xref: /linux-6.15/include/linux/device.h (revision e9e8bcb8)
1 /*
2  * device.h - generic, centralized driver model
3  *
4  * Copyright (c) 2001-2003 Patrick Mochel <[email protected]>
5  * Copyright (c) 2004-2009 Greg Kroah-Hartman <[email protected]>
6  * Copyright (c) 2008-2009 Novell Inc.
7  *
8  * This file is released under the GPLv2
9  *
10  * See Documentation/driver-model/ for more information.
11  */
12 
13 #ifndef _DEVICE_H_
14 #define _DEVICE_H_
15 
16 #include <linux/ioport.h>
17 #include <linux/kobject.h>
18 #include <linux/klist.h>
19 #include <linux/list.h>
20 #include <linux/lockdep.h>
21 #include <linux/compiler.h>
22 #include <linux/types.h>
23 #include <linux/module.h>
24 #include <linux/pm.h>
25 #include <asm/atomic.h>
26 #include <asm/device.h>
27 
28 struct device;
29 struct device_private;
30 struct device_driver;
31 struct driver_private;
32 struct class;
33 struct subsys_private;
34 struct bus_type;
35 struct device_node;
36 
37 struct bus_attribute {
38 	struct attribute	attr;
39 	ssize_t (*show)(struct bus_type *bus, char *buf);
40 	ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
41 };
42 
43 #define BUS_ATTR(_name, _mode, _show, _store)	\
44 struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)
45 
46 extern int __must_check bus_create_file(struct bus_type *,
47 					struct bus_attribute *);
48 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
49 
50 /**
51  * struct bus_type - The bus type of the device
52  *
53  * @name:	The name of the bus.
54  * @bus_attrs:	Default attributes of the bus.
55  * @dev_attrs:	Default attributes of the devices on the bus.
56  * @drv_attrs:	Default attributes of the device drivers on the bus.
57  * @match:	Called, perhaps multiple times, whenever a new device or driver
58  *		is added for this bus. It should return a nonzero value if the
59  *		given device can be handled by the given driver.
60  * @uevent:	Called when a device is added, removed, or a few other things
61  *		that generate uevents to add the environment variables.
62  * @probe:	Called when a new device or driver add to this bus, and callback
63  *		the specific driver's probe to initial the matched device.
64  * @remove:	Called when a device removed from this bus.
65  * @shutdown:	Called at shut-down time to quiesce the device.
66  * @suspend:	Called when a device on this bus wants to go to sleep mode.
67  * @resume:	Called to bring a device on this bus out of sleep mode.
68  * @pm:		Power management operations of this bus, callback the specific
69  *		device driver's pm-ops.
70  * @p:		The private data of the driver core, only the driver core can
71  *		touch this.
72  *
73  * A bus is a channel between the processor and one or more devices. For the
74  * purposes of the device model, all devices are connected via a bus, even if
75  * it is an internal, virtual, "platform" bus. Buses can plug into each other.
76  * A USB controller is usually a PCI device, for example. The device model
77  * represents the actual connections between buses and the devices they control.
78  * A bus is represented by the bus_type structure. It contains the name, the
79  * default attributes, the bus' methods, PM operations, and the driver core's
80  * private data.
81  */
82 struct bus_type {
83 	const char		*name;
84 	struct bus_attribute	*bus_attrs;
85 	struct device_attribute	*dev_attrs;
86 	struct driver_attribute	*drv_attrs;
87 
88 	int (*match)(struct device *dev, struct device_driver *drv);
89 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
90 	int (*probe)(struct device *dev);
91 	int (*remove)(struct device *dev);
92 	void (*shutdown)(struct device *dev);
93 
94 	int (*suspend)(struct device *dev, pm_message_t state);
95 	int (*resume)(struct device *dev);
96 
97 	const struct dev_pm_ops *pm;
98 
99 	struct subsys_private *p;
100 };
101 
102 extern int __must_check bus_register(struct bus_type *bus);
103 extern void bus_unregister(struct bus_type *bus);
104 
105 extern int __must_check bus_rescan_devices(struct bus_type *bus);
106 
107 /* iterator helpers for buses */
108 
109 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
110 		     int (*fn)(struct device *dev, void *data));
111 struct device *bus_find_device(struct bus_type *bus, struct device *start,
112 			       void *data,
113 			       int (*match)(struct device *dev, void *data));
114 struct device *bus_find_device_by_name(struct bus_type *bus,
115 				       struct device *start,
116 				       const char *name);
117 
118 int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
119 		     void *data, int (*fn)(struct device_driver *, void *));
120 
121 void bus_sort_breadthfirst(struct bus_type *bus,
122 			   int (*compare)(const struct device *a,
123 					  const struct device *b));
124 /*
125  * Bus notifiers: Get notified of addition/removal of devices
126  * and binding/unbinding of drivers to devices.
127  * In the long run, it should be a replacement for the platform
128  * notify hooks.
129  */
130 struct notifier_block;
131 
132 extern int bus_register_notifier(struct bus_type *bus,
133 				 struct notifier_block *nb);
134 extern int bus_unregister_notifier(struct bus_type *bus,
135 				   struct notifier_block *nb);
136 
137 /* All 4 notifers below get called with the target struct device *
138  * as an argument. Note that those functions are likely to be called
139  * with the device lock held in the core, so be careful.
140  */
141 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
142 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device removed */
143 #define BUS_NOTIFY_BIND_DRIVER		0x00000003 /* driver about to be
144 						      bound */
145 #define BUS_NOTIFY_BOUND_DRIVER		0x00000004 /* driver bound to device */
146 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000005 /* driver about to be
147 						      unbound */
148 #define BUS_NOTIFY_UNBOUND_DRIVER	0x00000006 /* driver is unbound
149 						      from the device */
150 
151 extern struct kset *bus_get_kset(struct bus_type *bus);
152 extern struct klist *bus_get_device_klist(struct bus_type *bus);
153 
154 /**
155  * struct device_driver - The basic device driver structure
156  * @name:	Name of the device driver.
157  * @bus:	The bus which the device of this driver belongs to.
158  * @owner:	The module owner.
159  * @mod_name:	Used for built-in modules.
160  * @suppress_bind_attrs: Disables bind/unbind via sysfs.
161  * @of_match_table: The open firmware table.
162  * @probe:	Called to query the existence of a specific device,
163  *		whether this driver can work with it, and bind the driver
164  *		to a specific device.
165  * @remove:	Called when the device is removed from the system to
166  *		unbind a device from this driver.
167  * @shutdown:	Called at shut-down time to quiesce the device.
168  * @suspend:	Called to put the device to sleep mode. Usually to a
169  *		low power state.
170  * @resume:	Called to bring a device from sleep mode.
171  * @groups:	Default attributes that get created by the driver core
172  *		automatically.
173  * @pm:		Power management operations of the device which matched
174  *		this driver.
175  * @p:		Driver core's private data, no one other than the driver
176  *		core can touch this.
177  *
178  * The device driver-model tracks all of the drivers known to the system.
179  * The main reason for this tracking is to enable the driver core to match
180  * up drivers with new devices. Once drivers are known objects within the
181  * system, however, a number of other things become possible. Device drivers
182  * can export information and configuration variables that are independent
183  * of any specific device.
184  */
185 struct device_driver {
186 	const char		*name;
187 	struct bus_type		*bus;
188 
189 	struct module		*owner;
190 	const char		*mod_name;	/* used for built-in modules */
191 
192 	bool suppress_bind_attrs;	/* disables bind/unbind via sysfs */
193 
194 	const struct of_device_id	*of_match_table;
195 
196 	int (*probe) (struct device *dev);
197 	int (*remove) (struct device *dev);
198 	void (*shutdown) (struct device *dev);
199 	int (*suspend) (struct device *dev, pm_message_t state);
200 	int (*resume) (struct device *dev);
201 	const struct attribute_group **groups;
202 
203 	const struct dev_pm_ops *pm;
204 
205 	struct driver_private *p;
206 };
207 
208 
209 extern int __must_check driver_register(struct device_driver *drv);
210 extern void driver_unregister(struct device_driver *drv);
211 
212 extern struct device_driver *get_driver(struct device_driver *drv);
213 extern void put_driver(struct device_driver *drv);
214 extern struct device_driver *driver_find(const char *name,
215 					 struct bus_type *bus);
216 extern int driver_probe_done(void);
217 extern void wait_for_device_probe(void);
218 
219 
220 /* sysfs interface for exporting driver attributes */
221 
222 struct driver_attribute {
223 	struct attribute attr;
224 	ssize_t (*show)(struct device_driver *driver, char *buf);
225 	ssize_t (*store)(struct device_driver *driver, const char *buf,
226 			 size_t count);
227 };
228 
229 #define DRIVER_ATTR(_name, _mode, _show, _store)	\
230 struct driver_attribute driver_attr_##_name =		\
231 	__ATTR(_name, _mode, _show, _store)
232 
233 extern int __must_check driver_create_file(struct device_driver *driver,
234 					const struct driver_attribute *attr);
235 extern void driver_remove_file(struct device_driver *driver,
236 			       const struct driver_attribute *attr);
237 
238 extern int __must_check driver_add_kobj(struct device_driver *drv,
239 					struct kobject *kobj,
240 					const char *fmt, ...);
241 
242 extern int __must_check driver_for_each_device(struct device_driver *drv,
243 					       struct device *start,
244 					       void *data,
245 					       int (*fn)(struct device *dev,
246 							 void *));
247 struct device *driver_find_device(struct device_driver *drv,
248 				  struct device *start, void *data,
249 				  int (*match)(struct device *dev, void *data));
250 
251 /**
252  * struct class - device classes
253  * @name:	Name of the class.
254  * @owner:	The module owner.
255  * @class_attrs: Default attributes of this class.
256  * @dev_attrs:	Default attributes of the devices belong to the class.
257  * @dev_bin_attrs: Default binary attributes of the devices belong to the class.
258  * @dev_kobj:	The kobject that represents this class and links it into the hierarchy.
259  * @dev_uevent:	Called when a device is added, removed from this class, or a
260  *		few other things that generate uevents to add the environment
261  *		variables.
262  * @devnode:	Callback to provide the devtmpfs.
263  * @class_release: Called to release this class.
264  * @dev_release: Called to release the device.
265  * @suspend:	Used to put the device to sleep mode, usually to a low power
266  *		state.
267  * @resume:	Used to bring the device from the sleep mode.
268  * @ns_type:	Callbacks so sysfs can detemine namespaces.
269  * @namespace:	Namespace of the device belongs to this class.
270  * @pm:		The default device power management operations of this class.
271  * @p:		The private data of the driver core, no one other than the
272  *		driver core can touch this.
273  *
274  * A class is a higher-level view of a device that abstracts out low-level
275  * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
276  * at the class level, they are all simply disks. Classes allow user space
277  * to work with devices based on what they do, rather than how they are
278  * connected or how they work.
279  */
280 struct class {
281 	const char		*name;
282 	struct module		*owner;
283 
284 	struct class_attribute		*class_attrs;
285 	struct device_attribute		*dev_attrs;
286 	struct bin_attribute		*dev_bin_attrs;
287 	struct kobject			*dev_kobj;
288 
289 	int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
290 	char *(*devnode)(struct device *dev, mode_t *mode);
291 
292 	void (*class_release)(struct class *class);
293 	void (*dev_release)(struct device *dev);
294 
295 	int (*suspend)(struct device *dev, pm_message_t state);
296 	int (*resume)(struct device *dev);
297 
298 	const struct kobj_ns_type_operations *ns_type;
299 	const void *(*namespace)(struct device *dev);
300 
301 	const struct dev_pm_ops *pm;
302 
303 	struct subsys_private *p;
304 };
305 
306 struct class_dev_iter {
307 	struct klist_iter		ki;
308 	const struct device_type	*type;
309 };
310 
311 extern struct kobject *sysfs_dev_block_kobj;
312 extern struct kobject *sysfs_dev_char_kobj;
313 extern int __must_check __class_register(struct class *class,
314 					 struct lock_class_key *key);
315 extern void class_unregister(struct class *class);
316 
317 /* This is a #define to keep the compiler from merging different
318  * instances of the __key variable */
319 #define class_register(class)			\
320 ({						\
321 	static struct lock_class_key __key;	\
322 	__class_register(class, &__key);	\
323 })
324 
325 struct class_compat;
326 struct class_compat *class_compat_register(const char *name);
327 void class_compat_unregister(struct class_compat *cls);
328 int class_compat_create_link(struct class_compat *cls, struct device *dev,
329 			     struct device *device_link);
330 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
331 			      struct device *device_link);
332 
333 extern void class_dev_iter_init(struct class_dev_iter *iter,
334 				struct class *class,
335 				struct device *start,
336 				const struct device_type *type);
337 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
338 extern void class_dev_iter_exit(struct class_dev_iter *iter);
339 
340 extern int class_for_each_device(struct class *class, struct device *start,
341 				 void *data,
342 				 int (*fn)(struct device *dev, void *data));
343 extern struct device *class_find_device(struct class *class,
344 					struct device *start, void *data,
345 					int (*match)(struct device *, void *));
346 
347 struct class_attribute {
348 	struct attribute attr;
349 	ssize_t (*show)(struct class *class, struct class_attribute *attr,
350 			char *buf);
351 	ssize_t (*store)(struct class *class, struct class_attribute *attr,
352 			const char *buf, size_t count);
353 };
354 
355 #define CLASS_ATTR(_name, _mode, _show, _store)			\
356 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
357 
358 extern int __must_check class_create_file(struct class *class,
359 					  const struct class_attribute *attr);
360 extern void class_remove_file(struct class *class,
361 			      const struct class_attribute *attr);
362 
363 /* Simple class attribute that is just a static string */
364 
365 struct class_attribute_string {
366 	struct class_attribute attr;
367 	char *str;
368 };
369 
370 /* Currently read-only only */
371 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
372 	{ __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
373 #define CLASS_ATTR_STRING(_name, _mode, _str) \
374 	struct class_attribute_string class_attr_##_name = \
375 		_CLASS_ATTR_STRING(_name, _mode, _str)
376 
377 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
378                         char *buf);
379 
380 struct class_interface {
381 	struct list_head	node;
382 	struct class		*class;
383 
384 	int (*add_dev)		(struct device *, struct class_interface *);
385 	void (*remove_dev)	(struct device *, struct class_interface *);
386 };
387 
388 extern int __must_check class_interface_register(struct class_interface *);
389 extern void class_interface_unregister(struct class_interface *);
390 
391 extern struct class * __must_check __class_create(struct module *owner,
392 						  const char *name,
393 						  struct lock_class_key *key);
394 extern void class_destroy(struct class *cls);
395 
396 /* This is a #define to keep the compiler from merging different
397  * instances of the __key variable */
398 #define class_create(owner, name)		\
399 ({						\
400 	static struct lock_class_key __key;	\
401 	__class_create(owner, name, &__key);	\
402 })
403 
404 /*
405  * The type of device, "struct device" is embedded in. A class
406  * or bus can contain devices of different types
407  * like "partitions" and "disks", "mouse" and "event".
408  * This identifies the device type and carries type-specific
409  * information, equivalent to the kobj_type of a kobject.
410  * If "name" is specified, the uevent will contain it in
411  * the DEVTYPE variable.
412  */
413 struct device_type {
414 	const char *name;
415 	const struct attribute_group **groups;
416 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
417 	char *(*devnode)(struct device *dev, mode_t *mode);
418 	void (*release)(struct device *dev);
419 
420 	const struct dev_pm_ops *pm;
421 };
422 
423 /* interface for exporting device attributes */
424 struct device_attribute {
425 	struct attribute	attr;
426 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
427 			char *buf);
428 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
429 			 const char *buf, size_t count);
430 };
431 
432 #define DEVICE_ATTR(_name, _mode, _show, _store) \
433 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
434 
435 extern int __must_check device_create_file(struct device *device,
436 					const struct device_attribute *entry);
437 extern void device_remove_file(struct device *dev,
438 			       const struct device_attribute *attr);
439 extern int __must_check device_create_bin_file(struct device *dev,
440 					const struct bin_attribute *attr);
441 extern void device_remove_bin_file(struct device *dev,
442 				   const struct bin_attribute *attr);
443 extern int device_schedule_callback_owner(struct device *dev,
444 		void (*func)(struct device *dev), struct module *owner);
445 
446 /* This is a macro to avoid include problems with THIS_MODULE */
447 #define device_schedule_callback(dev, func)			\
448 	device_schedule_callback_owner(dev, func, THIS_MODULE)
449 
450 /* device resource management */
451 typedef void (*dr_release_t)(struct device *dev, void *res);
452 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
453 
454 #ifdef CONFIG_DEBUG_DEVRES
455 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
456 			     const char *name);
457 #define devres_alloc(release, size, gfp) \
458 	__devres_alloc(release, size, gfp, #release)
459 #else
460 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
461 #endif
462 extern void devres_free(void *res);
463 extern void devres_add(struct device *dev, void *res);
464 extern void *devres_find(struct device *dev, dr_release_t release,
465 			 dr_match_t match, void *match_data);
466 extern void *devres_get(struct device *dev, void *new_res,
467 			dr_match_t match, void *match_data);
468 extern void *devres_remove(struct device *dev, dr_release_t release,
469 			   dr_match_t match, void *match_data);
470 extern int devres_destroy(struct device *dev, dr_release_t release,
471 			  dr_match_t match, void *match_data);
472 
473 /* devres group */
474 extern void * __must_check devres_open_group(struct device *dev, void *id,
475 					     gfp_t gfp);
476 extern void devres_close_group(struct device *dev, void *id);
477 extern void devres_remove_group(struct device *dev, void *id);
478 extern int devres_release_group(struct device *dev, void *id);
479 
480 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
481 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
482 extern void devm_kfree(struct device *dev, void *p);
483 
484 struct device_dma_parameters {
485 	/*
486 	 * a low level driver may set these to teach IOMMU code about
487 	 * sg limitations.
488 	 */
489 	unsigned int max_segment_size;
490 	unsigned long segment_boundary_mask;
491 };
492 
493 /**
494  * struct device - The basic device structure
495  * @parent:	The device's "parent" device, the device to which it is attached.
496  * 		In most cases, a parent device is some sort of bus or host
497  * 		controller. If parent is NULL, the device, is a top-level device,
498  * 		which is not usually what you want.
499  * @p:		Holds the private data of the driver core portions of the device.
500  * 		See the comment of the struct device_private for detail.
501  * @kobj:	A top-level, abstract class from which other classes are derived.
502  * @init_name:	Initial name of the device.
503  * @type:	The type of device.
504  * 		This identifies the device type and carries type-specific
505  * 		information.
506  * @mutex:	Mutex to synchronize calls to its driver.
507  * @bus:	Type of bus device is on.
508  * @driver:	Which driver has allocated this
509  * @platform_data: Platform data specific to the device.
510  * 		Example: For devices on custom boards, as typical of embedded
511  * 		and SOC based hardware, Linux often uses platform_data to point
512  * 		to board-specific structures describing devices and how they
513  * 		are wired.  That can include what ports are available, chip
514  * 		variants, which GPIO pins act in what additional roles, and so
515  * 		on.  This shrinks the "Board Support Packages" (BSPs) and
516  * 		minimizes board-specific #ifdefs in drivers.
517  * @power:	For device power management.
518  * 		See Documentation/power/devices.txt for details.
519  * @pwr_domain:	Provide callbacks that are executed during system suspend,
520  * 		hibernation, system resume and during runtime PM transitions
521  * 		along with subsystem-level and driver-level callbacks.
522  * @numa_node:	NUMA node this device is close to.
523  * @dma_mask:	Dma mask (if dma'ble device).
524  * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
525  * 		hardware supports 64-bit addresses for consistent allocations
526  * 		such descriptors.
527  * @dma_parms:	A low level driver may set these to teach IOMMU code about
528  * 		segment limitations.
529  * @dma_pools:	Dma pools (if dma'ble device).
530  * @dma_mem:	Internal for coherent mem override.
531  * @archdata:	For arch-specific additions.
532  * @of_node:	Associated device tree node.
533  * @of_match:	Matching of_device_id from driver.
534  * @devt:	For creating the sysfs "dev".
535  * @devres_lock: Spinlock to protect the resource of the device.
536  * @devres_head: The resources list of the device.
537  * @knode_class: The node used to add the device to the class list.
538  * @class:	The class of the device.
539  * @groups:	Optional attribute groups.
540  * @release:	Callback to free the device after all references have
541  * 		gone away. This should be set by the allocator of the
542  * 		device (i.e. the bus driver that discovered the device).
543  *
544  * At the lowest level, every device in a Linux system is represented by an
545  * instance of struct device. The device structure contains the information
546  * that the device model core needs to model the system. Most subsystems,
547  * however, track additional information about the devices they host. As a
548  * result, it is rare for devices to be represented by bare device structures;
549  * instead, that structure, like kobject structures, is usually embedded within
550  * a higher-level representation of the device.
551  */
552 struct device {
553 	struct device		*parent;
554 
555 	struct device_private	*p;
556 
557 	struct kobject kobj;
558 	const char		*init_name; /* initial name of the device */
559 	const struct device_type *type;
560 
561 	struct mutex		mutex;	/* mutex to synchronize calls to
562 					 * its driver.
563 					 */
564 
565 	struct bus_type	*bus;		/* type of bus device is on */
566 	struct device_driver *driver;	/* which driver has allocated this
567 					   device */
568 	void		*platform_data;	/* Platform specific data, device
569 					   core doesn't touch it */
570 	struct dev_pm_info	power;
571 	struct dev_power_domain	*pwr_domain;
572 
573 #ifdef CONFIG_NUMA
574 	int		numa_node;	/* NUMA node this device is close to */
575 #endif
576 	u64		*dma_mask;	/* dma mask (if dma'able device) */
577 	u64		coherent_dma_mask;/* Like dma_mask, but for
578 					     alloc_coherent mappings as
579 					     not all hardware supports
580 					     64 bit addresses for consistent
581 					     allocations such descriptors. */
582 
583 	struct device_dma_parameters *dma_parms;
584 
585 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
586 
587 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
588 					     override */
589 	/* arch specific additions */
590 	struct dev_archdata	archdata;
591 
592 	struct device_node	*of_node; /* associated device tree node */
593 
594 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
595 
596 	spinlock_t		devres_lock;
597 	struct list_head	devres_head;
598 
599 	struct klist_node	knode_class;
600 	struct class		*class;
601 	const struct attribute_group **groups;	/* optional groups */
602 
603 	void	(*release)(struct device *dev);
604 };
605 
606 /* Get the wakeup routines, which depend on struct device */
607 #include <linux/pm_wakeup.h>
608 
609 static inline const char *dev_name(const struct device *dev)
610 {
611 	/* Use the init name until the kobject becomes available */
612 	if (dev->init_name)
613 		return dev->init_name;
614 
615 	return kobject_name(&dev->kobj);
616 }
617 
618 extern int dev_set_name(struct device *dev, const char *name, ...)
619 			__attribute__((format(printf, 2, 3)));
620 
621 #ifdef CONFIG_NUMA
622 static inline int dev_to_node(struct device *dev)
623 {
624 	return dev->numa_node;
625 }
626 static inline void set_dev_node(struct device *dev, int node)
627 {
628 	dev->numa_node = node;
629 }
630 #else
631 static inline int dev_to_node(struct device *dev)
632 {
633 	return -1;
634 }
635 static inline void set_dev_node(struct device *dev, int node)
636 {
637 }
638 #endif
639 
640 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
641 {
642 	return dev->kobj.uevent_suppress;
643 }
644 
645 static inline void dev_set_uevent_suppress(struct device *dev, int val)
646 {
647 	dev->kobj.uevent_suppress = val;
648 }
649 
650 static inline int device_is_registered(struct device *dev)
651 {
652 	return dev->kobj.state_in_sysfs;
653 }
654 
655 static inline void device_enable_async_suspend(struct device *dev)
656 {
657 	if (!dev->power.in_suspend)
658 		dev->power.async_suspend = true;
659 }
660 
661 static inline void device_disable_async_suspend(struct device *dev)
662 {
663 	if (!dev->power.in_suspend)
664 		dev->power.async_suspend = false;
665 }
666 
667 static inline bool device_async_suspend_enabled(struct device *dev)
668 {
669 	return !!dev->power.async_suspend;
670 }
671 
672 static inline void device_lock(struct device *dev)
673 {
674 	mutex_lock(&dev->mutex);
675 }
676 
677 static inline int device_trylock(struct device *dev)
678 {
679 	return mutex_trylock(&dev->mutex);
680 }
681 
682 static inline void device_unlock(struct device *dev)
683 {
684 	mutex_unlock(&dev->mutex);
685 }
686 
687 void driver_init(void);
688 
689 /*
690  * High level routines for use by the bus drivers
691  */
692 extern int __must_check device_register(struct device *dev);
693 extern void device_unregister(struct device *dev);
694 extern void device_initialize(struct device *dev);
695 extern int __must_check device_add(struct device *dev);
696 extern void device_del(struct device *dev);
697 extern int device_for_each_child(struct device *dev, void *data,
698 		     int (*fn)(struct device *dev, void *data));
699 extern struct device *device_find_child(struct device *dev, void *data,
700 				int (*match)(struct device *dev, void *data));
701 extern int device_rename(struct device *dev, const char *new_name);
702 extern int device_move(struct device *dev, struct device *new_parent,
703 		       enum dpm_order dpm_order);
704 extern const char *device_get_devnode(struct device *dev,
705 				      mode_t *mode, const char **tmp);
706 extern void *dev_get_drvdata(const struct device *dev);
707 extern int dev_set_drvdata(struct device *dev, void *data);
708 
709 /*
710  * Root device objects for grouping under /sys/devices
711  */
712 extern struct device *__root_device_register(const char *name,
713 					     struct module *owner);
714 static inline struct device *root_device_register(const char *name)
715 {
716 	return __root_device_register(name, THIS_MODULE);
717 }
718 extern void root_device_unregister(struct device *root);
719 
720 static inline void *dev_get_platdata(const struct device *dev)
721 {
722 	return dev->platform_data;
723 }
724 
725 /*
726  * Manual binding of a device to driver. See drivers/base/bus.c
727  * for information on use.
728  */
729 extern int __must_check device_bind_driver(struct device *dev);
730 extern void device_release_driver(struct device *dev);
731 extern int  __must_check device_attach(struct device *dev);
732 extern int __must_check driver_attach(struct device_driver *drv);
733 extern int __must_check device_reprobe(struct device *dev);
734 
735 /*
736  * Easy functions for dynamically creating devices on the fly
737  */
738 extern struct device *device_create_vargs(struct class *cls,
739 					  struct device *parent,
740 					  dev_t devt,
741 					  void *drvdata,
742 					  const char *fmt,
743 					  va_list vargs);
744 extern struct device *device_create(struct class *cls, struct device *parent,
745 				    dev_t devt, void *drvdata,
746 				    const char *fmt, ...)
747 				    __attribute__((format(printf, 5, 6)));
748 extern void device_destroy(struct class *cls, dev_t devt);
749 
750 /*
751  * Platform "fixup" functions - allow the platform to have their say
752  * about devices and actions that the general device layer doesn't
753  * know about.
754  */
755 /* Notify platform of device discovery */
756 extern int (*platform_notify)(struct device *dev);
757 
758 extern int (*platform_notify_remove)(struct device *dev);
759 
760 
761 /*
762  * get_device - atomically increment the reference count for the device.
763  *
764  */
765 extern struct device *get_device(struct device *dev);
766 extern void put_device(struct device *dev);
767 
768 extern void wait_for_device_probe(void);
769 
770 #ifdef CONFIG_DEVTMPFS
771 extern int devtmpfs_create_node(struct device *dev);
772 extern int devtmpfs_delete_node(struct device *dev);
773 extern int devtmpfs_mount(const char *mntdir);
774 #else
775 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
776 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
777 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
778 #endif
779 
780 /* drivers/base/power/shutdown.c */
781 extern void device_shutdown(void);
782 
783 /* debugging and troubleshooting/diagnostic helpers. */
784 extern const char *dev_driver_string(const struct device *dev);
785 
786 
787 #ifdef CONFIG_PRINTK
788 
789 extern int dev_printk(const char *level, const struct device *dev,
790 		      const char *fmt, ...)
791 	__attribute__ ((format (printf, 3, 4)));
792 extern int dev_emerg(const struct device *dev, const char *fmt, ...)
793 	__attribute__ ((format (printf, 2, 3)));
794 extern int dev_alert(const struct device *dev, const char *fmt, ...)
795 	__attribute__ ((format (printf, 2, 3)));
796 extern int dev_crit(const struct device *dev, const char *fmt, ...)
797 	__attribute__ ((format (printf, 2, 3)));
798 extern int dev_err(const struct device *dev, const char *fmt, ...)
799 	__attribute__ ((format (printf, 2, 3)));
800 extern int dev_warn(const struct device *dev, const char *fmt, ...)
801 	__attribute__ ((format (printf, 2, 3)));
802 extern int dev_notice(const struct device *dev, const char *fmt, ...)
803 	__attribute__ ((format (printf, 2, 3)));
804 extern int _dev_info(const struct device *dev, const char *fmt, ...)
805 	__attribute__ ((format (printf, 2, 3)));
806 
807 #else
808 
809 static inline int dev_printk(const char *level, const struct device *dev,
810 		      const char *fmt, ...)
811 	__attribute__ ((format (printf, 3, 4)));
812 static inline int dev_printk(const char *level, const struct device *dev,
813 		      const char *fmt, ...)
814 	 { return 0; }
815 
816 static inline int dev_emerg(const struct device *dev, const char *fmt, ...)
817 	__attribute__ ((format (printf, 2, 3)));
818 static inline int dev_emerg(const struct device *dev, const char *fmt, ...)
819 	{ return 0; }
820 static inline int dev_crit(const struct device *dev, const char *fmt, ...)
821 	__attribute__ ((format (printf, 2, 3)));
822 static inline int dev_crit(const struct device *dev, const char *fmt, ...)
823 	{ return 0; }
824 static inline int dev_alert(const struct device *dev, const char *fmt, ...)
825 	__attribute__ ((format (printf, 2, 3)));
826 static inline int dev_alert(const struct device *dev, const char *fmt, ...)
827 	{ return 0; }
828 static inline int dev_err(const struct device *dev, const char *fmt, ...)
829 	__attribute__ ((format (printf, 2, 3)));
830 static inline int dev_err(const struct device *dev, const char *fmt, ...)
831 	{ return 0; }
832 static inline int dev_warn(const struct device *dev, const char *fmt, ...)
833 	__attribute__ ((format (printf, 2, 3)));
834 static inline int dev_warn(const struct device *dev, const char *fmt, ...)
835 	{ return 0; }
836 static inline int dev_notice(const struct device *dev, const char *fmt, ...)
837 	__attribute__ ((format (printf, 2, 3)));
838 static inline int dev_notice(const struct device *dev, const char *fmt, ...)
839 	{ return 0; }
840 static inline int _dev_info(const struct device *dev, const char *fmt, ...)
841 	__attribute__ ((format (printf, 2, 3)));
842 static inline int _dev_info(const struct device *dev, const char *fmt, ...)
843 	{ return 0; }
844 
845 #endif
846 
847 /*
848  * Stupid hackaround for existing uses of non-printk uses dev_info
849  *
850  * Note that the definition of dev_info below is actually _dev_info
851  * and a macro is used to avoid redefining dev_info
852  */
853 
854 #define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)
855 
856 #if defined(DEBUG)
857 #define dev_dbg(dev, format, arg...)		\
858 	dev_printk(KERN_DEBUG, dev, format, ##arg)
859 #elif defined(CONFIG_DYNAMIC_DEBUG)
860 #define dev_dbg(dev, format, ...)		     \
861 do {						     \
862 	dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
863 } while (0)
864 #else
865 #define dev_dbg(dev, format, arg...)				\
866 ({								\
867 	if (0)							\
868 		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
869 	0;							\
870 })
871 #endif
872 
873 #ifdef VERBOSE_DEBUG
874 #define dev_vdbg	dev_dbg
875 #else
876 #define dev_vdbg(dev, format, arg...)				\
877 ({								\
878 	if (0)							\
879 		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
880 	0;							\
881 })
882 #endif
883 
884 /*
885  * dev_WARN*() acts like dev_printk(), but with the key difference
886  * of using a WARN/WARN_ON to get the message out, including the
887  * file/line information and a backtrace.
888  */
889 #define dev_WARN(dev, format, arg...) \
890 	WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg);
891 
892 #define dev_WARN_ONCE(dev, condition, format, arg...) \
893 	WARN_ONCE(condition, "Device %s\n" format, \
894 			dev_driver_string(dev), ## arg)
895 
896 /* Create alias, so I can be autoloaded. */
897 #define MODULE_ALIAS_CHARDEV(major,minor) \
898 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
899 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
900 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
901 
902 #ifdef CONFIG_SYSFS_DEPRECATED
903 extern long sysfs_deprecated;
904 #else
905 #define sysfs_deprecated 0
906 #endif
907 
908 #endif /* _DEVICE_H_ */
909