1/*
2 * device.h - generic, centralized driver model
3 *
4 * Copyright (c) 2001-2003 Patrick Mochel <mochel@osdl.org>
5 * Copyright (c) 2004-2009 Greg Kroah-Hartman <gregkh@suse.de>
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/mutex.h>
24#include <linux/pinctrl/devinfo.h>
25#include <linux/pm.h>
26#include <linux/atomic.h>
27#include <linux/ratelimit.h>
28#include <linux/uidgid.h>
29#include <linux/gfp.h>
30#include <asm/device.h>
31
32struct device;
33struct device_private;
34struct device_driver;
35struct driver_private;
36struct module;
37struct class;
38struct subsys_private;
39struct bus_type;
40struct device_node;
41struct fwnode_handle;
42struct iommu_ops;
43struct iommu_group;
44
45struct bus_attribute {
46	struct attribute	attr;
47	ssize_t (*show)(struct bus_type *bus, char *buf);
48	ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
49};
50
51#define BUS_ATTR(_name, _mode, _show, _store)	\
52	struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)
53#define BUS_ATTR_RW(_name) \
54	struct bus_attribute bus_attr_##_name = __ATTR_RW(_name)
55#define BUS_ATTR_RO(_name) \
56	struct bus_attribute bus_attr_##_name = __ATTR_RO(_name)
57
58extern int __must_check bus_create_file(struct bus_type *,
59					struct bus_attribute *);
60extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
61
62/**
63 * struct bus_type - The bus type of the device
64 *
65 * @name:	The name of the bus.
66 * @dev_name:	Used for subsystems to enumerate devices like ("foo%u", dev->id).
67 * @dev_root:	Default device to use as the parent.
68 * @dev_attrs:	Default attributes of the devices on the bus.
69 * @bus_groups:	Default attributes of the bus.
70 * @dev_groups:	Default attributes of the devices on the bus.
71 * @drv_groups: Default attributes of the device drivers on the bus.
72 * @match:	Called, perhaps multiple times, whenever a new device or driver
73 *		is added for this bus. It should return a nonzero value if the
74 *		given device can be handled by the given driver.
75 * @uevent:	Called when a device is added, removed, or a few other things
76 *		that generate uevents to add the environment variables.
77 * @probe:	Called when a new device or driver add to this bus, and callback
78 *		the specific driver's probe to initial the matched device.
79 * @remove:	Called when a device removed from this bus.
80 * @shutdown:	Called at shut-down time to quiesce the device.
81 *
82 * @online:	Called to put the device back online (after offlining it).
83 * @offline:	Called to put the device offline for hot-removal. May fail.
84 *
85 * @suspend:	Called when a device on this bus wants to go to sleep mode.
86 * @resume:	Called to bring a device on this bus out of sleep mode.
87 * @pm:		Power management operations of this bus, callback the specific
88 *		device driver's pm-ops.
89 * @iommu_ops:  IOMMU specific operations for this bus, used to attach IOMMU
90 *              driver implementations to a bus and allow the driver to do
91 *              bus-specific setup
92 * @p:		The private data of the driver core, only the driver core can
93 *		touch this.
94 * @lock_key:	Lock class key for use by the lock validator
95 *
96 * A bus is a channel between the processor and one or more devices. For the
97 * purposes of the device model, all devices are connected via a bus, even if
98 * it is an internal, virtual, "platform" bus. Buses can plug into each other.
99 * A USB controller is usually a PCI device, for example. The device model
100 * represents the actual connections between buses and the devices they control.
101 * A bus is represented by the bus_type structure. It contains the name, the
102 * default attributes, the bus' methods, PM operations, and the driver core's
103 * private data.
104 */
105struct bus_type {
106	const char		*name;
107	const char		*dev_name;
108	struct device		*dev_root;
109	struct device_attribute	*dev_attrs;	/* use dev_groups instead */
110	const struct attribute_group **bus_groups;
111	const struct attribute_group **dev_groups;
112	const struct attribute_group **drv_groups;
113
114	int (*match)(struct device *dev, struct device_driver *drv);
115	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
116	int (*probe)(struct device *dev);
117	int (*remove)(struct device *dev);
118	void (*shutdown)(struct device *dev);
119
120	int (*online)(struct device *dev);
121	int (*offline)(struct device *dev);
122
123	int (*suspend)(struct device *dev, pm_message_t state);
124	int (*resume)(struct device *dev);
125
126	const struct dev_pm_ops *pm;
127
128	const struct iommu_ops *iommu_ops;
129
130	struct subsys_private *p;
131	struct lock_class_key lock_key;
132};
133
134extern int __must_check bus_register(struct bus_type *bus);
135
136extern void bus_unregister(struct bus_type *bus);
137
138extern int __must_check bus_rescan_devices(struct bus_type *bus);
139
140/* iterator helpers for buses */
141struct subsys_dev_iter {
142	struct klist_iter		ki;
143	const struct device_type	*type;
144};
145void subsys_dev_iter_init(struct subsys_dev_iter *iter,
146			 struct bus_type *subsys,
147			 struct device *start,
148			 const struct device_type *type);
149struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter);
150void subsys_dev_iter_exit(struct subsys_dev_iter *iter);
151
152int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
153		     int (*fn)(struct device *dev, void *data));
154struct device *bus_find_device(struct bus_type *bus, struct device *start,
155			       void *data,
156			       int (*match)(struct device *dev, void *data));
157struct device *bus_find_device_by_name(struct bus_type *bus,
158				       struct device *start,
159				       const char *name);
160struct device *subsys_find_device_by_id(struct bus_type *bus, unsigned int id,
161					struct device *hint);
162int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
163		     void *data, int (*fn)(struct device_driver *, void *));
164void bus_sort_breadthfirst(struct bus_type *bus,
165			   int (*compare)(const struct device *a,
166					  const struct device *b));
167/*
168 * Bus notifiers: Get notified of addition/removal of devices
169 * and binding/unbinding of drivers to devices.
170 * In the long run, it should be a replacement for the platform
171 * notify hooks.
172 */
173struct notifier_block;
174
175extern int bus_register_notifier(struct bus_type *bus,
176				 struct notifier_block *nb);
177extern int bus_unregister_notifier(struct bus_type *bus,
178				   struct notifier_block *nb);
179
180/* All 4 notifers below get called with the target struct device *
181 * as an argument. Note that those functions are likely to be called
182 * with the device lock held in the core, so be careful.
183 */
184#define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
185#define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device to be removed */
186#define BUS_NOTIFY_REMOVED_DEVICE	0x00000003 /* device removed */
187#define BUS_NOTIFY_BIND_DRIVER		0x00000004 /* driver about to be
188						      bound */
189#define BUS_NOTIFY_BOUND_DRIVER		0x00000005 /* driver bound to device */
190#define BUS_NOTIFY_UNBIND_DRIVER	0x00000006 /* driver about to be
191						      unbound */
192#define BUS_NOTIFY_UNBOUND_DRIVER	0x00000007 /* driver is unbound
193						      from the device */
194
195extern struct kset *bus_get_kset(struct bus_type *bus);
196extern struct klist *bus_get_device_klist(struct bus_type *bus);
197
198/**
199 * struct device_driver - The basic device driver structure
200 * @name:	Name of the device driver.
201 * @bus:	The bus which the device of this driver belongs to.
202 * @owner:	The module owner.
203 * @mod_name:	Used for built-in modules.
204 * @suppress_bind_attrs: Disables bind/unbind via sysfs.
205 * @of_match_table: The open firmware table.
206 * @acpi_match_table: The ACPI match table.
207 * @probe:	Called to query the existence of a specific device,
208 *		whether this driver can work with it, and bind the driver
209 *		to a specific device.
210 * @remove:	Called when the device is removed from the system to
211 *		unbind a device from this driver.
212 * @shutdown:	Called at shut-down time to quiesce the device.
213 * @suspend:	Called to put the device to sleep mode. Usually to a
214 *		low power state.
215 * @resume:	Called to bring a device from sleep mode.
216 * @groups:	Default attributes that get created by the driver core
217 *		automatically.
218 * @pm:		Power management operations of the device which matched
219 *		this driver.
220 * @p:		Driver core's private data, no one other than the driver
221 *		core can touch this.
222 *
223 * The device driver-model tracks all of the drivers known to the system.
224 * The main reason for this tracking is to enable the driver core to match
225 * up drivers with new devices. Once drivers are known objects within the
226 * system, however, a number of other things become possible. Device drivers
227 * can export information and configuration variables that are independent
228 * of any specific device.
229 */
230struct device_driver {
231	const char		*name;
232	struct bus_type		*bus;
233
234	struct module		*owner;
235	const char		*mod_name;	/* used for built-in modules */
236
237	bool suppress_bind_attrs;	/* disables bind/unbind via sysfs */
238
239	const struct of_device_id	*of_match_table;
240	const struct acpi_device_id	*acpi_match_table;
241
242	int (*probe) (struct device *dev);
243	int (*remove) (struct device *dev);
244	void (*shutdown) (struct device *dev);
245	int (*suspend) (struct device *dev, pm_message_t state);
246	int (*resume) (struct device *dev);
247	const struct attribute_group **groups;
248
249	const struct dev_pm_ops *pm;
250
251	struct driver_private *p;
252};
253
254
255extern int __must_check driver_register(struct device_driver *drv);
256extern void driver_unregister(struct device_driver *drv);
257
258extern struct device_driver *driver_find(const char *name,
259					 struct bus_type *bus);
260extern int driver_probe_done(void);
261extern void wait_for_device_probe(void);
262
263
264/* sysfs interface for exporting driver attributes */
265
266struct driver_attribute {
267	struct attribute attr;
268	ssize_t (*show)(struct device_driver *driver, char *buf);
269	ssize_t (*store)(struct device_driver *driver, const char *buf,
270			 size_t count);
271};
272
273#define DRIVER_ATTR(_name, _mode, _show, _store) \
274	struct driver_attribute driver_attr_##_name = __ATTR(_name, _mode, _show, _store)
275#define DRIVER_ATTR_RW(_name) \
276	struct driver_attribute driver_attr_##_name = __ATTR_RW(_name)
277#define DRIVER_ATTR_RO(_name) \
278	struct driver_attribute driver_attr_##_name = __ATTR_RO(_name)
279#define DRIVER_ATTR_WO(_name) \
280	struct driver_attribute driver_attr_##_name = __ATTR_WO(_name)
281
282extern int __must_check driver_create_file(struct device_driver *driver,
283					const struct driver_attribute *attr);
284extern void driver_remove_file(struct device_driver *driver,
285			       const struct driver_attribute *attr);
286
287extern int __must_check driver_for_each_device(struct device_driver *drv,
288					       struct device *start,
289					       void *data,
290					       int (*fn)(struct device *dev,
291							 void *));
292struct device *driver_find_device(struct device_driver *drv,
293				  struct device *start, void *data,
294				  int (*match)(struct device *dev, void *data));
295
296/**
297 * struct subsys_interface - interfaces to device functions
298 * @name:       name of the device function
299 * @subsys:     subsytem of the devices to attach to
300 * @node:       the list of functions registered at the subsystem
301 * @add_dev:    device hookup to device function handler
302 * @remove_dev: device hookup to device function handler
303 *
304 * Simple interfaces attached to a subsystem. Multiple interfaces can
305 * attach to a subsystem and its devices. Unlike drivers, they do not
306 * exclusively claim or control devices. Interfaces usually represent
307 * a specific functionality of a subsystem/class of devices.
308 */
309struct subsys_interface {
310	const char *name;
311	struct bus_type *subsys;
312	struct list_head node;
313	int (*add_dev)(struct device *dev, struct subsys_interface *sif);
314	int (*remove_dev)(struct device *dev, struct subsys_interface *sif);
315};
316
317int subsys_interface_register(struct subsys_interface *sif);
318void subsys_interface_unregister(struct subsys_interface *sif);
319
320int subsys_system_register(struct bus_type *subsys,
321			   const struct attribute_group **groups);
322int subsys_virtual_register(struct bus_type *subsys,
323			    const struct attribute_group **groups);
324
325/**
326 * struct class - device classes
327 * @name:	Name of the class.
328 * @owner:	The module owner.
329 * @class_attrs: Default attributes of this class.
330 * @dev_groups:	Default attributes of the devices that belong to the class.
331 * @dev_kobj:	The kobject that represents this class and links it into the hierarchy.
332 * @dev_uevent:	Called when a device is added, removed from this class, or a
333 *		few other things that generate uevents to add the environment
334 *		variables.
335 * @devnode:	Callback to provide the devtmpfs.
336 * @class_release: Called to release this class.
337 * @dev_release: Called to release the device.
338 * @suspend:	Used to put the device to sleep mode, usually to a low power
339 *		state.
340 * @resume:	Used to bring the device from the sleep mode.
341 * @ns_type:	Callbacks so sysfs can detemine namespaces.
342 * @namespace:	Namespace of the device belongs to this class.
343 * @pm:		The default device power management operations of this class.
344 * @p:		The private data of the driver core, no one other than the
345 *		driver core can touch this.
346 *
347 * A class is a higher-level view of a device that abstracts out low-level
348 * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
349 * at the class level, they are all simply disks. Classes allow user space
350 * to work with devices based on what they do, rather than how they are
351 * connected or how they work.
352 */
353struct class {
354	const char		*name;
355	struct module		*owner;
356
357	struct class_attribute		*class_attrs;
358	const struct attribute_group	**dev_groups;
359	struct kobject			*dev_kobj;
360
361	int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
362	char *(*devnode)(struct device *dev, umode_t *mode);
363
364	void (*class_release)(struct class *class);
365	void (*dev_release)(struct device *dev);
366
367	int (*suspend)(struct device *dev, pm_message_t state);
368	int (*resume)(struct device *dev);
369
370	const struct kobj_ns_type_operations *ns_type;
371	const void *(*namespace)(struct device *dev);
372
373	const struct dev_pm_ops *pm;
374
375	struct subsys_private *p;
376};
377
378struct class_dev_iter {
379	struct klist_iter		ki;
380	const struct device_type	*type;
381};
382
383extern struct kobject *sysfs_dev_block_kobj;
384extern struct kobject *sysfs_dev_char_kobj;
385extern int __must_check __class_register(struct class *class,
386					 struct lock_class_key *key);
387extern void class_unregister(struct class *class);
388
389/* This is a #define to keep the compiler from merging different
390 * instances of the __key variable */
391#define class_register(class)			\
392({						\
393	static struct lock_class_key __key;	\
394	__class_register(class, &__key);	\
395})
396
397struct class_compat;
398struct class_compat *class_compat_register(const char *name);
399void class_compat_unregister(struct class_compat *cls);
400int class_compat_create_link(struct class_compat *cls, struct device *dev,
401			     struct device *device_link);
402void class_compat_remove_link(struct class_compat *cls, struct device *dev,
403			      struct device *device_link);
404
405extern void class_dev_iter_init(struct class_dev_iter *iter,
406				struct class *class,
407				struct device *start,
408				const struct device_type *type);
409extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
410extern void class_dev_iter_exit(struct class_dev_iter *iter);
411
412extern int class_for_each_device(struct class *class, struct device *start,
413				 void *data,
414				 int (*fn)(struct device *dev, void *data));
415extern struct device *class_find_device(struct class *class,
416					struct device *start, const void *data,
417					int (*match)(struct device *, const void *));
418
419struct class_attribute {
420	struct attribute attr;
421	ssize_t (*show)(struct class *class, struct class_attribute *attr,
422			char *buf);
423	ssize_t (*store)(struct class *class, struct class_attribute *attr,
424			const char *buf, size_t count);
425};
426
427#define CLASS_ATTR(_name, _mode, _show, _store) \
428	struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
429#define CLASS_ATTR_RW(_name) \
430	struct class_attribute class_attr_##_name = __ATTR_RW(_name)
431#define CLASS_ATTR_RO(_name) \
432	struct class_attribute class_attr_##_name = __ATTR_RO(_name)
433
434extern int __must_check class_create_file_ns(struct class *class,
435					     const struct class_attribute *attr,
436					     const void *ns);
437extern void class_remove_file_ns(struct class *class,
438				 const struct class_attribute *attr,
439				 const void *ns);
440
441static inline int __must_check class_create_file(struct class *class,
442					const struct class_attribute *attr)
443{
444	return class_create_file_ns(class, attr, NULL);
445}
446
447static inline void class_remove_file(struct class *class,
448				     const struct class_attribute *attr)
449{
450	return class_remove_file_ns(class, attr, NULL);
451}
452
453/* Simple class attribute that is just a static string */
454struct class_attribute_string {
455	struct class_attribute attr;
456	char *str;
457};
458
459/* Currently read-only only */
460#define _CLASS_ATTR_STRING(_name, _mode, _str) \
461	{ __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
462#define CLASS_ATTR_STRING(_name, _mode, _str) \
463	struct class_attribute_string class_attr_##_name = \
464		_CLASS_ATTR_STRING(_name, _mode, _str)
465
466extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
467                        char *buf);
468
469struct class_interface {
470	struct list_head	node;
471	struct class		*class;
472
473	int (*add_dev)		(struct device *, struct class_interface *);
474	void (*remove_dev)	(struct device *, struct class_interface *);
475};
476
477extern int __must_check class_interface_register(struct class_interface *);
478extern void class_interface_unregister(struct class_interface *);
479
480extern struct class * __must_check __class_create(struct module *owner,
481						  const char *name,
482						  struct lock_class_key *key);
483extern void class_destroy(struct class *cls);
484
485/* This is a #define to keep the compiler from merging different
486 * instances of the __key variable */
487#define class_create(owner, name)		\
488({						\
489	static struct lock_class_key __key;	\
490	__class_create(owner, name, &__key);	\
491})
492
493/*
494 * The type of device, "struct device" is embedded in. A class
495 * or bus can contain devices of different types
496 * like "partitions" and "disks", "mouse" and "event".
497 * This identifies the device type and carries type-specific
498 * information, equivalent to the kobj_type of a kobject.
499 * If "name" is specified, the uevent will contain it in
500 * the DEVTYPE variable.
501 */
502struct device_type {
503	const char *name;
504	const struct attribute_group **groups;
505	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
506	char *(*devnode)(struct device *dev, umode_t *mode,
507			 kuid_t *uid, kgid_t *gid);
508	void (*release)(struct device *dev);
509
510	const struct dev_pm_ops *pm;
511};
512
513/* interface for exporting device attributes */
514struct device_attribute {
515	struct attribute	attr;
516	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
517			char *buf);
518	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
519			 const char *buf, size_t count);
520};
521
522struct dev_ext_attribute {
523	struct device_attribute attr;
524	void *var;
525};
526
527ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
528			  char *buf);
529ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
530			   const char *buf, size_t count);
531ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
532			char *buf);
533ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
534			 const char *buf, size_t count);
535ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
536			char *buf);
537ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
538			 const char *buf, size_t count);
539
540#define DEVICE_ATTR(_name, _mode, _show, _store) \
541	struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
542#define DEVICE_ATTR_RW(_name) \
543	struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
544#define DEVICE_ATTR_RO(_name) \
545	struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
546#define DEVICE_ATTR_WO(_name) \
547	struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
548#define DEVICE_ULONG_ATTR(_name, _mode, _var) \
549	struct dev_ext_attribute dev_attr_##_name = \
550		{ __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
551#define DEVICE_INT_ATTR(_name, _mode, _var) \
552	struct dev_ext_attribute dev_attr_##_name = \
553		{ __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
554#define DEVICE_BOOL_ATTR(_name, _mode, _var) \
555	struct dev_ext_attribute dev_attr_##_name = \
556		{ __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
557#define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
558	struct device_attribute dev_attr_##_name =		\
559		__ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
560
561extern int device_create_file(struct device *device,
562			      const struct device_attribute *entry);
563extern void device_remove_file(struct device *dev,
564			       const struct device_attribute *attr);
565extern bool device_remove_file_self(struct device *dev,
566				    const struct device_attribute *attr);
567extern int __must_check device_create_bin_file(struct device *dev,
568					const struct bin_attribute *attr);
569extern void device_remove_bin_file(struct device *dev,
570				   const struct bin_attribute *attr);
571
572/* device resource management */
573typedef void (*dr_release_t)(struct device *dev, void *res);
574typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
575
576#ifdef CONFIG_DEBUG_DEVRES
577extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
578			     const char *name);
579#define devres_alloc(release, size, gfp) \
580	__devres_alloc(release, size, gfp, #release)
581#else
582extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
583#endif
584extern void devres_for_each_res(struct device *dev, dr_release_t release,
585				dr_match_t match, void *match_data,
586				void (*fn)(struct device *, void *, void *),
587				void *data);
588extern void devres_free(void *res);
589extern void devres_add(struct device *dev, void *res);
590extern void *devres_find(struct device *dev, dr_release_t release,
591			 dr_match_t match, void *match_data);
592extern void *devres_get(struct device *dev, void *new_res,
593			dr_match_t match, void *match_data);
594extern void *devres_remove(struct device *dev, dr_release_t release,
595			   dr_match_t match, void *match_data);
596extern int devres_destroy(struct device *dev, dr_release_t release,
597			  dr_match_t match, void *match_data);
598extern int devres_release(struct device *dev, dr_release_t release,
599			  dr_match_t match, void *match_data);
600
601/* devres group */
602extern void * __must_check devres_open_group(struct device *dev, void *id,
603					     gfp_t gfp);
604extern void devres_close_group(struct device *dev, void *id);
605extern void devres_remove_group(struct device *dev, void *id);
606extern int devres_release_group(struct device *dev, void *id);
607
608/* managed devm_k.alloc/kfree for device drivers */
609extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp);
610extern char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt,
611			     va_list ap);
612extern __printf(3, 4)
613char *devm_kasprintf(struct device *dev, gfp_t gfp, const char *fmt, ...);
614static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
615{
616	return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
617}
618static inline void *devm_kmalloc_array(struct device *dev,
619				       size_t n, size_t size, gfp_t flags)
620{
621	if (size != 0 && n > SIZE_MAX / size)
622		return NULL;
623	return devm_kmalloc(dev, n * size, flags);
624}
625static inline void *devm_kcalloc(struct device *dev,
626				 size_t n, size_t size, gfp_t flags)
627{
628	return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
629}
630extern void devm_kfree(struct device *dev, void *p);
631extern char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp);
632extern void *devm_kmemdup(struct device *dev, const void *src, size_t len,
633			  gfp_t gfp);
634
635extern unsigned long devm_get_free_pages(struct device *dev,
636					 gfp_t gfp_mask, unsigned int order);
637extern void devm_free_pages(struct device *dev, unsigned long addr);
638
639void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
640
641/* allows to add/remove a custom action to devres stack */
642int devm_add_action(struct device *dev, void (*action)(void *), void *data);
643void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
644
645struct device_dma_parameters {
646	/*
647	 * a low level driver may set these to teach IOMMU code about
648	 * sg limitations.
649	 */
650	unsigned int max_segment_size;
651	unsigned long segment_boundary_mask;
652};
653
654/**
655 * struct device - The basic device structure
656 * @parent:	The device's "parent" device, the device to which it is attached.
657 * 		In most cases, a parent device is some sort of bus or host
658 * 		controller. If parent is NULL, the device, is a top-level device,
659 * 		which is not usually what you want.
660 * @p:		Holds the private data of the driver core portions of the device.
661 * 		See the comment of the struct device_private for detail.
662 * @kobj:	A top-level, abstract class from which other classes are derived.
663 * @init_name:	Initial name of the device.
664 * @type:	The type of device.
665 * 		This identifies the device type and carries type-specific
666 * 		information.
667 * @mutex:	Mutex to synchronize calls to its driver.
668 * @bus:	Type of bus device is on.
669 * @driver:	Which driver has allocated this
670 * @platform_data: Platform data specific to the device.
671 * 		Example: For devices on custom boards, as typical of embedded
672 * 		and SOC based hardware, Linux often uses platform_data to point
673 * 		to board-specific structures describing devices and how they
674 * 		are wired.  That can include what ports are available, chip
675 * 		variants, which GPIO pins act in what additional roles, and so
676 * 		on.  This shrinks the "Board Support Packages" (BSPs) and
677 * 		minimizes board-specific #ifdefs in drivers.
678 * @driver_data: Private pointer for driver specific info.
679 * @power:	For device power management.
680 * 		See Documentation/power/devices.txt for details.
681 * @pm_domain:	Provide callbacks that are executed during system suspend,
682 * 		hibernation, system resume and during runtime PM transitions
683 * 		along with subsystem-level and driver-level callbacks.
684 * @pins:	For device pin management.
685 *		See Documentation/pinctrl.txt for details.
686 * @numa_node:	NUMA node this device is close to.
687 * @dma_mask:	Dma mask (if dma'ble device).
688 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
689 * 		hardware supports 64-bit addresses for consistent allocations
690 * 		such descriptors.
691 * @dma_pfn_offset: offset of DMA memory range relatively of RAM
692 * @dma_parms:	A low level driver may set these to teach IOMMU code about
693 * 		segment limitations.
694 * @dma_pools:	Dma pools (if dma'ble device).
695 * @dma_mem:	Internal for coherent mem override.
696 * @cma_area:	Contiguous memory area for dma allocations
697 * @archdata:	For arch-specific additions.
698 * @of_node:	Associated device tree node.
699 * @fwnode:	Associated device node supplied by platform firmware.
700 * @devt:	For creating the sysfs "dev".
701 * @id:		device instance
702 * @devres_lock: Spinlock to protect the resource of the device.
703 * @devres_head: The resources list of the device.
704 * @knode_class: The node used to add the device to the class list.
705 * @class:	The class of the device.
706 * @groups:	Optional attribute groups.
707 * @release:	Callback to free the device after all references have
708 * 		gone away. This should be set by the allocator of the
709 * 		device (i.e. the bus driver that discovered the device).
710 * @iommu_group: IOMMU group the device belongs to.
711 *
712 * @offline_disabled: If set, the device is permanently online.
713 * @offline:	Set after successful invocation of bus type's .offline().
714 *
715 * At the lowest level, every device in a Linux system is represented by an
716 * instance of struct device. The device structure contains the information
717 * that the device model core needs to model the system. Most subsystems,
718 * however, track additional information about the devices they host. As a
719 * result, it is rare for devices to be represented by bare device structures;
720 * instead, that structure, like kobject structures, is usually embedded within
721 * a higher-level representation of the device.
722 */
723struct device {
724	struct device		*parent;
725
726	struct device_private	*p;
727
728	struct kobject kobj;
729	const char		*init_name; /* initial name of the device */
730	const struct device_type *type;
731
732	struct mutex		mutex;	/* mutex to synchronize calls to
733					 * its driver.
734					 */
735
736	struct bus_type	*bus;		/* type of bus device is on */
737	struct device_driver *driver;	/* which driver has allocated this
738					   device */
739	void		*platform_data;	/* Platform specific data, device
740					   core doesn't touch it */
741	void		*driver_data;	/* Driver data, set and get with
742					   dev_set/get_drvdata */
743	struct dev_pm_info	power;
744	struct dev_pm_domain	*pm_domain;
745
746#ifdef CONFIG_PINCTRL
747	struct dev_pin_info	*pins;
748#endif
749
750#ifdef CONFIG_NUMA
751	int		numa_node;	/* NUMA node this device is close to */
752#endif
753	u64		*dma_mask;	/* dma mask (if dma'able device) */
754	u64		coherent_dma_mask;/* Like dma_mask, but for
755					     alloc_coherent mappings as
756					     not all hardware supports
757					     64 bit addresses for consistent
758					     allocations such descriptors. */
759	unsigned long	dma_pfn_offset;
760
761	struct device_dma_parameters *dma_parms;
762
763	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
764
765	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
766					     override */
767#ifdef CONFIG_DMA_CMA
768	struct cma *cma_area;		/* contiguous memory area for dma
769					   allocations */
770#endif
771	/* arch specific additions */
772	struct dev_archdata	archdata;
773
774	struct device_node	*of_node; /* associated device tree node */
775	struct fwnode_handle	*fwnode; /* firmware device node */
776
777	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
778	u32			id;	/* device instance */
779
780	spinlock_t		devres_lock;
781	struct list_head	devres_head;
782
783	struct klist_node	knode_class;
784	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
790	bool			offline_disabled:1;
791	bool			offline:1;
792};
793
794static inline struct device *kobj_to_dev(struct kobject *kobj)
795{
796	return container_of(kobj, struct device, kobj);
797}
798
799/* Get the wakeup routines, which depend on struct device */
800#include <linux/pm_wakeup.h>
801
802static inline const char *dev_name(const struct device *dev)
803{
804	/* Use the init name until the kobject becomes available */
805	if (dev->init_name)
806		return dev->init_name;
807
808	return kobject_name(&dev->kobj);
809}
810
811extern __printf(2, 3)
812int dev_set_name(struct device *dev, const char *name, ...);
813
814#ifdef CONFIG_NUMA
815static inline int dev_to_node(struct device *dev)
816{
817	return dev->numa_node;
818}
819static inline void set_dev_node(struct device *dev, int node)
820{
821	dev->numa_node = node;
822}
823#else
824static inline int dev_to_node(struct device *dev)
825{
826	return -1;
827}
828static inline void set_dev_node(struct device *dev, int node)
829{
830}
831#endif
832
833static inline void *dev_get_drvdata(const struct device *dev)
834{
835	return dev->driver_data;
836}
837
838static inline void dev_set_drvdata(struct device *dev, void *data)
839{
840	dev->driver_data = data;
841}
842
843static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
844{
845	return dev ? dev->power.subsys_data : NULL;
846}
847
848static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
849{
850	return dev->kobj.uevent_suppress;
851}
852
853static inline void dev_set_uevent_suppress(struct device *dev, int val)
854{
855	dev->kobj.uevent_suppress = val;
856}
857
858static inline int device_is_registered(struct device *dev)
859{
860	return dev->kobj.state_in_sysfs;
861}
862
863static inline void device_enable_async_suspend(struct device *dev)
864{
865	if (!dev->power.is_prepared)
866		dev->power.async_suspend = true;
867}
868
869static inline void device_disable_async_suspend(struct device *dev)
870{
871	if (!dev->power.is_prepared)
872		dev->power.async_suspend = false;
873}
874
875static inline bool device_async_suspend_enabled(struct device *dev)
876{
877	return !!dev->power.async_suspend;
878}
879
880static inline void pm_suspend_ignore_children(struct device *dev, bool enable)
881{
882	dev->power.ignore_children = enable;
883}
884
885static inline void dev_pm_syscore_device(struct device *dev, bool val)
886{
887#ifdef CONFIG_PM_SLEEP
888	dev->power.syscore = val;
889#endif
890}
891
892static inline void device_lock(struct device *dev)
893{
894	mutex_lock(&dev->mutex);
895}
896
897static inline int device_trylock(struct device *dev)
898{
899	return mutex_trylock(&dev->mutex);
900}
901
902static inline void device_unlock(struct device *dev)
903{
904	mutex_unlock(&dev->mutex);
905}
906
907static inline void device_lock_assert(struct device *dev)
908{
909	lockdep_assert_held(&dev->mutex);
910}
911
912static inline struct device_node *dev_of_node(struct device *dev)
913{
914	if (!IS_ENABLED(CONFIG_OF))
915		return NULL;
916	return dev->of_node;
917}
918
919void driver_init(void);
920
921/*
922 * High level routines for use by the bus drivers
923 */
924extern int __must_check device_register(struct device *dev);
925extern void device_unregister(struct device *dev);
926extern void device_initialize(struct device *dev);
927extern int __must_check device_add(struct device *dev);
928extern void device_del(struct device *dev);
929extern int device_for_each_child(struct device *dev, void *data,
930		     int (*fn)(struct device *dev, void *data));
931extern struct device *device_find_child(struct device *dev, void *data,
932				int (*match)(struct device *dev, void *data));
933extern int device_rename(struct device *dev, const char *new_name);
934extern int device_move(struct device *dev, struct device *new_parent,
935		       enum dpm_order dpm_order);
936extern const char *device_get_devnode(struct device *dev,
937				      umode_t *mode, kuid_t *uid, kgid_t *gid,
938				      const char **tmp);
939
940static inline bool device_supports_offline(struct device *dev)
941{
942	return dev->bus && dev->bus->offline && dev->bus->online;
943}
944
945extern void lock_device_hotplug(void);
946extern void unlock_device_hotplug(void);
947extern int lock_device_hotplug_sysfs(void);
948extern int device_offline(struct device *dev);
949extern int device_online(struct device *dev);
950extern void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
951extern void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
952
953/*
954 * Root device objects for grouping under /sys/devices
955 */
956extern struct device *__root_device_register(const char *name,
957					     struct module *owner);
958
959/* This is a macro to avoid include problems with THIS_MODULE */
960#define root_device_register(name) \
961	__root_device_register(name, THIS_MODULE)
962
963extern void root_device_unregister(struct device *root);
964
965static inline void *dev_get_platdata(const struct device *dev)
966{
967	return dev->platform_data;
968}
969
970/*
971 * Manual binding of a device to driver. See drivers/base/bus.c
972 * for information on use.
973 */
974extern int __must_check device_bind_driver(struct device *dev);
975extern void device_release_driver(struct device *dev);
976extern int  __must_check device_attach(struct device *dev);
977extern int __must_check driver_attach(struct device_driver *drv);
978extern int __must_check device_reprobe(struct device *dev);
979
980/*
981 * Easy functions for dynamically creating devices on the fly
982 */
983extern struct device *device_create_vargs(struct class *cls,
984					  struct device *parent,
985					  dev_t devt,
986					  void *drvdata,
987					  const char *fmt,
988					  va_list vargs);
989extern __printf(5, 6)
990struct device *device_create(struct class *cls, struct device *parent,
991			     dev_t devt, void *drvdata,
992			     const char *fmt, ...);
993extern __printf(6, 7)
994struct device *device_create_with_groups(struct class *cls,
995			     struct device *parent, dev_t devt, void *drvdata,
996			     const struct attribute_group **groups,
997			     const char *fmt, ...);
998extern void device_destroy(struct class *cls, dev_t devt);
999
1000/*
1001 * Platform "fixup" functions - allow the platform to have their say
1002 * about devices and actions that the general device layer doesn't
1003 * know about.
1004 */
1005/* Notify platform of device discovery */
1006extern int (*platform_notify)(struct device *dev);
1007
1008extern int (*platform_notify_remove)(struct device *dev);
1009
1010
1011/*
1012 * get_device - atomically increment the reference count for the device.
1013 *
1014 */
1015extern struct device *get_device(struct device *dev);
1016extern void put_device(struct device *dev);
1017
1018#ifdef CONFIG_DEVTMPFS
1019extern int devtmpfs_create_node(struct device *dev);
1020extern int devtmpfs_delete_node(struct device *dev);
1021extern int devtmpfs_mount(const char *mntdir);
1022#else
1023static inline int devtmpfs_create_node(struct device *dev) { return 0; }
1024static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
1025static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
1026#endif
1027
1028/* drivers/base/power/shutdown.c */
1029extern void device_shutdown(void);
1030
1031/* debugging and troubleshooting/diagnostic helpers. */
1032extern const char *dev_driver_string(const struct device *dev);
1033
1034
1035#ifdef CONFIG_PRINTK
1036
1037extern __printf(3, 0)
1038int dev_vprintk_emit(int level, const struct device *dev,
1039		     const char *fmt, va_list args);
1040extern __printf(3, 4)
1041int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...);
1042
1043extern __printf(3, 4)
1044void dev_printk(const char *level, const struct device *dev,
1045		const char *fmt, ...);
1046extern __printf(2, 3)
1047void dev_emerg(const struct device *dev, const char *fmt, ...);
1048extern __printf(2, 3)
1049void dev_alert(const struct device *dev, const char *fmt, ...);
1050extern __printf(2, 3)
1051void dev_crit(const struct device *dev, const char *fmt, ...);
1052extern __printf(2, 3)
1053void dev_err(const struct device *dev, const char *fmt, ...);
1054extern __printf(2, 3)
1055void dev_warn(const struct device *dev, const char *fmt, ...);
1056extern __printf(2, 3)
1057void dev_notice(const struct device *dev, const char *fmt, ...);
1058extern __printf(2, 3)
1059void _dev_info(const struct device *dev, const char *fmt, ...);
1060
1061#else
1062
1063static inline __printf(3, 0)
1064int dev_vprintk_emit(int level, const struct device *dev,
1065		     const char *fmt, va_list args)
1066{ return 0; }
1067static inline __printf(3, 4)
1068int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
1069{ return 0; }
1070
1071static inline void __dev_printk(const char *level, const struct device *dev,
1072				struct va_format *vaf)
1073{}
1074static inline __printf(3, 4)
1075void dev_printk(const char *level, const struct device *dev,
1076		const char *fmt, ...)
1077{}
1078
1079static inline __printf(2, 3)
1080void dev_emerg(const struct device *dev, const char *fmt, ...)
1081{}
1082static inline __printf(2, 3)
1083void dev_crit(const struct device *dev, const char *fmt, ...)
1084{}
1085static inline __printf(2, 3)
1086void dev_alert(const struct device *dev, const char *fmt, ...)
1087{}
1088static inline __printf(2, 3)
1089void dev_err(const struct device *dev, const char *fmt, ...)
1090{}
1091static inline __printf(2, 3)
1092void dev_warn(const struct device *dev, const char *fmt, ...)
1093{}
1094static inline __printf(2, 3)
1095void dev_notice(const struct device *dev, const char *fmt, ...)
1096{}
1097static inline __printf(2, 3)
1098void _dev_info(const struct device *dev, const char *fmt, ...)
1099{}
1100
1101#endif
1102
1103/*
1104 * Stupid hackaround for existing uses of non-printk uses dev_info
1105 *
1106 * Note that the definition of dev_info below is actually _dev_info
1107 * and a macro is used to avoid redefining dev_info
1108 */
1109
1110#define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)
1111
1112#if defined(CONFIG_DYNAMIC_DEBUG)
1113#define dev_dbg(dev, format, ...)		     \
1114do {						     \
1115	dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
1116} while (0)
1117#elif defined(DEBUG)
1118#define dev_dbg(dev, format, arg...)		\
1119	dev_printk(KERN_DEBUG, dev, format, ##arg)
1120#else
1121#define dev_dbg(dev, format, arg...)				\
1122({								\
1123	if (0)							\
1124		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
1125})
1126#endif
1127
1128#ifdef CONFIG_PRINTK
1129#define dev_level_once(dev_level, dev, fmt, ...)			\
1130do {									\
1131	static bool __print_once __read_mostly;				\
1132									\
1133	if (!__print_once) {						\
1134		__print_once = true;					\
1135		dev_level(dev, fmt, ##__VA_ARGS__);			\
1136	}								\
1137} while (0)
1138#else
1139#define dev_level_once(dev_level, dev, fmt, ...)			\
1140do {									\
1141	if (0)								\
1142		dev_level(dev, fmt, ##__VA_ARGS__);			\
1143} while (0)
1144#endif
1145
1146#define dev_emerg_once(dev, fmt, ...)					\
1147	dev_level_once(dev_emerg, dev, fmt, ##__VA_ARGS__)
1148#define dev_alert_once(dev, fmt, ...)					\
1149	dev_level_once(dev_alert, dev, fmt, ##__VA_ARGS__)
1150#define dev_crit_once(dev, fmt, ...)					\
1151	dev_level_once(dev_crit, dev, fmt, ##__VA_ARGS__)
1152#define dev_err_once(dev, fmt, ...)					\
1153	dev_level_once(dev_err, dev, fmt, ##__VA_ARGS__)
1154#define dev_warn_once(dev, fmt, ...)					\
1155	dev_level_once(dev_warn, dev, fmt, ##__VA_ARGS__)
1156#define dev_notice_once(dev, fmt, ...)					\
1157	dev_level_once(dev_notice, dev, fmt, ##__VA_ARGS__)
1158#define dev_info_once(dev, fmt, ...)					\
1159	dev_level_once(dev_info, dev, fmt, ##__VA_ARGS__)
1160#define dev_dbg_once(dev, fmt, ...)					\
1161	dev_level_once(dev_dbg, dev, fmt, ##__VA_ARGS__)
1162
1163#define dev_level_ratelimited(dev_level, dev, fmt, ...)			\
1164do {									\
1165	static DEFINE_RATELIMIT_STATE(_rs,				\
1166				      DEFAULT_RATELIMIT_INTERVAL,	\
1167				      DEFAULT_RATELIMIT_BURST);		\
1168	if (__ratelimit(&_rs))						\
1169		dev_level(dev, fmt, ##__VA_ARGS__);			\
1170} while (0)
1171
1172#define dev_emerg_ratelimited(dev, fmt, ...)				\
1173	dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__)
1174#define dev_alert_ratelimited(dev, fmt, ...)				\
1175	dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__)
1176#define dev_crit_ratelimited(dev, fmt, ...)				\
1177	dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__)
1178#define dev_err_ratelimited(dev, fmt, ...)				\
1179	dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__)
1180#define dev_warn_ratelimited(dev, fmt, ...)				\
1181	dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__)
1182#define dev_notice_ratelimited(dev, fmt, ...)				\
1183	dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__)
1184#define dev_info_ratelimited(dev, fmt, ...)				\
1185	dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__)
1186#if defined(CONFIG_DYNAMIC_DEBUG)
1187/* descriptor check is first to prevent flooding with "callbacks suppressed" */
1188#define dev_dbg_ratelimited(dev, fmt, ...)				\
1189do {									\
1190	static DEFINE_RATELIMIT_STATE(_rs,				\
1191				      DEFAULT_RATELIMIT_INTERVAL,	\
1192				      DEFAULT_RATELIMIT_BURST);		\
1193	DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);			\
1194	if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) &&	\
1195	    __ratelimit(&_rs))						\
1196		__dynamic_dev_dbg(&descriptor, dev, fmt,		\
1197				  ##__VA_ARGS__);			\
1198} while (0)
1199#elif defined(DEBUG)
1200#define dev_dbg_ratelimited(dev, fmt, ...)				\
1201do {									\
1202	static DEFINE_RATELIMIT_STATE(_rs,				\
1203				      DEFAULT_RATELIMIT_INTERVAL,	\
1204				      DEFAULT_RATELIMIT_BURST);		\
1205	if (__ratelimit(&_rs))						\
1206		dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__);	\
1207} while (0)
1208#else
1209#define dev_dbg_ratelimited(dev, fmt, ...)			\
1210	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
1211#endif
1212
1213#ifdef VERBOSE_DEBUG
1214#define dev_vdbg	dev_dbg
1215#else
1216#define dev_vdbg(dev, format, arg...)				\
1217({								\
1218	if (0)							\
1219		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
1220})
1221#endif
1222
1223/*
1224 * dev_WARN*() acts like dev_printk(), but with the key difference of
1225 * using WARN/WARN_ONCE to include file/line information and a backtrace.
1226 */
1227#define dev_WARN(dev, format, arg...) \
1228	WARN(1, "%s %s: " format, dev_driver_string(dev), dev_name(dev), ## arg);
1229
1230#define dev_WARN_ONCE(dev, condition, format, arg...) \
1231	WARN_ONCE(condition, "%s %s: " format, \
1232			dev_driver_string(dev), dev_name(dev), ## arg)
1233
1234/* Create alias, so I can be autoloaded. */
1235#define MODULE_ALIAS_CHARDEV(major,minor) \
1236	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1237#define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1238	MODULE_ALIAS("char-major-" __stringify(major) "-*")
1239
1240#ifdef CONFIG_SYSFS_DEPRECATED
1241extern long sysfs_deprecated;
1242#else
1243#define sysfs_deprecated 0
1244#endif
1245
1246/**
1247 * module_driver() - Helper macro for drivers that don't do anything
1248 * special in module init/exit. This eliminates a lot of boilerplate.
1249 * Each module may only use this macro once, and calling it replaces
1250 * module_init() and module_exit().
1251 *
1252 * @__driver: driver name
1253 * @__register: register function for this driver type
1254 * @__unregister: unregister function for this driver type
1255 * @...: Additional arguments to be passed to __register and __unregister.
1256 *
1257 * Use this macro to construct bus specific macros for registering
1258 * drivers, and do not use it on its own.
1259 */
1260#define module_driver(__driver, __register, __unregister, ...) \
1261static int __init __driver##_init(void) \
1262{ \
1263	return __register(&(__driver) , ##__VA_ARGS__); \
1264} \
1265module_init(__driver##_init); \
1266static void __exit __driver##_exit(void) \
1267{ \
1268	__unregister(&(__driver) , ##__VA_ARGS__); \
1269} \
1270module_exit(__driver##_exit);
1271
1272#endif /* _DEVICE_H_ */
1273