d4eSRafael J. Wysocki WARN(1, "Unable to drop a managed device link reference\n"); 58572175d4eSRafael J. Wysocki } 58672175d4eSRafael J. Wysocki 5879ed98953SRafael J. Wysocki /** 58872175d4eSRafael J. Wysocki * device_link_del - Delete a stateless link between two devices. 5899ed98953SRafael J. Wysocki * @link: Device link to delete. 5909ed98953SRafael J. Wysocki * 5919ed98953SRafael J. Wysocki * The caller must ensure proper synchronization of this function with runtime 592ead18c23SLukas Wunner * PM. If the link was added multiple times, it needs to be deleted as often. 593ead18c23SLukas Wunner * Care is required for hotplugged devices: Their links are purged on removal 594ead18c23SLukas Wunner * and calling device_link_del() is then no longer allowed. 5959ed98953SRafael J. Wysocki */ 5969ed98953SRafael J. Wysocki void device_link_del(struct device_link *link) 5979ed98953SRafael J. Wysocki { 5989ed98953SRafael J. Wysocki device_links_write_lock(); 5999ed98953SRafael J. Wysocki device_pm_lock(); 60072175d4eSRafael J. Wysocki device_link_put_kref(link); 6019ed98953SRafael J. Wysocki device_pm_unlock(); 6029ed98953SRafael J. Wysocki device_links_write_unlock(); 6039ed98953SRafael J. Wysocki } 6049ed98953SRafael J. Wysocki EXPORT_SYMBOL_GPL(device_link_del); 6059ed98953SRafael J. Wysocki 606d8842211Spascal paillet /** 60772175d4eSRafael J. Wysocki * device_link_remove - Delete a stateless link between two devices. 608d8842211Spascal paillet * @consumer: Consumer end of the link. 609d8842211Spascal paillet * @supplier: Supplier end of the link. 610d8842211Spascal paillet * 611d8842211Spascal paillet * The caller must ensure proper synchronization of this function with runtime 612d8842211Spascal paillet * PM. 613d8842211Spascal paillet */ 614d8842211Spascal paillet void device_link_remove(void *consumer, struct device *supplier) 615d8842211Spascal paillet { 616d8842211Spascal paillet struct device_link *link; 617d8842211Spascal paillet 618d8842211Spascal paillet if (WARN_ON(consumer == supplier)) 619d8842211Spascal paillet return; 620d8842211Spascal paillet 621d8842211Spascal paillet device_links_write_lock(); 622d8842211Spascal paillet device_pm_lock(); 623d8842211Spascal paillet 624d8842211Spascal paillet list_for_each_entry(link, &supplier->links.consumers, s_node) { 625d8842211Spascal paillet if (link->consumer == consumer) { 62672175d4eSRafael J. Wysocki device_link_put_kref(link); 627d8842211Spascal paillet break; 628d8842211Spascal paillet } 629d8842211Spascal paillet } 630d8842211Spascal paillet 631d8842211Spascal paillet device_pm_unlock(); 632d8842211Spascal paillet device_links_write_unlock(); 633d8842211Spascal paillet } 634d8842211Spascal paillet EXPORT_SYMBOL_GPL(device_link_remove); 635d8842211Spascal paillet 6369ed98953SRafael J. Wysocki static void device_links_missing_supplier(struct device *dev) 6379ed98953SRafael J. Wysocki { 6389ed98953SRafael J. Wysocki struct device_link *link; 6399ed98953SRafael J. Wysocki 6409ed98953SRafael J. Wysocki list_for_each_entry(link, &dev->links.suppliers, c_node) 6419ed98953SRafael J. Wysocki if (link->status == DL_STATE_CONSUMER_PROBE) 6429ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_AVAILABLE); 6439ed98953SRafael J. Wysocki } 6449ed98953SRafael J. Wysocki 6459ed98953SRafael J. Wysocki /** 6469ed98953SRafael J. Wysocki * device_links_check_suppliers - Check presence of supplier drivers. 6479ed98953SRafael J. Wysocki * @dev: Consumer device. 6489ed98953SRafael J. Wysocki * 6499ed98953SRafael J. Wysocki * Check links from this device to any suppliers. Walk the list of the device's 6509ed98953SRafael J. Wysocki * links to suppliers and see if all of them are available. If not, simply 6519ed98953SRafael J. Wysocki * return -EPROBE_DEFER. 6529ed98953SRafael J. Wysocki * 6539ed98953SRafael J. Wysocki * We need to guarantee that the supplier will not go away after the check has 6549ed98953SRafael J. Wysocki * been positive here. It only can go away in __device_release_driver() and 6559ed98953SRafael J. Wysocki * that function checks the device's links to consumers. This means we need to 6569ed98953SRafael J. Wysocki * mark the link as "consumer probe in progress" to make the supplier removal 6579ed98953SRafael J. Wysocki * wait for us to complete (or bad things may happen). 6589ed98953SRafael J. Wysocki * 659515db266SRafael J. Wysocki * Links without the DL_FLAG_MANAGED flag set are ignored. 6609ed98953SRafael J. Wysocki */ 6619ed98953SRafael J. Wysocki int device_links_check_suppliers(struct device *dev) 6629ed98953SRafael J. Wysocki { 6639ed98953SRafael J. Wysocki struct device_link *link; 6649ed98953SRafael J. Wysocki int ret = 0; 6659ed98953SRafael J. Wysocki 666e2ae9bccSSaravana Kannan /* 667e2ae9bccSSaravana Kannan * Device waiting for supplier to become available is not allowed to 668e2ae9bccSSaravana Kannan * probe. 669e2ae9bccSSaravana Kannan */ 670e2ae9bccSSaravana Kannan mutex_lock(&wfs_lock); 671bcbbcfd5SSaravana Kannan if (!list_empty(&dev->links.needs_suppliers) && 672bcbbcfd5SSaravana Kannan dev->links.need_for_probe) { 673e2ae9bccSSaravana Kannan mutex_unlock(&wfs_lock); 674e2ae9bccSSaravana Kannan return -EPROBE_DEFER; 675e2ae9bccSSaravana Kannan } 676e2ae9bccSSaravana Kannan mutex_unlock(&wfs_lock); 677e2ae9bccSSaravana Kannan 6789ed98953SRafael J. Wysocki device_links_write_lock(); 6799ed98953SRafael J. Wysocki 6809ed98953SRafael J. Wysocki list_for_each_entry(link, &dev->links.suppliers, c_node) { 68105ef983eSSaravana Kannan if (!(link->flags & DL_FLAG_MANAGED) || 68205ef983eSSaravana Kannan link->flags & DL_FLAG_SYNC_STATE_ONLY) 6839ed98953SRafael J. Wysocki continue; 6849ed98953SRafael J. Wysocki 6859ed98953SRafael J. Wysocki if (link->status != DL_STATE_AVAILABLE) { 6869ed98953SRafael J. Wysocki device_links_missing_supplier(dev); 6879ed98953SRafael J. Wysocki ret = -EPROBE_DEFER; 6889ed98953SRafael J. Wysocki break; 6899ed98953SRafael J. Wysocki } 6909ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_CONSUMER_PROBE); 6919ed98953SRafael J. Wysocki } 6929ed98953SRafael J. Wysocki dev->links.status = DL_DEV_PROBING; 6939ed98953SRafael J. Wysocki 6949ed98953SRafael J. Wysocki device_links_write_unlock(); 6959ed98953SRafael J. Wysocki return ret; 6969ed98953SRafael J. Wysocki } 6979ed98953SRafael J. Wysocki 69826e77708SSaravana Kannan /** 69926e77708SSaravana Kannan * __device_links_queue_sync_state - Queue a device for sync_state() callback 70026e77708SSaravana Kannan * @dev: Device to call sync_state() on 70126e77708SSaravana Kannan * @list: List head to queue the @dev on 70226e77708SSaravana Kannan * 70326e77708SSaravana Kannan * Queues a device for a sync_state() callback when the device links write lock 70426e77708SSaravana Kannan * isn't held. This allows the sync_state() execution flow to use device links 70526e77708SSaravana Kannan * APIs. The caller must ensure this function is called with 70626e77708SSaravana Kannan * device_links_write_lock() held. 70726e77708SSaravana Kannan * 70826e77708SSaravana Kannan * This function does a get_device() to make sure the device is not freed while 70926e77708SSaravana Kannan * on this list. 71026e77708SSaravana Kannan * 71126e77708SSaravana Kannan * So the caller must also ensure that device_links_flush_sync_list() is called 71226e77708SSaravana Kannan * as soon as the caller releases device_links_write_lock(). This is necessary 71326e77708SSaravana Kannan * to make sure the sync_state() is called in a timely fashion and the 71426e77708SSaravana Kannan * put_device() is called on this device. 71526e77708SSaravana Kannan */ 71626e77708SSaravana Kannan static void __device_links_queue_sync_state(struct device *dev, 71726e77708SSaravana Kannan struct list_head *list) 718fc5a251dSSaravana Kannan { 719fc5a251dSSaravana Kannan struct device_link *link; 720fc5a251dSSaravana Kannan 72177036165SSaravana Kannan if (!dev_has_sync_state(dev)) 72277036165SSaravana Kannan return; 723fc5a251dSSaravana Kannan if (dev->state_synced) 724fc5a251dSSaravana Kannan return; 725fc5a251dSSaravana Kannan 726fc5a251dSSaravana Kannan list_for_each_entry(link, &dev->links.consumers, s_node) { 727fc5a251dSSaravana Kannan if (!(link->flags & DL_FLAG_MANAGED)) 728fc5a251dSSaravana Kannan continue; 729fc5a251dSSaravana Kannan if (link->status != DL_STATE_ACTIVE) 730fc5a251dSSaravana Kannan return; 731fc5a251dSSaravana Kannan } 732fc5a251dSSaravana Kannan 73326e77708SSaravana Kannan /* 73426e77708SSaravana Kannan * Set the flag here to avoid adding the same device to a list more 73526e77708SSaravana Kannan * than once. This can happen if new consumers get added to the device 73626e77708SSaravana Kannan * and probed before the list is flushed. 73726e77708SSaravana Kannan */ 73826e77708SSaravana Kannan dev->state_synced = true; 73926e77708SSaravana Kannan 74026e77708SSaravana Kannan if (WARN_ON(!list_empty(&dev->links.defer_sync))) 74126e77708SSaravana Kannan return; 74226e77708SSaravana Kannan 74326e77708SSaravana Kannan get_device(dev); 74426e77708SSaravana Kannan list_add_tail(&dev->links.defer_sync, list); 74526e77708SSaravana Kannan } 74626e77708SSaravana Kannan 74726e77708SSaravana Kannan /** 74826e77708SSaravana Kannan * device_links_flush_sync_list - Call sync_state() on a list of devices 74926e77708SSaravana Kannan * @list: List of devices to call sync_state() on 75021eb93f4SSaravana Kannan * @dont_lock_dev: Device for which lock is already held by the caller 75126e77708SSaravana Kannan * 75226e77708SSaravana Kannan * Calls sync_state() on all the devices that have been queued for it. This 75321eb93f4SSaravana Kannan * function is used in conjunction with __device_links_queue_sync_state(). The 75421eb93f4SSaravana Kannan * @dont_lock_dev parameter is useful when this function is called from a 75521eb93f4SSaravana Kannan * context where a device lock is already held. 75626e77708SSaravana Kannan */ 75721eb93f4SSaravana Kannan static void device_links_flush_sync_list(struct list_head *list, 75821eb93f4SSaravana Kannan struct device *dont_lock_dev) 75926e77708SSaravana Kannan { 76026e77708SSaravana Kannan struct device *dev, *tmp; 76126e77708SSaravana Kannan 76226e77708SSaravana Kannan list_for_each_entry_safe(dev, tmp, list, links.defer_sync) { 76326e77708SSaravana Kannan list_del_init(&dev->links.defer_sync); 76426e77708SSaravana Kannan 76521eb93f4SSaravana Kannan if (dev != dont_lock_dev) 76626e77708SSaravana Kannan device_lock(dev); 76726e77708SSaravana Kannan 768fc5a251dSSaravana Kannan if (dev->bus->sync_state) 769fc5a251dSSaravana Kannan dev->bus->sync_state(dev); 770fc5a251dSSaravana Kannan else if (dev->driver && dev->driver->sync_state) 771fc5a251dSSaravana Kannan dev->driver->sync_state(dev); 772fc5a251dSSaravana Kannan 77321eb93f4SSaravana Kannan if (dev != dont_lock_dev) 77426e77708SSaravana Kannan device_unlock(dev); 77526e77708SSaravana Kannan 77626e77708SSaravana Kannan put_device(dev); 77726e77708SSaravana Kannan } 778fc5a251dSSaravana Kannan } 779fc5a251dSSaravana Kannan 780fc5a251dSSaravana Kannan void device_links_supplier_sync_state_pause(void) 781fc5a251dSSaravana Kannan { 782fc5a251dSSaravana Kannan device_links_write_lock(); 783fc5a251dSSaravana Kannan defer_sync_state_count++; 784fc5a251dSSaravana Kannan device_links_write_unlock(); 785fc5a251dSSaravana Kannan } 786fc5a251dSSaravana Kannan 787fc5a251dSSaravana Kannan void device_links_supplier_sync_state_resume(void) 788fc5a251dSSaravana Kannan { 789fc5a251dSSaravana Kannan struct device *dev, *tmp; 79026e77708SSaravana Kannan LIST_HEAD(sync_list); 791fc5a251dSSaravana Kannan 792fc5a251dSSaravana Kannan device_links_write_lock(); 793fc5a251dSSaravana Kannan if (!defer_sync_state_count) { 794fc5a251dSSaravana Kannan WARN(true, "Unmatched sync_state pause/resume!"); 795fc5a251dSSaravana Kannan goto out; 796fc5a251dSSaravana Kannan } 797fc5a251dSSaravana Kannan defer_sync_state_count--; 798fc5a251dSSaravana Kannan if (defer_sync_state_count) 799fc5a251dSSaravana Kannan goto out; 800fc5a251dSSaravana Kannan 801fc5a251dSSaravana Kannan list_for_each_entry_safe(dev, tmp, &deferred_sync, links.defer_sync) { 80226e77708SSaravana Kannan /* 80326e77708SSaravana Kannan * Delete from deferred_sync list before queuing it to 80426e77708SSaravana Kannan * sync_list because defer_sync is used for both lists. 80526e77708SSaravana Kannan */ 806fc5a251dSSaravana Kannan list_del_init(&dev->links.defer_sync); 80726e77708SSaravana Kannan __device_links_queue_sync_state(dev, &sync_list); 808fc5a251dSSaravana Kannan } 809fc5a251dSSaravana Kannan out: 810fc5a251dSSaravana Kannan device_links_write_unlock(); 81126e77708SSaravana Kannan 81221eb93f4SSaravana Kannan device_links_flush_sync_list(&sync_list, NULL); 813fc5a251dSSaravana Kannan } 814fc5a251dSSaravana Kannan 815fc5a251dSSaravana Kannan static int sync_state_resume_initcall(void) 816fc5a251dSSaravana Kannan { 817fc5a251dSSaravana Kannan device_links_supplier_sync_state_resume(); 818fc5a251dSSaravana Kannan return 0; 819fc5a251dSSaravana Kannan } 820fc5a251dSSaravana Kannan late_initcall(sync_state_resume_initcall); 821fc5a251dSSaravana Kannan 822fc5a251dSSaravana Kannan static void __device_links_supplier_defer_sync(struct device *sup) 823fc5a251dSSaravana Kannan { 82477036165SSaravana Kannan if (list_empty(&sup->links.defer_sync) && dev_has_sync_state(sup)) 825fc5a251dSSaravana Kannan list_add_tail(&sup->links.defer_sync, &deferred_sync); 826fc5a251dSSaravana Kannan } 827fc5a251dSSaravana Kannan 8289ed98953SRafael J. Wysocki /** 8299ed98953SRafael J. Wysocki * device_links_driver_bound - Update device links after probing its driver. 8309ed98953SRafael J. Wysocki * @dev: Device to update the links for. 8319ed98953SRafael J. Wysocki * 8329ed98953SRafael J. Wysocki * The probe has been successful, so update links from this device to any 8339ed98953SRafael J. Wysocki * consumers by changing their status to "available". 8349ed98953SRafael J. Wysocki * 8359ed98953SRafael J. Wysocki * Also change the status of @dev's links to suppliers to "active". 8369ed98953SRafael J. Wysocki * 837515db266SRafael J. Wysocki * Links without the DL_FLAG_MANAGED flag set are ignored. 8389ed98953SRafael J. Wysocki */ 8399ed98953SRafael J. Wysocki void device_links_driver_bound(struct device *dev) 8409ed98953SRafael J. Wysocki { 8419ed98953SRafael J. Wysocki struct device_link *link; 84226e77708SSaravana Kannan LIST_HEAD(sync_list); 8439ed98953SRafael J. Wysocki 844bcbbcfd5SSaravana Kannan /* 845bcbbcfd5SSaravana Kannan * If a device probes successfully, it's expected to have created all 846bcbbcfd5SSaravana Kannan * the device links it needs to or make new device links as it needs 847bcbbcfd5SSaravana Kannan * them. So, it no longer needs to wait on any suppliers. 848bcbbcfd5SSaravana Kannan */ 849bcbbcfd5SSaravana Kannan mutex_lock(&wfs_lock); 850bcbbcfd5SSaravana Kannan list_del_init(&dev->links.needs_suppliers); 851bcbbcfd5SSaravana Kannan mutex_unlock(&wfs_lock); 852bcbbcfd5SSaravana Kannan 8539ed98953SRafael J. Wysocki device_links_write_lock(); 8549ed98953SRafael J. Wysocki 8559ed98953SRafael J. Wysocki list_for_each_entry(link, &dev->links.consumers, s_node) { 856515db266SRafael J. Wysocki if (!(link->flags & DL_FLAG_MANAGED)) 8579ed98953SRafael J. Wysocki continue; 8589ed98953SRafael J. Wysocki 85915cfb094SRafael J. Wysocki /* 86015cfb094SRafael J. Wysocki * Links created during consumer probe may be in the "consumer 86115cfb094SRafael J. Wysocki * probe" state to start with if the supplier is still probing 86215cfb094SRafael J. Wysocki * when they are created and they may become "active" if the 86315cfb094SRafael J. Wysocki * consumer probe returns first. Skip them here. 86415cfb094SRafael J. Wysocki */ 86515cfb094SRafael J. Wysocki if (link->status == DL_STATE_CONSUMER_PROBE || 86615cfb094SRafael J. Wysocki link->status == DL_STATE_ACTIVE) 86715cfb094SRafael J. Wysocki continue; 86815cfb094SRafael J. Wysocki 8699ed98953SRafael J. Wysocki WARN_ON(link->status != DL_STATE_DORMANT); 8709ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_AVAILABLE); 871e7dd4010SRafael J. Wysocki 872e7dd4010SRafael J. Wysocki if (link->flags & DL_FLAG_AUTOPROBE_CONSUMER) 873e7dd4010SRafael J. Wysocki driver_deferred_probe_add(link->consumer); 8749ed98953SRafael J. Wysocki } 8759ed98953SRafael J. Wysocki 87621eb93f4SSaravana Kannan if (defer_sync_state_count) 87721eb93f4SSaravana Kannan __device_links_supplier_defer_sync(dev); 87821eb93f4SSaravana Kannan else 87921eb93f4SSaravana Kannan __device_links_queue_sync_state(dev, &sync_list); 88021eb93f4SSaravana Kannan 8819ed98953SRafael J. Wysocki list_for_each_entry(link, &dev->links.suppliers, c_node) { 882515db266SRafael J. Wysocki if (!(link->flags & DL_FLAG_MANAGED)) 8839ed98953SRafael J. Wysocki continue; 8849ed98953SRafael J. Wysocki 8859ed98953SRafael J. Wysocki WARN_ON(link->status != DL_STATE_CONSUMER_PROBE); 8869ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_ACTIVE); 887fc5a251dSSaravana Kannan 888fc5a251dSSaravana Kannan if (defer_sync_state_count) 889fc5a251dSSaravana Kannan __device_links_supplier_defer_sync(link->supplier); 890fc5a251dSSaravana Kannan else 89126e77708SSaravana Kannan __device_links_queue_sync_state(link->supplier, 89226e77708SSaravana Kannan &sync_list); 8939ed98953SRafael J. Wysocki } 8949ed98953SRafael J. Wysocki 8959ed98953SRafael J. Wysocki dev->links.status = DL_DEV_DRIVER_BOUND; 8969ed98953SRafael J. Wysocki 8979ed98953SRafael J. Wysocki device_links_write_unlock(); 89826e77708SSaravana Kannan 89921eb93f4SSaravana Kannan device_links_flush_sync_list(&sync_list, dev); 9009ed98953SRafael J. Wysocki } 9019ed98953SRafael J. Wysocki 902515db266SRafael J. Wysocki static void device_link_drop_managed(struct device_link *link) 903515db266SRafael J. Wysocki { 904515db266SRafael J. Wysocki link->flags &= ~DL_FLAG_MANAGED; 905515db266SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_NONE); 906515db266SRafael J. Wysocki kref_put(&link->kref, __device_link_del); 907515db266SRafael J. Wysocki } 908515db266SRafael J. Wysocki 9099ed98953SRafael J. Wysocki /** 9109ed98953SRafael J. Wysocki * __device_links_no_driver - Update links of a device without a driver. 9119ed98953SRafael J. Wysocki * @dev: Device without a drvier. 9129ed98953SRafael J. Wysocki * 9139ed98953SRafael J. Wysocki * Delete all non-persistent links from this device to any suppliers. 9149ed98953SRafael J. Wysocki * 9159ed98953SRafael J. Wysocki * Persistent links stay around, but their status is changed to "available", 9169ed98953SRafael J. Wysocki * unless they already are in the "supplier unbind in progress" state in which 9179ed98953SRafael J. Wysocki * case they need not be updated. 9189ed98953SRafael J. Wysocki * 919515db266SRafael J. Wysocki * Links without the DL_FLAG_MANAGED flag set are ignored. 9209ed98953SRafael J. Wysocki */ 9219ed98953SRafael J. Wysocki static void __device_links_no_driver(struct device *dev) 9229ed98953SRafael J. Wysocki { 9239ed98953SRafael J. Wysocki struct device_link *link, *ln; 9249ed98953SRafael J. Wysocki 9259ed98953SRafael J. Wysocki list_for_each_entry_safe_reverse(link, ln, &dev->links.suppliers, c_node) { 926515db266SRafael J. Wysocki if (!(link->flags & DL_FLAG_MANAGED)) 9279ed98953SRafael J. Wysocki continue; 9289ed98953SRafael J. Wysocki 929e88728f4SVivek Gautam if (link->flags & DL_FLAG_AUTOREMOVE_CONSUMER) 930515db266SRafael J. Wysocki device_link_drop_managed(link); 93115cfb094SRafael J. Wysocki else if (link->status == DL_STATE_CONSUMER_PROBE || 93215cfb094SRafael J. Wysocki link->status == DL_STATE_ACTIVE) 9339ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_AVAILABLE); 9349ed98953SRafael J. Wysocki } 9359ed98953SRafael J. Wysocki 9369ed98953SRafael J. Wysocki dev->links.status = DL_DEV_NO_DRIVER; 9379ed98953SRafael J. Wysocki } 9389ed98953SRafael J. Wysocki 93915cfb094SRafael J. Wysocki /** 94015cfb094SRafael J. Wysocki * device_links_no_driver - Update links after failing driver probe. 94115cfb094SRafael J. Wysocki * @dev: Device whose driver has just failed to probe. 94215cfb094SRafael J. Wysocki * 94315cfb094SRafael J. Wysocki * Clean up leftover links to consumers for @dev and invoke 94415cfb094SRafael J. Wysocki * %__device_links_no_driver() to update links to suppliers for it as 94515cfb094SRafael J. Wysocki * appropriate. 94615cfb094SRafael J. Wysocki * 947515db266SRafael J. Wysocki * Links without the DL_FLAG_MANAGED flag set are ignored. 94815cfb094SRafael J. Wysocki */ 9499ed98953SRafael J. Wysocki void device_links_no_driver(struct device *dev) 9509ed98953SRafael J. Wysocki { 95115cfb094SRafael J. Wysocki struct device_link *link; 95215cfb094SRafael J. Wysocki 9539ed98953SRafael J. Wysocki device_links_write_lock(); 95415cfb094SRafael J. Wysocki 95515cfb094SRafael J. Wysocki list_for_each_entry(link, &dev->links.consumers, s_node) { 956515db266SRafael J. Wysocki if (!(link->flags & DL_FLAG_MANAGED)) 95715cfb094SRafael J. Wysocki continue; 95815cfb094SRafael J. Wysocki 95915cfb094SRafael J. Wysocki /* 96015cfb094SRafael J. Wysocki * The probe has failed, so if the status of the link is 96115cfb094SRafael J. Wysocki * "consumer probe" or "active", it must have been added by 96215cfb094SRafael J. Wysocki * a probing consumer while this device was still probing. 96315cfb094SRafael J. Wysocki * Change its state to "dormant", as it represents a valid 96415cfb094SRafael J. Wysocki * relationship, but it is not functionally meaningful. 96515cfb094SRafael J. Wysocki */ 96615cfb094SRafael J. Wysocki if (link->status == DL_STATE_CONSUMER_PROBE || 96715cfb094SRafael J. Wysocki link->status == DL_STATE_ACTIVE) 96815cfb094SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_DORMANT); 96915cfb094SRafael J. Wysocki } 97015cfb094SRafael J. Wysocki 9719ed98953SRafael J. Wysocki __device_links_no_driver(dev); 97215cfb094SRafael J. Wysocki 9739ed98953SRafael J. Wysocki device_links_write_unlock(); 9749ed98953SRafael J. Wysocki } 9759ed98953SRafael J. Wysocki 9769ed98953SRafael J. Wysocki /** 9779ed98953SRafael J. Wysocki * device_links_driver_cleanup - Update links after driver removal. 9789ed98953SRafael J. Wysocki * @dev: Device whose driver has just gone away. 9799ed98953SRafael J. Wysocki * 9809ed98953SRafael J. Wysocki * Update links to consumers for @dev by changing their status to "dormant" and 9819ed98953SRafael J. Wysocki * invoke %__device_links_no_driver() to update links to suppliers for it as 9829ed98953SRafael J. Wysocki * appropriate. 9839ed98953SRafael J. Wysocki * 984515db266SRafael J. Wysocki * Links without the DL_FLAG_MANAGED flag set are ignored. 9859ed98953SRafael J. Wysocki */ 9869ed98953SRafael J. Wysocki void device_links_driver_cleanup(struct device *dev) 9879ed98953SRafael J. Wysocki { 988c8d50986SRafael J. Wysocki struct device_link *link, *ln; 9899ed98953SRafael J. Wysocki 9909ed98953SRafael J. Wysocki device_links_write_lock(); 9919ed98953SRafael J. Wysocki 992c8d50986SRafael J. Wysocki list_for_each_entry_safe(link, ln, &dev->links.consumers, s_node) { 993515db266SRafael J. Wysocki if (!(link->flags & DL_FLAG_MANAGED)) 9949ed98953SRafael J. Wysocki continue; 9959ed98953SRafael J. Wysocki 996e88728f4SVivek Gautam WARN_ON(link->flags & DL_FLAG_AUTOREMOVE_CONSUMER); 9979ed98953SRafael J. Wysocki WARN_ON(link->status != DL_STATE_SUPPLIER_UNBIND); 9981689cac5SVivek Gautam 9991689cac5SVivek Gautam /* 10001689cac5SVivek Gautam * autoremove the links between this @dev and its consumer 10011689cac5SVivek Gautam * devices that are not active, i.e. where the link state 10021689cac5SVivek Gautam * has moved to DL_STATE_SUPPLIER_UNBIND. 10031689cac5SVivek Gautam */ 10041689cac5SVivek Gautam if (link->status == DL_STATE_SUPPLIER_UNBIND && 10051689cac5SVivek Gautam link->flags & DL_FLAG_AUTOREMOVE_SUPPLIER) 1006515db266SRafael J. Wysocki device_link_drop_managed(link); 10071689cac5SVivek Gautam 10089ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_DORMANT); 10099ed98953SRafael J. Wysocki } 10109ed98953SRafael J. Wysocki 1011fc5a251dSSaravana Kannan list_del_init(&dev->links.defer_sync); 10129ed98953SRafael J. Wysocki __device_links_no_driver(dev); 10139ed98953SRafael J. Wysocki 10149ed98953SRafael J. Wysocki device_links_write_unlock(); 10159ed98953SRafael J. Wysocki } 10169ed98953SRafael J. Wysocki 10179ed98953SRafael J. Wysocki /** 10189ed98953SRafael J. Wysocki * device_links_busy - Check if there are any busy links to consumers. 10199ed98953SRafael J. Wysocki * @dev: Device to check. 10209ed98953SRafael J. Wysocki * 10219ed98953SRafael J. Wysocki * Check each consumer of the device and return 'true' if its link's status 10229ed98953SRafael J. Wysocki * is one of "consumer probe" or "active" (meaning that the given consumer is 10239ed98953SRafael J. Wysocki * probing right now or its driver is present). Otherwise, change the link 10249ed98953SRafael J. Wysocki * state to "supplier unbind" to prevent the consumer from being probed 10259ed98953SRafael J. Wysocki * successfully going forward. 10269ed98953SRafael J. Wysocki * 10279ed98953SRafael J. Wysocki * Return 'false' if there are no probing or active consumers. 10289ed98953SRafael J. Wysocki * 1029515db266SRafael J. Wysocki * Links without the DL_FLAG_MANAGED flag set are ignored. 10309ed98953SRafael J. Wysocki */ 10319ed98953SRafael J. Wysocki bool device_links_busy(struct device *dev) 10329ed98953SRafael J. Wysocki { 10339ed98953SRafael J. Wysocki struct device_link *link; 10349ed98953SRafael J. Wysocki bool ret = false; 10359ed98953SRafael J. Wysocki 10369ed98953SRafael J. Wysocki device_links_write_lock(); 10379ed98953SRafael J. Wysocki 10389ed98953SRafael J. Wysocki list_for_each_entry(link, &dev->links.consumers, s_node) { 1039515db266SRafael J. Wysocki if (!(link->flags & DL_FLAG_MANAGED)) 10409ed98953SRafael J. Wysocki continue; 10419ed98953SRafael J. Wysocki 10429ed98953SRafael J. Wysocki if (link->status == DL_STATE_CONSUMER_PROBE 10439ed98953SRafael J. Wysocki || link->status == DL_STATE_ACTIVE) { 10449ed98953SRafael J. Wysocki ret = true; 10459ed98953SRafael J. Wysocki break; 10469ed98953SRafael J. Wysocki } 10479ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_SUPPLIER_UNBIND); 10489ed98953SRafael J. Wysocki } 10499ed98953SRafael J. Wysocki 10509ed98953SRafael J. Wysocki dev->links.status = DL_DEV_UNBINDING; 10519ed98953SRafael J. Wysocki 10529ed98953SRafael J. Wysocki device_links_write_unlock(); 10539ed98953SRafael J. Wysocki return ret; 10549ed98953SRafael J. Wysocki } 10559ed98953SRafael J. Wysocki 10569ed98953SRafael J. Wysocki /** 10579ed98953SRafael J. Wysocki * device_links_unbind_consumers - Force unbind consumers of the given device. 10589ed98953SRafael J. Wysocki * @dev: Device to unbind the consumers of. 10599ed98953SRafael J. Wysocki * 10609ed98953SRafael J. Wysocki * Walk the list of links to consumers for @dev and if any of them is in the 10619ed98953SRafael J. Wysocki * "consumer probe" state, wait for all device probes in progress to complete 10629ed98953SRafael J. Wysocki * and start over. 10639ed98953SRafael J. Wysocki * 10649ed98953SRafael J. Wysocki * If that's not the case, change the status of the link to "supplier unbind" 10659ed98953SRafael J. Wysocki * and check if the link was in the "active" state. If so, force the consumer 10669ed98953SRafael J. Wysocki * driver to unbind and start over (the consumer will not re-probe as we have 10679ed98953SRafael J. Wysocki * changed the state of the link already). 10689ed98953SRafael J. Wysocki * 1069515db266SRafael J. Wysocki * Links without the DL_FLAG_MANAGED flag set are ignored. 10709ed98953SRafael J. Wysocki */ 10719ed98953SRafael J. Wysocki void device_links_unbind_consumers(struct device *dev) 10729ed98953SRafael J. Wysocki { 10739ed98953SRafael J. Wysocki struct device_link *link; 10749ed98953SRafael J. Wysocki 10759ed98953SRafael J. Wysocki start: 10769ed98953SRafael J. Wysocki device_links_write_lock(); 10779ed98953SRafael J. Wysocki 10789ed98953SRafael J. Wysocki list_for_each_entry(link, &dev->links.consumers, s_node) { 10799ed98953SRafael J. Wysocki enum device_link_state status; 10809ed98953SRafael J. Wysocki 108105ef983eSSaravana Kannan if (!(link->flags & DL_FLAG_MANAGED) || 108205ef983eSSaravana Kannan link->flags & DL_FLAG_SYNC_STATE_ONLY) 10839ed98953SRafael J. Wysocki continue; 10849ed98953SRafael J. Wysocki 10859ed98953SRafael J. Wysocki status = link->status; 10869ed98953SRafael J. Wysocki if (status == DL_STATE_CONSUMER_PROBE) { 10879ed98953SRafael J. Wysocki device_links_write_unlock(); 10889ed98953SRafael J. Wysocki 10899ed98953SRafael J. Wysocki wait_for_device_probe(); 10909ed98953SRafael J. Wysocki goto start; 10919ed98953SRafael J. Wysocki } 10929ed98953SRafael J. Wysocki WRITE_ONCE(link->status, DL_STATE_SUPPLIER_UNBIND); 10939ed98953SRafael J. Wysocki if (status == DL_STATE_ACTIVE) { 10949ed98953SRafael J. Wysocki struct device *consumer = link->consumer; 10959ed98953SRafael J. Wysocki 10969ed98953SRafael J. Wysocki get_device(consumer); 10979ed98953SRafael J. Wysocki 10989ed98953SRafael J. Wysocki device_links_write_unlock(); 10999ed98953SRafael J. Wysocki 11009ed98953SRafael J. Wysocki device_release_driver_internal(consumer, NULL, 11019ed98953SRafael J. Wysocki consumer->parent); 11029ed98953SRafael J. Wysocki put_device(consumer); 11039ed98953SRafael J. Wysocki goto start; 11049ed98953SRafael J. Wysocki } 11059ed98953SRafael J. Wysocki } 11069ed98953SRafael J. Wysocki 11079ed98953SRafael J. Wysocki device_links_write_unlock(); 11089ed98953SRafael J. Wysocki } 11099ed98953SRafael J. Wysocki 11109ed98953SRafael J. Wysocki /** 11119ed98953SRafael J. Wysocki * device_links_purge - Delete existing links to other devices. 11129ed98953SRafael J. Wysocki * @dev: Target device. 11139ed98953SRafael J. Wysocki */ 11149ed98953SRafael J. Wysocki static void device_links_purge(struct device *dev) 11159ed98953SRafael J. Wysocki { 11169ed98953SRafael J. Wysocki struct device_link *link, *ln; 11179ed98953SRafael J. Wysocki 1118e2ae9bccSSaravana Kannan mutex_lock(&wfs_lock); 1119e2ae9bccSSaravana Kannan list_del(&dev->links.needs_suppliers); 1120e2ae9bccSSaravana Kannan mutex_unlock(&wfs_lock); 1121e2ae9bccSSaravana Kannan 11229ed98953SRafael J. Wysocki /* 11239ed98953SRafael J. Wysocki * Delete all of the remaining links from this device to any other 11249ed98953SRafael J. Wysocki * devices (either consumers or suppliers). 11259ed98953SRafael J. Wysocki */ 11269ed98953SRafael J. Wysocki device_links_write_lock(); 11279ed98953SRafael J. Wysocki 11289ed98953SRafael J. Wysocki list_for_each_entry_safe_reverse(link, ln, &dev->links.suppliers, c_node) { 11299ed98953SRafael J. Wysocki WARN_ON(link->status == DL_STATE_ACTIVE); 1130ead18c23SLukas Wunner __device_link_del(&link->kref); 11319ed98953SRafael J. Wysocki } 11329ed98953SRafael J. Wysocki 11339ed98953SRafael J. Wysocki list_for_each_entry_safe_reverse(link, ln, &dev->links.consumers, s_node) { 11349ed98953SRafael J. Wysocki WARN_ON(link->status != DL_STATE_DORMANT && 11359ed98953SRafael J. Wysocki link->status != DL_STATE_NONE); 1136ead18c23SLukas Wunner __device_link_del(&link->kref); 11379ed98953SRafael J. Wysocki } 11389ed98953SRafael J. Wysocki 11399ed98953SRafael J. Wysocki device_links_write_unlock(); 11409ed98953SRafael J. Wysocki } 11419ed98953SRafael J. Wysocki 11429ed98953SRafael J. Wysocki /* Device links support end. */ 11439ed98953SRafael J. Wysocki 11441da177e4SLinus Torvalds int (*platform_notify)(struct device *dev) = NULL; 11451da177e4SLinus Torvalds int (*platform_notify_remove)(struct device *dev) = NULL; 1146e105b8bfSDan Williams static struct kobject *dev_kobj; 1147e105b8bfSDan Williams struct kobject *sysfs_dev_char_kobj; 1148e105b8bfSDan Williams struct kobject *sysfs_dev_block_kobj; 11491da177e4SLinus Torvalds 11505e33bc41SRafael J. Wysocki static DEFINE_MUTEX(device_hotplug_lock); 11515e33bc41SRafael J. Wysocki 11525e33bc41SRafael J. Wysocki void lock_device_hotplug(void) 11535e33bc41SRafael J. Wysocki { 11545e33bc41SRafael J. Wysocki mutex_lock(&device_hotplug_lock); 11555e33bc41SRafael J. Wysocki } 11565e33bc41SRafael J. Wysocki 11575e33bc41SRafael J. Wysocki void unlock_device_hotplug(void) 11585e33bc41SRafael J. Wysocki { 11595e33bc41SRafael J. Wysocki mutex_unlock(&device_hotplug_lock); 11605e33bc41SRafael J. Wysocki } 11615e33bc41SRafael J. Wysocki 11625e33bc41SRafael J. Wysocki int lock_device_hotplug_sysfs(void) 11635e33bc41SRafael J. Wysocki { 11645e33bc41SRafael J. Wysocki if (mutex_trylock(&device_hotplug_lock)) 11655e33bc41SRafael J. Wysocki return 0; 11665e33bc41SRafael J. Wysocki 11675e33bc41SRafael J. Wysocki /* Avoid busy looping (5 ms of sleep should do). */ 11685e33bc41SRafael J. Wysocki msleep(5); 11695e33bc41SRafael J. Wysocki return restart_syscall(); 11705e33bc41SRafael J. Wysocki } 11715e33bc41SRafael J. Wysocki 11724e886c29SGreg Kroah-Hartman #ifdef CONFIG_BLOCK 11734e886c29SGreg Kroah-Hartman static inline int device_is_not_partition(struct device *dev) 11744e886c29SGreg Kroah-Hartman { 11754e886c29SGreg Kroah-Hartman return !(dev->type == &part_type); 11764e886c29SGreg Kroah-Hartman } 11774e886c29SGreg Kroah-Hartman #else 11784e886c29SGreg Kroah-Hartman static inline int device_is_not_partition(struct device *dev) 11794e886c29SGreg Kroah-Hartman { 11804e886c29SGreg Kroah-Hartman return 1; 11814e886c29SGreg Kroah-Hartman } 11824e886c29SGreg Kroah-Hartman #endif 11831da177e4SLinus Torvalds 118407de0e86SHeikki Krogerus static int 118507de0e86SHeikki Krogerus device_platform_notify(struct device *dev, enum kobject_action action) 118607de0e86SHeikki Krogerus { 11877847a145SHeikki Krogerus int ret; 11887847a145SHeikki Krogerus 11897847a145SHeikki Krogerus ret = acpi_platform_notify(dev, action); 11907847a145SHeikki Krogerus if (ret) 11917847a145SHeikki Krogerus return ret; 11927847a145SHeikki Krogerus 119359abd836SHeikki Krogerus ret = software_node_notify(dev, action); 119459abd836SHeikki Krogerus if (ret) 119559abd836SHeikki Krogerus return ret; 119659abd836SHeikki Krogerus 119707de0e86SHeikki Krogerus if (platform_notify && action == KOBJ_ADD) 119807de0e86SHeikki Krogerus platform_notify(dev); 119907de0e86SHeikki Krogerus else if (platform_notify_remove && action == KOBJ_REMOVE) 120007de0e86SHeikki Krogerus platform_notify_remove(dev); 120107de0e86SHeikki Krogerus return 0; 120207de0e86SHeikki Krogerus } 120307de0e86SHeikki Krogerus 12043e95637aSAlan Stern /** 12053e95637aSAlan Stern * dev_driver_string - Return a device's driver name, if at all possible 12063e95637aSAlan Stern * @dev: struct device to get the name of 12073e95637aSAlan Stern * 12083e95637aSAlan Stern * Will return the device's driver's name if it is bound to a device. If 12099169c012Syan * the device is not bound to a driver, it will return the name of the bus 12103e95637aSAlan Stern * it is attached to. If it is not attached to a bus either, an empty 12113e95637aSAlan Stern * string will be returned. 12123e95637aSAlan Stern */ 1213bf9ca69fSJean Delvare const char *dev_driver_string(const struct device *dev) 12143e95637aSAlan Stern { 12153589972eSAlan Stern struct device_driver *drv; 12163589972eSAlan Stern 12173589972eSAlan Stern /* dev->driver can change to NULL underneath us because of unbinding, 12183589972eSAlan Stern * so be careful about accessing it. dev->bus and dev->class should 12193589972eSAlan Stern * never change once they are set, so they don't need special care. 12203589972eSAlan Stern */ 12216aa7de05SMark Rutland drv = READ_ONCE(dev->driver); 12223589972eSAlan Stern return drv ? drv->name : 1223a456b702SJean Delvare (dev->bus ? dev->bus->name : 1224a456b702SJean Delvare (dev->class ? dev->class->name : "")); 12253e95637aSAlan Stern } 1226310a922dSMatthew Wilcox EXPORT_SYMBOL(dev_driver_string); 12273e95637aSAlan Stern 12281da177e4SLinus Torvalds #define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr) 12291da177e4SLinus Torvalds 12304a3ad20cSGreg Kroah-Hartman static ssize_t dev_attr_show(struct kobject *kobj, struct attribute *attr, 12314a3ad20cSGreg Kroah-Hartman char *buf) 12321da177e4SLinus Torvalds { 12331da177e4SLinus Torvalds struct device_attribute *dev_attr = to_dev_attr(attr); 1234b0d1f807SLars-Peter Clausen struct device *dev = kobj_to_dev(kobj); 12354a0c20bfSDmitry Torokhov ssize_t ret = -EIO; 12361da177e4SLinus Torvalds 12371da177e4SLinus Torvalds if (dev_attr->show) 123854b6f35cSYani Ioannou ret = dev_attr->show(dev, dev_attr, buf); 1239815d2d50SAndrew Morton if (ret >= (ssize_t)PAGE_SIZE) { 1240a52668c6SSergey Senozhatsky printk("dev_attr_show: %pS returned bad count\n", 1241a52668c6SSergey Senozhatsky dev_attr->show); 1242815d2d50SAndrew Morton } 12431da177e4SLinus Torvalds return ret; 12441da177e4SLinus Torvalds } 12451da177e4SLinus Torvalds 12464a3ad20cSGreg Kroah-Hartman static ssize_t dev_attr_store(struct kobject *kobj, struct attribute *attr, 12471da177e4SLinus Torvalds const char *buf, size_t count) 12481da177e4SLinus Torvalds { 12491da177e4SLinus Torvalds struct device_attribute *dev_attr = to_dev_attr(attr); 1250b0d1f807SLars-Peter Clausen struct device *dev = kobj_to_dev(kobj); 12514a0c20bfSDmitry Torokhov ssize_t ret = -EIO; 12521da177e4SLinus Torvalds 12531da177e4SLinus Torvalds if (dev_attr->store) 125454b6f35cSYani Ioannou ret = dev_attr->store(dev, dev_attr, buf, count); 12551da177e4SLinus Torvalds return ret; 12561da177e4SLinus Torvalds } 12571da177e4SLinus Torvalds 125852cf25d0SEmese Revfy static const struct sysfs_ops dev_sysfs_ops = { 12591da177e4SLinus Torvalds .show = dev_attr_show, 12601da177e4SLinus Torvalds .store = dev_attr_store, 12611da177e4SLinus Torvalds }; 12621da177e4SLinus Torvalds 1263ca22e56dSKay Sievers #define to_ext_attr(x) container_of(x, struct dev_ext_attribute, attr) 1264ca22e56dSKay Sievers 1265ca22e56dSKay Sievers ssize_t device_store_ulong(struct device *dev, 1266ca22e56dSKay Sievers struct device_attribute *attr, 1267ca22e56dSKay Sievers const char *buf, size_t size) 1268ca22e56dSKay Sievers { 1269ca22e56dSKay Sievers struct dev_ext_attribute *ea = to_ext_attr(attr); 1270f88184bfSKaitao cheng int ret; 1271f88184bfSKaitao cheng unsigned long new; 1272f88184bfSKaitao cheng 1273f88184bfSKaitao cheng ret = kstrtoul(buf, 0, &new); 1274f88184bfSKaitao cheng if (ret) 1275f88184bfSKaitao cheng return ret; 1276ca22e56dSKay Sievers *(unsigned long *)(ea->var) = new; 1277ca22e56dSKay Sievers /* Always return full write size even if we didn't consume all */ 1278ca22e56dSKay Sievers return size; 1279ca22e56dSKay Sievers } 1280ca22e56dSKay Sievers EXPORT_SYMBOL_GPL(device_store_ulong); 1281ca22e56dSKay Sievers 1282ca22e56dSKay Sievers ssize_t device_show_ulong(struct device *dev, 1283ca22e56dSKay Sievers struct device_attribute *attr, 1284ca22e56dSKay Sievers char *buf) 1285ca22e56dSKay Sievers { 1286ca22e56dSKay Sievers struct dev_ext_attribute *ea = to_ext_attr(attr); 1287ca22e56dSKay Sievers return snprintf(buf, PAGE_SIZE, "%lx\n", *(unsigned long *)(ea->var)); 1288ca22e56dSKay Sievers } 1289ca22e56dSKay Sievers EXPORT_SYMBOL_GPL(device_show_ulong); 1290ca22e56dSKay Sievers 1291ca22e56dSKay Sievers ssize_t device_store_int(struct device *dev, 1292ca22e56dSKay Sievers struct device_attribute *attr, 1293ca22e56dSKay Sievers const char *buf, size_t size) 1294ca22e56dSKay Sievers { 1295ca22e56dSKay Sievers struct dev_ext_attribute *ea = to_ext_attr(attr); 1296f88184bfSKaitao cheng int ret; 1297f88184bfSKaitao cheng long new; 1298f88184bfSKaitao cheng 1299f88184bfSKaitao cheng ret = kstrtol(buf, 0, &new); 1300f88184bfSKaitao cheng if (ret) 1301f88184bfSKaitao cheng return ret; 1302f88184bfSKaitao cheng 1303f88184bfSKaitao cheng if (new > INT_MAX || new < INT_MIN) 1304ca22e56dSKay Sievers return -EINVAL; 1305ca22e56dSKay Sievers *(int *)(ea->var) = new; 1306ca22e56dSKay Sievers /* Always return full write size even if we didn't consume all */ 1307ca22e56dSKay Sievers return size; 1308ca22e56dSKay Sievers } 1309ca22e56dSKay Sievers EXPORT_SYMBOL_GPL(device_store_int); 1310ca22e56dSKay Sievers 1311ca22e56dSKay Sievers ssize_t device_show_int(struct device *dev, 1312ca22e56dSKay Sievers struct device_attribute *attr, 1313ca22e56dSKay Sievers char *buf) 1314ca22e56dSKay Sievers { 1315ca22e56dSKay Sievers struct dev_ext_attribute *ea = to_ext_attr(attr); 1316ca22e56dSKay Sievers 1317ca22e56dSKay Sievers return snprintf(buf, PAGE_SIZE, "%d\n", *(int *)(ea->var)); 1318ca22e56dSKay Sievers } 1319ca22e56dSKay Sievers EXPORT_SYMBOL_GPL(device_show_int); 13201da177e4SLinus Torvalds 132191872392SBorislav Petkov ssize_t device_store_bool(struct device *dev, struct device_attribute *attr, 132291872392SBorislav Petkov const char *buf, size_t size) 132391872392SBorislav Petkov { 132491872392SBorislav Petkov struct dev_ext_attribute *ea = to_ext_attr(attr); 132591872392SBorislav Petkov 132691872392SBorislav Petkov if (strtobool(buf, ea->var) < 0) 132791872392SBorislav Petkov return -EINVAL; 132891872392SBorislav Petkov 132991872392SBorislav Petkov return size; 133091872392SBorislav Petkov } 133191872392SBorislav Petkov EXPORT_SYMBOL_GPL(device_store_bool); 133291872392SBorislav Petkov 133391872392SBorislav Petkov ssize_t device_show_bool(struct device *dev, struct device_attribute *attr, 133491872392SBorislav Petkov char *buf) 133591872392SBorislav Petkov { 133691872392SBorislav Petkov struct dev_ext_attribute *ea = to_ext_attr(attr); 133791872392SBorislav Petkov 133891872392SBorislav Petkov return snprintf(buf, PAGE_SIZE, "%d\n", *(bool *)(ea->var)); 133991872392SBorislav Petkov } 134091872392SBorislav Petkov EXPORT_SYMBOL_GPL(device_show_bool); 134191872392SBorislav Petkov 13421da177e4SLinus Torvalds /** 13431da177e4SLinus Torvalds * device_release - free device structure. 13441da177e4SLinus Torvalds * @kobj: device's kobject. 13451da177e4SLinus Torvalds * 13461da177e4SLinus Torvalds * This is called once the reference count for the object 13471da177e4SLinus Torvalds * reaches 0. We forward the call to the device's release 13481da177e4SLinus Torvalds * method, which should handle actually freeing the structure. 13491da177e4SLinus Torvalds */ 13501da177e4SLinus Torvalds static void device_release(struct kobject *kobj) 13511da177e4SLinus Torvalds { 1352b0d1f807SLars-Peter Clausen struct device *dev = kobj_to_dev(kobj); 1353fb069a5dSGreg Kroah-Hartman struct device_private *p = dev->p; 13541da177e4SLinus Torvalds 1355a525a3ddSMing Lei /* 1356a525a3ddSMing Lei * Some platform devices are driven without driver attached 1357a525a3ddSMing Lei * and managed resources may have been acquired. Make sure 1358a525a3ddSMing Lei * all resources are released. 1359a525a3ddSMing Lei * 1360a525a3ddSMing Lei * Drivers still can add resources into device after device 1361a525a3ddSMing Lei * is deleted but alive, so release devres here to avoid 1362a525a3ddSMing Lei * possible memory leak. 1363a525a3ddSMing Lei */ 1364a525a3ddSMing Lei devres_release_all(dev); 1365a525a3ddSMing Lei 13661da177e4SLinus Torvalds if (dev->release) 13671da177e4SLinus Torvalds dev->release(dev); 1368f9f852dfSKay Sievers else if (dev->type && dev->type->release) 1369f9f852dfSKay Sievers dev->type->release(dev); 13702620efefSGreg Kroah-Hartman else if (dev->class && dev->class->dev_release) 13712620efefSGreg Kroah-Hartman dev->class->dev_release(dev); 1372f810a5cfSArjan van de Ven else 1373186bddb2SEzequiel Garcia WARN(1, KERN_ERR "Device '%s' does not have a release() function, it is broken and must be fixed. See Documentation/kobject.txt.\n", 13741e0b2cf9SKay Sievers dev_name(dev)); 1375fb069a5dSGreg Kroah-Hartman kfree(p); 13761da177e4SLinus Torvalds } 13771da177e4SLinus Torvalds 1378bc451f20SEric W. Biederman static const void *device_namespace(struct kobject *kobj) 1379bc451f20SEric W. Biederman { 1380b0d1f807SLars-Peter Clausen struct device *dev = kobj_to_dev(kobj); 1381bc451f20SEric W. Biederman const void *ns = NULL; 1382bc451f20SEric W. Biederman 1383bc451f20SEric W. Biederman if (dev->class && dev->class->ns_type) 1384bc451f20SEric W. Biederman ns = dev->class->namespace(dev); 1385bc451f20SEric W. Biederman 1386bc451f20SEric W. Biederman return ns; 1387bc451f20SEric W. Biederman } 1388bc451f20SEric W. Biederman 13899944e894SDmitry Torokhov static void device_get_ownership(struct kobject *kobj, kuid_t *uid, kgid_t *gid) 13909944e894SDmitry Torokhov { 13919944e894SDmitry Torokhov struct device *dev = kobj_to_dev(kobj); 13929944e894SDmitry Torokhov 13939944e894SDmitry Torokhov if (dev->class && dev->class->get_ownership) 13949944e894SDmitry Torokhov dev->class->get_ownership(dev, uid, gid); 13959944e894SDmitry Torokhov } 13969944e894SDmitry Torokhov 13978f4afc41SGreg Kroah-Hartman static struct kobj_type device_ktype = { 13981da177e4SLinus Torvalds .release = device_release, 13991da177e4SLinus Torvalds .sysfs_ops = &dev_sysfs_ops, 1400bc451f20SEric W. Biederman .namespace = device_namespace, 14019944e894SDmitry Torokhov .get_ownership = device_get_ownership, 14021da177e4SLinus Torvalds }; 14031da177e4SLinus Torvalds 14041da177e4SLinus Torvalds 1405312c004dSKay Sievers static int dev_uevent_filter(struct kset *kset, struct kobject *kobj) 14061da177e4SLinus Torvalds { 14071da177e4SLinus Torvalds struct kobj_type *ktype = get_ktype(kobj); 14081da177e4SLinus Torvalds 14098f4afc41SGreg Kroah-Hartman if (ktype == &device_ktype) { 1410b0d1f807SLars-Peter Clausen struct device *dev = kobj_to_dev(kobj); 14111da177e4SLinus Torvalds if (dev->bus) 14121da177e4SLinus Torvalds return 1; 141323681e47SGreg Kroah-Hartman if (dev->class) 141423681e47SGreg Kroah-Hartman return 1; 14151da177e4SLinus Torvalds } 14161da177e4SLinus Torvalds return 0; 14171da177e4SLinus Torvalds } 14181da177e4SLinus Torvalds 1419312c004dSKay Sievers static const char *dev_uevent_name(struct kset *kset, struct kobject *kobj) 14201da177e4SLinus Torvalds { 1421b0d1f807SLars-Peter Clausen struct device *dev = kobj_to_dev(kobj); 14221da177e4SLinus Torvalds 142323681e47SGreg Kroah-Hartman if (dev->bus) 14241da177e4SLinus Torvalds return dev->bus->name; 142523681e47SGreg Kroah-Hartman if (dev->class) 142623681e47SGreg Kroah-Hartman return dev->class->name; 142723681e47SGreg Kroah-Hartman return NULL; 14281da177e4SLinus Torvalds } 14291da177e4SLinus Torvalds 14307eff2e7aSKay Sievers static int dev_uevent(struct kset *kset, struct kobject *kobj, 14317eff2e7aSKay Sievers struct kobj_uevent_env *env) 14321da177e4SLinus Torvalds { 1433b0d1f807SLars-Peter Clausen struct device *dev = kobj_to_dev(kobj); 14341da177e4SLinus Torvalds int retval = 0; 14351da177e4SLinus Torvalds 14366fcf53acSKay Sievers /* add device node properties if present */ 143723681e47SGreg Kroah-Hartman if (MAJOR(dev->devt)) { 14386fcf53acSKay Sievers const char *tmp; 14396fcf53acSKay Sievers const char *name; 14402c9ede55SAl Viro umode_t mode = 0; 14414e4098a3SGreg Kroah-Hartman kuid_t uid = GLOBAL_ROOT_UID; 14424e4098a3SGreg Kroah-Hartman kgid_t gid = GLOBAL_ROOT_GID; 14436fcf53acSKay Sievers 14447eff2e7aSKay Sievers add_uevent_var(env, "MAJOR=%u", MAJOR(dev->devt)); 14457eff2e7aSKay Sievers add_uevent_var(env, "MINOR=%u", MINOR(dev->devt)); 14463c2670e6SKay Sievers name = device_get_devnode(dev, &mode, &uid, &gid, &tmp); 14476fcf53acSKay Sievers if (name) { 14486fcf53acSKay Sievers add_uevent_var(env, "DEVNAME=%s", name); 1449e454cea2SKay Sievers if (mode) 1450e454cea2SKay Sievers add_uevent_var(env, "DEVMODE=%#o", mode & 0777); 14514e4098a3SGreg Kroah-Hartman if (!uid_eq(uid, GLOBAL_ROOT_UID)) 14524e4098a3SGreg Kroah-Hartman add_uevent_var(env, "DEVUID=%u", from_kuid(&init_user_ns, uid)); 14534e4098a3SGreg Kroah-Hartman if (!gid_eq(gid, GLOBAL_ROOT_GID)) 14544e4098a3SGreg Kroah-Hartman add_uevent_var(env, "DEVGID=%u", from_kgid(&init_user_ns, gid)); 14553c2670e6SKay Sievers kfree(tmp); 14566fcf53acSKay Sievers } 145723681e47SGreg Kroah-Hartman } 145823681e47SGreg Kroah-Hartman 1459414264f9SKay Sievers if (dev->type && dev->type->name) 14607eff2e7aSKay Sievers add_uevent_var(env, "DEVTYPE=%s", dev->type->name); 1461414264f9SKay Sievers 1462239378f1SKay Sievers if (dev->driver) 14637eff2e7aSKay Sievers add_uevent_var(env, "DRIVER=%s", dev->driver->name); 1464239378f1SKay Sievers 146507d57a32SGrant Likely /* Add common DT information about the device */ 146607d57a32SGrant Likely of_device_uevent(dev, env); 146707d57a32SGrant Likely 14681da177e4SLinus Torvalds /* have the bus specific function add its stuff */ 14697eff2e7aSKay Sievers if (dev->bus && dev->bus->uevent) { 14707eff2e7aSKay Sievers retval = dev->bus->uevent(dev, env); 1471f9f852dfSKay Sievers if (retval) 14727dc72b28SGreg Kroah-Hartman pr_debug("device: '%s': %s: bus uevent() returned %d\n", 14731e0b2cf9SKay Sievers dev_name(dev), __func__, retval); 14741da177e4SLinus Torvalds } 14751da177e4SLinus Torvalds 14762620efefSGreg Kroah-Hartman /* have the class specific function add its stuff */ 14777eff2e7aSKay Sievers if (dev->class && dev->class->dev_uevent) { 14787eff2e7aSKay Sievers retval = dev->class->dev_uevent(dev, env); 1479f9f852dfSKay Sievers if (retval) 14807dc72b28SGreg Kroah-Hartman pr_debug("device: '%s': %s: class uevent() " 14811e0b2cf9SKay Sievers "returned %d\n", dev_name(dev), 14822b3a302aSHarvey Harrison __func__, retval); 14832620efefSGreg Kroah-Hartman } 1484f9f852dfSKay Sievers 1485eef35c2dSStefan Weil /* have the device type specific function add its stuff */ 14867eff2e7aSKay Sievers if (dev->type && dev->type->uevent) { 14877eff2e7aSKay Sievers retval = dev->type->uevent(dev, env); 1488f9f852dfSKay Sievers if (retval) 14897dc72b28SGreg Kroah-Hartman pr_debug("device: '%s': %s: dev_type uevent() " 14901e0b2cf9SKay Sievers "returned %d\n", dev_name(dev), 14912b3a302aSHarvey Harrison __func__, retval); 14922620efefSGreg Kroah-Hartman } 14932620efefSGreg Kroah-Hartman 14941da177e4SLinus Torvalds return retval; 14951da177e4SLinus Torvalds } 14961da177e4SLinus Torvalds 14979cd43611SEmese Revfy static const struct kset_uevent_ops device_uevent_ops = { 1498312c004dSKay Sievers .filter = dev_uevent_filter, 1499312c004dSKay Sievers .name = dev_uevent_name, 1500312c004dSKay Sievers .uevent = dev_uevent, 15011da177e4SLinus Torvalds }; 15021da177e4SLinus Torvalds 1503c5e064a6SGreg Kroah-Hartman static ssize_t uevent_show(struct device *dev, struct device_attribute *attr, 150416574dccSKay Sievers char *buf) 150516574dccSKay Sievers { 150616574dccSKay Sievers struct kobject *top_kobj; 150716574dccSKay Sievers struct kset *kset; 15087eff2e7aSKay Sievers struct kobj_uevent_env *env = NULL; 150916574dccSKay Sievers int i; 151016574dccSKay Sievers size_t count = 0; 151116574dccSKay Sievers int retval; 151216574dccSKay Sievers 151316574dccSKay Sievers /* search the kset, the device belongs to */ 151416574dccSKay Sievers top_kobj = &dev->kobj; 15155c5daf65SKay Sievers while (!top_kobj->kset && top_kobj->parent) 151616574dccSKay Sievers top_kobj = top_kobj->parent; 151716574dccSKay Sievers if (!top_kobj->kset) 151816574dccSKay Sievers goto out; 15195c5daf65SKay Sievers 152016574dccSKay Sievers kset = top_kobj->kset; 152116574dccSKay Sievers if (!kset->uevent_ops || !kset->uevent_ops->uevent) 152216574dccSKay Sievers goto out; 152316574dccSKay Sievers 152416574dccSKay Sievers /* respect filter */ 152516574dccSKay Sievers if (kset->uevent_ops && kset->uevent_ops->filter) 152616574dccSKay Sievers if (!kset->uevent_ops->filter(kset, &dev->kobj)) 152716574dccSKay Sievers goto out; 152816574dccSKay Sievers 15297eff2e7aSKay Sievers env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL); 15307eff2e7aSKay Sievers if (!env) 1531c7308c81SGreg Kroah-Hartman return -ENOMEM; 1532c7308c81SGreg Kroah-Hartman 153316574dccSKay Sievers /* let the kset specific function add its keys */ 15347eff2e7aSKay Sievers retval = kset->uevent_ops->uevent(kset, &dev->kobj, env); 153516574dccSKay Sievers if (retval) 153616574dccSKay Sievers goto out; 153716574dccSKay Sievers 153816574dccSKay Sievers /* copy keys to file */ 15397eff2e7aSKay Sievers for (i = 0; i < env->envp_idx; i++) 15407eff2e7aSKay Sievers count += sprintf(&buf[count], "%s\n", env->envp[i]); 154116574dccSKay Sievers out: 15427eff2e7aSKay Sievers kfree(env); 154316574dccSKay Sievers return count; 154416574dccSKay Sievers } 154516574dccSKay Sievers 1546c5e064a6SGreg Kroah-Hartman static ssize_t uevent_store(struct device *dev, struct device_attribute *attr, 1547a7fd6706SKay Sievers const char *buf, size_t count) 1548a7fd6706SKay Sievers { 1549df44b479SPeter Rajnoha int rc; 1550df44b479SPeter Rajnoha 1551df44b479SPeter Rajnoha rc = kobject_synth_uevent(&dev->kobj, buf, count); 1552df44b479SPeter Rajnoha 1553df44b479SPeter Rajnoha if (rc) { 1554f36776faSPeter Rajnoha dev_err(dev, "uevent: failed to send synthetic uevent\n"); 1555df44b479SPeter Rajnoha return rc; 1556df44b479SPeter Rajnoha } 155760a96a59SKay Sievers 1558a7fd6706SKay Sievers return count; 1559a7fd6706SKay Sievers } 1560c5e064a6SGreg Kroah-Hartman static DEVICE_ATTR_RW(uevent); 1561a7fd6706SKay Sievers 1562c5e064a6SGreg Kroah-Hartman static ssize_t online_show(struct device *dev, struct device_attribute *attr, 15634f3549d7SRafael J. Wysocki char *buf) 15644f3549d7SRafael J. Wysocki { 15654f3549d7SRafael J. Wysocki bool val; 15664f3549d7SRafael J. Wysocki 15675e33bc41SRafael J. Wysocki device_lock(dev); 15684f3549d7SRafael J. Wysocki val = !dev->offline; 15695e33bc41SRafael J. Wysocki device_unlock(dev); 15704f3549d7SRafael J. Wysocki return sprintf(buf, "%u\n", val); 15714f3549d7SRafael J. Wysocki } 15724f3549d7SRafael J. Wysocki 1573c5e064a6SGreg Kroah-Hartman static ssize_t online_store(struct device *dev, struct device_attribute *attr, 15744f3549d7SRafael J. Wysocki const char *buf, size_t count) 15754f3549d7SRafael J. Wysocki { 15764f3549d7SRafael J. Wysocki bool val; 15774f3549d7SRafael J. Wysocki int ret; 15784f3549d7SRafael J. Wysocki 15794f3549d7SRafael J. Wysocki ret = strtobool(buf, &val); 15804f3549d7SRafael J. Wysocki if (ret < 0) 15814f3549d7SRafael J. Wysocki return ret; 15824f3549d7SRafael J. Wysocki 15835e33bc41SRafael J. Wysocki ret = lock_device_hotplug_sysfs(); 15845e33bc41SRafael J. Wysocki if (ret) 15855e33bc41SRafael J. Wysocki return ret; 15865e33bc41SRafael J. Wysocki 15874f3549d7SRafael J. Wysocki ret = val ? device_online(dev) : device_offline(dev); 15884f3549d7SRafael J. Wysocki unlock_device_hotplug(); 15894f3549d7SRafael J. Wysocki return ret < 0 ? ret : count; 15904f3549d7SRafael J. Wysocki } 1591c5e064a6SGreg Kroah-Hartman static DEVICE_ATTR_RW(online); 15924f3549d7SRafael J. Wysocki 1593fa6fdb33SGreg Kroah-Hartman int device_add_groups(struct device *dev, const struct attribute_group **groups) 1594621a1672SDmitry Torokhov { 15953e9b2baeSGreg Kroah-Hartman return sysfs_create_groups(&dev->kobj, groups); 1596621a1672SDmitry Torokhov } 1597a7670d42SDmitry Torokhov EXPORT_SYMBOL_GPL(device_add_groups); 1598621a1672SDmitry Torokhov 1599fa6fdb33SGreg Kroah-Hartman void device_remove_groups(struct device *dev, 1600a4dbd674SDavid Brownell const struct attribute_group **groups) 1601621a1672SDmitry Torokhov { 16023e9b2baeSGreg Kroah-Hartman sysfs_remove_groups(&dev->kobj, groups); 1603621a1672SDmitry Torokhov } 1604a7670d42SDmitry Torokhov EXPORT_SYMBOL_GPL(device_remove_groups); 1605de0ff00dSGreg Kroah-Hartman 160657b8ff07SDmitry Torokhov union device_attr_group_devres { 160757b8ff07SDmitry Torokhov const struct attribute_group *group; 160857b8ff07SDmitry Torokhov const struct attribute_group **groups; 160957b8ff07SDmitry Torokhov }; 161057b8ff07SDmitry Torokhov 161157b8ff07SDmitry Torokhov static int devm_attr_group_match(struct device *dev, void *res, void *data) 161257b8ff07SDmitry Torokhov { 161357b8ff07SDmitry Torokhov return ((union device_attr_group_devres *)res)->group == data; 161457b8ff07SDmitry Torokhov } 161557b8ff07SDmitry Torokhov 161657b8ff07SDmitry Torokhov static void devm_attr_group_remove(struct device *dev, void *res) 161757b8ff07SDmitry Torokhov { 161857b8ff07SDmitry Torokhov union device_attr_group_devres *devres = res; 161957b8ff07SDmitry Torokhov const struct attribute_group *group = devres->group; 162057b8ff07SDmitry Torokhov 162157b8ff07SDmitry Torokhov dev_dbg(dev, "%s: removing group %p\n", __func__, group); 162257b8ff07SDmitry Torokhov sysfs_remove_group(&dev->kobj, group); 162357b8ff07SDmitry Torokhov } 162457b8ff07SDmitry Torokhov 162557b8ff07SDmitry Torokhov static void devm_attr_groups_remove(struct device *dev, void *res) 162657b8ff07SDmitry Torokhov { 162757b8ff07SDmitry Torokhov union device_attr_group_devres *devres = res; 162857b8ff07SDmitry Torokhov const struct attribute_group **groups = devres->groups; 162957b8ff07SDmitry Torokhov 163057b8ff07SDmitry Torokhov dev_dbg(dev, "%s: removing groups %p\n", __func__, groups); 163157b8ff07SDmitry Torokhov sysfs_remove_groups(&dev->kobj, groups); 163257b8ff07SDmitry Torokhov } 163357b8ff07SDmitry Torokhov 163457b8ff07SDmitry Torokhov /** 163557b8ff07SDmitry Torokhov * devm_device_add_group - given a device, create a managed attribute group 163657b8ff07SDmitry Torokhov * @dev: The device to create the group for 163757b8ff07SDmitry Torokhov * @grp: The attribute group to create 163857b8ff07SDmitry Torokhov * 163957b8ff07SDmitry Torokhov * This function creates a group for the first time. It will explicitly 164057b8ff07SDmitry Torokhov * warn and error if any of the attribute files being created already exist. 164157b8ff07SDmitry Torokhov * 164257b8ff07SDmitry Torokhov * Returns 0 on success or error code on failure. 164357b8ff07SDmitry Torokhov */ 164457b8ff07SDmitry Torokhov int devm_device_add_group(struct device *dev, const struct attribute_group *grp) 164557b8ff07SDmitry Torokhov { 164657b8ff07SDmitry Torokhov union device_attr_group_devres *devres; 164757b8ff07SDmitry Torokhov int error; 164857b8ff07SDmitry Torokhov 164957b8ff07SDmitry Torokhov devres = devres_alloc(devm_attr_group_remove, 165057b8ff07SDmitry Torokhov sizeof(*devres), GFP_KERNEL); 165157b8ff07SDmitry Torokhov if (!devres) 165257b8ff07SDmitry Torokhov return -ENOMEM; 165357b8ff07SDmitry Torokhov 165457b8ff07SDmitry Torokhov error = sysfs_create_group(&dev->kobj, grp); 165557b8ff07SDmitry Torokhov if (error) { 165657b8ff07SDmitry Torokhov devres_free(devres); 165757b8ff07SDmitry Torokhov return error; 165857b8ff07SDmitry Torokhov } 165957b8ff07SDmitry Torokhov 166057b8ff07SDmitry Torokhov devres->group = grp; 166157b8ff07SDmitry Torokhov devres_add(dev, devres); 166257b8ff07SDmitry Torokhov return 0; 166357b8ff07SDmitry Torokhov } 166457b8ff07SDmitry Torokhov EXPORT_SYMBOL_GPL(devm_device_add_group); 166557b8ff07SDmitry Torokhov 166657b8ff07SDmitry Torokhov /** 166757b8ff07SDmitry Torokhov * devm_device_remove_group: remove a managed group from a device 166857b8ff07SDmitry Torokhov * @dev: device to remove the group from 166957b8ff07SDmitry Torokhov * @grp: group to remove 167057b8ff07SDmitry Torokhov * 167157b8ff07SDmitry Torokhov * This function removes a group of attributes from a device. The attributes 167257b8ff07SDmitry Torokhov * previously have to have been created for this group, otherwise it will fail. 167357b8ff07SDmitry Torokhov */ 167457b8ff07SDmitry Torokhov void devm_device_remove_group(struct device *dev, 167557b8ff07SDmitry Torokhov const struct attribute_group *grp) 167657b8ff07SDmitry Torokhov { 167757b8ff07SDmitry Torokhov WARN_ON(devres_release(dev, devm_attr_group_remove, 167857b8ff07SDmitry Torokhov devm_attr_group_match, 167957b8ff07SDmitry Torokhov /* cast away const */ (void *)grp)); 168057b8ff07SDmitry Torokhov } 168157b8ff07SDmitry Torokhov EXPORT_SYMBOL_GPL(devm_device_remove_group); 168257b8ff07SDmitry Torokhov 168357b8ff07SDmitry Torokhov /** 168457b8ff07SDmitry Torokhov * devm_device_add_groups - create a bunch of managed attribute groups 168557b8ff07SDmitry Torokhov * @dev: The device to create the group for 168657b8ff07SDmitry Torokhov * @groups: The attribute groups to create, NULL terminated 168757b8ff07SDmitry Torokhov * 168857b8ff07SDmitry Torokhov * This function creates a bunch of managed attribute groups. If an error 168957b8ff07SDmitry Torokhov * occurs when creating a group, all previously created groups will be 169057b8ff07SDmitry Torokhov * removed, unwinding everything back to the original state when this 169157b8ff07SDmitry Torokhov * function was called. It will explicitly warn and error if any of the 169257b8ff07SDmitry Torokhov * attribute files being created already exist. 169357b8ff07SDmitry Torokhov * 169457b8ff07SDmitry Torokhov * Returns 0 on success or error code from sysfs_create_group on failure. 169557b8ff07SDmitry Torokhov */ 169657b8ff07SDmitry Torokhov int devm_device_add_groups(struct device *dev, 169757b8ff07SDmitry Torokhov const struct attribute_group **groups) 169857b8ff07SDmitry Torokhov { 169957b8ff07SDmitry Torokhov union device_attr_group_devres *devres; 170057b8ff07SDmitry Torokhov int error; 170157b8ff07SDmitry Torokhov 170257b8ff07SDmitry Torokhov devres = devres_alloc(devm_attr_groups_remove, 170357b8ff07SDmitry Torokhov sizeof(*devres), GFP_KERNEL); 170457b8ff07SDmitry Torokhov if (!devres) 170557b8ff07SDmitry Torokhov return -ENOMEM; 170657b8ff07SDmitry Torokhov 170757b8ff07SDmitry Torokhov error = sysfs_create_groups(&dev->kobj, groups); 170857b8ff07SDmitry Torokhov if (error) { 170957b8ff07SDmitry Torokhov devres_free(devres); 171057b8ff07SDmitry Torokhov return error; 171157b8ff07SDmitry Torokhov } 171257b8ff07SDmitry Torokhov 171357b8ff07SDmitry Torokhov devres->groups = groups; 171457b8ff07SDmitry Torokhov devres_add(dev, devres); 171557b8ff07SDmitry Torokhov return 0; 171657b8ff07SDmitry Torokhov } 171757b8ff07SDmitry Torokhov EXPORT_SYMBOL_GPL(devm_device_add_groups); 171857b8ff07SDmitry Torokhov 171957b8ff07SDmitry Torokhov /** 172057b8ff07SDmitry Torokhov * devm_device_remove_groups - remove a list of managed groups 172157b8ff07SDmitry Torokhov * 172257b8ff07SDmitry Torokhov * @dev: The device for the groups to be removed from 172357b8ff07SDmitry Torokhov * @groups: NULL terminated list of groups to be removed 172457b8ff07SDmitry Torokhov * 172557b8ff07SDmitry Torokhov * If groups is not NULL, remove the specified groups from the device. 172657b8ff07SDmitry Torokhov */ 172757b8ff07SDmitry Torokhov void devm_device_remove_groups(struct device *dev, 172857b8ff07SDmitry Torokhov const struct attribute_group **groups) 172957b8ff07SDmitry Torokhov { 173057b8ff07SDmitry Torokhov WARN_ON(devres_release(dev, devm_attr_groups_remove, 173157b8ff07SDmitry Torokhov devm_attr_group_match, 173257b8ff07SDmitry Torokhov /* cast away const */ (void *)groups)); 173357b8ff07SDmitry Torokhov } 173457b8ff07SDmitry Torokhov EXPORT_SYMBOL_GPL(devm_device_remove_groups); 17351da177e4SLinus Torvalds 17362620efefSGreg Kroah-Hartman static int device_add_attrs(struct device *dev) 17372620efefSGreg Kroah-Hartman { 17382620efefSGreg Kroah-Hartman struct class *class = dev->class; 1739aed65af1SStephen Hemminger const struct device_type *type = dev->type; 1740621a1672SDmitry Torokhov int error; 17412620efefSGreg Kroah-Hartman 1742621a1672SDmitry Torokhov if (class) { 1743d05a6f96SGreg Kroah-Hartman error = device_add_groups(dev, class->dev_groups); 17442620efefSGreg Kroah-Hartman if (error) 1745621a1672SDmitry Torokhov return error; 1746f9f852dfSKay Sievers } 1747f9f852dfSKay Sievers 1748621a1672SDmitry Torokhov if (type) { 1749621a1672SDmitry Torokhov error = device_add_groups(dev, type->groups); 1750f9f852dfSKay Sievers if (error) 1751a6b01dedSGreg Kroah-Hartman goto err_remove_class_groups; 1752f9f852dfSKay Sievers } 1753621a1672SDmitry Torokhov 1754621a1672SDmitry Torokhov error = device_add_groups(dev, dev->groups); 1755f9f852dfSKay Sievers if (error) 1756621a1672SDmitry Torokhov goto err_remove_type_groups; 1757621a1672SDmitry Torokhov 17584f3549d7SRafael J. Wysocki if (device_supports_offline(dev) && !dev->offline_disabled) { 1759c5e064a6SGreg Kroah-Hartman error = device_create_file(dev, &dev_attr_online); 17604f3549d7SRafael J. Wysocki if (error) 1761ecfbf6fdSRafael J. Wysocki goto err_remove_dev_groups; 17624f3549d7SRafael J. Wysocki } 17634f3549d7SRafael J. Wysocki 1764621a1672SDmitry Torokhov return 0; 1765621a1672SDmitry Torokhov 1766ecfbf6fdSRafael J. Wysocki err_remove_dev_groups: 1767ecfbf6fdSRafael J. Wysocki device_remove_groups(dev, dev->groups); 1768621a1672SDmitry Torokhov err_remove_type_groups: 1769621a1672SDmitry Torokhov if (type) 1770621a1672SDmitry Torokhov device_remove_groups(dev, type->groups); 1771d05a6f96SGreg Kroah-Hartman err_remove_class_groups: 1772d05a6f96SGreg Kroah-Hartman if (class) 1773d05a6f96SGreg Kroah-Hartman device_remove_groups(dev, class->dev_groups); 1774f9f852dfSKay Sievers 17752620efefSGreg Kroah-Hartman return error; 17762620efefSGreg Kroah-Hartman } 17772620efefSGreg Kroah-Hartman 17782620efefSGreg Kroah-Hartman static void device_remove_attrs(struct device *dev) 17792620efefSGreg Kroah-Hartman { 17802620efefSGreg Kroah-Hartman struct class *class = dev->class; 1781aed65af1SStephen Hemminger const struct device_type *type = dev->type; 17822620efefSGreg Kroah-Hartman 1783c5e064a6SGreg Kroah-Hartman device_remove_file(dev, &dev_attr_online); 1784621a1672SDmitry Torokhov device_remove_groups(dev, dev->groups); 1785f9f852dfSKay Sievers 1786621a1672SDmitry Torokhov if (type) 1787621a1672SDmitry Torokhov device_remove_groups(dev, type->groups); 1788621a1672SDmitry Torokhov 1789a6b01dedSGreg Kroah-Hartman if (class) 1790d05a6f96SGreg Kroah-Hartman device_remove_groups(dev, class->dev_groups); 1791c97415a7SStefan Achatz } 17922620efefSGreg Kroah-Hartman 1793c5e064a6SGreg Kroah-Hartman static ssize_t dev_show(struct device *dev, struct device_attribute *attr, 179423681e47SGreg Kroah-Hartman char *buf) 179523681e47SGreg Kroah-Hartman { 179623681e47SGreg Kroah-Hartman return print_dev_t(buf, dev->devt); 179723681e47SGreg Kroah-Hartman } 1798c5e064a6SGreg Kroah-Hartman static DEVICE_ATTR_RO(dev); 1799ad6a1e1cSTejun Heo 1800ca22e56dSKay Sievers /* /sys/devices/ */ 1801881c6cfdSGreg Kroah-Hartman struct kset *devices_kset; 18021da177e4SLinus Torvalds 18031da177e4SLinus Torvalds /** 180452cdbdd4SGrygorii Strashko * devices_kset_move_before - Move device in the devices_kset's list. 180552cdbdd4SGrygorii Strashko * @deva: Device to move. 180652cdbdd4SGrygorii Strashko * @devb: Device @deva should come before. 180752cdbdd4SGrygorii Strashko */ 180852cdbdd4SGrygorii Strashko static void devices_kset_move_before(struct device *deva, struct device *devb) 180952cdbdd4SGrygorii Strashko { 181052cdbdd4SGrygorii Strashko if (!devices_kset) 181152cdbdd4SGrygorii Strashko return; 181252cdbdd4SGrygorii Strashko pr_debug("devices_kset: Moving %s before %s\n", 181352cdbdd4SGrygorii Strashko dev_name(deva), dev_name(devb)); 181452cdbdd4SGrygorii Strashko spin_lock(&devices_kset->list_lock); 181552cdbdd4SGrygorii Strashko list_move_tail(&deva->kobj.entry, &devb->kobj.entry); 181652cdbdd4SGrygorii Strashko spin_unlock(&devices_kset->list_lock); 181752cdbdd4SGrygorii Strashko } 181852cdbdd4SGrygorii Strashko 181952cdbdd4SGrygorii Strashko /** 182052cdbdd4SGrygorii Strashko * devices_kset_move_after - Move device in the devices_kset's list. 182152cdbdd4SGrygorii Strashko * @deva: Device to move 182252cdbdd4SGrygorii Strashko * @devb: Device @deva should come after. 182352cdbdd4SGrygorii Strashko */ 182452cdbdd4SGrygorii Strashko static void devices_kset_move_after(struct device *deva, struct device *devb) 182552cdbdd4SGrygorii Strashko { 182652cdbdd4SGrygorii Strashko if (!devices_kset) 182752cdbdd4SGrygorii Strashko return; 182852cdbdd4SGrygorii Strashko pr_debug("devices_kset: Moving %s after %s\n", 182952cdbdd4SGrygorii Strashko dev_name(deva), dev_name(devb)); 183052cdbdd4SGrygorii Strashko spin_lock(&devices_kset->list_lock); 183152cdbdd4SGrygorii Strashko list_move(&deva->kobj.entry, &devb->kobj.entry); 183252cdbdd4SGrygorii Strashko spin_unlock(&devices_kset->list_lock); 183352cdbdd4SGrygorii Strashko } 183452cdbdd4SGrygorii Strashko 183552cdbdd4SGrygorii Strashko /** 183652cdbdd4SGrygorii Strashko * devices_kset_move_last - move the device to the end of devices_kset's list. 183752cdbdd4SGrygorii Strashko * @dev: device to move 183852cdbdd4SGrygorii Strashko */ 183952cdbdd4SGrygorii Strashko void devices_kset_move_last(struct device *dev) 184052cdbdd4SGrygorii Strashko { 184152cdbdd4SGrygorii Strashko if (!devices_kset) 184252cdbdd4SGrygorii Strashko return; 184352cdbdd4SGrygorii Strashko pr_debug("devices_kset: Moving %s to end of list\n", dev_name(dev)); 184452cdbdd4SGrygorii Strashko spin_lock(&devices_kset->list_lock); 184552cdbdd4SGrygorii Strashko list_move_tail(&dev->kobj.entry, &devices_kset->list); 184652cdbdd4SGrygorii Strashko spin_unlock(&devices_kset->list_lock); 184752cdbdd4SGrygorii Strashko } 184852cdbdd4SGrygorii Strashko 184952cdbdd4SGrygorii Strashko /** 18501da177e4SLinus Torvalds * device_create_file - create sysfs attribute file for device. 18511da177e4SLinus Torvalds * @dev: device. 18521da177e4SLinus Torvalds * @attr: device attribute descriptor. 18531da177e4SLinus Torvalds */ 185426579ab7SPhil Carmody int device_create_file(struct device *dev, 185526579ab7SPhil Carmody const struct device_attribute *attr) 18561da177e4SLinus Torvalds { 18571da177e4SLinus Torvalds int error = 0; 18588f46baaaSFelipe Balbi 18598f46baaaSFelipe Balbi if (dev) { 18608f46baaaSFelipe Balbi WARN(((attr->attr.mode & S_IWUGO) && !attr->store), 186197521978Sdyoung@redhat.com "Attribute %s: write permission without 'store'\n", 186297521978Sdyoung@redhat.com attr->attr.name); 18638f46baaaSFelipe Balbi WARN(((attr->attr.mode & S_IRUGO) && !attr->show), 186497521978Sdyoung@redhat.com "Attribute %s: read permission without 'show'\n", 186597521978Sdyoung@redhat.com attr->attr.name); 18661da177e4SLinus Torvalds error = sysfs_create_file(&dev->kobj, &attr->attr); 18678f46baaaSFelipe Balbi } 18688f46baaaSFelipe Balbi 18691da177e4SLinus Torvalds return error; 18701da177e4SLinus Torvalds } 187186df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_create_file); 18721da177e4SLinus Torvalds 18731da177e4SLinus Torvalds /** 18741da177e4SLinus Torvalds * device_remove_file - remove sysfs attribute file. 18751da177e4SLinus Torvalds * @dev: device. 18761da177e4SLinus Torvalds * @attr: device attribute descriptor. 18771da177e4SLinus Torvalds */ 187826579ab7SPhil Carmody void device_remove_file(struct device *dev, 187926579ab7SPhil Carmody const struct device_attribute *attr) 18801da177e4SLinus Torvalds { 18810c98b19fSCornelia Huck if (dev) 18821da177e4SLinus Torvalds sysfs_remove_file(&dev->kobj, &attr->attr); 18831da177e4SLinus Torvalds } 188486df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_remove_file); 18851da177e4SLinus Torvalds 18862589f188SGreg Kroah-Hartman /** 18876b0afc2aSTejun Heo * device_remove_file_self - remove sysfs attribute file from its own method. 18886b0afc2aSTejun Heo * @dev: device. 18896b0afc2aSTejun Heo * @attr: device attribute descriptor. 18906b0afc2aSTejun Heo * 18916b0afc2aSTejun Heo * See kernfs_remove_self() for details. 18926b0afc2aSTejun Heo */ 18936b0afc2aSTejun Heo bool device_remove_file_self(struct device *dev, 18946b0afc2aSTejun Heo const struct device_attribute *attr) 18956b0afc2aSTejun Heo { 18966b0afc2aSTejun Heo if (dev) 18976b0afc2aSTejun Heo return sysfs_remove_file_self(&dev->kobj, &attr->attr); 18986b0afc2aSTejun Heo else 18996b0afc2aSTejun Heo return false; 19006b0afc2aSTejun Heo } 19016b0afc2aSTejun Heo EXPORT_SYMBOL_GPL(device_remove_file_self); 19026b0afc2aSTejun Heo 19036b0afc2aSTejun Heo /** 19042589f188SGreg Kroah-Hartman * device_create_bin_file - create sysfs binary attribute file for device. 19052589f188SGreg Kroah-Hartman * @dev: device. 19062589f188SGreg Kroah-Hartman * @attr: device binary attribute descriptor. 19072589f188SGreg Kroah-Hartman */ 190866ecb92bSPhil Carmody int device_create_bin_file(struct device *dev, 190966ecb92bSPhil Carmody const struct bin_attribute *attr) 19102589f188SGreg Kroah-Hartman { 19112589f188SGreg Kroah-Hartman int error = -EINVAL; 19122589f188SGreg Kroah-Hartman if (dev) 19132589f188SGreg Kroah-Hartman error = sysfs_create_bin_file(&dev->kobj, attr); 19142589f188SGreg Kroah-Hartman return error; 19152589f188SGreg Kroah-Hartman } 19162589f188SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(device_create_bin_file); 19172589f188SGreg Kroah-Hartman 19182589f188SGreg Kroah-Hartman /** 19192589f188SGreg Kroah-Hartman * device_remove_bin_file - remove sysfs binary attribute file 19202589f188SGreg Kroah-Hartman * @dev: device. 19212589f188SGreg Kroah-Hartman * @attr: device binary attribute descriptor. 19222589f188SGreg Kroah-Hartman */ 192366ecb92bSPhil Carmody void device_remove_bin_file(struct device *dev, 192466ecb92bSPhil Carmody const struct bin_attribute *attr) 19252589f188SGreg Kroah-Hartman { 19262589f188SGreg Kroah-Hartman if (dev) 19272589f188SGreg Kroah-Hartman sysfs_remove_bin_file(&dev->kobj, attr); 19282589f188SGreg Kroah-Hartman } 19292589f188SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(device_remove_bin_file); 19302589f188SGreg Kroah-Hartman 193134bb61f9SJames Bottomley static void klist_children_get(struct klist_node *n) 193234bb61f9SJames Bottomley { 1933f791b8c8SGreg Kroah-Hartman struct device_private *p = to_device_private_parent(n); 1934f791b8c8SGreg Kroah-Hartman struct device *dev = p->device; 193534bb61f9SJames Bottomley 193634bb61f9SJames Bottomley get_device(dev); 193734bb61f9SJames Bottomley } 193834bb61f9SJames Bottomley 193934bb61f9SJames Bottomley static void klist_children_put(struct klist_node *n) 194034bb61f9SJames Bottomley { 1941f791b8c8SGreg Kroah-Hartman struct device_private *p = to_device_private_parent(n); 1942f791b8c8SGreg Kroah-Hartman struct device *dev = p->device; 194334bb61f9SJames Bottomley 194434bb61f9SJames Bottomley put_device(dev); 194534bb61f9SJames Bottomley } 194634bb61f9SJames Bottomley 19471da177e4SLinus Torvalds /** 19481da177e4SLinus Torvalds * device_initialize - init device structure. 19491da177e4SLinus Torvalds * @dev: device. 19501da177e4SLinus Torvalds * 19515739411aSCornelia Huck * This prepares the device for use by other layers by initializing 19525739411aSCornelia Huck * its fields. 19531da177e4SLinus Torvalds * It is the first half of device_register(), if called by 19545739411aSCornelia Huck * that function, though it can also be called separately, so one 19555739411aSCornelia Huck * may use @dev's fields. In particular, get_device()/put_device() 19565739411aSCornelia Huck * may be used for reference counting of @dev after calling this 19575739411aSCornelia Huck * function. 19585739411aSCornelia Huck * 1959b10d5efdSAlan Stern * All fields in @dev must be initialized by the caller to 0, except 1960b10d5efdSAlan Stern * for those explicitly set to some other value. The simplest 1961b10d5efdSAlan Stern * approach is to use kzalloc() to allocate the structure containing 1962b10d5efdSAlan Stern * @dev. 1963b10d5efdSAlan Stern * 19645739411aSCornelia Huck * NOTE: Use put_device() to give up your reference instead of freeing 19655739411aSCornelia Huck * @dev directly once you have called this function. 19661da177e4SLinus Torvalds */ 19671da177e4SLinus Torvalds void device_initialize(struct device *dev) 19681da177e4SLinus Torvalds { 1969881c6cfdSGreg Kroah-Hartman dev->kobj.kset = devices_kset; 1970f9cb074bSGreg Kroah-Hartman kobject_init(&dev->kobj, &device_ktype); 19711da177e4SLinus Torvalds INIT_LIST_HEAD(&dev->dma_pools); 19723142788bSThomas Gleixner mutex_init(&dev->mutex); 197387a30e1fSDan Williams #ifdef CONFIG_PROVE_LOCKING 197487a30e1fSDan Williams mutex_init(&dev->lockdep_mutex); 197587a30e1fSDan Williams #endif 19761704f47bSPeter Zijlstra lockdep_set_novalidate_class(&dev->mutex); 19779ac7849eSTejun Heo spin_lock_init(&dev->devres_lock); 19789ac7849eSTejun Heo INIT_LIST_HEAD(&dev->devres_head); 19793b98aeafSAlan Stern device_pm_init(dev); 198087348136SChristoph Hellwig set_dev_node(dev, -1); 19814a7cc831SJiang Liu #ifdef CONFIG_GENERIC_MSI_IRQ 19824a7cc831SJiang Liu INIT_LIST_HEAD(&dev->msi_list); 19834a7cc831SJiang Liu #endif 19849ed98953SRafael J. Wysocki INIT_LIST_HEAD(&dev->links.consumers); 19859ed98953SRafael J. Wysocki INIT_LIST_HEAD(&dev->links.suppliers); 1986e2ae9bccSSaravana Kannan INIT_LIST_HEAD(&dev->links.needs_suppliers); 1987fc5a251dSSaravana Kannan INIT_LIST_HEAD(&dev->links.defer_sync); 19889ed98953SRafael J. Wysocki dev->links.status = DL_DEV_NO_DRIVER; 19891da177e4SLinus Torvalds } 199086df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_initialize); 19911da177e4SLinus Torvalds 1992d73ce004STejun Heo struct kobject *virtual_device_parent(struct device *dev) 1993f0ee61a6SGreg Kroah-Hartman { 1994f0ee61a6SGreg Kroah-Hartman static struct kobject *virtual_dir = NULL; 1995f0ee61a6SGreg Kroah-Hartman 1996f0ee61a6SGreg Kroah-Hartman if (!virtual_dir) 19974ff6abffSGreg Kroah-Hartman virtual_dir = kobject_create_and_add("virtual", 1998881c6cfdSGreg Kroah-Hartman &devices_kset->kobj); 1999f0ee61a6SGreg Kroah-Hartman 200086406245SKay Sievers return virtual_dir; 2001f0ee61a6SGreg Kroah-Hartman } 2002f0ee61a6SGreg Kroah-Hartman 2003bc451f20SEric W. Biederman struct class_dir { 2004bc451f20SEric W. Biederman struct kobject kobj; 2005bc451f20SEric W. Biederman struct class *class; 2006bc451f20SEric W. Biederman }; 2007bc451f20SEric W. Biederman 2008bc451f20SEric W. Biederman #define to_class_dir(obj) container_of(obj, struct class_dir, kobj) 2009bc451f20SEric W. Biederman 2010bc451f20SEric W. Biederman static void class_dir_release(struct kobject *kobj) 2011bc451f20SEric W. Biederman { 2012bc451f20SEric W. Biederman struct class_dir *dir = to_class_dir(kobj); 2013bc451f20SEric W. Biederman kfree(dir); 2014bc451f20SEric W. Biederman } 2015bc451f20SEric W. Biederman 2016bc451f20SEric W. Biederman static const 2017bc451f20SEric W. Biederman struct kobj_ns_type_operations *class_dir_child_ns_type(struct kobject *kobj) 2018bc451f20SEric W. Biederman { 2019bc451f20SEric W. Biederman struct class_dir *dir = to_class_dir(kobj); 2020bc451f20SEric W. Biederman return dir->class->ns_type; 2021bc451f20SEric W. Biederman } 2022bc451f20SEric W. Biederman 2023bc451f20SEric W. Biederman static struct kobj_type class_dir_ktype = { 2024bc451f20SEric W. Biederman .release = class_dir_release, 2025bc451f20SEric W. Biederman .sysfs_ops = &kobj_sysfs_ops, 2026bc451f20SEric W. Biederman .child_ns_type = class_dir_child_ns_type 2027bc451f20SEric W. Biederman }; 2028bc451f20SEric W. Biederman 2029bc451f20SEric W. Biederman static struct kobject * 2030bc451f20SEric W. Biederman class_dir_create_and_add(struct class *class, struct kobject *parent_kobj) 2031bc451f20SEric W. Biederman { 2032bc451f20SEric W. Biederman struct class_dir *dir; 2033bc451f20SEric W. Biederman int retval; 2034bc451f20SEric W. Biederman 2035bc451f20SEric W. Biederman dir = kzalloc(sizeof(*dir), GFP_KERNEL); 2036bc451f20SEric W. Biederman if (!dir) 203784d0c27dSTetsuo Handa return ERR_PTR(-ENOMEM); 2038bc451f20SEric W. Biederman 2039bc451f20SEric W. Biederman dir->class = class; 2040bc451f20SEric W. Biederman kobject_init(&dir->kobj, &class_dir_ktype); 2041bc451f20SEric W. Biederman 20426b6e39a6SKay Sievers dir->kobj.kset = &class->p->glue_dirs; 2043bc451f20SEric W. Biederman 2044bc451f20SEric W. Biederman retval = kobject_add(&dir->kobj, parent_kobj, "%s", class->name); 2045bc451f20SEric W. Biederman if (retval < 0) { 2046bc451f20SEric W. Biederman kobject_put(&dir->kobj); 204784d0c27dSTetsuo Handa return ERR_PTR(retval); 2048bc451f20SEric W. Biederman } 2049bc451f20SEric W. Biederman return &dir->kobj; 2050bc451f20SEric W. Biederman } 2051bc451f20SEric W. Biederman 2052e4a60d13SYijing Wang static DEFINE_MUTEX(gdp_mutex); 2053bc451f20SEric W. Biederman 2054c744aeaeSCornelia Huck static struct kobject *get_device_parent(struct device *dev, 2055c744aeaeSCornelia Huck struct device *parent) 205640fa5422SGreg Kroah-Hartman { 205786406245SKay Sievers if (dev->class) { 205886406245SKay Sievers struct kobject *kobj = NULL; 205986406245SKay Sievers struct kobject *parent_kobj; 206086406245SKay Sievers struct kobject *k; 206186406245SKay Sievers 2062ead454feSRandy Dunlap #ifdef CONFIG_BLOCK 206339aba963SKay Sievers /* block disks show up in /sys/block */ 2064e52eec13SAndi Kleen if (sysfs_deprecated && dev->class == &block_class) { 206539aba963SKay Sievers if (parent && parent->class == &block_class) 206639aba963SKay Sievers return &parent->kobj; 20676b6e39a6SKay Sievers return &block_class.p->subsys.kobj; 206839aba963SKay Sievers } 2069ead454feSRandy Dunlap #endif 2070e52eec13SAndi Kleen 207186406245SKay Sievers /* 207286406245SKay Sievers * If we have no parent, we live in "virtual". 20730f4dafc0SKay Sievers * Class-devices with a non class-device as parent, live 20740f4dafc0SKay Sievers * in a "glue" directory to prevent namespace collisions. 207586406245SKay Sievers */ 207686406245SKay Sievers if (parent == NULL) 207786406245SKay Sievers parent_kobj = virtual_device_parent(dev); 207824b1442dSEric W. Biederman else if (parent->class && !dev->class->ns_type) 207986406245SKay Sievers return &parent->kobj; 208086406245SKay Sievers else 208186406245SKay Sievers parent_kobj = &parent->kobj; 208286406245SKay Sievers 208377d3d7c1STejun Heo mutex_lock(&gdp_mutex); 208477d3d7c1STejun Heo 208586406245SKay Sievers /* find our class-directory at the parent and reference it */ 20866b6e39a6SKay Sievers spin_lock(&dev->class->p->glue_dirs.list_lock); 20876b6e39a6SKay Sievers list_for_each_entry(k, &dev->class->p->glue_dirs.list, entry) 208886406245SKay Sievers if (k->parent == parent_kobj) { 208986406245SKay Sievers kobj = kobject_get(k); 209086406245SKay Sievers break; 209186406245SKay Sievers } 20926b6e39a6SKay Sievers spin_unlock(&dev->class->p->glue_dirs.list_lock); 209377d3d7c1STejun Heo if (kobj) { 209477d3d7c1STejun Heo mutex_unlock(&gdp_mutex); 209586406245SKay Sievers return kobj; 209677d3d7c1STejun Heo } 209786406245SKay Sievers 209886406245SKay Sievers /* or create a new class-directory at the parent device */ 2099bc451f20SEric W. Biederman k = class_dir_create_and_add(dev->class, parent_kobj); 21000f4dafc0SKay Sievers /* do not emit an uevent for this simple "glue" directory */ 210177d3d7c1STejun Heo mutex_unlock(&gdp_mutex); 210243968d2fSGreg Kroah-Hartman return k; 210386406245SKay Sievers } 210486406245SKay Sievers 2105ca22e56dSKay Sievers /* subsystems can specify a default root directory for their devices */ 2106ca22e56dSKay Sievers if (!parent && dev->bus && dev->bus->dev_root) 2107ca22e56dSKay Sievers return &dev->bus->dev_root->kobj; 2108ca22e56dSKay Sievers 210986406245SKay Sievers if (parent) 2110c744aeaeSCornelia Huck return &parent->kobj; 2111c744aeaeSCornelia Huck return NULL; 2112c744aeaeSCornelia Huck } 2113da231fd5SKay Sievers 2114cebf8fd1SMing Lei static inline bool live_in_glue_dir(struct kobject *kobj, 2115cebf8fd1SMing Lei struct device *dev) 2116cebf8fd1SMing Lei { 2117cebf8fd1SMing Lei if (!kobj || !dev->class || 2118cebf8fd1SMing Lei kobj->kset != &dev->class->p->glue_dirs) 2119cebf8fd1SMing Lei return false; 2120cebf8fd1SMing Lei return true; 2121cebf8fd1SMing Lei } 2122cebf8fd1SMing Lei 2123cebf8fd1SMing Lei static inline struct kobject *get_glue_dir(struct device *dev) 2124cebf8fd1SMing Lei { 2125cebf8fd1SMing Lei return dev->kobj.parent; 2126cebf8fd1SMing Lei } 2127cebf8fd1SMing Lei 2128cebf8fd1SMing Lei /* 2129cebf8fd1SMing Lei * make sure cleaning up dir as the last step, we need to make 2130cebf8fd1SMing Lei * sure .release handler of kobject is run with holding the 2131cebf8fd1SMing Lei * global lock 2132cebf8fd1SMing Lei */ 213363b6971aSCornelia Huck static void cleanup_glue_dir(struct device *dev, struct kobject *glue_dir) 2134da231fd5SKay Sievers { 2135ac43432cSMuchun Song unsigned int ref; 2136ac43432cSMuchun Song 21370f4dafc0SKay Sievers /* see if we live in a "glue" directory */ 2138cebf8fd1SMing Lei if (!live_in_glue_dir(glue_dir, dev)) 2139da231fd5SKay Sievers return; 2140da231fd5SKay Sievers 2141e4a60d13SYijing Wang mutex_lock(&gdp_mutex); 2142ac43432cSMuchun Song /** 2143ac43432cSMuchun Song * There is a race condition between removing glue directory 2144ac43432cSMuchun Song * and adding a new device under the glue directory. 2145ac43432cSMuchun Song * 2146ac43432cSMuchun Song * CPU1: CPU2: 2147ac43432cSMuchun Song * 2148ac43432cSMuchun Song * device_add() 2149ac43432cSMuchun Song * get_device_parent() 2150ac43432cSMuchun Song * class_dir_create_and_add() 2151ac43432cSMuchun Song * kobject_add_internal() 2152ac43432cSMuchun Song * create_dir() // create glue_dir 2153ac43432cSMuchun Song * 2154ac43432cSMuchun Song * device_add() 2155ac43432cSMuchun Song * get_device_parent() 2156ac43432cSMuchun Song * kobject_get() // get glue_dir 2157ac43432cSMuchun Song * 2158ac43432cSMuchun Song * device_del() 2159ac43432cSMuchun Song * cleanup_glue_dir() 2160ac43432cSMuchun Song * kobject_del(glue_dir) 2161ac43432cSMuchun Song * 2162ac43432cSMuchun Song * kobject_add() 2163ac43432cSMuchun Song * kobject_add_internal() 2164ac43432cSMuchun Song * create_dir() // in glue_dir 2165ac43432cSMuchun Song * sysfs_create_dir_ns() 2166ac43432cSMuchun Song * kernfs_create_dir_ns(sd) 2167ac43432cSMuchun Song * 2168ac43432cSMuchun Song * sysfs_remove_dir() // glue_dir->sd=NULL 2169ac43432cSMuchun Song * sysfs_put() // free glue_dir->sd 2170ac43432cSMuchun Song * 2171ac43432cSMuchun Song * // sd is freed 2172ac43432cSMuchun Song * kernfs_new_node(sd) 2173ac43432cSMuchun Song * kernfs_get(glue_dir) 2174ac43432cSMuchun Song * kernfs_add_one() 2175ac43432cSMuchun Song * kernfs_put() 2176ac43432cSMuchun Song * 2177ac43432cSMuchun Song * Before CPU1 remove last child device under glue dir, if CPU2 add 2178ac43432cSMuchun Song * a new device under glue dir, the glue_dir kobject reference count 2179ac43432cSMuchun Song * will be increase to 2 in kobject_get(k). And CPU2 has been called 2180ac43432cSMuchun Song * kernfs_create_dir_ns(). Meanwhile, CPU1 call sysfs_remove_dir() 2181ac43432cSMuchun Song * and sysfs_put(). This result in glue_dir->sd is freed. 2182ac43432cSMuchun Song * 2183ac43432cSMuchun Song * Then the CPU2 will see a stale "empty" but still potentially used 2184ac43432cSMuchun Song * glue dir around in kernfs_new_node(). 2185ac43432cSMuchun Song * 2186ac43432cSMuchun Song * In order to avoid this happening, we also should make sure that 2187ac43432cSMuchun Song * kernfs_node for glue_dir is released in CPU1 only when refcount 2188ac43432cSMuchun Song * for glue_dir kobj is 1. 2189ac43432cSMuchun Song */ 2190ac43432cSMuchun Song ref = kref_read(&glue_dir->kref); 2191ac43432cSMuchun Song if (!kobject_has_children(glue_dir) && !--ref) 2192726e4109SBenjamin Herrenschmidt kobject_del(glue_dir); 21930f4dafc0SKay Sievers kobject_put(glue_dir); 2194e4a60d13SYijing Wang mutex_unlock(&gdp_mutex); 2195da231fd5SKay Sievers } 219663b6971aSCornelia Huck 21972ee97cafSCornelia Huck static int device_add_class_symlinks(struct device *dev) 21982ee97cafSCornelia Huck { 21995590f319SBenjamin Herrenschmidt struct device_node *of_node = dev_of_node(dev); 22002ee97cafSCornelia Huck int error; 22012ee97cafSCornelia Huck 22025590f319SBenjamin Herrenschmidt if (of_node) { 22030c3c234bSRob Herring error = sysfs_create_link(&dev->kobj, of_node_kobj(of_node), "of_node"); 22045590f319SBenjamin Herrenschmidt if (error) 22055590f319SBenjamin Herrenschmidt dev_warn(dev, "Error %d creating of_node link\n",error); 22065590f319SBenjamin Herrenschmidt /* An error here doesn't warrant bringing down the device */ 22075590f319SBenjamin Herrenschmidt } 22085590f319SBenjamin Herrenschmidt 22092ee97cafSCornelia Huck if (!dev->class) 22102ee97cafSCornelia Huck return 0; 2211da231fd5SKay Sievers 22121fbfee6cSGreg Kroah-Hartman error = sysfs_create_link(&dev->kobj, 22136b6e39a6SKay Sievers &dev->class->p->subsys.kobj, 22142ee97cafSCornelia Huck "subsystem"); 22152ee97cafSCornelia Huck if (error) 22165590f319SBenjamin Herrenschmidt goto out_devnode; 2217da231fd5SKay Sievers 22184e886c29SGreg Kroah-Hartman if (dev->parent && device_is_not_partition(dev)) { 22194f01a757SDmitry Torokhov error = sysfs_create_link(&dev->kobj, &dev->parent->kobj, 22204f01a757SDmitry Torokhov "device"); 22214f01a757SDmitry Torokhov if (error) 222239aba963SKay Sievers goto out_subsys; 22232ee97cafSCornelia Huck } 222439aba963SKay Sievers 2225ead454feSRandy Dunlap #ifdef CONFIG_BLOCK 222639aba963SKay Sievers /* /sys/block has directories and does not need symlinks */ 2227e52eec13SAndi Kleen if (sysfs_deprecated && dev->class == &block_class) 222839aba963SKay Sievers return 0; 2229ead454feSRandy Dunlap #endif 223039aba963SKay Sievers 223139aba963SKay Sievers /* link in the class directory pointing to the device */ 22326b6e39a6SKay Sievers error = sysfs_create_link(&dev->class->p->subsys.kobj, 223339aba963SKay Sievers &dev->kobj, dev_name(dev)); 223439aba963SKay Sievers if (error) 223539aba963SKay Sievers goto out_device; 223639aba963SKay Sievers 22372ee97cafSCornelia Huck return 0; 22382ee97cafSCornelia Huck 223939aba963SKay Sievers out_device: 224039aba963SKay Sievers sysfs_remove_link(&dev->kobj, "device"); 2241da231fd5SKay Sievers 22422ee97cafSCornelia Huck out_subsys: 22432ee97cafSCornelia Huck sysfs_remove_link(&dev->kobj, "subsystem"); 22445590f319SBenjamin Herrenschmidt out_devnode: 22455590f319SBenjamin Herrenschmidt sysfs_remove_link(&dev->kobj, "of_node"); 22462ee97cafSCornelia Huck return error; 22472ee97cafSCornelia Huck } 22482ee97cafSCornelia Huck 22492ee97cafSCornelia Huck static void device_remove_class_symlinks(struct device *dev) 22502ee97cafSCornelia Huck { 22515590f319SBenjamin Herrenschmidt if (dev_of_node(dev)) 22525590f319SBenjamin Herrenschmidt sysfs_remove_link(&dev->kobj, "of_node"); 22535590f319SBenjamin Herrenschmidt 22542ee97cafSCornelia Huck if (!dev->class) 22552ee97cafSCornelia Huck return; 2256da231fd5SKay Sievers 22574e886c29SGreg Kroah-Hartman if (dev->parent && device_is_not_partition(dev)) 2258da231fd5SKay Sievers sysfs_remove_link(&dev->kobj, "device"); 22592ee97cafSCornelia Huck sysfs_remove_link(&dev->kobj, "subsystem"); 2260ead454feSRandy Dunlap #ifdef CONFIG_BLOCK 2261e52eec13SAndi Kleen if (sysfs_deprecated && dev->class == &block_class) 226239aba963SKay Sievers return; 2263ead454feSRandy Dunlap #endif 22646b6e39a6SKay Sievers sysfs_delete_link(&dev->class->p->subsys.kobj, &dev->kobj, dev_name(dev)); 22652ee97cafSCornelia Huck } 22662ee97cafSCornelia Huck 22671da177e4SLinus Torvalds /** 2268413c239fSStephen Rothwell * dev_set_name - set a device name 2269413c239fSStephen Rothwell * @dev: device 227046232366SRandy Dunlap * @fmt: format string for the device's name 2271413c239fSStephen Rothwell */ 2272413c239fSStephen Rothwell int dev_set_name(struct device *dev, const char *fmt, ...) 2273413c239fSStephen Rothwell { 2274413c239fSStephen Rothwell va_list vargs; 22751fa5ae85SKay Sievers int err; 2276413c239fSStephen Rothwell 2277413c239fSStephen Rothwell va_start(vargs, fmt); 22781fa5ae85SKay Sievers err = kobject_set_name_vargs(&dev->kobj, fmt, vargs); 2279413c239fSStephen Rothwell va_end(vargs); 22801fa5ae85SKay Sievers return err; 2281413c239fSStephen Rothwell } 2282413c239fSStephen Rothwell EXPORT_SYMBOL_GPL(dev_set_name); 2283413c239fSStephen Rothwell 2284413c239fSStephen Rothwell /** 2285e105b8bfSDan Williams * device_to_dev_kobj - select a /sys/dev/ directory for the device 2286e105b8bfSDan Williams * @dev: device 2287e105b8bfSDan Williams * 2288e105b8bfSDan Williams * By default we select char/ for new entries. Setting class->dev_obj 2289e105b8bfSDan Williams * to NULL prevents an entry from being created. class->dev_kobj must 2290e105b8bfSDan Williams * be set (or cleared) before any devices are registered to the class 2291e105b8bfSDan Williams * otherwise device_create_sys_dev_entry() and 22920d4e293cSPeter Korsgaard * device_remove_sys_dev_entry() will disagree about the presence of 22930d4e293cSPeter Korsgaard * the link. 2294e105b8bfSDan Williams */ 2295e105b8bfSDan Williams static struct kobject *device_to_dev_kobj(struct device *dev) 2296e105b8bfSDan Williams { 2297e105b8bfSDan Williams struct kobject *kobj; 2298e105b8bfSDan Williams 2299e105b8bfSDan Williams if (dev->class) 2300e105b8bfSDan Williams kobj = dev->class->dev_kobj; 2301e105b8bfSDan Williams else 2302e105b8bfSDan Williams kobj = sysfs_dev_char_kobj; 2303e105b8bfSDan Williams 2304e105b8bfSDan Williams return kobj; 2305e105b8bfSDan Williams } 2306e105b8bfSDan Williams 2307e105b8bfSDan Williams static int device_create_sys_dev_entry(struct device *dev) 2308e105b8bfSDan Williams { 2309e105b8bfSDan Williams struct kobject *kobj = device_to_dev_kobj(dev); 2310e105b8bfSDan Williams int error = 0; 2311e105b8bfSDan Williams char devt_str[15]; 2312e105b8bfSDan Williams 2313e105b8bfSDan Williams if (kobj) { 2314e105b8bfSDan Williams format_dev_t(devt_str, dev->devt); 2315e105b8bfSDan Williams error = sysfs_create_link(kobj, &dev->kobj, devt_str); 2316e105b8bfSDan Williams } 2317e105b8bfSDan Williams 2318e105b8bfSDan Williams return error; 2319e105b8bfSDan Williams } 2320e105b8bfSDan Williams 2321e105b8bfSDan Williams static void device_remove_sys_dev_entry(struct device *dev) 2322e105b8bfSDan Williams { 2323e105b8bfSDan Williams struct kobject *kobj = device_to_dev_kobj(dev); 2324e105b8bfSDan Williams char devt_str[15]; 2325e105b8bfSDan Williams 2326e105b8bfSDan Williams if (kobj) { 2327e105b8bfSDan Williams format_dev_t(devt_str, dev->devt); 2328e105b8bfSDan Williams sysfs_remove_link(kobj, devt_str); 2329e105b8bfSDan Williams } 2330e105b8bfSDan Williams } 2331e105b8bfSDan Williams 233246d3a037SShaokun Zhang static int device_private_init(struct device *dev) 2333b4028437SGreg Kroah-Hartman { 2334b4028437SGreg Kroah-Hartman dev->p = kzalloc(sizeof(*dev->p), GFP_KERNEL); 2335b4028437SGreg Kroah-Hartman if (!dev->p) 2336b4028437SGreg Kroah-Hartman return -ENOMEM; 2337b4028437SGreg Kroah-Hartman dev->p->device = dev; 2338b4028437SGreg Kroah-Hartman klist_init(&dev->p->klist_children, klist_children_get, 2339b4028437SGreg Kroah-Hartman klist_children_put); 2340ef8a3fd6SGreg Kroah-Hartman INIT_LIST_HEAD(&dev->p->deferred_probe); 2341b4028437SGreg Kroah-Hartman return 0; 2342b4028437SGreg Kroah-Hartman } 2343b4028437SGreg Kroah-Hartman 2344e105b8bfSDan Williams /** 23451da177e4SLinus Torvalds * device_add - add device to device hierarchy. 23461da177e4SLinus Torvalds * @dev: device. 23471da177e4SLinus Torvalds * 23481da177e4SLinus Torvalds * This is part 2 of device_register(), though may be called 23491da177e4SLinus Torvalds * separately _iff_ device_initialize() has been called separately. 23501da177e4SLinus Torvalds * 23515739411aSCornelia Huck * This adds @dev to the kobject hierarchy via kobject_add(), adds it 23521da177e4SLinus Torvalds * to the global and sibling lists for the device, then 23531da177e4SLinus Torvalds * adds it to the other relevant subsystems of the driver model. 23545739411aSCornelia Huck * 2355b10d5efdSAlan Stern * Do not call this routine or device_register() more than once for 2356b10d5efdSAlan Stern * any device structure. The driver model core is not designed to work 2357b10d5efdSAlan Stern * with devices that get unregistered and then spring back to life. 2358b10d5efdSAlan Stern * (Among other things, it's very hard to guarantee that all references 2359b10d5efdSAlan Stern * to the previous incarnation of @dev have been dropped.) Allocate 2360b10d5efdSAlan Stern * and register a fresh new struct device instead. 2361b10d5efdSAlan Stern * 23625739411aSCornelia Huck * NOTE: _Never_ directly free @dev after calling this function, even 23635739411aSCornelia Huck * if it returned an error! Always use put_device() to give up your 23645739411aSCornelia Huck * reference instead. 2365affada72SBorislav Petkov * 2366affada72SBorislav Petkov * Rule of thumb is: if device_add() succeeds, you should call 2367affada72SBorislav Petkov * device_del() when you want to get rid of it. If device_add() has 2368affada72SBorislav Petkov * *not* succeeded, use *only* put_device() to drop the reference 2369affada72SBorislav Petkov * count. 23701da177e4SLinus Torvalds */ 23711da177e4SLinus Torvalds int device_add(struct device *dev) 23721da177e4SLinus Torvalds { 237335dbf4efSViresh Kumar struct device *parent; 2374ca22e56dSKay Sievers struct kobject *kobj; 2375c47ed219SGreg Kroah-Hartman struct class_interface *class_intf; 237603324507SSaravana Kannan int error = -EINVAL, fw_ret; 2377cebf8fd1SMing Lei struct kobject *glue_dir = NULL; 2378775b64d2SRafael J. Wysocki 23791da177e4SLinus Torvalds dev = get_device(dev); 2380c906a48aSGreg Kroah-Hartman if (!dev) 2381c906a48aSGreg Kroah-Hartman goto done; 2382c906a48aSGreg Kroah-Hartman 2383fb069a5dSGreg Kroah-Hartman if (!dev->p) { 2384b4028437SGreg Kroah-Hartman error = device_private_init(dev); 2385b4028437SGreg Kroah-Hartman if (error) 2386fb069a5dSGreg Kroah-Hartman goto done; 2387fb069a5dSGreg Kroah-Hartman } 2388fb069a5dSGreg Kroah-Hartman 23891fa5ae85SKay Sievers /* 23901fa5ae85SKay Sievers * for statically allocated devices, which should all be converted 23911fa5ae85SKay Sievers * some day, we need to initialize the name. We prevent reading back 23921fa5ae85SKay Sievers * the name, and force the use of dev_name() 23931fa5ae85SKay Sievers */ 23941fa5ae85SKay Sievers if (dev->init_name) { 2395acc0e90fSGreg Kroah-Hartman dev_set_name(dev, "%s", dev->init_name); 23961fa5ae85SKay Sievers dev->init_name = NULL; 23971fa5ae85SKay Sievers } 2398c906a48aSGreg Kroah-Hartman 2399ca22e56dSKay Sievers /* subsystems can specify simple device enumeration */ 2400ca22e56dSKay Sievers if (!dev_name(dev) && dev->bus && dev->bus->dev_name) 2401ca22e56dSKay Sievers dev_set_name(dev, "%s%u", dev->bus->dev_name, dev->id); 2402ca22e56dSKay Sievers 2403e6309e75SThomas Gleixner if (!dev_name(dev)) { 2404e6309e75SThomas Gleixner error = -EINVAL; 24055c8563d7SKay Sievers goto name_error; 2406e6309e75SThomas Gleixner } 24071da177e4SLinus Torvalds 24081e0b2cf9SKay Sievers pr_debug("device: '%s': %s\n", dev_name(dev), __func__); 2409c205ef48SGreg Kroah-Hartman 24101da177e4SLinus Torvalds parent = get_device(dev->parent); 2411ca22e56dSKay Sievers kobj = get_device_parent(dev, parent); 241284d0c27dSTetsuo Handa if (IS_ERR(kobj)) { 241384d0c27dSTetsuo Handa error = PTR_ERR(kobj); 241484d0c27dSTetsuo Handa goto parent_error; 241584d0c27dSTetsuo Handa } 2416ca22e56dSKay Sievers if (kobj) 2417ca22e56dSKay Sievers dev->kobj.parent = kobj; 24181da177e4SLinus Torvalds 24190d358f22SYinghai Lu /* use parent numa_node */ 242056f2de81SZhen Lei if (parent && (dev_to_node(dev) == NUMA_NO_NODE)) 24210d358f22SYinghai Lu set_dev_node(dev, dev_to_node(parent)); 24220d358f22SYinghai Lu 24231da177e4SLinus Torvalds /* first, register with generic layer. */ 24248a577ffcSKay Sievers /* we require the name to be set before, and pass NULL */ 24258a577ffcSKay Sievers error = kobject_add(&dev->kobj, dev->kobj.parent, NULL); 2426cebf8fd1SMing Lei if (error) { 2427cebf8fd1SMing Lei glue_dir = get_glue_dir(dev); 24281da177e4SLinus Torvalds goto Error; 2429cebf8fd1SMing Lei } 2430a7fd6706SKay Sievers 243137022644SBrian Walsh /* notify platform of device entry */ 243207de0e86SHeikki Krogerus error = device_platform_notify(dev, KOBJ_ADD); 243307de0e86SHeikki Krogerus if (error) 243407de0e86SHeikki Krogerus goto platform_error; 243537022644SBrian Walsh 2436c5e064a6SGreg Kroah-Hartman error = device_create_file(dev, &dev_attr_uevent); 2437a306eea4SCornelia Huck if (error) 2438a306eea4SCornelia Huck goto attrError; 2439a7fd6706SKay Sievers 24402ee97cafSCornelia Huck error = device_add_class_symlinks(dev); 24412ee97cafSCornelia Huck if (error) 24422ee97cafSCornelia Huck goto SymlinkError; 2443dc0afa83SCornelia Huck error = device_add_attrs(dev); 2444dc0afa83SCornelia Huck if (error) 24452620efefSGreg Kroah-Hartman goto AttrsError; 2446dc0afa83SCornelia Huck error = bus_add_device(dev); 2447dc0afa83SCornelia Huck if (error) 24481da177e4SLinus Torvalds goto BusError; 24493b98aeafSAlan Stern error = dpm_sysfs_add(dev); 245057eee3d2SRafael J. Wysocki if (error) 24513b98aeafSAlan Stern goto DPMError; 24523b98aeafSAlan Stern device_pm_add(dev); 2453ec0676eeSAlan Stern 24540cd75047SSergey Klyaus if (MAJOR(dev->devt)) { 24550cd75047SSergey Klyaus error = device_create_file(dev, &dev_attr_dev); 24560cd75047SSergey Klyaus if (error) 24570cd75047SSergey Klyaus goto DevAttrError; 24580cd75047SSergey Klyaus 24590cd75047SSergey Klyaus error = device_create_sys_dev_entry(dev); 24600cd75047SSergey Klyaus if (error) 24610cd75047SSergey Klyaus goto SysEntryError; 24620cd75047SSergey Klyaus 24630cd75047SSergey Klyaus devtmpfs_create_node(dev); 24640cd75047SSergey Klyaus } 24650cd75047SSergey Klyaus 2466ec0676eeSAlan Stern /* Notify clients of device addition. This call must come 2467268863f4Smajianpeng * after dpm_sysfs_add() and before kobject_uevent(). 2468ec0676eeSAlan Stern */ 2469ec0676eeSAlan Stern if (dev->bus) 2470ec0676eeSAlan Stern blocking_notifier_call_chain(&dev->bus->p->bus_notifier, 2471ec0676eeSAlan Stern BUS_NOTIFY_ADD_DEVICE, dev); 2472ec0676eeSAlan Stern 247353877d06SKay Sievers kobject_uevent(&dev->kobj, KOBJ_ADD); 2474372a67c0SSaravana Kannan 2475372a67c0SSaravana Kannan if (dev->fwnode && !dev->fwnode->dev) 2476372a67c0SSaravana Kannan dev->fwnode->dev = dev; 2477372a67c0SSaravana Kannan 2478e2ae9bccSSaravana Kannan /* 2479e2ae9bccSSaravana Kannan * Check if any of the other devices (consumers) have been waiting for 2480e2ae9bccSSaravana Kannan * this device (supplier) to be added so that they can create a device 2481e2ae9bccSSaravana Kannan * link to it. 2482e2ae9bccSSaravana Kannan * 2483e2ae9bccSSaravana Kannan * This needs to happen after device_pm_add() because device_link_add() 2484e2ae9bccSSaravana Kannan * requires the supplier be registered before it's called. 2485e2ae9bccSSaravana Kannan * 2486e2ae9bccSSaravana Kannan * But this also needs to happe before bus_probe_device() to make sure 2487e2ae9bccSSaravana Kannan * waiting consumers can link to it before the driver is bound to the 2488e2ae9bccSSaravana Kannan * device and the driver sync_state callback is called for this device. 2489e2ae9bccSSaravana Kannan */ 2490e2ae9bccSSaravana Kannan device_link_add_missing_supplier_links(); 2491e2ae9bccSSaravana Kannan 249203324507SSaravana Kannan if (fwnode_has_op(dev->fwnode, add_links)) { 249303324507SSaravana Kannan fw_ret = fwnode_call_int_op(dev->fwnode, add_links, dev); 249403324507SSaravana Kannan if (fw_ret == -ENODEV) 249503324507SSaravana Kannan device_link_wait_for_mandatory_supplier(dev); 249603324507SSaravana Kannan else if (fw_ret) 249703324507SSaravana Kannan device_link_wait_for_optional_supplier(dev); 249803324507SSaravana Kannan } 2499e2ae9bccSSaravana Kannan 25002023c610SAlan Stern bus_probe_device(dev); 25011da177e4SLinus Torvalds if (parent) 2502f791b8c8SGreg Kroah-Hartman klist_add_tail(&dev->p->knode_parent, 2503f791b8c8SGreg Kroah-Hartman &parent->p->klist_children); 25041da177e4SLinus Torvalds 25055d9fd169SGreg Kroah-Hartman if (dev->class) { 2506ca22e56dSKay Sievers mutex_lock(&dev->class->p->mutex); 2507c47ed219SGreg Kroah-Hartman /* tie the class to the device */ 2508570d0200SWei Yang klist_add_tail(&dev->p->knode_class, 25096b6e39a6SKay Sievers &dev->class->p->klist_devices); 2510c47ed219SGreg Kroah-Hartman 2511c47ed219SGreg Kroah-Hartman /* notify any interfaces that the device is here */ 2512184f1f77SGreg Kroah-Hartman list_for_each_entry(class_intf, 2513ca22e56dSKay Sievers &dev->class->p->interfaces, node) 2514c47ed219SGreg Kroah-Hartman if (class_intf->add_dev) 2515c47ed219SGreg Kroah-Hartman class_intf->add_dev(dev, class_intf); 2516ca22e56dSKay Sievers mutex_unlock(&dev->class->p->mutex); 25175d9fd169SGreg Kroah-Hartman } 2518c906a48aSGreg Kroah-Hartman done: 25191da177e4SLinus Torvalds put_device(dev); 25201da177e4SLinus Torvalds return error; 25210cd75047SSergey Klyaus SysEntryError: 25220cd75047SSergey Klyaus if (MAJOR(dev->devt)) 25230cd75047SSergey Klyaus device_remove_file(dev, &dev_attr_dev); 25240cd75047SSergey Klyaus DevAttrError: 25250cd75047SSergey Klyaus device_pm_remove(dev); 25260cd75047SSergey Klyaus dpm_sysfs_remove(dev); 25273b98aeafSAlan Stern DPMError: 252857eee3d2SRafael J. Wysocki bus_remove_device(dev); 252957eee3d2SRafael J. Wysocki BusError: 25302620efefSGreg Kroah-Hartman device_remove_attrs(dev); 25312620efefSGreg Kroah-Hartman AttrsError: 25322ee97cafSCornelia Huck device_remove_class_symlinks(dev); 25332ee97cafSCornelia Huck SymlinkError: 2534c5e064a6SGreg Kroah-Hartman device_remove_file(dev, &dev_attr_uevent); 253523681e47SGreg Kroah-Hartman attrError: 253607de0e86SHeikki Krogerus device_platform_notify(dev, KOBJ_REMOVE); 253707de0e86SHeikki Krogerus platform_error: 2538312c004dSKay Sievers kobject_uevent(&dev->kobj, KOBJ_REMOVE); 2539cebf8fd1SMing Lei glue_dir = get_glue_dir(dev); 25401da177e4SLinus Torvalds kobject_del(&dev->kobj); 25411da177e4SLinus Torvalds Error: 2542cebf8fd1SMing Lei cleanup_glue_dir(dev, glue_dir); 254384d0c27dSTetsuo Handa parent_error: 25441da177e4SLinus Torvalds put_device(parent); 25455c8563d7SKay Sievers name_error: 25465c8563d7SKay Sievers kfree(dev->p); 25475c8563d7SKay Sievers dev->p = NULL; 2548c906a48aSGreg Kroah-Hartman goto done; 25491da177e4SLinus Torvalds } 255086df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_add); 25511da177e4SLinus Torvalds 25521da177e4SLinus Torvalds /** 25531da177e4SLinus Torvalds * device_register - register a device with the system. 25541da177e4SLinus Torvalds * @dev: pointer to the device structure 25551da177e4SLinus Torvalds * 25561da177e4SLinus Torvalds * This happens in two clean steps - initialize the device 25571da177e4SLinus Torvalds * and add it to the system. The two steps can be called 25581da177e4SLinus Torvalds * separately, but this is the easiest and most common. 25591da177e4SLinus Torvalds * I.e. you should only call the two helpers separately if 25601da177e4SLinus Torvalds * have a clearly defined need to use and refcount the device 25611da177e4SLinus Torvalds * before it is added to the hierarchy. 25625739411aSCornelia Huck * 2563b10d5efdSAlan Stern * For more information, see the kerneldoc for device_initialize() 2564b10d5efdSAlan Stern * and device_add(). 2565b10d5efdSAlan Stern * 25665739411aSCornelia Huck * NOTE: _Never_ directly free @dev after calling this function, even 25675739411aSCornelia Huck * if it returned an error! Always use put_device() to give up the 25685739411aSCornelia Huck * reference initialized in this function instead. 25691da177e4SLinus Torvalds */ 25701da177e4SLinus Torvalds int device_register(struct device *dev) 25711da177e4SLinus Torvalds { 25721da177e4SLinus Torvalds device_initialize(dev); 25731da177e4SLinus Torvalds return device_add(dev); 25741da177e4SLinus Torvalds } 257586df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_register); 25761da177e4SLinus Torvalds 25771da177e4SLinus Torvalds /** 25781da177e4SLinus Torvalds * get_device - increment reference count for device. 25791da177e4SLinus Torvalds * @dev: device. 25801da177e4SLinus Torvalds * 25811da177e4SLinus Torvalds * This simply forwards the call to kobject_get(), though 25821da177e4SLinus Torvalds * we do take care to provide for the case that we get a NULL 25831da177e4SLinus Torvalds * pointer passed in. 25841da177e4SLinus Torvalds */ 25851da177e4SLinus Torvalds struct device *get_device(struct device *dev) 25861da177e4SLinus Torvalds { 2587b0d1f807SLars-Peter Clausen return dev ? kobj_to_dev(kobject_get(&dev->kobj)) : NULL; 25881da177e4SLinus Torvalds } 258986df2687SDavid Graham White EXPORT_SYMBOL_GPL(get_device); 25901da177e4SLinus Torvalds 25911da177e4SLinus Torvalds /** 25921da177e4SLinus Torvalds * put_device - decrement reference count. 25931da177e4SLinus Torvalds * @dev: device in question. 25941da177e4SLinus Torvalds */ 25951da177e4SLinus Torvalds void put_device(struct device *dev) 25961da177e4SLinus Torvalds { 2597edfaa7c3SKay Sievers /* might_sleep(); */ 25981da177e4SLinus Torvalds if (dev) 25991da177e4SLinus Torvalds kobject_put(&dev->kobj); 26001da177e4SLinus Torvalds } 260186df2687SDavid Graham White EXPORT_SYMBOL_GPL(put_device); 26021da177e4SLinus Torvalds 260300289cd8SDan Williams bool kill_device(struct device *dev) 260400289cd8SDan Williams { 260500289cd8SDan Williams /* 260600289cd8SDan Williams * Require the device lock and set the "dead" flag to guarantee that 260700289cd8SDan Williams * the update behavior is consistent with the other bitfields near 260800289cd8SDan Williams * it and that we cannot have an asynchronous probe routine trying 260900289cd8SDan Williams * to run while we are tearing out the bus/class/sysfs from 261000289cd8SDan Williams * underneath the device. 261100289cd8SDan Williams */ 261200289cd8SDan Williams lockdep_assert_held(&dev->mutex); 261300289cd8SDan Williams 261400289cd8SDan Williams if (dev->p->dead) 261500289cd8SDan Williams return false; 261600289cd8SDan Williams dev->p->dead = true; 261700289cd8SDan Williams return true; 261800289cd8SDan Williams } 261900289cd8SDan Williams EXPORT_SYMBOL_GPL(kill_device); 262000289cd8SDan Williams 26211da177e4SLinus Torvalds /** 26221da177e4SLinus Torvalds * device_del - delete device from system. 26231da177e4SLinus Torvalds * @dev: device. 26241da177e4SLinus Torvalds * 26251da177e4SLinus Torvalds * This is the first part of the device unregistration 26261da177e4SLinus Torvalds * sequence. This removes the device from the lists we control 26271da177e4SLinus Torvalds * from here, has it removed from the other driver model 26281da177e4SLinus Torvalds * subsystems it was added to in device_add(), and removes it 26291da177e4SLinus Torvalds * from the kobject hierarchy. 26301da177e4SLinus Torvalds * 26311da177e4SLinus Torvalds * NOTE: this should be called manually _iff_ device_add() was 26321da177e4SLinus Torvalds * also called manually. 26331da177e4SLinus Torvalds */ 26341da177e4SLinus Torvalds void device_del(struct device *dev) 26351da177e4SLinus Torvalds { 26361da177e4SLinus Torvalds struct device *parent = dev->parent; 2637cebf8fd1SMing Lei struct kobject *glue_dir = NULL; 2638c47ed219SGreg Kroah-Hartman struct class_interface *class_intf; 26391da177e4SLinus Torvalds 26403451a495SAlexander Duyck device_lock(dev); 264100289cd8SDan Williams kill_device(dev); 26423451a495SAlexander Duyck device_unlock(dev); 26433451a495SAlexander Duyck 2644372a67c0SSaravana Kannan if (dev->fwnode && dev->fwnode->dev == dev) 2645372a67c0SSaravana Kannan dev->fwnode->dev = NULL; 2646372a67c0SSaravana Kannan 2647ec0676eeSAlan Stern /* Notify clients of device removal. This call must come 2648ec0676eeSAlan Stern * before dpm_sysfs_remove(). 2649ec0676eeSAlan Stern */ 2650ec0676eeSAlan Stern if (dev->bus) 2651ec0676eeSAlan Stern blocking_notifier_call_chain(&dev->bus->p->bus_notifier, 2652ec0676eeSAlan Stern BUS_NOTIFY_DEL_DEVICE, dev); 26539ed98953SRafael J. Wysocki 26543b98aeafSAlan Stern dpm_sysfs_remove(dev); 26551da177e4SLinus Torvalds if (parent) 2656f791b8c8SGreg Kroah-Hartman klist_del(&dev->p->knode_parent); 2657e105b8bfSDan Williams if (MAJOR(dev->devt)) { 26582b2af54aSKay Sievers devtmpfs_delete_node(dev); 2659e105b8bfSDan Williams device_remove_sys_dev_entry(dev); 2660c5e064a6SGreg Kroah-Hartman device_remove_file(dev, &dev_attr_dev); 2661e105b8bfSDan Williams } 2662b9d9c82bSKay Sievers if (dev->class) { 2663da231fd5SKay Sievers device_remove_class_symlinks(dev); 266499ef3ef8SKay Sievers 2665ca22e56dSKay Sievers mutex_lock(&dev->class->p->mutex); 2666c47ed219SGreg Kroah-Hartman /* notify any interfaces that the device is now gone */ 2667184f1f77SGreg Kroah-Hartman list_for_each_entry(class_intf, 2668ca22e56dSKay Sievers &dev->class->p->interfaces, node) 2669c47ed219SGreg Kroah-Hartman if (class_intf->remove_dev) 2670c47ed219SGreg Kroah-Hartman class_intf->remove_dev(dev, class_intf); 2671c47ed219SGreg Kroah-Hartman /* remove the device from the class list */ 2672570d0200SWei Yang klist_del(&dev->p->knode_class); 2673ca22e56dSKay Sievers mutex_unlock(&dev->class->p->mutex); 2674b9d9c82bSKay Sievers } 2675c5e064a6SGreg Kroah-Hartman device_remove_file(dev, &dev_attr_uevent); 26762620efefSGreg Kroah-Hartman device_remove_attrs(dev); 267728953533SBenjamin Herrenschmidt bus_remove_device(dev); 26784b6d1f12SLongX Zhang device_pm_remove(dev); 2679d1c3414cSGrant Likely driver_deferred_probe_del(dev); 268007de0e86SHeikki Krogerus device_platform_notify(dev, KOBJ_REMOVE); 2681478573c9SLukas Wunner device_remove_properties(dev); 26822ec16150SJeffy Chen device_links_purge(dev); 26831da177e4SLinus Torvalds 2684599bad38SJoerg Roedel if (dev->bus) 2685599bad38SJoerg Roedel blocking_notifier_call_chain(&dev->bus->p->bus_notifier, 2686599bad38SJoerg Roedel BUS_NOTIFY_REMOVED_DEVICE, dev); 2687312c004dSKay Sievers kobject_uevent(&dev->kobj, KOBJ_REMOVE); 2688cebf8fd1SMing Lei glue_dir = get_glue_dir(dev); 26891da177e4SLinus Torvalds kobject_del(&dev->kobj); 2690cebf8fd1SMing Lei cleanup_glue_dir(dev, glue_dir); 26911da177e4SLinus Torvalds put_device(parent); 26921da177e4SLinus Torvalds } 269386df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_del); 26941da177e4SLinus Torvalds 26951da177e4SLinus Torvalds /** 26961da177e4SLinus Torvalds * device_unregister - unregister device from system. 26971da177e4SLinus Torvalds * @dev: device going away. 26981da177e4SLinus Torvalds * 26991da177e4SLinus Torvalds * We do this in two parts, like we do device_register(). First, 27001da177e4SLinus Torvalds * we remove it from all the subsystems with device_del(), then 27011da177e4SLinus Torvalds * we decrement the reference count via put_device(). If that 27021da177e4SLinus Torvalds * is the final reference count, the device will be cleaned up 27031da177e4SLinus Torvalds * via device_release() above. Otherwise, the structure will 27041da177e4SLinus Torvalds * stick around until the final reference to the device is dropped. 27051da177e4SLinus Torvalds */ 27061da177e4SLinus Torvalds void device_unregister(struct device *dev) 27071da177e4SLinus Torvalds { 27081e0b2cf9SKay Sievers pr_debug("device: '%s': %s\n", dev_name(dev), __func__); 27091da177e4SLinus Torvalds device_del(dev); 27101da177e4SLinus Torvalds put_device(dev); 27111da177e4SLinus Torvalds } 271286df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_unregister); 27131da177e4SLinus Torvalds 27143d060aebSAndy Shevchenko static struct device *prev_device(struct klist_iter *i) 27153d060aebSAndy Shevchenko { 27163d060aebSAndy Shevchenko struct klist_node *n = klist_prev(i); 27173d060aebSAndy Shevchenko struct device *dev = NULL; 27183d060aebSAndy Shevchenko struct device_private *p; 27193d060aebSAndy Shevchenko 27203d060aebSAndy Shevchenko if (n) { 27213d060aebSAndy Shevchenko p = to_device_private_parent(n); 27223d060aebSAndy Shevchenko dev = p->device; 27233d060aebSAndy Shevchenko } 27243d060aebSAndy Shevchenko return dev; 27253d060aebSAndy Shevchenko } 27263d060aebSAndy Shevchenko 272736239577Smochel@digitalimplant.org static struct device *next_device(struct klist_iter *i) 272836239577Smochel@digitalimplant.org { 272936239577Smochel@digitalimplant.org struct klist_node *n = klist_next(i); 2730f791b8c8SGreg Kroah-Hartman struct device *dev = NULL; 2731f791b8c8SGreg Kroah-Hartman struct device_private *p; 2732f791b8c8SGreg Kroah-Hartman 2733f791b8c8SGreg Kroah-Hartman if (n) { 2734f791b8c8SGreg Kroah-Hartman p = to_device_private_parent(n); 2735f791b8c8SGreg Kroah-Hartman dev = p->device; 2736f791b8c8SGreg Kroah-Hartman } 2737f791b8c8SGreg Kroah-Hartman return dev; 273836239577Smochel@digitalimplant.org } 273936239577Smochel@digitalimplant.org 27401da177e4SLinus Torvalds /** 2741e454cea2SKay Sievers * device_get_devnode - path of device node file 27426fcf53acSKay Sievers * @dev: device 2743e454cea2SKay Sievers * @mode: returned file access mode 27443c2670e6SKay Sievers * @uid: returned file owner 27453c2670e6SKay Sievers * @gid: returned file group 27466fcf53acSKay Sievers * @tmp: possibly allocated string 27476fcf53acSKay Sievers * 27486fcf53acSKay Sievers * Return the relative path of a possible device node. 27496fcf53acSKay Sievers * Non-default names may need to allocate a memory to compose 27506fcf53acSKay Sievers * a name. This memory is returned in tmp and needs to be 27516fcf53acSKay Sievers * freed by the caller. 27526fcf53acSKay Sievers */ 2753e454cea2SKay Sievers const char *device_get_devnode(struct device *dev, 27544e4098a3SGreg Kroah-Hartman umode_t *mode, kuid_t *uid, kgid_t *gid, 27553c2670e6SKay Sievers const char **tmp) 27566fcf53acSKay Sievers { 27576fcf53acSKay Sievers char *s; 27586fcf53acSKay Sievers 27596fcf53acSKay Sievers *tmp = NULL; 27606fcf53acSKay Sievers 27616fcf53acSKay Sievers /* the device type may provide a specific name */ 2762e454cea2SKay Sievers if (dev->type && dev->type->devnode) 27633c2670e6SKay Sievers *tmp = dev->type->devnode(dev, mode, uid, gid); 27646fcf53acSKay Sievers if (*tmp) 27656fcf53acSKay Sievers return *tmp; 27666fcf53acSKay Sievers 27676fcf53acSKay Sievers /* the class may provide a specific name */ 2768e454cea2SKay Sievers if (dev->class && dev->class->devnode) 2769e454cea2SKay Sievers *tmp = dev->class->devnode(dev, mode); 27706fcf53acSKay Sievers if (*tmp) 27716fcf53acSKay Sievers return *tmp; 27726fcf53acSKay Sievers 27736fcf53acSKay Sievers /* return name without allocation, tmp == NULL */ 27746fcf53acSKay Sievers if (strchr(dev_name(dev), '!') == NULL) 27756fcf53acSKay Sievers return dev_name(dev); 27766fcf53acSKay Sievers 27776fcf53acSKay Sievers /* replace '!' in the name with '/' */ 2778a29fd614SRasmus Villemoes s = kstrdup(dev_name(dev), GFP_KERNEL); 2779a29fd614SRasmus Villemoes if (!s) 27806fcf53acSKay Sievers return NULL; 2781a29fd614SRasmus Villemoes strreplace(s, '!', '/'); 2782a29fd614SRasmus Villemoes return *tmp = s; 27836fcf53acSKay Sievers } 27846fcf53acSKay Sievers 27856fcf53acSKay Sievers /** 27861da177e4SLinus Torvalds * device_for_each_child - device child iterator. 2787c41455fbSRandy Dunlap * @parent: parent struct device. 27881da177e4SLinus Torvalds * @fn: function to be called for each device. 2789f8878dcbSRobert P. J. Day * @data: data for the callback. 27901da177e4SLinus Torvalds * 2791c41455fbSRandy Dunlap * Iterate over @parent's child devices, and call @fn for each, 27921da177e4SLinus Torvalds * passing it @data. 27931da177e4SLinus Torvalds * 27941da177e4SLinus Torvalds * We check the return of @fn each time. If it returns anything 27951da177e4SLinus Torvalds * other than 0, we break out and return that value. 27961da177e4SLinus Torvalds */ 279736239577Smochel@digitalimplant.org int device_for_each_child(struct device *parent, void *data, 27984a3ad20cSGreg Kroah-Hartman int (*fn)(struct device *dev, void *data)) 27991da177e4SLinus Torvalds { 280036239577Smochel@digitalimplant.org struct klist_iter i; 28011da177e4SLinus Torvalds struct device *child; 28021da177e4SLinus Torvalds int error = 0; 28031da177e4SLinus Torvalds 2804014c90dbSGreg Kroah-Hartman if (!parent->p) 2805014c90dbSGreg Kroah-Hartman return 0; 2806014c90dbSGreg Kroah-Hartman 2807f791b8c8SGreg Kroah-Hartman klist_iter_init(&parent->p->klist_children, &i); 280893ead7c9SGimcuan Hui while (!error && (child = next_device(&i))) 280936239577Smochel@digitalimplant.org error = fn(child, data); 281036239577Smochel@digitalimplant.org klist_iter_exit(&i); 28111da177e4SLinus Torvalds return error; 28121da177e4SLinus Torvalds } 281386df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_for_each_child); 28141da177e4SLinus Torvalds 28155ab69981SCornelia Huck /** 28163d060aebSAndy Shevchenko * device_for_each_child_reverse - device child iterator in reversed order. 28173d060aebSAndy Shevchenko * @parent: parent struct device. 28183d060aebSAndy Shevchenko * @fn: function to be called for each device. 28193d060aebSAndy Shevchenko * @data: data for the callback. 28203d060aebSAndy Shevchenko * 28213d060aebSAndy Shevchenko * Iterate over @parent's child devices, and call @fn for each, 28223d060aebSAndy Shevchenko * passing it @data. 28233d060aebSAndy Shevchenko * 28243d060aebSAndy Shevchenko * We check the return of @fn each time. If it returns anything 28253d060aebSAndy Shevchenko * other than 0, we break out and return that value. 28263d060aebSAndy Shevchenko */ 28273d060aebSAndy Shevchenko int device_for_each_child_reverse(struct device *parent, void *data, 28283d060aebSAndy Shevchenko int (*fn)(struct device *dev, void *data)) 28293d060aebSAndy Shevchenko { 28303d060aebSAndy Shevchenko struct klist_iter i; 28313d060aebSAndy Shevchenko struct device *child; 28323d060aebSAndy Shevchenko int error = 0; 28333d060aebSAndy Shevchenko 28343d060aebSAndy Shevchenko if (!parent->p) 28353d060aebSAndy Shevchenko return 0; 28363d060aebSAndy Shevchenko 28373d060aebSAndy Shevchenko klist_iter_init(&parent->p->klist_children, &i); 28383d060aebSAndy Shevchenko while ((child = prev_device(&i)) && !error) 28393d060aebSAndy Shevchenko error = fn(child, data); 28403d060aebSAndy Shevchenko klist_iter_exit(&i); 28413d060aebSAndy Shevchenko return error; 28423d060aebSAndy Shevchenko } 28433d060aebSAndy Shevchenko EXPORT_SYMBOL_GPL(device_for_each_child_reverse); 28443d060aebSAndy Shevchenko 28453d060aebSAndy Shevchenko /** 28465ab69981SCornelia Huck * device_find_child - device iterator for locating a particular device. 28475ab69981SCornelia Huck * @parent: parent struct device 28485ab69981SCornelia Huck * @match: Callback function to check device 2849f8878dcbSRobert P. J. Day * @data: Data to pass to match function 28505ab69981SCornelia Huck * 28515ab69981SCornelia Huck * This is similar to the device_for_each_child() function above, but it 28525ab69981SCornelia Huck * returns a reference to a device that is 'found' for later use, as 28535ab69981SCornelia Huck * determined by the @match callback. 28545ab69981SCornelia Huck * 28555ab69981SCornelia Huck * The callback should return 0 if the device doesn't match and non-zero 28565ab69981SCornelia Huck * if it does. If the callback returns non-zero and a reference to the 28575ab69981SCornelia Huck * current device can be obtained, this function will return to the caller 28585ab69981SCornelia Huck * and not iterate over any more devices. 2859a4e2400aSFederico Vaga * 2860a4e2400aSFederico Vaga * NOTE: you will need to drop the reference with put_device() after use. 28615ab69981SCornelia Huck */ 28625ab69981SCornelia Huck struct device *device_find_child(struct device *parent, void *data, 28634a3ad20cSGreg Kroah-Hartman int (*match)(struct device *dev, void *data)) 28645ab69981SCornelia Huck { 28655ab69981SCornelia Huck struct klist_iter i; 28665ab69981SCornelia Huck struct device *child; 28675ab69981SCornelia Huck 28685ab69981SCornelia Huck if (!parent) 28695ab69981SCornelia Huck return NULL; 28705ab69981SCornelia Huck 2871f791b8c8SGreg Kroah-Hartman klist_iter_init(&parent->p->klist_children, &i); 28725ab69981SCornelia Huck while ((child = next_device(&i))) 28735ab69981SCornelia Huck if (match(child, data) && get_device(child)) 28745ab69981SCornelia Huck break; 28755ab69981SCornelia Huck klist_iter_exit(&i); 28765ab69981SCornelia Huck return child; 28775ab69981SCornelia Huck } 287886df2687SDavid Graham White EXPORT_SYMBOL_GPL(device_find_child); 28795ab69981SCornelia Huck 2880dad9bb01SHeikki Krogerus /** 2881dad9bb01SHeikki Krogerus * device_find_child_by_name - device iterator for locating a child device. 2882dad9bb01SHeikki Krogerus * @parent: parent struct device 2883dad9bb01SHeikki Krogerus * @name: name of the child device 2884dad9bb01SHeikki Krogerus * 2885dad9bb01SHeikki Krogerus * This is similar to the device_find_child() function above, but it 2886dad9bb01SHeikki Krogerus * returns a reference to a device that has the name @name. 2887dad9bb01SHeikki Krogerus * 2888dad9bb01SHeikki Krogerus * NOTE: you will need to drop the reference with put_device() after use. 2889dad9bb01SHeikki Krogerus */ 2890dad9bb01SHeikki Krogerus struct device *device_find_child_by_name(struct device *parent, 2891dad9bb01SHeikki Krogerus const char *name) 2892dad9bb01SHeikki Krogerus { 2893dad9bb01SHeikki Krogerus struct klist_iter i; 2894dad9bb01SHeikki Krogerus struct device *child; 2895dad9bb01SHeikki Krogerus 2896dad9bb01SHeikki Krogerus if (!parent) 2897dad9bb01SHeikki Krogerus return NULL; 2898dad9bb01SHeikki Krogerus 2899dad9bb01SHeikki Krogerus klist_iter_init(&parent->p->klist_children, &i); 2900dad9bb01SHeikki Krogerus while ((child = next_device(&i))) 2901dad9bb01SHeikki Krogerus if (!strcmp(dev_name(child), name) && get_device(child)) 2902dad9bb01SHeikki Krogerus break; 2903dad9bb01SHeikki Krogerus klist_iter_exit(&i); 2904dad9bb01SHeikki Krogerus return child; 2905dad9bb01SHeikki Krogerus } 2906dad9bb01SHeikki Krogerus EXPORT_SYMBOL_GPL(device_find_child_by_name); 2907dad9bb01SHeikki Krogerus 29081da177e4SLinus Torvalds int __init devices_init(void) 29091da177e4SLinus Torvalds { 2910881c6cfdSGreg Kroah-Hartman devices_kset = kset_create_and_add("devices", &device_uevent_ops, NULL); 2911881c6cfdSGreg Kroah-Hartman if (!devices_kset) 2912881c6cfdSGreg Kroah-Hartman return -ENOMEM; 2913e105b8bfSDan Williams dev_kobj = kobject_create_and_add("dev", NULL); 2914e105b8bfSDan Williams if (!dev_kobj) 2915e105b8bfSDan Williams goto dev_kobj_err; 2916e105b8bfSDan Williams sysfs_dev_block_kobj = kobject_create_and_add("block", dev_kobj); 2917e105b8bfSDan Williams if (!sysfs_dev_block_kobj) 2918e105b8bfSDan Williams goto block_kobj_err; 2919e105b8bfSDan Williams sysfs_dev_char_kobj = kobject_create_and_add("char", dev_kobj); 2920e105b8bfSDan Williams if (!sysfs_dev_char_kobj) 2921e105b8bfSDan Williams goto char_kobj_err; 2922e105b8bfSDan Williams 2923881c6cfdSGreg Kroah-Hartman return 0; 2924e105b8bfSDan Williams 2925e105b8bfSDan Williams char_kobj_err: 2926e105b8bfSDan Williams kobject_put(sysfs_dev_block_kobj); 2927e105b8bfSDan Williams block_kobj_err: 2928e105b8bfSDan Williams kobject_put(dev_kobj); 2929e105b8bfSDan Williams dev_kobj_err: 2930e105b8bfSDan Williams kset_unregister(devices_kset); 2931e105b8bfSDan Williams return -ENOMEM; 29321da177e4SLinus Torvalds } 29331da177e4SLinus Torvalds 29344f3549d7SRafael J. Wysocki static int device_check_offline(struct device *dev, void *not_used) 29354f3549d7SRafael J. Wysocki { 29364f3549d7SRafael J. Wysocki int ret; 29374f3549d7SRafael J. Wysocki 29384f3549d7SRafael J. Wysocki ret = device_for_each_child(dev, NULL, device_check_offline); 29394f3549d7SRafael J. Wysocki if (ret) 29404f3549d7SRafael J. Wysocki return ret; 29414f3549d7SRafael J. Wysocki 29424f3549d7SRafael J. Wysocki return device_supports_offline(dev) && !dev->offline ? -EBUSY : 0; 29434f3549d7SRafael J. Wysocki } 29444f3549d7SRafael J. Wysocki 29454f3549d7SRafael J. Wysocki /** 29464f3549d7SRafael J. Wysocki * device_offline - Prepare the device for hot-removal. 29474f3549d7SRafael J. Wysocki * @dev: Device to be put offline. 29484f3549d7SRafael J. Wysocki * 29494f3549d7SRafael J. Wysocki * Execute the device bus type's .offline() callback, if present, to prepare 29504f3549d7SRafael J. Wysocki * the device for a subsequent hot-removal. If that succeeds, the device must 29514f3549d7SRafael J. Wysocki * not be used until either it is removed or its bus type's .online() callback 29524f3549d7SRafael J. Wysocki * is executed. 29534f3549d7SRafael J. Wysocki * 29544f3549d7SRafael J. Wysocki * Call under device_hotplug_lock. 29554f3549d7SRafael J. Wysocki */ 29564f3549d7SRafael J. Wysocki int device_offline(struct device *dev) 29574f3549d7SRafael J. Wysocki { 29584f3549d7SRafael J. Wysocki int ret; 29594f3549d7SRafael J. Wysocki 29604f3549d7SRafael J. Wysocki if (dev->offline_disabled) 29614f3549d7SRafael J. Wysocki return -EPERM; 29624f3549d7SRafael J. Wysocki 29634f3549d7SRafael J. Wysocki ret = device_for_each_child(dev, NULL, device_check_offline); 29644f3549d7SRafael J. Wysocki if (ret) 29654f3549d7SRafael J. Wysocki return ret; 29664f3549d7SRafael J. Wysocki 29674f3549d7SRafael J. Wysocki device_lock(dev); 29684f3549d7SRafael J. Wysocki if (device_supports_offline(dev)) { 29694f3549d7SRafael J. Wysocki if (dev->offline) { 29704f3549d7SRafael J. Wysocki ret = 1; 29714f3549d7SRafael J. Wysocki } else { 29724f3549d7SRafael J. Wysocki ret = dev->bus->offline(dev); 29734f3549d7SRafael J. Wysocki if (!ret) { 29744f3549d7SRafael J. Wysocki kobject_uevent(&dev->kobj, KOBJ_OFFLINE); 29754f3549d7SRafael J. Wysocki dev->offline = true; 29764f3549d7SRafael J. Wysocki } 29774f3549d7SRafael J. Wysocki } 29784f3549d7SRafael J. Wysocki } 29794f3549d7SRafael J. Wysocki device_unlock(dev); 29804f3549d7SRafael J. Wysocki 29814f3549d7SRafael J. Wysocki return ret; 29824f3549d7SRafael J. Wysocki } 29834f3549d7SRafael J. Wysocki 29844f3549d7SRafael J. Wysocki /** 29854f3549d7SRafael J. Wysocki * device_online - Put the device back online after successful device_offline(). 29864f3549d7SRafael J. Wysocki * @dev: Device to be put back online. 29874f3549d7SRafael J. Wysocki * 29884f3549d7SRafael J. Wysocki * If device_offline() has been successfully executed for @dev, but the device 29894f3549d7SRafael J. Wysocki * has not been removed subsequently, execute its bus type's .online() callback 29904f3549d7SRafael J. Wysocki * to indicate that the device can be used again. 29914f3549d7SRafael J. Wysocki * 29924f3549d7SRafael J. Wysocki * Call under device_hotplug_lock. 29934f3549d7SRafael J. Wysocki */ 29944f3549d7SRafael J. Wysocki int device_online(struct device *dev) 29954f3549d7SRafael J. Wysocki { 29964f3549d7SRafael J. Wysocki int ret = 0; 29974f3549d7SRafael J. Wysocki 29984f3549d7SRafael J. Wysocki device_lock(dev); 29994f3549d7SRafael J. Wysocki if (device_supports_offline(dev)) { 30004f3549d7SRafael J. Wysocki if (dev->offline) { 30014f3549d7SRafael J. Wysocki ret = dev->bus->online(dev); 30024f3549d7SRafael J. Wysocki if (!ret) { 30034f3549d7SRafael J. Wysocki kobject_uevent(&dev->kobj, KOBJ_ONLINE); 30044f3549d7SRafael J. Wysocki dev->offline = false; 30054f3549d7SRafael J. Wysocki } 30064f3549d7SRafael J. Wysocki } else { 30074f3549d7SRafael J. Wysocki ret = 1; 30084f3549d7SRafael J. Wysocki } 30094f3549d7SRafael J. Wysocki } 30104f3549d7SRafael J. Wysocki device_unlock(dev); 30114f3549d7SRafael J. Wysocki 30124f3549d7SRafael J. Wysocki return ret; 30134f3549d7SRafael J. Wysocki } 30144f3549d7SRafael J. Wysocki 30157f100d15SKarthigan Srinivasan struct root_device { 30160aa0dc41SMark McLoughlin struct device dev; 30170aa0dc41SMark McLoughlin struct module *owner; 30180aa0dc41SMark McLoughlin }; 30190aa0dc41SMark McLoughlin 302093058424SJosh Triplett static inline struct root_device *to_root_device(struct device *d) 3021481e2079SFerenc Wagner { 3022481e2079SFerenc Wagner return container_of(d, struct root_device, dev); 3023481e2079SFerenc Wagner } 30240aa0dc41SMark McLoughlin 30250aa0dc41SMark McLoughlin static void root_device_release(struct device *dev) 30260aa0dc41SMark McLoughlin { 30270aa0dc41SMark McLoughlin kfree(to_root_device(dev)); 30280aa0dc41SMark McLoughlin } 30290aa0dc41SMark McLoughlin 30300aa0dc41SMark McLoughlin /** 30310aa0dc41SMark McLoughlin * __root_device_register - allocate and register a root device 30320aa0dc41SMark McLoughlin * @name: root device name 30330aa0dc41SMark McLoughlin * @owner: owner module of the root device, usually THIS_MODULE 30340aa0dc41SMark McLoughlin * 30350aa0dc41SMark McLoughlin * This function allocates a root device and registers it 30360aa0dc41SMark McLoughlin * using device_register(). In order to free the returned 30370aa0dc41SMark McLoughlin * device, use root_device_unregister(). 30380aa0dc41SMark McLoughlin * 30390aa0dc41SMark McLoughlin * Root devices are dummy devices which allow other devices 30400aa0dc41SMark McLoughlin * to be grouped under /sys/devices. Use this function to 30410aa0dc41SMark McLoughlin * allocate a root device and then use it as the parent of 30420aa0dc41SMark McLoughlin * any device which should appear under /sys/devices/{name} 30430aa0dc41SMark McLoughlin * 30440aa0dc41SMark McLoughlin * The /sys/devices/{name} directory will also contain a 30450aa0dc41SMark McLoughlin * 'module' symlink which points to the @owner directory 30460aa0dc41SMark McLoughlin * in sysfs. 30470aa0dc41SMark McLoughlin * 3048f0eae0edSJani Nikula * Returns &struct device pointer on success, or ERR_PTR() on error. 3049f0eae0edSJani Nikula * 30500aa0dc41SMark McLoughlin * Note: You probably want to use root_device_register(). 30510aa0dc41SMark McLoughlin */ 30520aa0dc41SMark McLoughlin struct device *__root_device_register(const char *name, struct module *owner) 30530aa0dc41SMark McLoughlin { 30540aa0dc41SMark McLoughlin struct root_device *root; 30550aa0dc41SMark McLoughlin int err = -ENOMEM; 30560aa0dc41SMark McLoughlin 30570aa0dc41SMark McLoughlin root = kzalloc(sizeof(struct root_device), GFP_KERNEL); 30580aa0dc41SMark McLoughlin if (!root) 30590aa0dc41SMark McLoughlin return ERR_PTR(err); 30600aa0dc41SMark McLoughlin 3061acc0e90fSGreg Kroah-Hartman err = dev_set_name(&root->dev, "%s", name); 30620aa0dc41SMark McLoughlin if (err) { 30630aa0dc41SMark McLoughlin kfree(root); 30640aa0dc41SMark McLoughlin return ERR_PTR(err); 30650aa0dc41SMark McLoughlin } 30660aa0dc41SMark McLoughlin 30670aa0dc41SMark McLoughlin root->dev.release = root_device_release; 30680aa0dc41SMark McLoughlin 30690aa0dc41SMark McLoughlin err = device_register(&root->dev); 30700aa0dc41SMark McLoughlin if (err) { 30710aa0dc41SMark McLoughlin put_device(&root->dev); 30720aa0dc41SMark McLoughlin return ERR_PTR(err); 30730aa0dc41SMark McLoughlin } 30740aa0dc41SMark McLoughlin 30751d9e882bSChristoph Egger #ifdef CONFIG_MODULES /* gotta find a "cleaner" way to do this */ 30760aa0dc41SMark McLoughlin if (owner) { 30770aa0dc41SMark McLoughlin struct module_kobject *mk = &owner->mkobj; 30780aa0dc41SMark McLoughlin 30790aa0dc41SMark McLoughlin err = sysfs_create_link(&root->dev.kobj, &mk->kobj, "module"); 30800aa0dc41SMark McLoughlin if (err) { 30810aa0dc41SMark McLoughlin device_unregister(&root->dev); 30820aa0dc41SMark McLoughlin return ERR_PTR(err); 30830aa0dc41SMark McLoughlin } 30840aa0dc41SMark McLoughlin root->owner = owner; 30850aa0dc41SMark McLoughlin } 30860aa0dc41SMark McLoughlin #endif 30870aa0dc41SMark McLoughlin 30880aa0dc41SMark McLoughlin return &root->dev; 30890aa0dc41SMark McLoughlin } 30900aa0dc41SMark McLoughlin EXPORT_SYMBOL_GPL(__root_device_register); 30910aa0dc41SMark McLoughlin 30920aa0dc41SMark McLoughlin /** 30930aa0dc41SMark McLoughlin * root_device_unregister - unregister and free a root device 30947cbcf225SRandy Dunlap * @dev: device going away 30950aa0dc41SMark McLoughlin * 30960aa0dc41SMark McLoughlin * This function unregisters and cleans up a device that was created by 30970aa0dc41SMark McLoughlin * root_device_register(). 30980aa0dc41SMark McLoughlin */ 30990aa0dc41SMark McLoughlin void root_device_unregister(struct device *dev) 31000aa0dc41SMark McLoughlin { 31010aa0dc41SMark McLoughlin struct root_device *root = to_root_device(dev); 31020aa0dc41SMark McLoughlin 31030aa0dc41SMark McLoughlin if (root->owner) 31040aa0dc41SMark McLoughlin sysfs_remove_link(&root->dev.kobj, "module"); 31050aa0dc41SMark McLoughlin 31060aa0dc41SMark McLoughlin device_unregister(dev); 31070aa0dc41SMark McLoughlin } 31080aa0dc41SMark McLoughlin EXPORT_SYMBOL_GPL(root_device_unregister); 31090aa0dc41SMark McLoughlin 311023681e47SGreg Kroah-Hartman 311123681e47SGreg Kroah-Hartman static void device_create_release(struct device *dev) 311223681e47SGreg Kroah-Hartman { 31131e0b2cf9SKay Sievers pr_debug("device: '%s': %s\n", dev_name(dev), __func__); 311423681e47SGreg Kroah-Hartman kfree(dev); 311523681e47SGreg Kroah-Hartman } 311623681e47SGreg Kroah-Hartman 31176a8b55d7SMathieu Malaterre static __printf(6, 0) struct device * 311839ef3112SGuenter Roeck device_create_groups_vargs(struct class *class, struct device *parent, 311939ef3112SGuenter Roeck dev_t devt, void *drvdata, 312039ef3112SGuenter Roeck const struct attribute_group **groups, 312139ef3112SGuenter Roeck const char *fmt, va_list args) 312239ef3112SGuenter Roeck { 312339ef3112SGuenter Roeck struct device *dev = NULL; 312439ef3112SGuenter Roeck int retval = -ENODEV; 312539ef3112SGuenter Roeck 312639ef3112SGuenter Roeck if (class == NULL || IS_ERR(class)) 312739ef3112SGuenter Roeck goto error; 312839ef3112SGuenter Roeck 312939ef3112SGuenter Roeck dev = kzalloc(sizeof(*dev), GFP_KERNEL); 313039ef3112SGuenter Roeck if (!dev) { 313139ef3112SGuenter Roeck retval = -ENOMEM; 313239ef3112SGuenter Roeck goto error; 313339ef3112SGuenter Roeck } 313439ef3112SGuenter Roeck 3135bbc780f8SDavid Herrmann device_initialize(dev); 313639ef3112SGuenter Roeck dev->devt = devt; 313739ef3112SGuenter Roeck dev->class = class; 313839ef3112SGuenter Roeck dev->parent = parent; 313939ef3112SGuenter Roeck dev->groups = groups; 314039ef3112SGuenter Roeck dev->release = device_create_release; 314139ef3112SGuenter Roeck dev_set_drvdata(dev, drvdata); 314239ef3112SGuenter Roeck 314339ef3112SGuenter Roeck retval = kobject_set_name_vargs(&dev->kobj, fmt, args); 314439ef3112SGuenter Roeck if (retval) 314539ef3112SGuenter Roeck goto error; 314639ef3112SGuenter Roeck 3147bbc780f8SDavid Herrmann retval = device_add(dev); 314839ef3112SGuenter Roeck if (retval) 314939ef3112SGuenter Roeck goto error; 315039ef3112SGuenter Roeck 315139ef3112SGuenter Roeck return dev; 315239ef3112SGuenter Roeck 315339ef3112SGuenter Roeck error: 315439ef3112SGuenter Roeck put_device(dev); 315539ef3112SGuenter Roeck return ERR_PTR(retval); 315639ef3112SGuenter Roeck } 315739ef3112SGuenter Roeck 315823681e47SGreg Kroah-Hartman /** 31598882b394SGreg Kroah-Hartman * device_create_vargs - creates a device and registers it with sysfs 31608882b394SGreg Kroah-Hartman * @class: pointer to the struct class that this device should be registered to 31618882b394SGreg Kroah-Hartman * @parent: pointer to the parent struct device of this new device, if any 31628882b394SGreg Kroah-Hartman * @devt: the dev_t for the char device to be added 31638882b394SGreg Kroah-Hartman * @drvdata: the data to be added to the device for callbacks 31648882b394SGreg Kroah-Hartman * @fmt: string for the device's name 31658882b394SGreg Kroah-Hartman * @args: va_list for the device's name 31668882b394SGreg Kroah-Hartman * 31678882b394SGreg Kroah-Hartman * This function can be used by char device classes. A struct device 31688882b394SGreg Kroah-Hartman * will be created in sysfs, registered to the specified class. 31698882b394SGreg Kroah-Hartman * 31708882b394SGreg Kroah-Hartman * A "dev" file will be created, showing the dev_t for the device, if 31718882b394SGreg Kroah-Hartman * the dev_t is not 0,0. 31728882b394SGreg Kroah-Hartman * If a pointer to a parent struct device is passed in, the newly created 31738882b394SGreg Kroah-Hartman * struct device will be a child of that device in sysfs. 31748882b394SGreg Kroah-Hartman * The pointer to the struct device will be returned from the call. 31758882b394SGreg Kroah-Hartman * Any further sysfs files that might be required can be created using this 31768882b394SGreg Kroah-Hartman * pointer. 31778882b394SGreg Kroah-Hartman * 3178f0eae0edSJani Nikula * Returns &struct device pointer on success, or ERR_PTR() on error. 3179f0eae0edSJani Nikula * 31808882b394SGreg Kroah-Hartman * Note: the struct class passed to this function must have previously 31818882b394SGreg Kroah-Hartman * been created with a call to class_create(). 31828882b394SGreg Kroah-Hartman */ 31838882b394SGreg Kroah-Hartman struct device *device_create_vargs(struct class *class, struct device *parent, 31848882b394SGreg Kroah-Hartman dev_t devt, void *drvdata, const char *fmt, 31858882b394SGreg Kroah-Hartman va_list args) 31868882b394SGreg Kroah-Hartman { 318739ef3112SGuenter Roeck return device_create_groups_vargs(class, parent, devt, drvdata, NULL, 318839ef3112SGuenter Roeck fmt, args); 31898882b394SGreg Kroah-Hartman } 31908882b394SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(device_create_vargs); 31918882b394SGreg Kroah-Hartman 31928882b394SGreg Kroah-Hartman /** 31934e106739SGreg Kroah-Hartman * device_create - creates a device and registers it with sysfs 31948882b394SGreg Kroah-Hartman * @class: pointer to the struct class that this device should be registered to 31958882b394SGreg Kroah-Hartman * @parent: pointer to the parent struct device of this new device, if any 31968882b394SGreg Kroah-Hartman * @devt: the dev_t for the char device to be added 31978882b394SGreg Kroah-Hartman * @drvdata: the data to be added to the device for callbacks 31988882b394SGreg Kroah-Hartman * @fmt: string for the device's name 31998882b394SGreg Kroah-Hartman * 32008882b394SGreg Kroah-Hartman * This function can be used by char device classes. A struct device 32018882b394SGreg Kroah-Hartman * will be created in sysfs, registered to the specified class. 32028882b394SGreg Kroah-Hartman * 32038882b394SGreg Kroah-Hartman * A "dev" file will be created, showing the dev_t for the device, if 32048882b394SGreg Kroah-Hartman * the dev_t is not 0,0. 32058882b394SGreg Kroah-Hartman * If a pointer to a parent struct device is passed in, the newly created 32068882b394SGreg Kroah-Hartman * struct device will be a child of that device in sysfs. 32078882b394SGreg Kroah-Hartman * The pointer to the struct device will be returned from the call. 32088882b394SGreg Kroah-Hartman * Any further sysfs files that might be required can be created using this 32098882b394SGreg Kroah-Hartman * pointer. 32108882b394SGreg Kroah-Hartman * 3211f0eae0edSJani Nikula * Returns &struct device pointer on success, or ERR_PTR() on error. 3212f0eae0edSJani Nikula * 32138882b394SGreg Kroah-Hartman * Note: the struct class passed to this function must have previously 32148882b394SGreg Kroah-Hartman * been created with a call to class_create(). 32158882b394SGreg Kroah-Hartman */ 32164e106739SGreg Kroah-Hartman struct device *device_create(struct class *class, struct device *parent, 32174e106739SGreg Kroah-Hartman dev_t devt, void *drvdata, const char *fmt, ...) 32188882b394SGreg Kroah-Hartman { 32198882b394SGreg Kroah-Hartman va_list vargs; 32208882b394SGreg Kroah-Hartman struct device *dev; 32218882b394SGreg Kroah-Hartman 32228882b394SGreg Kroah-Hartman va_start(vargs, fmt); 32238882b394SGreg Kroah-Hartman dev = device_create_vargs(class, parent, devt, drvdata, fmt, vargs); 32248882b394SGreg Kroah-Hartman va_end(vargs); 32258882b394SGreg Kroah-Hartman return dev; 32268882b394SGreg Kroah-Hartman } 32274e106739SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(device_create); 32288882b394SGreg Kroah-Hartman 322939ef3112SGuenter Roeck /** 323039ef3112SGuenter Roeck * device_create_with_groups - creates a device and registers it with sysfs 323139ef3112SGuenter Roeck * @class: pointer to the struct class that this device should be registered to 323239ef3112SGuenter Roeck * @parent: pointer to the parent struct device of this new device, if any 323339ef3112SGuenter Roeck * @devt: the dev_t for the char device to be added 323439ef3112SGuenter Roeck * @drvdata: the data to be added to the device for callbacks 323539ef3112SGuenter Roeck * @groups: NULL-terminated list of attribute groups to be created 323639ef3112SGuenter Roeck * @fmt: string for the device's name 323739ef3112SGuenter Roeck * 323839ef3112SGuenter Roeck * This function can be used by char device classes. A struct device 323939ef3112SGuenter Roeck * will be created in sysfs, registered to the specified class. 324039ef3112SGuenter Roeck * Additional attributes specified in the groups parameter will also 324139ef3112SGuenter Roeck * be created automatically. 324239ef3112SGuenter Roeck * 324339ef3112SGuenter Roeck * A "dev" file will be created, showing the dev_t for the device, if 324439ef3112SGuenter Roeck * the dev_t is not 0,0. 324539ef3112SGuenter Roeck * If a pointer to a parent struct device is passed in, the newly created 324639ef3112SGuenter Roeck * struct device will be a child of that device in sysfs. 324739ef3112SGuenter Roeck * The pointer to the struct device will be returned from the call. 324839ef3112SGuenter Roeck * Any further sysfs files that might be required can be created using this 324939ef3112SGuenter Roeck * pointer. 325039ef3112SGuenter Roeck * 325139ef3112SGuenter Roeck * Returns &struct device pointer on success, or ERR_PTR() on error. 325239ef3112SGuenter Roeck * 325339ef3112SGuenter Roeck * Note: the struct class passed to this function must have previously 325439ef3112SGuenter Roeck * been created with a call to class_create(). 325539ef3112SGuenter Roeck */ 325639ef3112SGuenter Roeck struct device *device_create_with_groups(struct class *class, 325739ef3112SGuenter Roeck struct device *parent, dev_t devt, 325839ef3112SGuenter Roeck void *drvdata, 325939ef3112SGuenter Roeck const struct attribute_group **groups, 326039ef3112SGuenter Roeck const char *fmt, ...) 326139ef3112SGuenter Roeck { 326239ef3112SGuenter Roeck va_list vargs; 326339ef3112SGuenter Roeck struct device *dev; 326439ef3112SGuenter Roeck 326539ef3112SGuenter Roeck va_start(vargs, fmt); 326639ef3112SGuenter Roeck dev = device_create_groups_vargs(class, parent, devt, drvdata, groups, 326739ef3112SGuenter Roeck fmt, vargs); 326839ef3112SGuenter Roeck va_end(vargs); 326939ef3112SGuenter Roeck return dev; 327039ef3112SGuenter Roeck } 327139ef3112SGuenter Roeck EXPORT_SYMBOL_GPL(device_create_with_groups); 327239ef3112SGuenter Roeck 3273775b64d2SRafael J. Wysocki /** 3274775b64d2SRafael J. Wysocki * device_destroy - removes a device that was created with device_create() 3275775b64d2SRafael J. Wysocki * @class: pointer to the struct class that this device was registered with 3276775b64d2SRafael J. Wysocki * @devt: the dev_t of the device that was previously registered 3277775b64d2SRafael J. Wysocki * 3278775b64d2SRafael J. Wysocki * This call unregisters and cleans up a device that was created with a 3279775b64d2SRafael J. Wysocki * call to device_create(). 3280775b64d2SRafael J. Wysocki */ 3281775b64d2SRafael J. Wysocki void device_destroy(struct class *class, dev_t devt) 3282775b64d2SRafael J. Wysocki { 3283775b64d2SRafael J. Wysocki struct device *dev; 3284775b64d2SRafael J. Wysocki 32854495dfddSSuzuki K Poulose dev = class_find_device_by_devt(class, devt); 3286cd35449bSDave Young if (dev) { 3287cd35449bSDave Young put_device(dev); 328823681e47SGreg Kroah-Hartman device_unregister(dev); 328923681e47SGreg Kroah-Hartman } 3290cd35449bSDave Young } 329123681e47SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(device_destroy); 3292a2de48caSGreg Kroah-Hartman 3293a2de48caSGreg Kroah-Hartman /** 3294a2de48caSGreg Kroah-Hartman * device_rename - renames a device 3295a2de48caSGreg Kroah-Hartman * @dev: the pointer to the struct device to be renamed 3296a2de48caSGreg Kroah-Hartman * @new_name: the new name of the device 3297030c1d2bSEric W. Biederman * 3298030c1d2bSEric W. Biederman * It is the responsibility of the caller to provide mutual 3299030c1d2bSEric W. Biederman * exclusion between two different calls of device_rename 3300030c1d2bSEric W. Biederman * on the same device to ensure that new_name is valid and 3301030c1d2bSEric W. Biederman * won't conflict with other devices. 3302c6c0ac66SMichael Ellerman * 3303a5462516STimur Tabi * Note: Don't call this function. Currently, the networking layer calls this 3304a5462516STimur Tabi * function, but that will change. The following text from Kay Sievers offers 3305a5462516STimur Tabi * some insight: 3306a5462516STimur Tabi * 3307a5462516STimur Tabi * Renaming devices is racy at many levels, symlinks and other stuff are not 3308a5462516STimur Tabi * replaced atomically, and you get a "move" uevent, but it's not easy to 3309a5462516STimur Tabi * connect the event to the old and new device. Device nodes are not renamed at 3310a5462516STimur Tabi * all, there isn't even support for that in the kernel now. 3311a5462516STimur Tabi * 3312a5462516STimur Tabi * In the meantime, during renaming, your target name might be taken by another 3313a5462516STimur Tabi * driver, creating conflicts. Or the old name is taken directly after you 3314a5462516STimur Tabi * renamed it -- then you get events for the same DEVPATH, before you even see 3315a5462516STimur Tabi * the "move" event. It's just a mess, and nothing new should ever rely on 3316a5462516STimur Tabi * kernel device renaming. Besides that, it's not even implemented now for 3317a5462516STimur Tabi * other things than (driver-core wise very simple) network devices. 3318a5462516STimur Tabi * 3319a5462516STimur Tabi * We are currently about to change network renaming in udev to completely 3320a5462516STimur Tabi * disallow renaming of devices in the same namespace as the kernel uses, 3321a5462516STimur Tabi * because we can't solve the problems properly, that arise with swapping names 3322a5462516STimur Tabi * of multiple interfaces without races. Means, renaming of eth[0-9]* will only 3323a5462516STimur Tabi * be allowed to some other name than eth[0-9]*, for the aforementioned 3324a5462516STimur Tabi * reasons. 3325a5462516STimur Tabi * 3326a5462516STimur Tabi * Make up a "real" name in the driver before you register anything, or add 3327a5462516STimur Tabi * some other attributes for userspace to find the device, or use udev to add 3328a5462516STimur Tabi * symlinks -- but never rename kernel devices later, it's a complete mess. We 3329a5462516STimur Tabi * don't even want to get into that and try to implement the missing pieces in 3330a5462516STimur Tabi * the core. We really have other pieces to fix in the driver core mess. :) 3331a2de48caSGreg Kroah-Hartman */ 33326937e8f8SJohannes Berg int device_rename(struct device *dev, const char *new_name) 3333a2de48caSGreg Kroah-Hartman { 33344b30ee58STejun Heo struct kobject *kobj = &dev->kobj; 33352ee97cafSCornelia Huck char *old_device_name = NULL; 3336a2de48caSGreg Kroah-Hartman int error; 3337a2de48caSGreg Kroah-Hartman 3338a2de48caSGreg Kroah-Hartman dev = get_device(dev); 3339a2de48caSGreg Kroah-Hartman if (!dev) 3340a2de48caSGreg Kroah-Hartman return -EINVAL; 3341a2de48caSGreg Kroah-Hartman 334269df7533Sethan.zhao dev_dbg(dev, "renaming to %s\n", new_name); 3343a2de48caSGreg Kroah-Hartman 33441fa5ae85SKay Sievers old_device_name = kstrdup(dev_name(dev), GFP_KERNEL); 33452ee97cafSCornelia Huck if (!old_device_name) { 3346952ab431SJesper Juhl error = -ENOMEM; 33472ee97cafSCornelia Huck goto out; 3348952ab431SJesper Juhl } 3349a2de48caSGreg Kroah-Hartman 3350f349cf34SEric W. Biederman if (dev->class) { 33514b30ee58STejun Heo error = sysfs_rename_link_ns(&dev->class->p->subsys.kobj, 33524b30ee58STejun Heo kobj, old_device_name, 33534b30ee58STejun Heo new_name, kobject_namespace(kobj)); 3354f349cf34SEric W. Biederman if (error) 3355f349cf34SEric W. Biederman goto out; 3356f349cf34SEric W. Biederman } 335739aba963SKay Sievers 33584b30ee58STejun Heo error = kobject_rename(kobj, new_name); 33591fa5ae85SKay Sievers if (error) 33602ee97cafSCornelia Huck goto out; 3361a2de48caSGreg Kroah-Hartman 33622ee97cafSCornelia Huck out: 3363a2de48caSGreg Kroah-Hartman put_device(dev); 3364a2de48caSGreg Kroah-Hartman 33652ee97cafSCornelia Huck kfree(old_device_name); 3366a2de48caSGreg Kroah-Hartman 3367a2de48caSGreg Kroah-Hartman return error; 3368a2de48caSGreg Kroah-Hartman } 3369a2807dbcSJohannes Berg EXPORT_SYMBOL_GPL(device_rename); 33708a82472fSCornelia Huck 33718a82472fSCornelia Huck static int device_move_class_links(struct device *dev, 33728a82472fSCornelia Huck struct device *old_parent, 33738a82472fSCornelia Huck struct device *new_parent) 33748a82472fSCornelia Huck { 3375f7f3461dSGreg Kroah-Hartman int error = 0; 33768a82472fSCornelia Huck 3377f7f3461dSGreg Kroah-Hartman if (old_parent) 3378f7f3461dSGreg Kroah-Hartman sysfs_remove_link(&dev->kobj, "device"); 3379f7f3461dSGreg Kroah-Hartman if (new_parent) 3380f7f3461dSGreg Kroah-Hartman error = sysfs_create_link(&dev->kobj, &new_parent->kobj, 3381f7f3461dSGreg Kroah-Hartman "device"); 3382f7f3461dSGreg Kroah-Hartman return error; 33838a82472fSCornelia Huck } 33848a82472fSCornelia Huck 33858a82472fSCornelia Huck /** 33868a82472fSCornelia Huck * device_move - moves a device to a new parent 33878a82472fSCornelia Huck * @dev: the pointer to the struct device to be moved 338813509860SWolfram Sang * @new_parent: the new parent of the device (can be NULL) 3389ffa6a705SCornelia Huck * @dpm_order: how to reorder the dpm_list 33908a82472fSCornelia Huck */ 3391ffa6a705SCornelia Huck int device_move(struct device *dev, struct device *new_parent, 3392ffa6a705SCornelia Huck enum dpm_order dpm_order) 33938a82472fSCornelia Huck { 33948a82472fSCornelia Huck int error; 33958a82472fSCornelia Huck struct device *old_parent; 3396c744aeaeSCornelia Huck struct kobject *new_parent_kobj; 33978a82472fSCornelia Huck 33988a82472fSCornelia Huck dev = get_device(dev); 33998a82472fSCornelia Huck if (!dev) 34008a82472fSCornelia Huck return -EINVAL; 34018a82472fSCornelia Huck 3402ffa6a705SCornelia Huck device_pm_lock(); 34038a82472fSCornelia Huck new_parent = get_device(new_parent); 3404c744aeaeSCornelia Huck new_parent_kobj = get_device_parent(dev, new_parent); 340584d0c27dSTetsuo Handa if (IS_ERR(new_parent_kobj)) { 340684d0c27dSTetsuo Handa error = PTR_ERR(new_parent_kobj); 340784d0c27dSTetsuo Handa put_device(new_parent); 340884d0c27dSTetsuo Handa goto out; 340984d0c27dSTetsuo Handa } 341063b6971aSCornelia Huck 34111e0b2cf9SKay Sievers pr_debug("device: '%s': %s: moving to '%s'\n", dev_name(dev), 34121e0b2cf9SKay Sievers __func__, new_parent ? dev_name(new_parent) : "<NULL>"); 3413c744aeaeSCornelia Huck error = kobject_move(&dev->kobj, new_parent_kobj); 34148a82472fSCornelia Huck if (error) { 341563b6971aSCornelia Huck cleanup_glue_dir(dev, new_parent_kobj); 34168a82472fSCornelia Huck put_device(new_parent); 34178a82472fSCornelia Huck goto out; 34188a82472fSCornelia Huck } 34198a82472fSCornelia Huck old_parent = dev->parent; 34208a82472fSCornelia Huck dev->parent = new_parent; 34218a82472fSCornelia Huck if (old_parent) 3422f791b8c8SGreg Kroah-Hartman klist_remove(&dev->p->knode_parent); 34230d358f22SYinghai Lu if (new_parent) { 3424f791b8c8SGreg Kroah-Hartman klist_add_tail(&dev->p->knode_parent, 3425f791b8c8SGreg Kroah-Hartman &new_parent->p->klist_children); 34260d358f22SYinghai Lu set_dev_node(dev, dev_to_node(new_parent)); 34270d358f22SYinghai Lu } 34280d358f22SYinghai Lu 3429bdd4034dSRabin Vincent if (dev->class) { 34308a82472fSCornelia Huck error = device_move_class_links(dev, old_parent, new_parent); 34318a82472fSCornelia Huck if (error) { 34328a82472fSCornelia Huck /* We ignore errors on cleanup since we're hosed anyway... */ 34338a82472fSCornelia Huck device_move_class_links(dev, new_parent, old_parent); 34348a82472fSCornelia Huck if (!kobject_move(&dev->kobj, &old_parent->kobj)) { 3435c744aeaeSCornelia Huck if (new_parent) 3436f791b8c8SGreg Kroah-Hartman klist_remove(&dev->p->knode_parent); 34370d358f22SYinghai Lu dev->parent = old_parent; 34380d358f22SYinghai Lu if (old_parent) { 3439f791b8c8SGreg Kroah-Hartman klist_add_tail(&dev->p->knode_parent, 3440f791b8c8SGreg Kroah-Hartman &old_parent->p->klist_children); 34410d358f22SYinghai Lu set_dev_node(dev, dev_to_node(old_parent)); 34420d358f22SYinghai Lu } 34438a82472fSCornelia Huck } 344463b6971aSCornelia Huck cleanup_glue_dir(dev, new_parent_kobj); 34458a82472fSCornelia Huck put_device(new_parent); 34468a82472fSCornelia Huck goto out; 34478a82472fSCornelia Huck } 3448bdd4034dSRabin Vincent } 3449ffa6a705SCornelia Huck switch (dpm_order) { 3450ffa6a705SCornelia Huck case DPM_ORDER_NONE: 3451ffa6a705SCornelia Huck break; 3452ffa6a705SCornelia Huck case DPM_ORDER_DEV_AFTER_PARENT: 3453ffa6a705SCornelia Huck device_pm_move_after(dev, new_parent); 345452cdbdd4SGrygorii Strashko devices_kset_move_after(dev, new_parent); 3455ffa6a705SCornelia Huck break; 3456ffa6a705SCornelia Huck case DPM_ORDER_PARENT_BEFORE_DEV: 3457ffa6a705SCornelia Huck device_pm_move_before(new_parent, dev); 345852cdbdd4SGrygorii Strashko devices_kset_move_before(new_parent, dev); 3459ffa6a705SCornelia Huck break; 3460ffa6a705SCornelia Huck case DPM_ORDER_DEV_LAST: 3461ffa6a705SCornelia Huck device_pm_move_last(dev); 346252cdbdd4SGrygorii Strashko devices_kset_move_last(dev); 3463ffa6a705SCornelia Huck break; 3464ffa6a705SCornelia Huck } 3465bdd4034dSRabin Vincent 34668a82472fSCornelia Huck put_device(old_parent); 34678a82472fSCornelia Huck out: 3468ffa6a705SCornelia Huck device_pm_unlock(); 34698a82472fSCornelia Huck put_device(dev); 34708a82472fSCornelia Huck return error; 34718a82472fSCornelia Huck } 34728a82472fSCornelia Huck EXPORT_SYMBOL_GPL(device_move); 347337b0c020SGreg Kroah-Hartman 347437b0c020SGreg Kroah-Hartman /** 347537b0c020SGreg Kroah-Hartman * device_shutdown - call ->shutdown() on each device to shutdown. 347637b0c020SGreg Kroah-Hartman */ 347737b0c020SGreg Kroah-Hartman void device_shutdown(void) 347837b0c020SGreg Kroah-Hartman { 3479f123db8eSBenson Leung struct device *dev, *parent; 348037b0c020SGreg Kroah-Hartman 34813297c8fcSPingfan Liu wait_for_device_probe(); 34823297c8fcSPingfan Liu device_block_probing(); 34833297c8fcSPingfan Liu 348465650b35SRafael J. Wysocki cpufreq_suspend(); 348565650b35SRafael J. Wysocki 34866245838fSHugh Daschbach spin_lock(&devices_kset->list_lock); 34876245838fSHugh Daschbach /* 34886245838fSHugh Daschbach * Walk the devices list backward, shutting down each in turn. 34896245838fSHugh Daschbach * Beware that device unplug events may also start pulling 34906245838fSHugh Daschbach * devices offline, even as the system is shutting down. 34916245838fSHugh Daschbach */ 34926245838fSHugh Daschbach while (!list_empty(&devices_kset->list)) { 34936245838fSHugh Daschbach dev = list_entry(devices_kset->list.prev, struct device, 34946245838fSHugh Daschbach kobj.entry); 3495d1c6c030SMing Lei 3496d1c6c030SMing Lei /* 3497d1c6c030SMing Lei * hold reference count of device's parent to 3498d1c6c030SMing Lei * prevent it from being freed because parent's 3499d1c6c030SMing Lei * lock is to be held 3500d1c6c030SMing Lei */ 3501f123db8eSBenson Leung parent = get_device(dev->parent); 35026245838fSHugh Daschbach get_device(dev); 35036245838fSHugh Daschbach /* 35046245838fSHugh Daschbach * Make sure the device is off the kset list, in the 35056245838fSHugh Daschbach * event that dev->*->shutdown() doesn't remove it. 35066245838fSHugh Daschbach */ 35076245838fSHugh Daschbach list_del_init(&dev->kobj.entry); 35086245838fSHugh Daschbach spin_unlock(&devices_kset->list_lock); 3509fe6b91f4SAlan Stern 3510d1c6c030SMing Lei /* hold lock to avoid race with probe/release */ 3511f123db8eSBenson Leung if (parent) 3512f123db8eSBenson Leung device_lock(parent); 3513d1c6c030SMing Lei device_lock(dev); 3514d1c6c030SMing Lei 3515fe6b91f4SAlan Stern /* Don't allow any more runtime suspends */ 3516fe6b91f4SAlan Stern pm_runtime_get_noresume(dev); 3517fe6b91f4SAlan Stern pm_runtime_barrier(dev); 35186245838fSHugh Daschbach 35197521621eSMichal Suchanek if (dev->class && dev->class->shutdown_pre) { 3520f77af151SJosh Zimmerman if (initcall_debug) 35217521621eSMichal Suchanek dev_info(dev, "shutdown_pre\n"); 35227521621eSMichal Suchanek dev->class->shutdown_pre(dev); 35237521621eSMichal Suchanek } 35247521621eSMichal Suchanek if (dev->bus && dev->bus->shutdown) { 35250246c4faSShuoX Liu if (initcall_debug) 35260246c4faSShuoX Liu dev_info(dev, "shutdown\n"); 352737b0c020SGreg Kroah-Hartman dev->bus->shutdown(dev); 352837b0c020SGreg Kroah-Hartman } else if (dev->driver && dev->driver->shutdown) { 35290246c4faSShuoX Liu if (initcall_debug) 35300246c4faSShuoX Liu dev_info(dev, "shutdown\n"); 353137b0c020SGreg Kroah-Hartman dev->driver->shutdown(dev); 353237b0c020SGreg Kroah-Hartman } 3533d1c6c030SMing Lei 3534d1c6c030SMing Lei device_unlock(dev); 3535f123db8eSBenson Leung if (parent) 3536f123db8eSBenson Leung device_unlock(parent); 3537d1c6c030SMing Lei 35386245838fSHugh Daschbach put_device(dev); 3539f123db8eSBenson Leung put_device(parent); 35406245838fSHugh Daschbach 35416245838fSHugh Daschbach spin_lock(&devices_kset->list_lock); 354237b0c020SGreg Kroah-Hartman } 35436245838fSHugh Daschbach spin_unlock(&devices_kset->list_lock); 354437b0c020SGreg Kroah-Hartman } 354599bcf217SJoe Perches 354699bcf217SJoe Perches /* 354799bcf217SJoe Perches * Device logging functions 354899bcf217SJoe Perches */ 354999bcf217SJoe Perches 355099bcf217SJoe Perches #ifdef CONFIG_PRINTK 3551666f355fSJoe Perches static int 3552666f355fSJoe Perches create_syslog_header(const struct device *dev, char *hdr, size_t hdrlen) 355399bcf217SJoe Perches { 3554c4e00daaSKay Sievers const char *subsys; 3555798efc60SJoe Perches size_t pos = 0; 355699bcf217SJoe Perches 3557c4e00daaSKay Sievers if (dev->class) 3558c4e00daaSKay Sievers subsys = dev->class->name; 3559c4e00daaSKay Sievers else if (dev->bus) 3560c4e00daaSKay Sievers subsys = dev->bus->name; 3561c4e00daaSKay Sievers else 3562798efc60SJoe Perches return 0; 3563c4e00daaSKay Sievers 3564798efc60SJoe Perches pos += snprintf(hdr + pos, hdrlen - pos, "SUBSYSTEM=%s", subsys); 3565655e5b7cSBen Hutchings if (pos >= hdrlen) 3566655e5b7cSBen Hutchings goto overflow; 3567c4e00daaSKay Sievers 3568c4e00daaSKay Sievers /* 3569c4e00daaSKay Sievers * Add device identifier DEVICE=: 3570c4e00daaSKay Sievers * b12:8 block dev_t 3571c4e00daaSKay Sievers * c127:3 char dev_t 3572c4e00daaSKay Sievers * n8 netdev ifindex 3573c4e00daaSKay Sievers * +sound:card0 subsystem:devname 3574c4e00daaSKay Sievers */ 3575c4e00daaSKay Sievers if (MAJOR(dev->devt)) { 3576c4e00daaSKay Sievers char c; 3577c4e00daaSKay Sievers 3578c4e00daaSKay Sievers if (strcmp(subsys, "block") == 0) 3579c4e00daaSKay Sievers c = 'b'; 3580c4e00daaSKay Sievers else 3581c4e00daaSKay Sievers c = 'c'; 3582798efc60SJoe Perches pos++; 3583798efc60SJoe Perches pos += snprintf(hdr + pos, hdrlen - pos, 3584c4e00daaSKay Sievers "DEVICE=%c%u:%u", 3585c4e00daaSKay Sievers c, MAJOR(dev->devt), MINOR(dev->devt)); 3586c4e00daaSKay Sievers } else if (strcmp(subsys, "net") == 0) { 3587c4e00daaSKay Sievers struct net_device *net = to_net_dev(dev); 3588c4e00daaSKay Sievers 3589798efc60SJoe Perches pos++; 3590798efc60SJoe Perches pos += snprintf(hdr + pos, hdrlen - pos, 3591c4e00daaSKay Sievers "DEVICE=n%u", net->ifindex); 3592c4e00daaSKay Sievers } else { 3593798efc60SJoe Perches pos++; 3594798efc60SJoe Perches pos += snprintf(hdr + pos, hdrlen - pos, 3595c4e00daaSKay Sievers "DEVICE=+%s:%s", subsys, dev_name(dev)); 3596c4e00daaSKay Sievers } 3597af7f2158SJim Cromie 3598655e5b7cSBen Hutchings if (pos >= hdrlen) 3599655e5b7cSBen Hutchings goto overflow; 3600655e5b7cSBen Hutchings 3601798efc60SJoe Perches return pos; 3602655e5b7cSBen Hutchings 3603655e5b7cSBen Hutchings overflow: 3604655e5b7cSBen Hutchings dev_WARN(dev, "device/subsystem name too long"); 3605655e5b7cSBen Hutchings return 0; 360699bcf217SJoe Perches } 3607798efc60SJoe Perches 360805e4e5b8SJoe Perches int dev_vprintk_emit(int level, const struct device *dev, 360905e4e5b8SJoe Perches const char *fmt, va_list args) 361005e4e5b8SJoe Perches { 361105e4e5b8SJoe Perches char hdr[128]; 361205e4e5b8SJoe Perches size_t hdrlen; 361305e4e5b8SJoe Perches 361405e4e5b8SJoe Perches hdrlen = create_syslog_header(dev, hdr, sizeof(hdr)); 361505e4e5b8SJoe Perches 361605e4e5b8SJoe Perches return vprintk_emit(0, level, hdrlen ? hdr : NULL, hdrlen, fmt, args); 361705e4e5b8SJoe Perches } 361805e4e5b8SJoe Perches EXPORT_SYMBOL(dev_vprintk_emit); 361905e4e5b8SJoe Perches 362005e4e5b8SJoe Perches int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...) 362105e4e5b8SJoe Perches { 362205e4e5b8SJoe Perches va_list args; 362305e4e5b8SJoe Perches int r; 362405e4e5b8SJoe Perches 362505e4e5b8SJoe Perches va_start(args, fmt); 362605e4e5b8SJoe Perches 362705e4e5b8SJoe Perches r = dev_vprintk_emit(level, dev, fmt, args); 362805e4e5b8SJoe Perches 362905e4e5b8SJoe Perches va_end(args); 363005e4e5b8SJoe Perches 363105e4e5b8SJoe Perches return r; 363205e4e5b8SJoe Perches } 363305e4e5b8SJoe Perches EXPORT_SYMBOL(dev_printk_emit); 363405e4e5b8SJoe Perches 3635d1f1052cSJoe Perches static void __dev_printk(const char *level, const struct device *dev, 3636798efc60SJoe Perches struct va_format *vaf) 3637798efc60SJoe Perches { 3638d1f1052cSJoe Perches if (dev) 3639d1f1052cSJoe Perches dev_printk_emit(level[1] - '0', dev, "%s %s: %pV", 3640798efc60SJoe Perches dev_driver_string(dev), dev_name(dev), vaf); 3641d1f1052cSJoe Perches else 3642d1f1052cSJoe Perches printk("%s(NULL device *): %pV", level, vaf); 3643798efc60SJoe Perches } 364499bcf217SJoe Perches 3645d1f1052cSJoe Perches void dev_printk(const char *level, const struct device *dev, 364699bcf217SJoe Perches const char *fmt, ...) 364799bcf217SJoe Perches { 364899bcf217SJoe Perches struct va_format vaf; 364999bcf217SJoe Perches va_list args; 365099bcf217SJoe Perches 365199bcf217SJoe Perches va_start(args, fmt); 365299bcf217SJoe Perches 365399bcf217SJoe Perches vaf.fmt = fmt; 365499bcf217SJoe Perches vaf.va = &args; 365599bcf217SJoe Perches 3656d1f1052cSJoe Perches __dev_printk(level, dev, &vaf); 3657798efc60SJoe Perches 365899bcf217SJoe Perches va_end(args); 365999bcf217SJoe Perches } 366099bcf217SJoe Perches EXPORT_SYMBOL(dev_printk); 366199bcf217SJoe Perches 366299bcf217SJoe Perches #define define_dev_printk_level(func, kern_level) \ 3663d1f1052cSJoe Perches void func(const struct device *dev, const char *fmt, ...) \ 366499bcf217SJoe Perches { \ 366599bcf217SJoe Perches struct va_format vaf; \ 366699bcf217SJoe Perches va_list args; \ 366799bcf217SJoe Perches \ 366899bcf217SJoe Perches va_start(args, fmt); \ 366999bcf217SJoe Perches \ 367099bcf217SJoe Perches vaf.fmt = fmt; \ 367199bcf217SJoe Perches vaf.va = &args; \ 367299bcf217SJoe Perches \ 3673d1f1052cSJoe Perches __dev_printk(kern_level, dev, &vaf); \ 3674798efc60SJoe Perches \ 367599bcf217SJoe Perches va_end(args); \ 367699bcf217SJoe Perches } \ 367799bcf217SJoe Perches EXPORT_SYMBOL(func); 367899bcf217SJoe Perches 3679663336eeSJoe Perches define_dev_printk_level(_dev_emerg, KERN_EMERG); 3680663336eeSJoe Perches define_dev_printk_level(_dev_alert, KERN_ALERT); 3681663336eeSJoe Perches define_dev_printk_level(_dev_crit, KERN_CRIT); 3682663336eeSJoe Perches define_dev_printk_level(_dev_err, KERN_ERR); 3683663336eeSJoe Perches define_dev_printk_level(_dev_warn, KERN_WARNING); 3684663336eeSJoe Perches define_dev_printk_level(_dev_notice, KERN_NOTICE); 368599bcf217SJoe Perches define_dev_printk_level(_dev_info, KERN_INFO); 368699bcf217SJoe Perches 368799bcf217SJoe Perches #endif 368897badf87SRafael J. Wysocki 368997badf87SRafael J. Wysocki static inline bool fwnode_is_primary(struct fwnode_handle *fwnode) 369097badf87SRafael J. Wysocki { 369197badf87SRafael J. Wysocki return fwnode && !IS_ERR(fwnode->secondary); 369297badf87SRafael J. Wysocki } 369397badf87SRafael J. Wysocki 369497badf87SRafael J. Wysocki /** 369597badf87SRafael J. Wysocki * set_primary_fwnode - Change the primary firmware node of a given device. 369697badf87SRafael J. Wysocki * @dev: Device to handle. 369797badf87SRafael J. Wysocki * @fwnode: New primary firmware node of the device. 369897badf87SRafael J. Wysocki * 369997badf87SRafael J. Wysocki * Set the device's firmware node pointer to @fwnode, but if a secondary 370097badf87SRafael J. Wysocki * firmware node of the device is present, preserve it. 370197badf87SRafael J. Wysocki */ 370297badf87SRafael J. Wysocki void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode) 370397badf87SRafael J. Wysocki { 370497badf87SRafael J. Wysocki if (fwnode) { 370597badf87SRafael J. Wysocki struct fwnode_handle *fn = dev->fwnode; 370697badf87SRafael J. Wysocki 370797badf87SRafael J. Wysocki if (fwnode_is_primary(fn)) 370897badf87SRafael J. Wysocki fn = fn->secondary; 370997badf87SRafael J. Wysocki 371055f89a8aSMika Westerberg if (fn) { 371155f89a8aSMika Westerberg WARN_ON(fwnode->secondary); 371297badf87SRafael J. Wysocki fwnode->secondary = fn; 371355f89a8aSMika Westerberg } 371497badf87SRafael J. Wysocki dev->fwnode = fwnode; 371597badf87SRafael J. Wysocki } else { 371697badf87SRafael J. Wysocki dev->fwnode = fwnode_is_primary(dev->fwnode) ? 371797badf87SRafael J. Wysocki dev->fwnode->secondary : NULL; 371897badf87SRafael J. Wysocki } 371997badf87SRafael J. Wysocki } 372097badf87SRafael J. Wysocki EXPORT_SYMBOL_GPL(set_primary_fwnode); 372197badf87SRafael J. Wysocki 372297badf87SRafael J. Wysocki /** 372397badf87SRafael J. Wysocki * set_secondary_fwnode - Change the secondary firmware node of a given device. 372497badf87SRafael J. Wysocki * @dev: Device to handle. 372597badf87SRafael J. Wysocki * @fwnode: New secondary firmware node of the device. 372697badf87SRafael J. Wysocki * 372797badf87SRafael J. Wysocki * If a primary firmware node of the device is present, set its secondary 372897badf87SRafael J. Wysocki * pointer to @fwnode. Otherwise, set the device's firmware node pointer to 372997badf87SRafael J. Wysocki * @fwnode. 373097badf87SRafael J. Wysocki */ 373197badf87SRafael J. Wysocki void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode) 373297badf87SRafael J. Wysocki { 373397badf87SRafael J. Wysocki if (fwnode) 373497badf87SRafael J. Wysocki fwnode->secondary = ERR_PTR(-ENODEV); 373597badf87SRafael J. Wysocki 373697badf87SRafael J. Wysocki if (fwnode_is_primary(dev->fwnode)) 373797badf87SRafael J. Wysocki dev->fwnode->secondary = fwnode; 373897badf87SRafael J. Wysocki else 373997badf87SRafael J. Wysocki dev->fwnode = fwnode; 374097badf87SRafael J. Wysocki } 37414e75e1d7SJohan Hovold 37424e75e1d7SJohan Hovold /** 37434e75e1d7SJohan Hovold * device_set_of_node_from_dev - reuse device-tree node of another device 37444e75e1d7SJohan Hovold * @dev: device whose device-tree node is being set 37454e75e1d7SJohan Hovold * @dev2: device whose device-tree node is being reused 37464e75e1d7SJohan Hovold * 37474e75e1d7SJohan Hovold * Takes another reference to the new device-tree node after first dropping 37484e75e1d7SJohan Hovold * any reference held to the old node. 37494e75e1d7SJohan Hovold */ 37504e75e1d7SJohan Hovold void device_set_of_node_from_dev(struct device *dev, const struct device *dev2) 37514e75e1d7SJohan Hovold { 37524e75e1d7SJohan Hovold of_node_put(dev->of_node); 37534e75e1d7SJohan Hovold dev->of_node = of_node_get(dev2->of_node); 37544e75e1d7SJohan Hovold dev->of_node_reused = true; 37554e75e1d7SJohan Hovold } 37564e75e1d7SJohan Hovold EXPORT_SYMBOL_GPL(device_set_of_node_from_dev); 375765b66682SSuzuki K Poulose 37586cda08a2SSuzuki K Poulose int device_match_name(struct device *dev, const void *name) 37596cda08a2SSuzuki K Poulose { 37606cda08a2SSuzuki K Poulose return sysfs_streq(dev_name(dev), name); 37616cda08a2SSuzuki K Poulose } 37626cda08a2SSuzuki K Poulose EXPORT_SYMBOL_GPL(device_match_name); 37636cda08a2SSuzuki K Poulose 376465b66682SSuzuki K Poulose int device_match_of_node(struct device *dev, const void *np) 376565b66682SSuzuki K Poulose { 376665b66682SSuzuki K Poulose return dev->of_node == np; 376765b66682SSuzuki K Poulose } 376865b66682SSuzuki K Poulose EXPORT_SYMBOL_GPL(device_match_of_node); 376967843bbaSSuzuki K Poulose 377067843bbaSSuzuki K Poulose int device_match_fwnode(struct device *dev, const void *fwnode) 377167843bbaSSuzuki K Poulose { 377267843bbaSSuzuki K Poulose return dev_fwnode(dev) == fwnode; 377367843bbaSSuzuki K Poulose } 377467843bbaSSuzuki K Poulose EXPORT_SYMBOL_GPL(device_match_fwnode); 37754495dfddSSuzuki K Poulose 37764495dfddSSuzuki K Poulose int device_match_devt(struct device *dev, const void *pdevt) 37774495dfddSSuzuki K Poulose { 37784495dfddSSuzuki K Poulose return dev->devt == *(dev_t *)pdevt; 37794495dfddSSuzuki K Poulose } 37804495dfddSSuzuki K Poulose EXPORT_SYMBOL_GPL(device_match_devt); 378100500147SSuzuki K Poulose 378200500147SSuzuki K Poulose int device_match_acpi_dev(struct device *dev, const void *adev) 378300500147SSuzuki K Poulose { 378400500147SSuzuki K Poulose return ACPI_COMPANION(dev) == adev; 378500500147SSuzuki K Poulose } 378600500147SSuzuki K Poulose EXPORT_SYMBOL(device_match_acpi_dev); 37876bf85ba9SSuzuki K Poulose 37886bf85ba9SSuzuki K Poulose int device_match_any(struct device *dev, const void *unused) 37896bf85ba9SSuzuki K Poulose { 37906bf85ba9SSuzuki K Poulose return 1; 37916bf85ba9SSuzuki K Poulose } 37926bf85ba9SSuzuki K Poulose EXPORT_SYMBOL_GPL(device_match_any); 3793