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 
1254 /* Create alias, so I can be autoloaded. */
1255 #define MODULE_ALIAS_CHARDEV(major,minor) \
1256 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1257 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1258 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
1259 
1260 #endif /* _DEVICE_H_ */
1261