xref: /openbmc/linux/include/linux/device.h (revision d894fc60)
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 
32 struct device;
33 struct device_private;
34 struct device_driver;
35 struct driver_private;
36 struct module;
37 struct class;
38 struct subsys_private;
39 struct bus_type;
40 struct device_node;
41 struct iommu_ops;
42 struct iommu_group;
43 
44 struct bus_attribute {
45 	struct attribute	attr;
46 	ssize_t (*show)(struct bus_type *bus, char *buf);
47 	ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
48 };
49 
50 #define BUS_ATTR(_name, _mode, _show, _store)	\
51 	struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)
52 #define BUS_ATTR_RW(_name) \
53 	struct bus_attribute bus_attr_##_name = __ATTR_RW(_name)
54 #define BUS_ATTR_RO(_name) \
55 	struct bus_attribute bus_attr_##_name = __ATTR_RO(_name)
56 
57 extern int __must_check bus_create_file(struct bus_type *,
58 					struct bus_attribute *);
59 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
60 
61 /**
62  * struct bus_type - The bus type of the device
63  *
64  * @name:	The name of the bus.
65  * @dev_name:	Used for subsystems to enumerate devices like ("foo%u", dev->id).
66  * @dev_root:	Default device to use as the parent.
67  * @dev_attrs:	Default attributes of the devices on the bus.
68  * @bus_groups:	Default attributes of the bus.
69  * @dev_groups:	Default attributes of the devices on the bus.
70  * @drv_groups: Default attributes of the device drivers on the bus.
71  * @match:	Called, perhaps multiple times, whenever a new device or driver
72  *		is added for this bus. It should return a nonzero value if the
73  *		given device can be handled by the given driver.
74  * @uevent:	Called when a device is added, removed, or a few other things
75  *		that generate uevents to add the environment variables.
76  * @probe:	Called when a new device or driver add to this bus, and callback
77  *		the specific driver's probe to initial the matched device.
78  * @remove:	Called when a device removed from this bus.
79  * @shutdown:	Called at shut-down time to quiesce the device.
80  *
81  * @online:	Called to put the device back online (after offlining it).
82  * @offline:	Called to put the device offline for hot-removal. May fail.
83  *
84  * @suspend:	Called when a device on this bus wants to go to sleep mode.
85  * @resume:	Called to bring a device on this bus out of sleep mode.
86  * @pm:		Power management operations of this bus, callback the specific
87  *		device driver's pm-ops.
88  * @iommu_ops:  IOMMU specific operations for this bus, used to attach IOMMU
89  *              driver implementations to a bus and allow the driver to do
90  *              bus-specific setup
91  * @p:		The private data of the driver core, only the driver core can
92  *		touch this.
93  * @lock_key:	Lock class key for use by the lock validator
94  *
95  * A bus is a channel between the processor and one or more devices. For the
96  * purposes of the device model, all devices are connected via a bus, even if
97  * it is an internal, virtual, "platform" bus. Buses can plug into each other.
98  * A USB controller is usually a PCI device, for example. The device model
99  * represents the actual connections between buses and the devices they control.
100  * A bus is represented by the bus_type structure. It contains the name, the
101  * default attributes, the bus' methods, PM operations, and the driver core's
102  * private data.
103  */
104 struct bus_type {
105 	const char		*name;
106 	const char		*dev_name;
107 	struct device		*dev_root;
108 	struct device_attribute	*dev_attrs;	/* use dev_groups instead */
109 	const struct attribute_group **bus_groups;
110 	const struct attribute_group **dev_groups;
111 	const struct attribute_group **drv_groups;
112 
113 	int (*match)(struct device *dev, struct device_driver *drv);
114 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
115 	int (*probe)(struct device *dev);
116 	int (*remove)(struct device *dev);
117 	void (*shutdown)(struct device *dev);
118 
119 	int (*online)(struct device *dev);
120 	int (*offline)(struct device *dev);
121 
122 	int (*suspend)(struct device *dev, pm_message_t state);
123 	int (*resume)(struct device *dev);
124 
125 	const struct dev_pm_ops *pm;
126 
127 	const struct iommu_ops *iommu_ops;
128 
129 	struct subsys_private *p;
130 	struct lock_class_key lock_key;
131 };
132 
133 extern int __must_check bus_register(struct bus_type *bus);
134 
135 extern void bus_unregister(struct bus_type *bus);
136 
137 extern int __must_check bus_rescan_devices(struct bus_type *bus);
138 
139 /* iterator helpers for buses */
140 struct subsys_dev_iter {
141 	struct klist_iter		ki;
142 	const struct device_type	*type;
143 };
144 void subsys_dev_iter_init(struct subsys_dev_iter *iter,
145 			 struct bus_type *subsys,
146 			 struct device *start,
147 			 const struct device_type *type);
148 struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter);
149 void subsys_dev_iter_exit(struct subsys_dev_iter *iter);
150 
151 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
152 		     int (*fn)(struct device *dev, void *data));
153 struct device *bus_find_device(struct bus_type *bus, struct device *start,
154 			       void *data,
155 			       int (*match)(struct device *dev, void *data));
156 struct device *bus_find_device_by_name(struct bus_type *bus,
157 				       struct device *start,
158 				       const char *name);
159 struct device *subsys_find_device_by_id(struct bus_type *bus, unsigned int id,
160 					struct device *hint);
161 int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
162 		     void *data, int (*fn)(struct device_driver *, void *));
163 void bus_sort_breadthfirst(struct bus_type *bus,
164 			   int (*compare)(const struct device *a,
165 					  const struct device *b));
166 /*
167  * Bus notifiers: Get notified of addition/removal of devices
168  * and binding/unbinding of drivers to devices.
169  * In the long run, it should be a replacement for the platform
170  * notify hooks.
171  */
172 struct notifier_block;
173 
174 extern int bus_register_notifier(struct bus_type *bus,
175 				 struct notifier_block *nb);
176 extern int bus_unregister_notifier(struct bus_type *bus,
177 				   struct notifier_block *nb);
178 
179 /* All 4 notifers below get called with the target struct device *
180  * as an argument. Note that those functions are likely to be called
181  * with the device lock held in the core, so be careful.
182  */
183 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
184 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device to be removed */
185 #define BUS_NOTIFY_REMOVED_DEVICE	0x00000003 /* device removed */
186 #define BUS_NOTIFY_BIND_DRIVER		0x00000004 /* driver about to be
187 						      bound */
188 #define BUS_NOTIFY_BOUND_DRIVER		0x00000005 /* driver bound to device */
189 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000006 /* driver about to be
190 						      unbound */
191 #define BUS_NOTIFY_UNBOUND_DRIVER	0x00000007 /* driver is unbound
192 						      from the device */
193 
194 extern struct kset *bus_get_kset(struct bus_type *bus);
195 extern struct klist *bus_get_device_klist(struct bus_type *bus);
196 
197 /**
198  * struct device_driver - The basic device driver structure
199  * @name:	Name of the device driver.
200  * @bus:	The bus which the device of this driver belongs to.
201  * @owner:	The module owner.
202  * @mod_name:	Used for built-in modules.
203  * @suppress_bind_attrs: Disables bind/unbind via sysfs.
204  * @of_match_table: The open firmware table.
205  * @acpi_match_table: The ACPI match table.
206  * @probe:	Called to query the existence of a specific device,
207  *		whether this driver can work with it, and bind the driver
208  *		to a specific device.
209  * @remove:	Called when the device is removed from the system to
210  *		unbind a device from this driver.
211  * @shutdown:	Called at shut-down time to quiesce the device.
212  * @suspend:	Called to put the device to sleep mode. Usually to a
213  *		low power state.
214  * @resume:	Called to bring a device from sleep mode.
215  * @groups:	Default attributes that get created by the driver core
216  *		automatically.
217  * @pm:		Power management operations of the device which matched
218  *		this driver.
219  * @p:		Driver core's private data, no one other than the driver
220  *		core can touch this.
221  *
222  * The device driver-model tracks all of the drivers known to the system.
223  * The main reason for this tracking is to enable the driver core to match
224  * up drivers with new devices. Once drivers are known objects within the
225  * system, however, a number of other things become possible. Device drivers
226  * can export information and configuration variables that are independent
227  * of any specific device.
228  */
229 struct device_driver {
230 	const char		*name;
231 	struct bus_type		*bus;
232 
233 	struct module		*owner;
234 	const char		*mod_name;	/* used for built-in modules */
235 
236 	bool suppress_bind_attrs;	/* disables bind/unbind via sysfs */
237 
238 	const struct of_device_id	*of_match_table;
239 	const struct acpi_device_id	*acpi_match_table;
240 
241 	int (*probe) (struct device *dev);
242 	int (*remove) (struct device *dev);
243 	void (*shutdown) (struct device *dev);
244 	int (*suspend) (struct device *dev, pm_message_t state);
245 	int (*resume) (struct device *dev);
246 	const struct attribute_group **groups;
247 
248 	const struct dev_pm_ops *pm;
249 
250 	struct driver_private *p;
251 };
252 
253 
254 extern int __must_check driver_register(struct device_driver *drv);
255 extern void driver_unregister(struct device_driver *drv);
256 
257 extern struct device_driver *driver_find(const char *name,
258 					 struct bus_type *bus);
259 extern int driver_probe_done(void);
260 extern void wait_for_device_probe(void);
261 
262 
263 /* sysfs interface for exporting driver attributes */
264 
265 struct driver_attribute {
266 	struct attribute attr;
267 	ssize_t (*show)(struct device_driver *driver, char *buf);
268 	ssize_t (*store)(struct device_driver *driver, const char *buf,
269 			 size_t count);
270 };
271 
272 #define DRIVER_ATTR(_name, _mode, _show, _store) \
273 	struct driver_attribute driver_attr_##_name = __ATTR(_name, _mode, _show, _store)
274 #define DRIVER_ATTR_RW(_name) \
275 	struct driver_attribute driver_attr_##_name = __ATTR_RW(_name)
276 #define DRIVER_ATTR_RO(_name) \
277 	struct driver_attribute driver_attr_##_name = __ATTR_RO(_name)
278 #define DRIVER_ATTR_WO(_name) \
279 	struct driver_attribute driver_attr_##_name = __ATTR_WO(_name)
280 
281 extern int __must_check driver_create_file(struct device_driver *driver,
282 					const struct driver_attribute *attr);
283 extern void driver_remove_file(struct device_driver *driver,
284 			       const struct driver_attribute *attr);
285 
286 extern int __must_check driver_for_each_device(struct device_driver *drv,
287 					       struct device *start,
288 					       void *data,
289 					       int (*fn)(struct device *dev,
290 							 void *));
291 struct device *driver_find_device(struct device_driver *drv,
292 				  struct device *start, void *data,
293 				  int (*match)(struct device *dev, void *data));
294 
295 /**
296  * struct subsys_interface - interfaces to device functions
297  * @name:       name of the device function
298  * @subsys:     subsytem of the devices to attach to
299  * @node:       the list of functions registered at the subsystem
300  * @add_dev:    device hookup to device function handler
301  * @remove_dev: device hookup to device function handler
302  *
303  * Simple interfaces attached to a subsystem. Multiple interfaces can
304  * attach to a subsystem and its devices. Unlike drivers, they do not
305  * exclusively claim or control devices. Interfaces usually represent
306  * a specific functionality of a subsystem/class of devices.
307  */
308 struct subsys_interface {
309 	const char *name;
310 	struct bus_type *subsys;
311 	struct list_head node;
312 	int (*add_dev)(struct device *dev, struct subsys_interface *sif);
313 	int (*remove_dev)(struct device *dev, struct subsys_interface *sif);
314 };
315 
316 int subsys_interface_register(struct subsys_interface *sif);
317 void subsys_interface_unregister(struct subsys_interface *sif);
318 
319 int subsys_system_register(struct bus_type *subsys,
320 			   const struct attribute_group **groups);
321 int subsys_virtual_register(struct bus_type *subsys,
322 			    const struct attribute_group **groups);
323 
324 /**
325  * struct class - device classes
326  * @name:	Name of the class.
327  * @owner:	The module owner.
328  * @class_attrs: Default attributes of this class.
329  * @dev_groups:	Default attributes of the devices that belong to the class.
330  * @dev_kobj:	The kobject that represents this class and links it into the hierarchy.
331  * @dev_uevent:	Called when a device is added, removed from this class, or a
332  *		few other things that generate uevents to add the environment
333  *		variables.
334  * @devnode:	Callback to provide the devtmpfs.
335  * @class_release: Called to release this class.
336  * @dev_release: Called to release the device.
337  * @suspend:	Used to put the device to sleep mode, usually to a low power
338  *		state.
339  * @resume:	Used to bring the device from the sleep mode.
340  * @ns_type:	Callbacks so sysfs can detemine namespaces.
341  * @namespace:	Namespace of the device belongs to this class.
342  * @pm:		The default device power management operations of this class.
343  * @p:		The private data of the driver core, no one other than the
344  *		driver core can touch this.
345  *
346  * A class is a higher-level view of a device that abstracts out low-level
347  * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
348  * at the class level, they are all simply disks. Classes allow user space
349  * to work with devices based on what they do, rather than how they are
350  * connected or how they work.
351  */
352 struct class {
353 	const char		*name;
354 	struct module		*owner;
355 
356 	struct class_attribute		*class_attrs;
357 	const struct attribute_group	**dev_groups;
358 	struct kobject			*dev_kobj;
359 
360 	int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
361 	char *(*devnode)(struct device *dev, umode_t *mode);
362 
363 	void (*class_release)(struct class *class);
364 	void (*dev_release)(struct device *dev);
365 
366 	int (*suspend)(struct device *dev, pm_message_t state);
367 	int (*resume)(struct device *dev);
368 
369 	const struct kobj_ns_type_operations *ns_type;
370 	const void *(*namespace)(struct device *dev);
371 
372 	const struct dev_pm_ops *pm;
373 
374 	struct subsys_private *p;
375 };
376 
377 struct class_dev_iter {
378 	struct klist_iter		ki;
379 	const struct device_type	*type;
380 };
381 
382 extern struct kobject *sysfs_dev_block_kobj;
383 extern struct kobject *sysfs_dev_char_kobj;
384 extern int __must_check __class_register(struct class *class,
385 					 struct lock_class_key *key);
386 extern void class_unregister(struct class *class);
387 
388 /* This is a #define to keep the compiler from merging different
389  * instances of the __key variable */
390 #define class_register(class)			\
391 ({						\
392 	static struct lock_class_key __key;	\
393 	__class_register(class, &__key);	\
394 })
395 
396 struct class_compat;
397 struct class_compat *class_compat_register(const char *name);
398 void class_compat_unregister(struct class_compat *cls);
399 int class_compat_create_link(struct class_compat *cls, struct device *dev,
400 			     struct device *device_link);
401 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
402 			      struct device *device_link);
403 
404 extern void class_dev_iter_init(struct class_dev_iter *iter,
405 				struct class *class,
406 				struct device *start,
407 				const struct device_type *type);
408 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
409 extern void class_dev_iter_exit(struct class_dev_iter *iter);
410 
411 extern int class_for_each_device(struct class *class, struct device *start,
412 				 void *data,
413 				 int (*fn)(struct device *dev, void *data));
414 extern struct device *class_find_device(struct class *class,
415 					struct device *start, const void *data,
416 					int (*match)(struct device *, const void *));
417 
418 struct class_attribute {
419 	struct attribute attr;
420 	ssize_t (*show)(struct class *class, struct class_attribute *attr,
421 			char *buf);
422 	ssize_t (*store)(struct class *class, struct class_attribute *attr,
423 			const char *buf, size_t count);
424 };
425 
426 #define CLASS_ATTR(_name, _mode, _show, _store) \
427 	struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
428 #define CLASS_ATTR_RW(_name) \
429 	struct class_attribute class_attr_##_name = __ATTR_RW(_name)
430 #define CLASS_ATTR_RO(_name) \
431 	struct class_attribute class_attr_##_name = __ATTR_RO(_name)
432 
433 extern int __must_check class_create_file_ns(struct class *class,
434 					     const struct class_attribute *attr,
435 					     const void *ns);
436 extern void class_remove_file_ns(struct class *class,
437 				 const struct class_attribute *attr,
438 				 const void *ns);
439 
440 static inline int __must_check class_create_file(struct class *class,
441 					const struct class_attribute *attr)
442 {
443 	return class_create_file_ns(class, attr, NULL);
444 }
445 
446 static inline void class_remove_file(struct class *class,
447 				     const struct class_attribute *attr)
448 {
449 	return class_remove_file_ns(class, attr, NULL);
450 }
451 
452 /* Simple class attribute that is just a static string */
453 struct class_attribute_string {
454 	struct class_attribute attr;
455 	char *str;
456 };
457 
458 /* Currently read-only only */
459 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
460 	{ __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
461 #define CLASS_ATTR_STRING(_name, _mode, _str) \
462 	struct class_attribute_string class_attr_##_name = \
463 		_CLASS_ATTR_STRING(_name, _mode, _str)
464 
465 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
466                         char *buf);
467 
468 struct class_interface {
469 	struct list_head	node;
470 	struct class		*class;
471 
472 	int (*add_dev)		(struct device *, struct class_interface *);
473 	void (*remove_dev)	(struct device *, struct class_interface *);
474 };
475 
476 extern int __must_check class_interface_register(struct class_interface *);
477 extern void class_interface_unregister(struct class_interface *);
478 
479 extern struct class * __must_check __class_create(struct module *owner,
480 						  const char *name,
481 						  struct lock_class_key *key);
482 extern void class_destroy(struct class *cls);
483 
484 /* This is a #define to keep the compiler from merging different
485  * instances of the __key variable */
486 #define class_create(owner, name)		\
487 ({						\
488 	static struct lock_class_key __key;	\
489 	__class_create(owner, name, &__key);	\
490 })
491 
492 /*
493  * The type of device, "struct device" is embedded in. A class
494  * or bus can contain devices of different types
495  * like "partitions" and "disks", "mouse" and "event".
496  * This identifies the device type and carries type-specific
497  * information, equivalent to the kobj_type of a kobject.
498  * If "name" is specified, the uevent will contain it in
499  * the DEVTYPE variable.
500  */
501 struct device_type {
502 	const char *name;
503 	const struct attribute_group **groups;
504 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
505 	char *(*devnode)(struct device *dev, umode_t *mode,
506 			 kuid_t *uid, kgid_t *gid);
507 	void (*release)(struct device *dev);
508 
509 	const struct dev_pm_ops *pm;
510 };
511 
512 /* interface for exporting device attributes */
513 struct device_attribute {
514 	struct attribute	attr;
515 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
516 			char *buf);
517 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
518 			 const char *buf, size_t count);
519 };
520 
521 struct dev_ext_attribute {
522 	struct device_attribute attr;
523 	void *var;
524 };
525 
526 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
527 			  char *buf);
528 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
529 			   const char *buf, size_t count);
530 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
531 			char *buf);
532 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
533 			 const char *buf, size_t count);
534 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
535 			char *buf);
536 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
537 			 const char *buf, size_t count);
538 
539 #define DEVICE_ATTR(_name, _mode, _show, _store) \
540 	struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
541 #define DEVICE_ATTR_RW(_name) \
542 	struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
543 #define DEVICE_ATTR_RO(_name) \
544 	struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
545 #define DEVICE_ATTR_WO(_name) \
546 	struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
547 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
548 	struct dev_ext_attribute dev_attr_##_name = \
549 		{ __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
550 #define DEVICE_INT_ATTR(_name, _mode, _var) \
551 	struct dev_ext_attribute dev_attr_##_name = \
552 		{ __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
553 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
554 	struct dev_ext_attribute dev_attr_##_name = \
555 		{ __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
556 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
557 	struct device_attribute dev_attr_##_name =		\
558 		__ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
559 
560 extern int device_create_file(struct device *device,
561 			      const struct device_attribute *entry);
562 extern void device_remove_file(struct device *dev,
563 			       const struct device_attribute *attr);
564 extern bool device_remove_file_self(struct device *dev,
565 				    const struct device_attribute *attr);
566 extern int __must_check device_create_bin_file(struct device *dev,
567 					const struct bin_attribute *attr);
568 extern void device_remove_bin_file(struct device *dev,
569 				   const struct bin_attribute *attr);
570 
571 /* device resource management */
572 typedef void (*dr_release_t)(struct device *dev, void *res);
573 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
574 
575 #ifdef CONFIG_DEBUG_DEVRES
576 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
577 			     const char *name);
578 #define devres_alloc(release, size, gfp) \
579 	__devres_alloc(release, size, gfp, #release)
580 #else
581 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
582 #endif
583 extern void devres_for_each_res(struct device *dev, dr_release_t release,
584 				dr_match_t match, void *match_data,
585 				void (*fn)(struct device *, void *, void *),
586 				void *data);
587 extern void devres_free(void *res);
588 extern void devres_add(struct device *dev, void *res);
589 extern void *devres_find(struct device *dev, dr_release_t release,
590 			 dr_match_t match, void *match_data);
591 extern void *devres_get(struct device *dev, void *new_res,
592 			dr_match_t match, void *match_data);
593 extern void *devres_remove(struct device *dev, dr_release_t release,
594 			   dr_match_t match, void *match_data);
595 extern int devres_destroy(struct device *dev, dr_release_t release,
596 			  dr_match_t match, void *match_data);
597 extern int devres_release(struct device *dev, dr_release_t release,
598 			  dr_match_t match, void *match_data);
599 
600 /* devres group */
601 extern void * __must_check devres_open_group(struct device *dev, void *id,
602 					     gfp_t gfp);
603 extern void devres_close_group(struct device *dev, void *id);
604 extern void devres_remove_group(struct device *dev, void *id);
605 extern int devres_release_group(struct device *dev, void *id);
606 
607 /* managed devm_k.alloc/kfree for device drivers */
608 extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp);
609 extern char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt,
610 			     va_list ap);
611 extern __printf(3, 4)
612 char *devm_kasprintf(struct device *dev, gfp_t gfp, const char *fmt, ...);
613 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
614 {
615 	return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
616 }
617 static inline void *devm_kmalloc_array(struct device *dev,
618 				       size_t n, size_t size, gfp_t flags)
619 {
620 	if (size != 0 && n > SIZE_MAX / size)
621 		return NULL;
622 	return devm_kmalloc(dev, n * size, flags);
623 }
624 static inline void *devm_kcalloc(struct device *dev,
625 				 size_t n, size_t size, gfp_t flags)
626 {
627 	return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
628 }
629 extern void devm_kfree(struct device *dev, void *p);
630 extern char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp);
631 extern void *devm_kmemdup(struct device *dev, const void *src, size_t len,
632 			  gfp_t gfp);
633 
634 extern unsigned long devm_get_free_pages(struct device *dev,
635 					 gfp_t gfp_mask, unsigned int order);
636 extern void devm_free_pages(struct device *dev, unsigned long addr);
637 
638 void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
639 
640 /* allows to add/remove a custom action to devres stack */
641 int devm_add_action(struct device *dev, void (*action)(void *), void *data);
642 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
643 
644 struct device_dma_parameters {
645 	/*
646 	 * a low level driver may set these to teach IOMMU code about
647 	 * sg limitations.
648 	 */
649 	unsigned int max_segment_size;
650 	unsigned long segment_boundary_mask;
651 };
652 
653 struct acpi_device;
654 
655 struct acpi_dev_node {
656 #ifdef CONFIG_ACPI
657 	struct acpi_device *companion;
658 #endif
659 };
660 
661 /**
662  * struct device - The basic device structure
663  * @parent:	The device's "parent" device, the device to which it is attached.
664  * 		In most cases, a parent device is some sort of bus or host
665  * 		controller. If parent is NULL, the device, is a top-level device,
666  * 		which is not usually what you want.
667  * @p:		Holds the private data of the driver core portions of the device.
668  * 		See the comment of the struct device_private for detail.
669  * @kobj:	A top-level, abstract class from which other classes are derived.
670  * @init_name:	Initial name of the device.
671  * @type:	The type of device.
672  * 		This identifies the device type and carries type-specific
673  * 		information.
674  * @mutex:	Mutex to synchronize calls to its driver.
675  * @bus:	Type of bus device is on.
676  * @driver:	Which driver has allocated this
677  * @platform_data: Platform data specific to the device.
678  * 		Example: For devices on custom boards, as typical of embedded
679  * 		and SOC based hardware, Linux often uses platform_data to point
680  * 		to board-specific structures describing devices and how they
681  * 		are wired.  That can include what ports are available, chip
682  * 		variants, which GPIO pins act in what additional roles, and so
683  * 		on.  This shrinks the "Board Support Packages" (BSPs) and
684  * 		minimizes board-specific #ifdefs in drivers.
685  * @driver_data: Private pointer for driver specific info.
686  * @power:	For device power management.
687  * 		See Documentation/power/devices.txt for details.
688  * @pm_domain:	Provide callbacks that are executed during system suspend,
689  * 		hibernation, system resume and during runtime PM transitions
690  * 		along with subsystem-level and driver-level callbacks.
691  * @pins:	For device pin management.
692  *		See Documentation/pinctrl.txt for details.
693  * @numa_node:	NUMA node this device is close to.
694  * @dma_mask:	Dma mask (if dma'ble device).
695  * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
696  * 		hardware supports 64-bit addresses for consistent allocations
697  * 		such descriptors.
698  * @dma_pfn_offset: offset of DMA memory range relatively of RAM
699  * @dma_parms:	A low level driver may set these to teach IOMMU code about
700  * 		segment limitations.
701  * @dma_pools:	Dma pools (if dma'ble device).
702  * @dma_mem:	Internal for coherent mem override.
703  * @cma_area:	Contiguous memory area for dma allocations
704  * @archdata:	For arch-specific additions.
705  * @of_node:	Associated device tree node.
706  * @acpi_node:	Associated ACPI device node.
707  * @devt:	For creating the sysfs "dev".
708  * @id:		device instance
709  * @devres_lock: Spinlock to protect the resource of the device.
710  * @devres_head: The resources list of the device.
711  * @knode_class: The node used to add the device to the class list.
712  * @class:	The class of the device.
713  * @groups:	Optional attribute groups.
714  * @release:	Callback to free the device after all references have
715  * 		gone away. This should be set by the allocator of the
716  * 		device (i.e. the bus driver that discovered the device).
717  * @iommu_group: IOMMU group the device belongs to.
718  *
719  * @offline_disabled: If set, the device is permanently online.
720  * @offline:	Set after successful invocation of bus type's .offline().
721  *
722  * At the lowest level, every device in a Linux system is represented by an
723  * instance of struct device. The device structure contains the information
724  * that the device model core needs to model the system. Most subsystems,
725  * however, track additional information about the devices they host. As a
726  * result, it is rare for devices to be represented by bare device structures;
727  * instead, that structure, like kobject structures, is usually embedded within
728  * a higher-level representation of the device.
729  */
730 struct device {
731 	struct device		*parent;
732 
733 	struct device_private	*p;
734 
735 	struct kobject kobj;
736 	const char		*init_name; /* initial name of the device */
737 	const struct device_type *type;
738 
739 	struct mutex		mutex;	/* mutex to synchronize calls to
740 					 * its driver.
741 					 */
742 
743 	struct bus_type	*bus;		/* type of bus device is on */
744 	struct device_driver *driver;	/* which driver has allocated this
745 					   device */
746 	void		*platform_data;	/* Platform specific data, device
747 					   core doesn't touch it */
748 	void		*driver_data;	/* Driver data, set and get with
749 					   dev_set/get_drvdata */
750 	struct dev_pm_info	power;
751 	struct dev_pm_domain	*pm_domain;
752 
753 #ifdef CONFIG_PINCTRL
754 	struct dev_pin_info	*pins;
755 #endif
756 
757 #ifdef CONFIG_NUMA
758 	int		numa_node;	/* NUMA node this device is close to */
759 #endif
760 	u64		*dma_mask;	/* dma mask (if dma'able device) */
761 	u64		coherent_dma_mask;/* Like dma_mask, but for
762 					     alloc_coherent mappings as
763 					     not all hardware supports
764 					     64 bit addresses for consistent
765 					     allocations such descriptors. */
766 	unsigned long	dma_pfn_offset;
767 
768 	struct device_dma_parameters *dma_parms;
769 
770 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
771 
772 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
773 					     override */
774 #ifdef CONFIG_DMA_CMA
775 	struct cma *cma_area;		/* contiguous memory area for dma
776 					   allocations */
777 #endif
778 	/* arch specific additions */
779 	struct dev_archdata	archdata;
780 
781 	struct device_node	*of_node; /* associated device tree node */
782 	struct acpi_dev_node	acpi_node; /* associated ACPI device node */
783 
784 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
785 	u32			id;	/* device instance */
786 
787 	spinlock_t		devres_lock;
788 	struct list_head	devres_head;
789 
790 	struct klist_node	knode_class;
791 	struct class		*class;
792 	const struct attribute_group **groups;	/* optional groups */
793 
794 	void	(*release)(struct device *dev);
795 	struct iommu_group	*iommu_group;
796 
797 	bool			offline_disabled:1;
798 	bool			offline:1;
799 };
800 
801 static inline struct device *kobj_to_dev(struct kobject *kobj)
802 {
803 	return container_of(kobj, struct device, kobj);
804 }
805 
806 /* Get the wakeup routines, which depend on struct device */
807 #include <linux/pm_wakeup.h>
808 
809 static inline const char *dev_name(const struct device *dev)
810 {
811 	/* Use the init name until the kobject becomes available */
812 	if (dev->init_name)
813 		return dev->init_name;
814 
815 	return kobject_name(&dev->kobj);
816 }
817 
818 extern __printf(2, 3)
819 int dev_set_name(struct device *dev, const char *name, ...);
820 
821 #ifdef CONFIG_NUMA
822 static inline int dev_to_node(struct device *dev)
823 {
824 	return dev->numa_node;
825 }
826 static inline void set_dev_node(struct device *dev, int node)
827 {
828 	dev->numa_node = node;
829 }
830 #else
831 static inline int dev_to_node(struct device *dev)
832 {
833 	return -1;
834 }
835 static inline void set_dev_node(struct device *dev, int node)
836 {
837 }
838 #endif
839 
840 static inline void *dev_get_drvdata(const struct device *dev)
841 {
842 	return dev->driver_data;
843 }
844 
845 static inline void dev_set_drvdata(struct device *dev, void *data)
846 {
847 	dev->driver_data = data;
848 }
849 
850 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
851 {
852 	return dev ? dev->power.subsys_data : NULL;
853 }
854 
855 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
856 {
857 	return dev->kobj.uevent_suppress;
858 }
859 
860 static inline void dev_set_uevent_suppress(struct device *dev, int val)
861 {
862 	dev->kobj.uevent_suppress = val;
863 }
864 
865 static inline int device_is_registered(struct device *dev)
866 {
867 	return dev->kobj.state_in_sysfs;
868 }
869 
870 static inline void device_enable_async_suspend(struct device *dev)
871 {
872 	if (!dev->power.is_prepared)
873 		dev->power.async_suspend = true;
874 }
875 
876 static inline void device_disable_async_suspend(struct device *dev)
877 {
878 	if (!dev->power.is_prepared)
879 		dev->power.async_suspend = false;
880 }
881 
882 static inline bool device_async_suspend_enabled(struct device *dev)
883 {
884 	return !!dev->power.async_suspend;
885 }
886 
887 static inline void pm_suspend_ignore_children(struct device *dev, bool enable)
888 {
889 	dev->power.ignore_children = enable;
890 }
891 
892 static inline void dev_pm_syscore_device(struct device *dev, bool val)
893 {
894 #ifdef CONFIG_PM_SLEEP
895 	dev->power.syscore = val;
896 #endif
897 }
898 
899 static inline void device_lock(struct device *dev)
900 {
901 	mutex_lock(&dev->mutex);
902 }
903 
904 static inline int device_trylock(struct device *dev)
905 {
906 	return mutex_trylock(&dev->mutex);
907 }
908 
909 static inline void device_unlock(struct device *dev)
910 {
911 	mutex_unlock(&dev->mutex);
912 }
913 
914 static inline void device_lock_assert(struct device *dev)
915 {
916 	lockdep_assert_held(&dev->mutex);
917 }
918 
919 void driver_init(void);
920 
921 /*
922  * High level routines for use by the bus drivers
923  */
924 extern int __must_check device_register(struct device *dev);
925 extern void device_unregister(struct device *dev);
926 extern void device_initialize(struct device *dev);
927 extern int __must_check device_add(struct device *dev);
928 extern void device_del(struct device *dev);
929 extern int device_for_each_child(struct device *dev, void *data,
930 		     int (*fn)(struct device *dev, void *data));
931 extern struct device *device_find_child(struct device *dev, void *data,
932 				int (*match)(struct device *dev, void *data));
933 extern int device_rename(struct device *dev, const char *new_name);
934 extern int device_move(struct device *dev, struct device *new_parent,
935 		       enum dpm_order dpm_order);
936 extern const char *device_get_devnode(struct device *dev,
937 				      umode_t *mode, kuid_t *uid, kgid_t *gid,
938 				      const char **tmp);
939 
940 static inline bool device_supports_offline(struct device *dev)
941 {
942 	return dev->bus && dev->bus->offline && dev->bus->online;
943 }
944 
945 extern void lock_device_hotplug(void);
946 extern void unlock_device_hotplug(void);
947 extern int lock_device_hotplug_sysfs(void);
948 extern int device_offline(struct device *dev);
949 extern int device_online(struct device *dev);
950 /*
951  * Root device objects for grouping under /sys/devices
952  */
953 extern struct device *__root_device_register(const char *name,
954 					     struct module *owner);
955 
956 /* This is a macro to avoid include problems with THIS_MODULE */
957 #define root_device_register(name) \
958 	__root_device_register(name, THIS_MODULE)
959 
960 extern void root_device_unregister(struct device *root);
961 
962 static inline void *dev_get_platdata(const struct device *dev)
963 {
964 	return dev->platform_data;
965 }
966 
967 /*
968  * Manual binding of a device to driver. See drivers/base/bus.c
969  * for information on use.
970  */
971 extern int __must_check device_bind_driver(struct device *dev);
972 extern void device_release_driver(struct device *dev);
973 extern int  __must_check device_attach(struct device *dev);
974 extern int __must_check driver_attach(struct device_driver *drv);
975 extern int __must_check device_reprobe(struct device *dev);
976 
977 /*
978  * Easy functions for dynamically creating devices on the fly
979  */
980 extern struct device *device_create_vargs(struct class *cls,
981 					  struct device *parent,
982 					  dev_t devt,
983 					  void *drvdata,
984 					  const char *fmt,
985 					  va_list vargs);
986 extern __printf(5, 6)
987 struct device *device_create(struct class *cls, struct device *parent,
988 			     dev_t devt, void *drvdata,
989 			     const char *fmt, ...);
990 extern __printf(6, 7)
991 struct device *device_create_with_groups(struct class *cls,
992 			     struct device *parent, dev_t devt, void *drvdata,
993 			     const struct attribute_group **groups,
994 			     const char *fmt, ...);
995 extern void device_destroy(struct class *cls, dev_t devt);
996 
997 /*
998  * Platform "fixup" functions - allow the platform to have their say
999  * about devices and actions that the general device layer doesn't
1000  * know about.
1001  */
1002 /* Notify platform of device discovery */
1003 extern int (*platform_notify)(struct device *dev);
1004 
1005 extern int (*platform_notify_remove)(struct device *dev);
1006 
1007 
1008 /*
1009  * get_device - atomically increment the reference count for the device.
1010  *
1011  */
1012 extern struct device *get_device(struct device *dev);
1013 extern void put_device(struct device *dev);
1014 
1015 #ifdef CONFIG_DEVTMPFS
1016 extern int devtmpfs_create_node(struct device *dev);
1017 extern int devtmpfs_delete_node(struct device *dev);
1018 extern int devtmpfs_mount(const char *mntdir);
1019 #else
1020 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
1021 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
1022 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
1023 #endif
1024 
1025 /* drivers/base/power/shutdown.c */
1026 extern void device_shutdown(void);
1027 
1028 /* debugging and troubleshooting/diagnostic helpers. */
1029 extern const char *dev_driver_string(const struct device *dev);
1030 
1031 
1032 #ifdef CONFIG_PRINTK
1033 
1034 extern __printf(3, 0)
1035 int dev_vprintk_emit(int level, const struct device *dev,
1036 		     const char *fmt, va_list args);
1037 extern __printf(3, 4)
1038 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...);
1039 
1040 extern __printf(3, 4)
1041 void dev_printk(const char *level, const struct device *dev,
1042 		const char *fmt, ...);
1043 extern __printf(2, 3)
1044 void dev_emerg(const struct device *dev, const char *fmt, ...);
1045 extern __printf(2, 3)
1046 void dev_alert(const struct device *dev, const char *fmt, ...);
1047 extern __printf(2, 3)
1048 void dev_crit(const struct device *dev, const char *fmt, ...);
1049 extern __printf(2, 3)
1050 void dev_err(const struct device *dev, const char *fmt, ...);
1051 extern __printf(2, 3)
1052 void dev_warn(const struct device *dev, const char *fmt, ...);
1053 extern __printf(2, 3)
1054 void dev_notice(const struct device *dev, const char *fmt, ...);
1055 extern __printf(2, 3)
1056 void _dev_info(const struct device *dev, const char *fmt, ...);
1057 
1058 #else
1059 
1060 static inline __printf(3, 0)
1061 int dev_vprintk_emit(int level, const struct device *dev,
1062 		     const char *fmt, va_list args)
1063 { return 0; }
1064 static inline __printf(3, 4)
1065 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
1066 { return 0; }
1067 
1068 static inline void __dev_printk(const char *level, const struct device *dev,
1069 				struct va_format *vaf)
1070 {}
1071 static inline __printf(3, 4)
1072 void dev_printk(const char *level, const struct device *dev,
1073 		const char *fmt, ...)
1074 {}
1075 
1076 static inline __printf(2, 3)
1077 void dev_emerg(const struct device *dev, const char *fmt, ...)
1078 {}
1079 static inline __printf(2, 3)
1080 void dev_crit(const struct device *dev, const char *fmt, ...)
1081 {}
1082 static inline __printf(2, 3)
1083 void dev_alert(const struct device *dev, const char *fmt, ...)
1084 {}
1085 static inline __printf(2, 3)
1086 void dev_err(const struct device *dev, const char *fmt, ...)
1087 {}
1088 static inline __printf(2, 3)
1089 void dev_warn(const struct device *dev, const char *fmt, ...)
1090 {}
1091 static inline __printf(2, 3)
1092 void dev_notice(const struct device *dev, const char *fmt, ...)
1093 {}
1094 static inline __printf(2, 3)
1095 void _dev_info(const struct device *dev, const char *fmt, ...)
1096 {}
1097 
1098 #endif
1099 
1100 /*
1101  * Stupid hackaround for existing uses of non-printk uses dev_info
1102  *
1103  * Note that the definition of dev_info below is actually _dev_info
1104  * and a macro is used to avoid redefining dev_info
1105  */
1106 
1107 #define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)
1108 
1109 #if defined(CONFIG_DYNAMIC_DEBUG)
1110 #define dev_dbg(dev, format, ...)		     \
1111 do {						     \
1112 	dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
1113 } while (0)
1114 #elif defined(DEBUG)
1115 #define dev_dbg(dev, format, arg...)		\
1116 	dev_printk(KERN_DEBUG, dev, format, ##arg)
1117 #else
1118 #define dev_dbg(dev, format, arg...)				\
1119 ({								\
1120 	if (0)							\
1121 		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
1122 })
1123 #endif
1124 
1125 #ifdef CONFIG_PRINTK
1126 #define dev_level_once(dev_level, dev, fmt, ...)			\
1127 do {									\
1128 	static bool __print_once __read_mostly;				\
1129 									\
1130 	if (!__print_once) {						\
1131 		__print_once = true;					\
1132 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1133 	}								\
1134 } while (0)
1135 #else
1136 #define dev_level_once(dev_level, dev, fmt, ...)			\
1137 do {									\
1138 	if (0)								\
1139 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1140 } while (0)
1141 #endif
1142 
1143 #define dev_emerg_once(dev, fmt, ...)					\
1144 	dev_level_once(dev_emerg, dev, fmt, ##__VA_ARGS__)
1145 #define dev_alert_once(dev, fmt, ...)					\
1146 	dev_level_once(dev_alert, dev, fmt, ##__VA_ARGS__)
1147 #define dev_crit_once(dev, fmt, ...)					\
1148 	dev_level_once(dev_crit, dev, fmt, ##__VA_ARGS__)
1149 #define dev_err_once(dev, fmt, ...)					\
1150 	dev_level_once(dev_err, dev, fmt, ##__VA_ARGS__)
1151 #define dev_warn_once(dev, fmt, ...)					\
1152 	dev_level_once(dev_warn, dev, fmt, ##__VA_ARGS__)
1153 #define dev_notice_once(dev, fmt, ...)					\
1154 	dev_level_once(dev_notice, dev, fmt, ##__VA_ARGS__)
1155 #define dev_info_once(dev, fmt, ...)					\
1156 	dev_level_once(dev_info, dev, fmt, ##__VA_ARGS__)
1157 #define dev_dbg_once(dev, fmt, ...)					\
1158 	dev_level_once(dev_dbg, dev, fmt, ##__VA_ARGS__)
1159 
1160 #define dev_level_ratelimited(dev_level, dev, fmt, ...)			\
1161 do {									\
1162 	static DEFINE_RATELIMIT_STATE(_rs,				\
1163 				      DEFAULT_RATELIMIT_INTERVAL,	\
1164 				      DEFAULT_RATELIMIT_BURST);		\
1165 	if (__ratelimit(&_rs))						\
1166 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1167 } while (0)
1168 
1169 #define dev_emerg_ratelimited(dev, fmt, ...)				\
1170 	dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__)
1171 #define dev_alert_ratelimited(dev, fmt, ...)				\
1172 	dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__)
1173 #define dev_crit_ratelimited(dev, fmt, ...)				\
1174 	dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__)
1175 #define dev_err_ratelimited(dev, fmt, ...)				\
1176 	dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__)
1177 #define dev_warn_ratelimited(dev, fmt, ...)				\
1178 	dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__)
1179 #define dev_notice_ratelimited(dev, fmt, ...)				\
1180 	dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__)
1181 #define dev_info_ratelimited(dev, fmt, ...)				\
1182 	dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__)
1183 #if defined(CONFIG_DYNAMIC_DEBUG)
1184 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
1185 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1186 do {									\
1187 	static DEFINE_RATELIMIT_STATE(_rs,				\
1188 				      DEFAULT_RATELIMIT_INTERVAL,	\
1189 				      DEFAULT_RATELIMIT_BURST);		\
1190 	DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);			\
1191 	if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) &&	\
1192 	    __ratelimit(&_rs))						\
1193 		__dynamic_dev_dbg(&descriptor, dev, fmt,		\
1194 				  ##__VA_ARGS__);			\
1195 } while (0)
1196 #elif defined(DEBUG)
1197 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1198 do {									\
1199 	static DEFINE_RATELIMIT_STATE(_rs,				\
1200 				      DEFAULT_RATELIMIT_INTERVAL,	\
1201 				      DEFAULT_RATELIMIT_BURST);		\
1202 	if (__ratelimit(&_rs))						\
1203 		dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__);	\
1204 } while (0)
1205 #else
1206 #define dev_dbg_ratelimited(dev, fmt, ...)			\
1207 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
1208 #endif
1209 
1210 #ifdef VERBOSE_DEBUG
1211 #define dev_vdbg	dev_dbg
1212 #else
1213 #define dev_vdbg(dev, format, arg...)				\
1214 ({								\
1215 	if (0)							\
1216 		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
1217 })
1218 #endif
1219 
1220 /*
1221  * dev_WARN*() acts like dev_printk(), but with the key difference of
1222  * using WARN/WARN_ONCE to include file/line information and a backtrace.
1223  */
1224 #define dev_WARN(dev, format, arg...) \
1225 	WARN(1, "%s %s: " format, dev_driver_string(dev), dev_name(dev), ## arg);
1226 
1227 #define dev_WARN_ONCE(dev, condition, format, arg...) \
1228 	WARN_ONCE(condition, "%s %s: " format, \
1229 			dev_driver_string(dev), dev_name(dev), ## arg)
1230 
1231 /* Create alias, so I can be autoloaded. */
1232 #define MODULE_ALIAS_CHARDEV(major,minor) \
1233 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1234 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1235 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
1236 
1237 #ifdef CONFIG_SYSFS_DEPRECATED
1238 extern long sysfs_deprecated;
1239 #else
1240 #define sysfs_deprecated 0
1241 #endif
1242 
1243 /**
1244  * module_driver() - Helper macro for drivers that don't do anything
1245  * special in module init/exit. This eliminates a lot of boilerplate.
1246  * Each module may only use this macro once, and calling it replaces
1247  * module_init() and module_exit().
1248  *
1249  * @__driver: driver name
1250  * @__register: register function for this driver type
1251  * @__unregister: unregister function for this driver type
1252  * @...: Additional arguments to be passed to __register and __unregister.
1253  *
1254  * Use this macro to construct bus specific macros for registering
1255  * drivers, and do not use it on its own.
1256  */
1257 #define module_driver(__driver, __register, __unregister, ...) \
1258 static int __init __driver##_init(void) \
1259 { \
1260 	return __register(&(__driver) , ##__VA_ARGS__); \
1261 } \
1262 module_init(__driver##_init); \
1263 static void __exit __driver##_exit(void) \
1264 { \
1265 	__unregister(&(__driver) , ##__VA_ARGS__); \
1266 } \
1267 module_exit(__driver##_exit);
1268 
1269 #endif /* _DEVICE_H_ */
1270