1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * device.h - generic, centralized driver model
4 *
5 * Copyright (c) 2001-2003 Patrick Mochel <mochel@osdl.org>
6 * Copyright (c) 2004-2009 Greg Kroah-Hartman <gregkh@suse.de>
7 * Copyright (c) 2008-2009 Novell Inc.
8 *
9 * See Documentation/driver-api/driver-model/ for more information.
10 */
11
12 #ifndef _DEVICE_H_
13 #define _DEVICE_H_
14
15 #include <linux/dev_printk.h>
16 #include <linux/energy_model.h>
17 #include <linux/ioport.h>
18 #include <linux/kobject.h>
19 #include <linux/klist.h>
20 #include <linux/list.h>
21 #include <linux/lockdep.h>
22 #include <linux/compiler.h>
23 #include <linux/types.h>
24 #include <linux/mutex.h>
25 #include <linux/pm.h>
26 #include <linux/atomic.h>
27 #include <linux/uidgid.h>
28 #include <linux/gfp.h>
29 #include <linux/overflow.h>
30 #include <linux/device/bus.h>
31 #include <linux/device/class.h>
32 #include <linux/device/driver.h>
33 #include <linux/cleanup.h>
34 #include <asm/device.h>
35
36 struct device;
37 struct device_private;
38 struct device_driver;
39 struct driver_private;
40 struct module;
41 struct class;
42 struct subsys_private;
43 struct device_node;
44 struct fwnode_handle;
45 struct iommu_ops;
46 struct iommu_group;
47 struct dev_pin_info;
48 struct dev_iommu;
49 struct msi_device_data;
50
51 /**
52 * struct subsys_interface - interfaces to device functions
53 * @name: name of the device function
54 * @subsys: subsystem of the devices to attach to
55 * @node: the list of functions registered at the subsystem
56 * @add_dev: device hookup to device function handler
57 * @remove_dev: device hookup to device function handler
58 *
59 * Simple interfaces attached to a subsystem. Multiple interfaces can
60 * attach to a subsystem and its devices. Unlike drivers, they do not
61 * exclusively claim or control devices. Interfaces usually represent
62 * a specific functionality of a subsystem/class of devices.
63 */
64 struct subsys_interface {
65 const char *name;
66 struct bus_type *subsys;
67 struct list_head node;
68 int (*add_dev)(struct device *dev, struct subsys_interface *sif);
69 void (*remove_dev)(struct device *dev, struct subsys_interface *sif);
70 };
71
72 int subsys_interface_register(struct subsys_interface *sif);
73 void subsys_interface_unregister(struct subsys_interface *sif);
74
75 int subsys_system_register(struct bus_type *subsys,
76 const struct attribute_group **groups);
77 int subsys_virtual_register(struct bus_type *subsys,
78 const struct attribute_group **groups);
79
80 /*
81 * The type of device, "struct device" is embedded in. A class
82 * or bus can contain devices of different types
83 * like "partitions" and "disks", "mouse" and "event".
84 * This identifies the device type and carries type-specific
85 * information, equivalent to the kobj_type of a kobject.
86 * If "name" is specified, the uevent will contain it in
87 * the DEVTYPE variable.
88 */
89 struct device_type {
90 const char *name;
91 const struct attribute_group **groups;
92 int (*uevent)(const struct device *dev, struct kobj_uevent_env *env);
93 char *(*devnode)(const struct device *dev, umode_t *mode,
94 kuid_t *uid, kgid_t *gid);
95 void (*release)(struct device *dev);
96
97 const struct dev_pm_ops *pm;
98 };
99
100 /**
101 * struct device_attribute - Interface for exporting device attributes.
102 * @attr: sysfs attribute definition.
103 * @show: Show handler.
104 * @store: Store handler.
105 */
106 struct device_attribute {
107 struct attribute attr;
108 ssize_t (*show)(struct device *dev, struct device_attribute *attr,
109 char *buf);
110 ssize_t (*store)(struct device *dev, struct device_attribute *attr,
111 const char *buf, size_t count);
112 };
113
114 /**
115 * struct dev_ext_attribute - Exported device attribute with extra context.
116 * @attr: Exported device attribute.
117 * @var: Pointer to context.
118 */
119 struct dev_ext_attribute {
120 struct device_attribute attr;
121 void *var;
122 };
123
124 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
125 char *buf);
126 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
127 const char *buf, size_t count);
128 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
129 char *buf);
130 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
131 const char *buf, size_t count);
132 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
133 char *buf);
134 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
135 const char *buf, size_t count);
136
137 /**
138 * DEVICE_ATTR - Define a device attribute.
139 * @_name: Attribute name.
140 * @_mode: File mode.
141 * @_show: Show handler. Optional, but mandatory if attribute is readable.
142 * @_store: Store handler. Optional, but mandatory if attribute is writable.
143 *
144 * Convenience macro for defining a struct device_attribute.
145 *
146 * For example, ``DEVICE_ATTR(foo, 0644, foo_show, foo_store);`` expands to:
147 *
148 * .. code-block:: c
149 *
150 * struct device_attribute dev_attr_foo = {
151 * .attr = { .name = "foo", .mode = 0644 },
152 * .show = foo_show,
153 * .store = foo_store,
154 * };
155 */
156 #define DEVICE_ATTR(_name, _mode, _show, _store) \
157 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
158
159 /**
160 * DEVICE_ATTR_PREALLOC - Define a preallocated device attribute.
161 * @_name: Attribute name.
162 * @_mode: File mode.
163 * @_show: Show handler. Optional, but mandatory if attribute is readable.
164 * @_store: Store handler. Optional, but mandatory if attribute is writable.
165 *
166 * Like DEVICE_ATTR(), but ``SYSFS_PREALLOC`` is set on @_mode.
167 */
168 #define DEVICE_ATTR_PREALLOC(_name, _mode, _show, _store) \
169 struct device_attribute dev_attr_##_name = \
170 __ATTR_PREALLOC(_name, _mode, _show, _store)
171
172 /**
173 * DEVICE_ATTR_RW - Define a read-write device attribute.
174 * @_name: Attribute name.
175 *
176 * Like DEVICE_ATTR(), but @_mode is 0644, @_show is <_name>_show,
177 * and @_store is <_name>_store.
178 */
179 #define DEVICE_ATTR_RW(_name) \
180 struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
181
182 /**
183 * DEVICE_ATTR_ADMIN_RW - Define an admin-only read-write device attribute.
184 * @_name: Attribute name.
185 *
186 * Like DEVICE_ATTR_RW(), but @_mode is 0600.
187 */
188 #define DEVICE_ATTR_ADMIN_RW(_name) \
189 struct device_attribute dev_attr_##_name = __ATTR_RW_MODE(_name, 0600)
190
191 /**
192 * DEVICE_ATTR_RO - Define a readable device attribute.
193 * @_name: Attribute name.
194 *
195 * Like DEVICE_ATTR(), but @_mode is 0444 and @_show is <_name>_show.
196 */
197 #define DEVICE_ATTR_RO(_name) \
198 struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
199
200 /**
201 * DEVICE_ATTR_ADMIN_RO - Define an admin-only readable device attribute.
202 * @_name: Attribute name.
203 *
204 * Like DEVICE_ATTR_RO(), but @_mode is 0400.
205 */
206 #define DEVICE_ATTR_ADMIN_RO(_name) \
207 struct device_attribute dev_attr_##_name = __ATTR_RO_MODE(_name, 0400)
208
209 /**
210 * DEVICE_ATTR_WO - Define an admin-only writable device attribute.
211 * @_name: Attribute name.
212 *
213 * Like DEVICE_ATTR(), but @_mode is 0200 and @_store is <_name>_store.
214 */
215 #define DEVICE_ATTR_WO(_name) \
216 struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
217
218 /**
219 * DEVICE_ULONG_ATTR - Define a device attribute backed by an unsigned long.
220 * @_name: Attribute name.
221 * @_mode: File mode.
222 * @_var: Identifier of unsigned long.
223 *
224 * Like DEVICE_ATTR(), but @_show and @_store are automatically provided
225 * such that reads and writes to the attribute from userspace affect @_var.
226 */
227 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
228 struct dev_ext_attribute dev_attr_##_name = \
229 { __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
230
231 /**
232 * DEVICE_INT_ATTR - Define a device attribute backed by an int.
233 * @_name: Attribute name.
234 * @_mode: File mode.
235 * @_var: Identifier of int.
236 *
237 * Like DEVICE_ULONG_ATTR(), but @_var is an int.
238 */
239 #define DEVICE_INT_ATTR(_name, _mode, _var) \
240 struct dev_ext_attribute dev_attr_##_name = \
241 { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
242
243 /**
244 * DEVICE_BOOL_ATTR - Define a device attribute backed by a bool.
245 * @_name: Attribute name.
246 * @_mode: File mode.
247 * @_var: Identifier of bool.
248 *
249 * Like DEVICE_ULONG_ATTR(), but @_var is a bool.
250 */
251 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
252 struct dev_ext_attribute dev_attr_##_name = \
253 { __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
254
255 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
256 struct device_attribute dev_attr_##_name = \
257 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
258
259 int device_create_file(struct device *device,
260 const struct device_attribute *entry);
261 void device_remove_file(struct device *dev,
262 const struct device_attribute *attr);
263 bool device_remove_file_self(struct device *dev,
264 const struct device_attribute *attr);
265 int __must_check device_create_bin_file(struct device *dev,
266 const struct bin_attribute *attr);
267 void device_remove_bin_file(struct device *dev,
268 const struct bin_attribute *attr);
269
270 /* device resource management */
271 typedef void (*dr_release_t)(struct device *dev, void *res);
272 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
273
274 void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
275 int nid, const char *name) __malloc;
276 #define devres_alloc(release, size, gfp) \
277 __devres_alloc_node(release, size, gfp, NUMA_NO_NODE, #release)
278 #define devres_alloc_node(release, size, gfp, nid) \
279 __devres_alloc_node(release, size, gfp, nid, #release)
280
281 void devres_for_each_res(struct device *dev, dr_release_t release,
282 dr_match_t match, void *match_data,
283 void (*fn)(struct device *, void *, void *),
284 void *data);
285 void devres_free(void *res);
286 void devres_add(struct device *dev, void *res);
287 void *devres_find(struct device *dev, dr_release_t release,
288 dr_match_t match, void *match_data);
289 void *devres_get(struct device *dev, void *new_res,
290 dr_match_t match, void *match_data);
291 void *devres_remove(struct device *dev, dr_release_t release,
292 dr_match_t match, void *match_data);
293 int devres_destroy(struct device *dev, dr_release_t release,
294 dr_match_t match, void *match_data);
295 int devres_release(struct device *dev, dr_release_t release,
296 dr_match_t match, void *match_data);
297
298 /* devres group */
299 void * __must_check devres_open_group(struct device *dev, void *id, gfp_t gfp);
300 void devres_close_group(struct device *dev, void *id);
301 void devres_remove_group(struct device *dev, void *id);
302 int devres_release_group(struct device *dev, void *id);
303
304 /* managed devm_k.alloc/kfree for device drivers */
305 void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __alloc_size(2);
306 void *devm_krealloc(struct device *dev, void *ptr, size_t size,
307 gfp_t gfp) __must_check __realloc_size(3);
308 __printf(3, 0) char *devm_kvasprintf(struct device *dev, gfp_t gfp,
309 const char *fmt, va_list ap) __malloc;
310 __printf(3, 4) char *devm_kasprintf(struct device *dev, gfp_t gfp,
311 const char *fmt, ...) __malloc;
devm_kzalloc(struct device * dev,size_t size,gfp_t gfp)312 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
313 {
314 return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
315 }
devm_kmalloc_array(struct device * dev,size_t n,size_t size,gfp_t flags)316 static inline void *devm_kmalloc_array(struct device *dev,
317 size_t n, size_t size, gfp_t flags)
318 {
319 size_t bytes;
320
321 if (unlikely(check_mul_overflow(n, size, &bytes)))
322 return NULL;
323
324 return devm_kmalloc(dev, bytes, flags);
325 }
devm_kcalloc(struct device * dev,size_t n,size_t size,gfp_t flags)326 static inline void *devm_kcalloc(struct device *dev,
327 size_t n, size_t size, gfp_t flags)
328 {
329 return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
330 }
331 static inline __realloc_size(3, 4) void * __must_check
devm_krealloc_array(struct device * dev,void * p,size_t new_n,size_t new_size,gfp_t flags)332 devm_krealloc_array(struct device *dev, void *p, size_t new_n, size_t new_size, gfp_t flags)
333 {
334 size_t bytes;
335
336 if (unlikely(check_mul_overflow(new_n, new_size, &bytes)))
337 return NULL;
338
339 return devm_krealloc(dev, p, bytes, flags);
340 }
341
342 void devm_kfree(struct device *dev, const void *p);
343 char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
344 const char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp);
345 void *devm_kmemdup(struct device *dev, const void *src, size_t len, gfp_t gfp)
346 __realloc_size(3);
347
348 unsigned long devm_get_free_pages(struct device *dev,
349 gfp_t gfp_mask, unsigned int order);
350 void devm_free_pages(struct device *dev, unsigned long addr);
351
352 #ifdef CONFIG_HAS_IOMEM
353 void __iomem *devm_ioremap_resource(struct device *dev,
354 const struct resource *res);
355 void __iomem *devm_ioremap_resource_wc(struct device *dev,
356 const struct resource *res);
357
358 void __iomem *devm_of_iomap(struct device *dev,
359 struct device_node *node, int index,
360 resource_size_t *size);
361 #else
362
363 static inline
devm_ioremap_resource(struct device * dev,const struct resource * res)364 void __iomem *devm_ioremap_resource(struct device *dev,
365 const struct resource *res)
366 {
367 return ERR_PTR(-EINVAL);
368 }
369
370 static inline
devm_ioremap_resource_wc(struct device * dev,const struct resource * res)371 void __iomem *devm_ioremap_resource_wc(struct device *dev,
372 const struct resource *res)
373 {
374 return ERR_PTR(-EINVAL);
375 }
376
377 static inline
devm_of_iomap(struct device * dev,struct device_node * node,int index,resource_size_t * size)378 void __iomem *devm_of_iomap(struct device *dev,
379 struct device_node *node, int index,
380 resource_size_t *size)
381 {
382 return ERR_PTR(-EINVAL);
383 }
384
385 #endif
386
387 /* allows to add/remove a custom action to devres stack */
388 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
389 void devm_release_action(struct device *dev, void (*action)(void *), void *data);
390
391 int __devm_add_action(struct device *dev, void (*action)(void *), void *data, const char *name);
392 #define devm_add_action(release, action, data) \
393 __devm_add_action(release, action, data, #action)
394
__devm_add_action_or_reset(struct device * dev,void (* action)(void *),void * data,const char * name)395 static inline int __devm_add_action_or_reset(struct device *dev, void (*action)(void *),
396 void *data, const char *name)
397 {
398 int ret;
399
400 ret = __devm_add_action(dev, action, data, name);
401 if (ret)
402 action(data);
403
404 return ret;
405 }
406 #define devm_add_action_or_reset(release, action, data) \
407 __devm_add_action_or_reset(release, action, data, #action)
408
409 /**
410 * devm_alloc_percpu - Resource-managed alloc_percpu
411 * @dev: Device to allocate per-cpu memory for
412 * @type: Type to allocate per-cpu memory for
413 *
414 * Managed alloc_percpu. Per-cpu memory allocated with this function is
415 * automatically freed on driver detach.
416 *
417 * RETURNS:
418 * Pointer to allocated memory on success, NULL on failure.
419 */
420 #define devm_alloc_percpu(dev, type) \
421 ((typeof(type) __percpu *)__devm_alloc_percpu((dev), sizeof(type), \
422 __alignof__(type)))
423
424 void __percpu *__devm_alloc_percpu(struct device *dev, size_t size,
425 size_t align);
426 void devm_free_percpu(struct device *dev, void __percpu *pdata);
427
428 struct device_dma_parameters {
429 /*
430 * a low level driver may set these to teach IOMMU code about
431 * sg limitations.
432 */
433 unsigned int max_segment_size;
434 unsigned int min_align_mask;
435 unsigned long segment_boundary_mask;
436 };
437
438 /**
439 * enum device_link_state - Device link states.
440 * @DL_STATE_NONE: The presence of the drivers is not being tracked.
441 * @DL_STATE_DORMANT: None of the supplier/consumer drivers is present.
442 * @DL_STATE_AVAILABLE: The supplier driver is present, but the consumer is not.
443 * @DL_STATE_CONSUMER_PROBE: The consumer is probing (supplier driver present).
444 * @DL_STATE_ACTIVE: Both the supplier and consumer drivers are present.
445 * @DL_STATE_SUPPLIER_UNBIND: The supplier driver is unbinding.
446 */
447 enum device_link_state {
448 DL_STATE_NONE = -1,
449 DL_STATE_DORMANT = 0,
450 DL_STATE_AVAILABLE,
451 DL_STATE_CONSUMER_PROBE,
452 DL_STATE_ACTIVE,
453 DL_STATE_SUPPLIER_UNBIND,
454 };
455
456 /*
457 * Device link flags.
458 *
459 * STATELESS: The core will not remove this link automatically.
460 * AUTOREMOVE_CONSUMER: Remove the link automatically on consumer driver unbind.
461 * PM_RUNTIME: If set, the runtime PM framework will use this link.
462 * RPM_ACTIVE: Run pm_runtime_get_sync() on the supplier during link creation.
463 * AUTOREMOVE_SUPPLIER: Remove the link automatically on supplier driver unbind.
464 * AUTOPROBE_CONSUMER: Probe consumer driver automatically after supplier binds.
465 * MANAGED: The core tracks presence of supplier/consumer drivers (internal).
466 * SYNC_STATE_ONLY: Link only affects sync_state() behavior.
467 * INFERRED: Inferred from data (eg: firmware) and not from driver actions.
468 */
469 #define DL_FLAG_STATELESS BIT(0)
470 #define DL_FLAG_AUTOREMOVE_CONSUMER BIT(1)
471 #define DL_FLAG_PM_RUNTIME BIT(2)
472 #define DL_FLAG_RPM_ACTIVE BIT(3)
473 #define DL_FLAG_AUTOREMOVE_SUPPLIER BIT(4)
474 #define DL_FLAG_AUTOPROBE_CONSUMER BIT(5)
475 #define DL_FLAG_MANAGED BIT(6)
476 #define DL_FLAG_SYNC_STATE_ONLY BIT(7)
477 #define DL_FLAG_INFERRED BIT(8)
478 #define DL_FLAG_CYCLE BIT(9)
479
480 /**
481 * enum dl_dev_state - Device driver presence tracking information.
482 * @DL_DEV_NO_DRIVER: There is no driver attached to the device.
483 * @DL_DEV_PROBING: A driver is probing.
484 * @DL_DEV_DRIVER_BOUND: The driver has been bound to the device.
485 * @DL_DEV_UNBINDING: The driver is unbinding from the device.
486 */
487 enum dl_dev_state {
488 DL_DEV_NO_DRIVER = 0,
489 DL_DEV_PROBING,
490 DL_DEV_DRIVER_BOUND,
491 DL_DEV_UNBINDING,
492 };
493
494 /**
495 * enum device_removable - Whether the device is removable. The criteria for a
496 * device to be classified as removable is determined by its subsystem or bus.
497 * @DEVICE_REMOVABLE_NOT_SUPPORTED: This attribute is not supported for this
498 * device (default).
499 * @DEVICE_REMOVABLE_UNKNOWN: Device location is Unknown.
500 * @DEVICE_FIXED: Device is not removable by the user.
501 * @DEVICE_REMOVABLE: Device is removable by the user.
502 */
503 enum device_removable {
504 DEVICE_REMOVABLE_NOT_SUPPORTED = 0, /* must be 0 */
505 DEVICE_REMOVABLE_UNKNOWN,
506 DEVICE_FIXED,
507 DEVICE_REMOVABLE,
508 };
509
510 /**
511 * struct dev_links_info - Device data related to device links.
512 * @suppliers: List of links to supplier devices.
513 * @consumers: List of links to consumer devices.
514 * @defer_sync: Hook to global list of devices that have deferred sync_state.
515 * @status: Driver status information.
516 */
517 struct dev_links_info {
518 struct list_head suppliers;
519 struct list_head consumers;
520 struct list_head defer_sync;
521 enum dl_dev_state status;
522 };
523
524 /**
525 * struct dev_msi_info - Device data related to MSI
526 * @domain: The MSI interrupt domain associated to the device
527 * @data: Pointer to MSI device data
528 */
529 struct dev_msi_info {
530 #ifdef CONFIG_GENERIC_MSI_IRQ
531 struct irq_domain *domain;
532 struct msi_device_data *data;
533 #endif
534 };
535
536 /**
537 * enum device_physical_location_panel - Describes which panel surface of the
538 * system's housing the device connection point resides on.
539 * @DEVICE_PANEL_TOP: Device connection point is on the top panel.
540 * @DEVICE_PANEL_BOTTOM: Device connection point is on the bottom panel.
541 * @DEVICE_PANEL_LEFT: Device connection point is on the left panel.
542 * @DEVICE_PANEL_RIGHT: Device connection point is on the right panel.
543 * @DEVICE_PANEL_FRONT: Device connection point is on the front panel.
544 * @DEVICE_PANEL_BACK: Device connection point is on the back panel.
545 * @DEVICE_PANEL_UNKNOWN: The panel with device connection point is unknown.
546 */
547 enum device_physical_location_panel {
548 DEVICE_PANEL_TOP,
549 DEVICE_PANEL_BOTTOM,
550 DEVICE_PANEL_LEFT,
551 DEVICE_PANEL_RIGHT,
552 DEVICE_PANEL_FRONT,
553 DEVICE_PANEL_BACK,
554 DEVICE_PANEL_UNKNOWN,
555 };
556
557 /**
558 * enum device_physical_location_vertical_position - Describes vertical
559 * position of the device connection point on the panel surface.
560 * @DEVICE_VERT_POS_UPPER: Device connection point is at upper part of panel.
561 * @DEVICE_VERT_POS_CENTER: Device connection point is at center part of panel.
562 * @DEVICE_VERT_POS_LOWER: Device connection point is at lower part of panel.
563 */
564 enum device_physical_location_vertical_position {
565 DEVICE_VERT_POS_UPPER,
566 DEVICE_VERT_POS_CENTER,
567 DEVICE_VERT_POS_LOWER,
568 };
569
570 /**
571 * enum device_physical_location_horizontal_position - Describes horizontal
572 * position of the device connection point on the panel surface.
573 * @DEVICE_HORI_POS_LEFT: Device connection point is at left part of panel.
574 * @DEVICE_HORI_POS_CENTER: Device connection point is at center part of panel.
575 * @DEVICE_HORI_POS_RIGHT: Device connection point is at right part of panel.
576 */
577 enum device_physical_location_horizontal_position {
578 DEVICE_HORI_POS_LEFT,
579 DEVICE_HORI_POS_CENTER,
580 DEVICE_HORI_POS_RIGHT,
581 };
582
583 /**
584 * struct device_physical_location - Device data related to physical location
585 * of the device connection point.
586 * @panel: Panel surface of the system's housing that the device connection
587 * point resides on.
588 * @vertical_position: Vertical position of the device connection point within
589 * the panel.
590 * @horizontal_position: Horizontal position of the device connection point
591 * within the panel.
592 * @dock: Set if the device connection point resides in a docking station or
593 * port replicator.
594 * @lid: Set if this device connection point resides on the lid of laptop
595 * system.
596 */
597 struct device_physical_location {
598 enum device_physical_location_panel panel;
599 enum device_physical_location_vertical_position vertical_position;
600 enum device_physical_location_horizontal_position horizontal_position;
601 bool dock;
602 bool lid;
603 };
604
605 /**
606 * struct device - The basic device structure
607 * @parent: The device's "parent" device, the device to which it is attached.
608 * In most cases, a parent device is some sort of bus or host
609 * controller. If parent is NULL, the device, is a top-level device,
610 * which is not usually what you want.
611 * @p: Holds the private data of the driver core portions of the device.
612 * See the comment of the struct device_private for detail.
613 * @kobj: A top-level, abstract class from which other classes are derived.
614 * @init_name: Initial name of the device.
615 * @type: The type of device.
616 * This identifies the device type and carries type-specific
617 * information.
618 * @mutex: Mutex to synchronize calls to its driver.
619 * @bus: Type of bus device is on.
620 * @driver: Which driver has allocated this
621 * @platform_data: Platform data specific to the device.
622 * Example: For devices on custom boards, as typical of embedded
623 * and SOC based hardware, Linux often uses platform_data to point
624 * to board-specific structures describing devices and how they
625 * are wired. That can include what ports are available, chip
626 * variants, which GPIO pins act in what additional roles, and so
627 * on. This shrinks the "Board Support Packages" (BSPs) and
628 * minimizes board-specific #ifdefs in drivers.
629 * @driver_data: Private pointer for driver specific info.
630 * @links: Links to suppliers and consumers of this device.
631 * @power: For device power management.
632 * See Documentation/driver-api/pm/devices.rst for details.
633 * @pm_domain: Provide callbacks that are executed during system suspend,
634 * hibernation, system resume and during runtime PM transitions
635 * along with subsystem-level and driver-level callbacks.
636 * @em_pd: device's energy model performance domain
637 * @pins: For device pin management.
638 * See Documentation/driver-api/pin-control.rst for details.
639 * @msi: MSI related data
640 * @numa_node: NUMA node this device is close to.
641 * @dma_ops: DMA mapping operations for this device.
642 * @dma_mask: Dma mask (if dma'ble device).
643 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
644 * hardware supports 64-bit addresses for consistent allocations
645 * such descriptors.
646 * @bus_dma_limit: Limit of an upstream bridge or bus which imposes a smaller
647 * DMA limit than the device itself supports.
648 * @dma_range_map: map for DMA memory ranges relative to that of RAM
649 * @dma_parms: A low level driver may set these to teach IOMMU code about
650 * segment limitations.
651 * @dma_pools: Dma pools (if dma'ble device).
652 * @dma_mem: Internal for coherent mem override.
653 * @cma_area: Contiguous memory area for dma allocations
654 * @dma_io_tlb_mem: Software IO TLB allocator. Not for driver use.
655 * @dma_io_tlb_pools: List of transient swiotlb memory pools.
656 * @dma_io_tlb_lock: Protects changes to the list of active pools.
657 * @dma_uses_io_tlb: %true if device has used the software IO TLB.
658 * @archdata: For arch-specific additions.
659 * @of_node: Associated device tree node.
660 * @fwnode: Associated device node supplied by platform firmware.
661 * @devt: For creating the sysfs "dev".
662 * @id: device instance
663 * @devres_lock: Spinlock to protect the resource of the device.
664 * @devres_head: The resources list of the device.
665 * @knode_class: The node used to add the device to the class list.
666 * @class: The class of the device.
667 * @groups: Optional attribute groups.
668 * @release: Callback to free the device after all references have
669 * gone away. This should be set by the allocator of the
670 * device (i.e. the bus driver that discovered the device).
671 * @iommu_group: IOMMU group the device belongs to.
672 * @iommu: Per device generic IOMMU runtime data
673 * @physical_location: Describes physical location of the device connection
674 * point in the system housing.
675 * @removable: Whether the device can be removed from the system. This
676 * should be set by the subsystem / bus driver that discovered
677 * the device.
678 *
679 * @offline_disabled: If set, the device is permanently online.
680 * @offline: Set after successful invocation of bus type's .offline().
681 * @of_node_reused: Set if the device-tree node is shared with an ancestor
682 * device.
683 * @state_synced: The hardware state of this device has been synced to match
684 * the software state of this device by calling the driver/bus
685 * sync_state() callback.
686 * @can_match: The device has matched with a driver at least once or it is in
687 * a bus (like AMBA) which can't check for matching drivers until
688 * other devices probe successfully.
689 * @dma_coherent: this particular device is dma coherent, even if the
690 * architecture supports non-coherent devices.
691 * @dma_ops_bypass: If set to %true then the dma_ops are bypassed for the
692 * streaming DMA operations (->map_* / ->unmap_* / ->sync_*),
693 * and optionall (if the coherent mask is large enough) also
694 * for dma allocations. This flag is managed by the dma ops
695 * instance from ->dma_supported.
696 *
697 * At the lowest level, every device in a Linux system is represented by an
698 * instance of struct device. The device structure contains the information
699 * that the device model core needs to model the system. Most subsystems,
700 * however, track additional information about the devices they host. As a
701 * result, it is rare for devices to be represented by bare device structures;
702 * instead, that structure, like kobject structures, is usually embedded within
703 * a higher-level representation of the device.
704 */
705 struct device {
706 struct kobject kobj;
707 struct device *parent;
708
709 struct device_private *p;
710
711 const char *init_name; /* initial name of the device */
712 const struct device_type *type;
713
714 const struct bus_type *bus; /* type of bus device is on */
715 struct device_driver *driver; /* which driver has allocated this
716 device */
717 void *platform_data; /* Platform specific data, device
718 core doesn't touch it */
719 void *driver_data; /* Driver data, set and get with
720 dev_set_drvdata/dev_get_drvdata */
721 struct mutex mutex; /* mutex to synchronize calls to
722 * its driver.
723 */
724
725 struct dev_links_info links;
726 struct dev_pm_info power;
727 struct dev_pm_domain *pm_domain;
728
729 #ifdef CONFIG_ENERGY_MODEL
730 struct em_perf_domain *em_pd;
731 #endif
732
733 #ifdef CONFIG_PINCTRL
734 struct dev_pin_info *pins;
735 #endif
736 struct dev_msi_info msi;
737 #ifdef CONFIG_DMA_OPS
738 const struct dma_map_ops *dma_ops;
739 #endif
740 u64 *dma_mask; /* dma mask (if dma'able device) */
741 u64 coherent_dma_mask;/* Like dma_mask, but for
742 alloc_coherent mappings as
743 not all hardware supports
744 64 bit addresses for consistent
745 allocations such descriptors. */
746 u64 bus_dma_limit; /* upstream dma constraint */
747 const struct bus_dma_region *dma_range_map;
748
749 struct device_dma_parameters *dma_parms;
750
751 struct list_head dma_pools; /* dma pools (if dma'ble) */
752
753 #ifdef CONFIG_DMA_DECLARE_COHERENT
754 struct dma_coherent_mem *dma_mem; /* internal for coherent mem
755 override */
756 #endif
757 #ifdef CONFIG_DMA_CMA
758 struct cma *cma_area; /* contiguous memory area for dma
759 allocations */
760 #endif
761 #ifdef CONFIG_SWIOTLB
762 struct io_tlb_mem *dma_io_tlb_mem;
763 #endif
764 #ifdef CONFIG_SWIOTLB_DYNAMIC
765 struct list_head dma_io_tlb_pools;
766 spinlock_t dma_io_tlb_lock;
767 bool dma_uses_io_tlb;
768 #endif
769 /* arch specific additions */
770 struct dev_archdata archdata;
771
772 struct device_node *of_node; /* associated device tree node */
773 struct fwnode_handle *fwnode; /* firmware device node */
774
775 #ifdef CONFIG_NUMA
776 int numa_node; /* NUMA node this device is close to */
777 #endif
778 dev_t devt; /* dev_t, creates the sysfs "dev" */
779 u32 id; /* device instance */
780
781 spinlock_t devres_lock;
782 struct list_head devres_head;
783
784 const struct class *class;
785 const struct attribute_group **groups; /* optional groups */
786
787 void (*release)(struct device *dev);
788 struct iommu_group *iommu_group;
789 struct dev_iommu *iommu;
790
791 struct device_physical_location *physical_location;
792
793 enum device_removable removable;
794
795 bool offline_disabled:1;
796 bool offline:1;
797 bool of_node_reused:1;
798 bool state_synced:1;
799 bool can_match:1;
800 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
801 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
802 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
803 bool dma_coherent:1;
804 #endif
805 #ifdef CONFIG_DMA_OPS_BYPASS
806 bool dma_ops_bypass : 1;
807 #endif
808 };
809
810 /**
811 * struct device_link - Device link representation.
812 * @supplier: The device on the supplier end of the link.
813 * @s_node: Hook to the supplier device's list of links to consumers.
814 * @consumer: The device on the consumer end of the link.
815 * @c_node: Hook to the consumer device's list of links to suppliers.
816 * @link_dev: device used to expose link details in sysfs
817 * @status: The state of the link (with respect to the presence of drivers).
818 * @flags: Link flags.
819 * @rpm_active: Whether or not the consumer device is runtime-PM-active.
820 * @kref: Count repeated addition of the same link.
821 * @rm_work: Work structure used for removing the link.
822 * @supplier_preactivated: Supplier has been made active before consumer probe.
823 */
824 struct device_link {
825 struct device *supplier;
826 struct list_head s_node;
827 struct device *consumer;
828 struct list_head c_node;
829 struct device link_dev;
830 enum device_link_state status;
831 u32 flags;
832 refcount_t rpm_active;
833 struct kref kref;
834 struct work_struct rm_work;
835 bool supplier_preactivated; /* Owned by consumer probe. */
836 };
837
838 #define kobj_to_dev(__kobj) container_of_const(__kobj, struct device, kobj)
839
840 /**
841 * device_iommu_mapped - Returns true when the device DMA is translated
842 * by an IOMMU
843 * @dev: Device to perform the check on
844 */
device_iommu_mapped(struct device * dev)845 static inline bool device_iommu_mapped(struct device *dev)
846 {
847 return (dev->iommu_group != NULL);
848 }
849
850 /* Get the wakeup routines, which depend on struct device */
851 #include <linux/pm_wakeup.h>
852
853 /**
854 * dev_name - Return a device's name.
855 * @dev: Device with name to get.
856 * Return: The kobject name of the device, or its initial name if unavailable.
857 */
dev_name(const struct device * dev)858 static inline const char *dev_name(const struct device *dev)
859 {
860 /* Use the init name until the kobject becomes available */
861 if (dev->init_name)
862 return dev->init_name;
863
864 return kobject_name(&dev->kobj);
865 }
866
867 /**
868 * dev_bus_name - Return a device's bus/class name, if at all possible
869 * @dev: struct device to get the bus/class name of
870 *
871 * Will return the name of the bus/class the device is attached to. If it is
872 * not attached to a bus/class, an empty string will be returned.
873 */
dev_bus_name(const struct device * dev)874 static inline const char *dev_bus_name(const struct device *dev)
875 {
876 return dev->bus ? dev->bus->name : (dev->class ? dev->class->name : "");
877 }
878
879 __printf(2, 3) int dev_set_name(struct device *dev, const char *name, ...);
880
881 #ifdef CONFIG_NUMA
dev_to_node(struct device * dev)882 static inline int dev_to_node(struct device *dev)
883 {
884 return dev->numa_node;
885 }
set_dev_node(struct device * dev,int node)886 static inline void set_dev_node(struct device *dev, int node)
887 {
888 dev->numa_node = node;
889 }
890 #else
dev_to_node(struct device * dev)891 static inline int dev_to_node(struct device *dev)
892 {
893 return NUMA_NO_NODE;
894 }
set_dev_node(struct device * dev,int node)895 static inline void set_dev_node(struct device *dev, int node)
896 {
897 }
898 #endif
899
dev_get_msi_domain(const struct device * dev)900 static inline struct irq_domain *dev_get_msi_domain(const struct device *dev)
901 {
902 #ifdef CONFIG_GENERIC_MSI_IRQ
903 return dev->msi.domain;
904 #else
905 return NULL;
906 #endif
907 }
908
dev_set_msi_domain(struct device * dev,struct irq_domain * d)909 static inline void dev_set_msi_domain(struct device *dev, struct irq_domain *d)
910 {
911 #ifdef CONFIG_GENERIC_MSI_IRQ
912 dev->msi.domain = d;
913 #endif
914 }
915
dev_get_drvdata(const struct device * dev)916 static inline void *dev_get_drvdata(const struct device *dev)
917 {
918 return dev->driver_data;
919 }
920
dev_set_drvdata(struct device * dev,void * data)921 static inline void dev_set_drvdata(struct device *dev, void *data)
922 {
923 dev->driver_data = data;
924 }
925
dev_to_psd(struct device * dev)926 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
927 {
928 return dev ? dev->power.subsys_data : NULL;
929 }
930
dev_get_uevent_suppress(const struct device * dev)931 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
932 {
933 return dev->kobj.uevent_suppress;
934 }
935
dev_set_uevent_suppress(struct device * dev,int val)936 static inline void dev_set_uevent_suppress(struct device *dev, int val)
937 {
938 dev->kobj.uevent_suppress = val;
939 }
940
device_is_registered(struct device * dev)941 static inline int device_is_registered(struct device *dev)
942 {
943 return dev->kobj.state_in_sysfs;
944 }
945
device_enable_async_suspend(struct device * dev)946 static inline void device_enable_async_suspend(struct device *dev)
947 {
948 if (!dev->power.is_prepared)
949 dev->power.async_suspend = true;
950 }
951
device_disable_async_suspend(struct device * dev)952 static inline void device_disable_async_suspend(struct device *dev)
953 {
954 if (!dev->power.is_prepared)
955 dev->power.async_suspend = false;
956 }
957
device_async_suspend_enabled(struct device * dev)958 static inline bool device_async_suspend_enabled(struct device *dev)
959 {
960 return !!dev->power.async_suspend;
961 }
962
device_pm_not_required(struct device * dev)963 static inline bool device_pm_not_required(struct device *dev)
964 {
965 return dev->power.no_pm;
966 }
967
device_set_pm_not_required(struct device * dev)968 static inline void device_set_pm_not_required(struct device *dev)
969 {
970 dev->power.no_pm = true;
971 }
972
dev_pm_syscore_device(struct device * dev,bool val)973 static inline void dev_pm_syscore_device(struct device *dev, bool val)
974 {
975 #ifdef CONFIG_PM_SLEEP
976 dev->power.syscore = val;
977 #endif
978 }
979
dev_pm_set_driver_flags(struct device * dev,u32 flags)980 static inline void dev_pm_set_driver_flags(struct device *dev, u32 flags)
981 {
982 dev->power.driver_flags = flags;
983 }
984
dev_pm_test_driver_flags(struct device * dev,u32 flags)985 static inline bool dev_pm_test_driver_flags(struct device *dev, u32 flags)
986 {
987 return !!(dev->power.driver_flags & flags);
988 }
989
device_lock(struct device * dev)990 static inline void device_lock(struct device *dev)
991 {
992 mutex_lock(&dev->mutex);
993 }
994
device_lock_interruptible(struct device * dev)995 static inline int device_lock_interruptible(struct device *dev)
996 {
997 return mutex_lock_interruptible(&dev->mutex);
998 }
999
device_trylock(struct device * dev)1000 static inline int device_trylock(struct device *dev)
1001 {
1002 return mutex_trylock(&dev->mutex);
1003 }
1004
device_unlock(struct device * dev)1005 static inline void device_unlock(struct device *dev)
1006 {
1007 mutex_unlock(&dev->mutex);
1008 }
1009
DEFINE_GUARD(device,struct device *,device_lock (_T),device_unlock (_T))1010 DEFINE_GUARD(device, struct device *, device_lock(_T), device_unlock(_T))
1011
1012 static inline void device_lock_assert(struct device *dev)
1013 {
1014 lockdep_assert_held(&dev->mutex);
1015 }
1016
dev_of_node(struct device * dev)1017 static inline struct device_node *dev_of_node(struct device *dev)
1018 {
1019 if (!IS_ENABLED(CONFIG_OF) || !dev)
1020 return NULL;
1021 return dev->of_node;
1022 }
1023
dev_has_sync_state(struct device * dev)1024 static inline bool dev_has_sync_state(struct device *dev)
1025 {
1026 if (!dev)
1027 return false;
1028 if (dev->driver && dev->driver->sync_state)
1029 return true;
1030 if (dev->bus && dev->bus->sync_state)
1031 return true;
1032 return false;
1033 }
1034
dev_set_removable(struct device * dev,enum device_removable removable)1035 static inline void dev_set_removable(struct device *dev,
1036 enum device_removable removable)
1037 {
1038 dev->removable = removable;
1039 }
1040
dev_is_removable(struct device * dev)1041 static inline bool dev_is_removable(struct device *dev)
1042 {
1043 return dev->removable == DEVICE_REMOVABLE;
1044 }
1045
dev_removable_is_valid(struct device * dev)1046 static inline bool dev_removable_is_valid(struct device *dev)
1047 {
1048 return dev->removable != DEVICE_REMOVABLE_NOT_SUPPORTED;
1049 }
1050
1051 /*
1052 * High level routines for use by the bus drivers
1053 */
1054 int __must_check device_register(struct device *dev);
1055 void device_unregister(struct device *dev);
1056 void device_initialize(struct device *dev);
1057 int __must_check device_add(struct device *dev);
1058 void device_del(struct device *dev);
1059
1060 DEFINE_FREE(device_del, struct device *, if (_T) device_del(_T))
1061
1062 int device_for_each_child(struct device *dev, void *data,
1063 int (*fn)(struct device *dev, void *data));
1064 int device_for_each_child_reverse(struct device *dev, void *data,
1065 int (*fn)(struct device *dev, void *data));
1066 struct device *device_find_child(struct device *dev, void *data,
1067 int (*match)(struct device *dev, void *data));
1068 struct device *device_find_child_by_name(struct device *parent,
1069 const char *name);
1070 struct device *device_find_any_child(struct device *parent);
1071
1072 int device_rename(struct device *dev, const char *new_name);
1073 int device_move(struct device *dev, struct device *new_parent,
1074 enum dpm_order dpm_order);
1075 int device_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid);
1076 int device_is_dependent(struct device *dev, void *target);
1077
device_supports_offline(struct device * dev)1078 static inline bool device_supports_offline(struct device *dev)
1079 {
1080 return dev->bus && dev->bus->offline && dev->bus->online;
1081 }
1082
1083 #define __device_lock_set_class(dev, name, key) \
1084 do { \
1085 struct device *__d2 __maybe_unused = dev; \
1086 lock_set_class(&__d2->mutex.dep_map, name, key, 0, _THIS_IP_); \
1087 } while (0)
1088
1089 /**
1090 * device_lock_set_class - Specify a temporary lock class while a device
1091 * is attached to a driver
1092 * @dev: device to modify
1093 * @key: lock class key data
1094 *
1095 * This must be called with the device_lock() already held, for example
1096 * from driver ->probe(). Take care to only override the default
1097 * lockdep_no_validate class.
1098 */
1099 #ifdef CONFIG_LOCKDEP
1100 #define device_lock_set_class(dev, key) \
1101 do { \
1102 struct device *__d = dev; \
1103 dev_WARN_ONCE(__d, !lockdep_match_class(&__d->mutex, \
1104 &__lockdep_no_validate__), \
1105 "overriding existing custom lock class\n"); \
1106 __device_lock_set_class(__d, #key, key); \
1107 } while (0)
1108 #else
1109 #define device_lock_set_class(dev, key) __device_lock_set_class(dev, #key, key)
1110 #endif
1111
1112 /**
1113 * device_lock_reset_class - Return a device to the default lockdep novalidate state
1114 * @dev: device to modify
1115 *
1116 * This must be called with the device_lock() already held, for example
1117 * from driver ->remove().
1118 */
1119 #define device_lock_reset_class(dev) \
1120 do { \
1121 struct device *__d __maybe_unused = dev; \
1122 lock_set_novalidate_class(&__d->mutex.dep_map, "&dev->mutex", \
1123 _THIS_IP_); \
1124 } while (0)
1125
1126 void lock_device_hotplug(void);
1127 void unlock_device_hotplug(void);
1128 int lock_device_hotplug_sysfs(void);
1129 int device_offline(struct device *dev);
1130 int device_online(struct device *dev);
1131 void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1132 void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1133 void device_set_of_node_from_dev(struct device *dev, const struct device *dev2);
1134 void device_set_node(struct device *dev, struct fwnode_handle *fwnode);
1135
dev_num_vf(struct device * dev)1136 static inline int dev_num_vf(struct device *dev)
1137 {
1138 if (dev->bus && dev->bus->num_vf)
1139 return dev->bus->num_vf(dev);
1140 return 0;
1141 }
1142
1143 /*
1144 * Root device objects for grouping under /sys/devices
1145 */
1146 struct device *__root_device_register(const char *name, struct module *owner);
1147
1148 /* This is a macro to avoid include problems with THIS_MODULE */
1149 #define root_device_register(name) \
1150 __root_device_register(name, THIS_MODULE)
1151
1152 void root_device_unregister(struct device *root);
1153
dev_get_platdata(const struct device * dev)1154 static inline void *dev_get_platdata(const struct device *dev)
1155 {
1156 return dev->platform_data;
1157 }
1158
1159 /*
1160 * Manual binding of a device to driver. See drivers/base/bus.c
1161 * for information on use.
1162 */
1163 int __must_check device_driver_attach(struct device_driver *drv,
1164 struct device *dev);
1165 int __must_check device_bind_driver(struct device *dev);
1166 void device_release_driver(struct device *dev);
1167 int __must_check device_attach(struct device *dev);
1168 int __must_check driver_attach(struct device_driver *drv);
1169 void device_initial_probe(struct device *dev);
1170 int __must_check device_reprobe(struct device *dev);
1171
1172 bool device_is_bound(struct device *dev);
1173
1174 /*
1175 * Easy functions for dynamically creating devices on the fly
1176 */
1177 __printf(5, 6) struct device *
1178 device_create(const struct class *cls, struct device *parent, dev_t devt,
1179 void *drvdata, const char *fmt, ...);
1180 __printf(6, 7) struct device *
1181 device_create_with_groups(const struct class *cls, struct device *parent, dev_t devt,
1182 void *drvdata, const struct attribute_group **groups,
1183 const char *fmt, ...);
1184 void device_destroy(const struct class *cls, dev_t devt);
1185
1186 int __must_check device_add_groups(struct device *dev,
1187 const struct attribute_group **groups);
1188 void device_remove_groups(struct device *dev,
1189 const struct attribute_group **groups);
1190
device_add_group(struct device * dev,const struct attribute_group * grp)1191 static inline int __must_check device_add_group(struct device *dev,
1192 const struct attribute_group *grp)
1193 {
1194 const struct attribute_group *groups[] = { grp, NULL };
1195
1196 return device_add_groups(dev, groups);
1197 }
1198
device_remove_group(struct device * dev,const struct attribute_group * grp)1199 static inline void device_remove_group(struct device *dev,
1200 const struct attribute_group *grp)
1201 {
1202 const struct attribute_group *groups[] = { grp, NULL };
1203
1204 return device_remove_groups(dev, groups);
1205 }
1206
1207 int __must_check devm_device_add_groups(struct device *dev,
1208 const struct attribute_group **groups);
1209 int __must_check devm_device_add_group(struct device *dev,
1210 const struct attribute_group *grp);
1211
1212 /*
1213 * Platform "fixup" functions - allow the platform to have their say
1214 * about devices and actions that the general device layer doesn't
1215 * know about.
1216 */
1217 /* Notify platform of device discovery */
1218 extern int (*platform_notify)(struct device *dev);
1219
1220 extern int (*platform_notify_remove)(struct device *dev);
1221
1222
1223 /*
1224 * get_device - atomically increment the reference count for the device.
1225 *
1226 */
1227 struct device *get_device(struct device *dev);
1228 void put_device(struct device *dev);
1229
1230 DEFINE_FREE(put_device, struct device *, if (_T) put_device(_T))
1231
1232 bool kill_device(struct device *dev);
1233
1234 #ifdef CONFIG_DEVTMPFS
1235 int devtmpfs_mount(void);
1236 #else
devtmpfs_mount(void)1237 static inline int devtmpfs_mount(void) { return 0; }
1238 #endif
1239
1240 /* drivers/base/power/shutdown.c */
1241 void device_shutdown(void);
1242
1243 /* debugging and troubleshooting/diagnostic helpers. */
1244 const char *dev_driver_string(const struct device *dev);
1245
1246 /* Device links interface. */
1247 struct device_link *device_link_add(struct device *consumer,
1248 struct device *supplier, u32 flags);
1249 void device_link_del(struct device_link *link);
1250 void device_link_remove(void *consumer, struct device *supplier);
1251 void device_links_supplier_sync_state_pause(void);
1252 void device_links_supplier_sync_state_resume(void);
1253 void device_link_wait_removal(void);
1254
1255 /* Create alias, so I can be autoloaded. */
1256 #define MODULE_ALIAS_CHARDEV(major,minor) \
1257 MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1258 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1259 MODULE_ALIAS("char-major-" __stringify(major) "-*")
1260
1261 #endif /* _DEVICE_H_ */
1262