xref: /linux-6.15/include/linux/device.h (revision 5d4a2e29)
1 /*
2  * device.h - generic, centralized driver model
3  *
4  * Copyright (c) 2001-2003 Patrick Mochel <[email protected]>
5  * Copyright (c) 2004-2009 Greg Kroah-Hartman <[email protected]>
6  * Copyright (c) 2008-2009 Novell Inc.
7  *
8  * This file is released under the GPLv2
9  *
10  * See Documentation/driver-model/ for more information.
11  */
12 
13 #ifndef _DEVICE_H_
14 #define _DEVICE_H_
15 
16 #include <linux/ioport.h>
17 #include <linux/kobject.h>
18 #include <linux/klist.h>
19 #include <linux/list.h>
20 #include <linux/lockdep.h>
21 #include <linux/compiler.h>
22 #include <linux/types.h>
23 #include <linux/module.h>
24 #include <linux/pm.h>
25 #include <asm/atomic.h>
26 #include <asm/device.h>
27 
28 struct device;
29 struct device_private;
30 struct device_driver;
31 struct driver_private;
32 struct class;
33 struct class_private;
34 struct bus_type;
35 struct bus_type_private;
36 struct device_node;
37 
38 struct bus_attribute {
39 	struct attribute	attr;
40 	ssize_t (*show)(struct bus_type *bus, char *buf);
41 	ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
42 };
43 
44 #define BUS_ATTR(_name, _mode, _show, _store)	\
45 struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)
46 
47 extern int __must_check bus_create_file(struct bus_type *,
48 					struct bus_attribute *);
49 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
50 
51 struct bus_type {
52 	const char		*name;
53 	struct bus_attribute	*bus_attrs;
54 	struct device_attribute	*dev_attrs;
55 	struct driver_attribute	*drv_attrs;
56 
57 	int (*match)(struct device *dev, struct device_driver *drv);
58 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
59 	int (*probe)(struct device *dev);
60 	int (*remove)(struct device *dev);
61 	void (*shutdown)(struct device *dev);
62 
63 	int (*suspend)(struct device *dev, pm_message_t state);
64 	int (*resume)(struct device *dev);
65 
66 	const struct dev_pm_ops *pm;
67 
68 	struct bus_type_private *p;
69 };
70 
71 extern int __must_check bus_register(struct bus_type *bus);
72 extern void bus_unregister(struct bus_type *bus);
73 
74 extern int __must_check bus_rescan_devices(struct bus_type *bus);
75 
76 /* iterator helpers for buses */
77 
78 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
79 		     int (*fn)(struct device *dev, void *data));
80 struct device *bus_find_device(struct bus_type *bus, struct device *start,
81 			       void *data,
82 			       int (*match)(struct device *dev, void *data));
83 struct device *bus_find_device_by_name(struct bus_type *bus,
84 				       struct device *start,
85 				       const char *name);
86 
87 int __must_check bus_for_each_drv(struct bus_type *bus,
88 				  struct device_driver *start, void *data,
89 				  int (*fn)(struct device_driver *, void *));
90 
91 void bus_sort_breadthfirst(struct bus_type *bus,
92 			   int (*compare)(const struct device *a,
93 					  const struct device *b));
94 /*
95  * Bus notifiers: Get notified of addition/removal of devices
96  * and binding/unbinding of drivers to devices.
97  * In the long run, it should be a replacement for the platform
98  * notify hooks.
99  */
100 struct notifier_block;
101 
102 extern int bus_register_notifier(struct bus_type *bus,
103 				 struct notifier_block *nb);
104 extern int bus_unregister_notifier(struct bus_type *bus,
105 				   struct notifier_block *nb);
106 
107 /* All 4 notifers below get called with the target struct device *
108  * as an argument. Note that those functions are likely to be called
109  * with the device lock held in the core, so be careful.
110  */
111 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
112 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device removed */
113 #define BUS_NOTIFY_BOUND_DRIVER		0x00000003 /* driver bound to device */
114 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000004 /* driver about to be
115 						      unbound */
116 #define BUS_NOTIFY_UNBOUND_DRIVER	0x00000005 /* driver is unbound
117 						      from the device */
118 
119 extern struct kset *bus_get_kset(struct bus_type *bus);
120 extern struct klist *bus_get_device_klist(struct bus_type *bus);
121 
122 struct device_driver {
123 	const char		*name;
124 	struct bus_type		*bus;
125 
126 	struct module		*owner;
127 	const char		*mod_name;	/* used for built-in modules */
128 
129 	bool suppress_bind_attrs;	/* disables bind/unbind via sysfs */
130 
131 #if defined(CONFIG_OF)
132 	const struct of_device_id	*of_match_table;
133 #endif
134 
135 	int (*probe) (struct device *dev);
136 	int (*remove) (struct device *dev);
137 	void (*shutdown) (struct device *dev);
138 	int (*suspend) (struct device *dev, pm_message_t state);
139 	int (*resume) (struct device *dev);
140 	const struct attribute_group **groups;
141 
142 	const struct dev_pm_ops *pm;
143 
144 	struct driver_private *p;
145 };
146 
147 
148 extern int __must_check driver_register(struct device_driver *drv);
149 extern void driver_unregister(struct device_driver *drv);
150 
151 extern struct device_driver *get_driver(struct device_driver *drv);
152 extern void put_driver(struct device_driver *drv);
153 extern struct device_driver *driver_find(const char *name,
154 					 struct bus_type *bus);
155 extern int driver_probe_done(void);
156 extern void wait_for_device_probe(void);
157 
158 
159 /* sysfs interface for exporting driver attributes */
160 
161 struct driver_attribute {
162 	struct attribute attr;
163 	ssize_t (*show)(struct device_driver *driver, char *buf);
164 	ssize_t (*store)(struct device_driver *driver, const char *buf,
165 			 size_t count);
166 };
167 
168 #define DRIVER_ATTR(_name, _mode, _show, _store)	\
169 struct driver_attribute driver_attr_##_name =		\
170 	__ATTR(_name, _mode, _show, _store)
171 
172 extern int __must_check driver_create_file(struct device_driver *driver,
173 					const struct driver_attribute *attr);
174 extern void driver_remove_file(struct device_driver *driver,
175 			       const struct driver_attribute *attr);
176 
177 extern int __must_check driver_add_kobj(struct device_driver *drv,
178 					struct kobject *kobj,
179 					const char *fmt, ...);
180 
181 extern int __must_check driver_for_each_device(struct device_driver *drv,
182 					       struct device *start,
183 					       void *data,
184 					       int (*fn)(struct device *dev,
185 							 void *));
186 struct device *driver_find_device(struct device_driver *drv,
187 				  struct device *start, void *data,
188 				  int (*match)(struct device *dev, void *data));
189 
190 /*
191  * device classes
192  */
193 struct class {
194 	const char		*name;
195 	struct module		*owner;
196 
197 	struct class_attribute		*class_attrs;
198 	struct device_attribute		*dev_attrs;
199 	struct kobject			*dev_kobj;
200 
201 	int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
202 	char *(*devnode)(struct device *dev, mode_t *mode);
203 
204 	void (*class_release)(struct class *class);
205 	void (*dev_release)(struct device *dev);
206 
207 	int (*suspend)(struct device *dev, pm_message_t state);
208 	int (*resume)(struct device *dev);
209 
210 	const struct kobj_ns_type_operations *ns_type;
211 	const void *(*namespace)(struct device *dev);
212 
213 	const struct dev_pm_ops *pm;
214 
215 	struct class_private *p;
216 };
217 
218 struct class_dev_iter {
219 	struct klist_iter		ki;
220 	const struct device_type	*type;
221 };
222 
223 extern struct kobject *sysfs_dev_block_kobj;
224 extern struct kobject *sysfs_dev_char_kobj;
225 extern int __must_check __class_register(struct class *class,
226 					 struct lock_class_key *key);
227 extern void class_unregister(struct class *class);
228 
229 /* This is a #define to keep the compiler from merging different
230  * instances of the __key variable */
231 #define class_register(class)			\
232 ({						\
233 	static struct lock_class_key __key;	\
234 	__class_register(class, &__key);	\
235 })
236 
237 struct class_compat;
238 struct class_compat *class_compat_register(const char *name);
239 void class_compat_unregister(struct class_compat *cls);
240 int class_compat_create_link(struct class_compat *cls, struct device *dev,
241 			     struct device *device_link);
242 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
243 			      struct device *device_link);
244 
245 extern void class_dev_iter_init(struct class_dev_iter *iter,
246 				struct class *class,
247 				struct device *start,
248 				const struct device_type *type);
249 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
250 extern void class_dev_iter_exit(struct class_dev_iter *iter);
251 
252 extern int class_for_each_device(struct class *class, struct device *start,
253 				 void *data,
254 				 int (*fn)(struct device *dev, void *data));
255 extern struct device *class_find_device(struct class *class,
256 					struct device *start, void *data,
257 					int (*match)(struct device *, void *));
258 
259 struct class_attribute {
260 	struct attribute attr;
261 	ssize_t (*show)(struct class *class, struct class_attribute *attr,
262 			char *buf);
263 	ssize_t (*store)(struct class *class, struct class_attribute *attr,
264 			const char *buf, size_t count);
265 };
266 
267 #define CLASS_ATTR(_name, _mode, _show, _store)			\
268 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
269 
270 extern int __must_check class_create_file(struct class *class,
271 					  const struct class_attribute *attr);
272 extern void class_remove_file(struct class *class,
273 			      const struct class_attribute *attr);
274 
275 /* Simple class attribute that is just a static string */
276 
277 struct class_attribute_string {
278 	struct class_attribute attr;
279 	char *str;
280 };
281 
282 /* Currently read-only only */
283 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
284 	{ __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
285 #define CLASS_ATTR_STRING(_name, _mode, _str) \
286 	struct class_attribute_string class_attr_##_name = \
287 		_CLASS_ATTR_STRING(_name, _mode, _str)
288 
289 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
290                         char *buf);
291 
292 struct class_interface {
293 	struct list_head	node;
294 	struct class		*class;
295 
296 	int (*add_dev)		(struct device *, struct class_interface *);
297 	void (*remove_dev)	(struct device *, struct class_interface *);
298 };
299 
300 extern int __must_check class_interface_register(struct class_interface *);
301 extern void class_interface_unregister(struct class_interface *);
302 
303 extern struct class * __must_check __class_create(struct module *owner,
304 						  const char *name,
305 						  struct lock_class_key *key);
306 extern void class_destroy(struct class *cls);
307 
308 /* This is a #define to keep the compiler from merging different
309  * instances of the __key variable */
310 #define class_create(owner, name)		\
311 ({						\
312 	static struct lock_class_key __key;	\
313 	__class_create(owner, name, &__key);	\
314 })
315 
316 /*
317  * The type of device, "struct device" is embedded in. A class
318  * or bus can contain devices of different types
319  * like "partitions" and "disks", "mouse" and "event".
320  * This identifies the device type and carries type-specific
321  * information, equivalent to the kobj_type of a kobject.
322  * If "name" is specified, the uevent will contain it in
323  * the DEVTYPE variable.
324  */
325 struct device_type {
326 	const char *name;
327 	const struct attribute_group **groups;
328 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
329 	char *(*devnode)(struct device *dev, mode_t *mode);
330 	void (*release)(struct device *dev);
331 
332 	const struct dev_pm_ops *pm;
333 };
334 
335 /* interface for exporting device attributes */
336 struct device_attribute {
337 	struct attribute	attr;
338 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
339 			char *buf);
340 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
341 			 const char *buf, size_t count);
342 };
343 
344 #define DEVICE_ATTR(_name, _mode, _show, _store) \
345 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
346 
347 extern int __must_check device_create_file(struct device *device,
348 					const struct device_attribute *entry);
349 extern void device_remove_file(struct device *dev,
350 			       const struct device_attribute *attr);
351 extern int __must_check device_create_bin_file(struct device *dev,
352 					const struct bin_attribute *attr);
353 extern void device_remove_bin_file(struct device *dev,
354 				   const struct bin_attribute *attr);
355 extern int device_schedule_callback_owner(struct device *dev,
356 		void (*func)(struct device *dev), struct module *owner);
357 
358 /* This is a macro to avoid include problems with THIS_MODULE */
359 #define device_schedule_callback(dev, func)			\
360 	device_schedule_callback_owner(dev, func, THIS_MODULE)
361 
362 /* device resource management */
363 typedef void (*dr_release_t)(struct device *dev, void *res);
364 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
365 
366 #ifdef CONFIG_DEBUG_DEVRES
367 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
368 			     const char *name);
369 #define devres_alloc(release, size, gfp) \
370 	__devres_alloc(release, size, gfp, #release)
371 #else
372 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
373 #endif
374 extern void devres_free(void *res);
375 extern void devres_add(struct device *dev, void *res);
376 extern void *devres_find(struct device *dev, dr_release_t release,
377 			 dr_match_t match, void *match_data);
378 extern void *devres_get(struct device *dev, void *new_res,
379 			dr_match_t match, void *match_data);
380 extern void *devres_remove(struct device *dev, dr_release_t release,
381 			   dr_match_t match, void *match_data);
382 extern int devres_destroy(struct device *dev, dr_release_t release,
383 			  dr_match_t match, void *match_data);
384 
385 /* devres group */
386 extern void * __must_check devres_open_group(struct device *dev, void *id,
387 					     gfp_t gfp);
388 extern void devres_close_group(struct device *dev, void *id);
389 extern void devres_remove_group(struct device *dev, void *id);
390 extern int devres_release_group(struct device *dev, void *id);
391 
392 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
393 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
394 extern void devm_kfree(struct device *dev, void *p);
395 
396 struct device_dma_parameters {
397 	/*
398 	 * a low level driver may set these to teach IOMMU code about
399 	 * sg limitations.
400 	 */
401 	unsigned int max_segment_size;
402 	unsigned long segment_boundary_mask;
403 };
404 
405 struct device {
406 	struct device		*parent;
407 
408 	struct device_private	*p;
409 
410 	struct kobject kobj;
411 	const char		*init_name; /* initial name of the device */
412 	struct device_type	*type;
413 
414 	struct mutex		mutex;	/* mutex to synchronize calls to
415 					 * its driver.
416 					 */
417 
418 	struct bus_type	*bus;		/* type of bus device is on */
419 	struct device_driver *driver;	/* which driver has allocated this
420 					   device */
421 	void		*platform_data;	/* Platform specific data, device
422 					   core doesn't touch it */
423 	struct dev_pm_info	power;
424 
425 #ifdef CONFIG_NUMA
426 	int		numa_node;	/* NUMA node this device is close to */
427 #endif
428 	u64		*dma_mask;	/* dma mask (if dma'able device) */
429 	u64		coherent_dma_mask;/* Like dma_mask, but for
430 					     alloc_coherent mappings as
431 					     not all hardware supports
432 					     64 bit addresses for consistent
433 					     allocations such descriptors. */
434 
435 	struct device_dma_parameters *dma_parms;
436 
437 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
438 
439 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
440 					     override */
441 	/* arch specific additions */
442 	struct dev_archdata	archdata;
443 #ifdef CONFIG_OF
444 	struct device_node	*of_node;
445 #endif
446 
447 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
448 
449 	spinlock_t		devres_lock;
450 	struct list_head	devres_head;
451 
452 	struct klist_node	knode_class;
453 	struct class		*class;
454 	const struct attribute_group **groups;	/* optional groups */
455 
456 	void	(*release)(struct device *dev);
457 };
458 
459 /* Get the wakeup routines, which depend on struct device */
460 #include <linux/pm_wakeup.h>
461 
462 static inline const char *dev_name(const struct device *dev)
463 {
464 	/* Use the init name until the kobject becomes available */
465 	if (dev->init_name)
466 		return dev->init_name;
467 
468 	return kobject_name(&dev->kobj);
469 }
470 
471 extern int dev_set_name(struct device *dev, const char *name, ...)
472 			__attribute__((format(printf, 2, 3)));
473 
474 #ifdef CONFIG_NUMA
475 static inline int dev_to_node(struct device *dev)
476 {
477 	return dev->numa_node;
478 }
479 static inline void set_dev_node(struct device *dev, int node)
480 {
481 	dev->numa_node = node;
482 }
483 #else
484 static inline int dev_to_node(struct device *dev)
485 {
486 	return -1;
487 }
488 static inline void set_dev_node(struct device *dev, int node)
489 {
490 }
491 #endif
492 
493 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
494 {
495 	return dev->kobj.uevent_suppress;
496 }
497 
498 static inline void dev_set_uevent_suppress(struct device *dev, int val)
499 {
500 	dev->kobj.uevent_suppress = val;
501 }
502 
503 static inline int device_is_registered(struct device *dev)
504 {
505 	return dev->kobj.state_in_sysfs;
506 }
507 
508 static inline void device_enable_async_suspend(struct device *dev)
509 {
510 	if (dev->power.status == DPM_ON)
511 		dev->power.async_suspend = true;
512 }
513 
514 static inline void device_disable_async_suspend(struct device *dev)
515 {
516 	if (dev->power.status == DPM_ON)
517 		dev->power.async_suspend = false;
518 }
519 
520 static inline bool device_async_suspend_enabled(struct device *dev)
521 {
522 	return !!dev->power.async_suspend;
523 }
524 
525 static inline void device_lock(struct device *dev)
526 {
527 	mutex_lock(&dev->mutex);
528 }
529 
530 static inline int device_trylock(struct device *dev)
531 {
532 	return mutex_trylock(&dev->mutex);
533 }
534 
535 static inline void device_unlock(struct device *dev)
536 {
537 	mutex_unlock(&dev->mutex);
538 }
539 
540 void driver_init(void);
541 
542 /*
543  * High level routines for use by the bus drivers
544  */
545 extern int __must_check device_register(struct device *dev);
546 extern void device_unregister(struct device *dev);
547 extern void device_initialize(struct device *dev);
548 extern int __must_check device_add(struct device *dev);
549 extern void device_del(struct device *dev);
550 extern int device_for_each_child(struct device *dev, void *data,
551 		     int (*fn)(struct device *dev, void *data));
552 extern struct device *device_find_child(struct device *dev, void *data,
553 				int (*match)(struct device *dev, void *data));
554 extern int device_rename(struct device *dev, char *new_name);
555 extern int device_move(struct device *dev, struct device *new_parent,
556 		       enum dpm_order dpm_order);
557 extern const char *device_get_devnode(struct device *dev,
558 				      mode_t *mode, const char **tmp);
559 extern void *dev_get_drvdata(const struct device *dev);
560 extern void dev_set_drvdata(struct device *dev, void *data);
561 
562 /*
563  * Root device objects for grouping under /sys/devices
564  */
565 extern struct device *__root_device_register(const char *name,
566 					     struct module *owner);
567 static inline struct device *root_device_register(const char *name)
568 {
569 	return __root_device_register(name, THIS_MODULE);
570 }
571 extern void root_device_unregister(struct device *root);
572 
573 static inline void *dev_get_platdata(const struct device *dev)
574 {
575 	return dev->platform_data;
576 }
577 
578 /*
579  * Manual binding of a device to driver. See drivers/base/bus.c
580  * for information on use.
581  */
582 extern int __must_check device_bind_driver(struct device *dev);
583 extern void device_release_driver(struct device *dev);
584 extern int  __must_check device_attach(struct device *dev);
585 extern int __must_check driver_attach(struct device_driver *drv);
586 extern int __must_check device_reprobe(struct device *dev);
587 
588 /*
589  * Easy functions for dynamically creating devices on the fly
590  */
591 extern struct device *device_create_vargs(struct class *cls,
592 					  struct device *parent,
593 					  dev_t devt,
594 					  void *drvdata,
595 					  const char *fmt,
596 					  va_list vargs);
597 extern struct device *device_create(struct class *cls, struct device *parent,
598 				    dev_t devt, void *drvdata,
599 				    const char *fmt, ...)
600 				    __attribute__((format(printf, 5, 6)));
601 extern void device_destroy(struct class *cls, dev_t devt);
602 
603 /*
604  * Platform "fixup" functions - allow the platform to have their say
605  * about devices and actions that the general device layer doesn't
606  * know about.
607  */
608 /* Notify platform of device discovery */
609 extern int (*platform_notify)(struct device *dev);
610 
611 extern int (*platform_notify_remove)(struct device *dev);
612 
613 
614 /**
615  * get_device - atomically increment the reference count for the device.
616  *
617  */
618 extern struct device *get_device(struct device *dev);
619 extern void put_device(struct device *dev);
620 
621 extern void wait_for_device_probe(void);
622 
623 #ifdef CONFIG_DEVTMPFS
624 extern int devtmpfs_create_node(struct device *dev);
625 extern int devtmpfs_delete_node(struct device *dev);
626 extern int devtmpfs_mount(const char *mntdir);
627 #else
628 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
629 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
630 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
631 #endif
632 
633 /* drivers/base/power/shutdown.c */
634 extern void device_shutdown(void);
635 
636 /* drivers/base/sys.c */
637 extern void sysdev_shutdown(void);
638 
639 /* debugging and troubleshooting/diagnostic helpers. */
640 extern const char *dev_driver_string(const struct device *dev);
641 #define dev_printk(level, dev, format, arg...)	\
642 	printk(level "%s %s: " format , dev_driver_string(dev) , \
643 	       dev_name(dev) , ## arg)
644 
645 #define dev_emerg(dev, format, arg...)		\
646 	dev_printk(KERN_EMERG , dev , format , ## arg)
647 #define dev_alert(dev, format, arg...)		\
648 	dev_printk(KERN_ALERT , dev , format , ## arg)
649 #define dev_crit(dev, format, arg...)		\
650 	dev_printk(KERN_CRIT , dev , format , ## arg)
651 #define dev_err(dev, format, arg...)		\
652 	dev_printk(KERN_ERR , dev , format , ## arg)
653 #define dev_warn(dev, format, arg...)		\
654 	dev_printk(KERN_WARNING , dev , format , ## arg)
655 #define dev_notice(dev, format, arg...)		\
656 	dev_printk(KERN_NOTICE , dev , format , ## arg)
657 #define dev_info(dev, format, arg...)		\
658 	dev_printk(KERN_INFO , dev , format , ## arg)
659 
660 #if defined(DEBUG)
661 #define dev_dbg(dev, format, arg...)		\
662 	dev_printk(KERN_DEBUG , dev , format , ## arg)
663 #elif defined(CONFIG_DYNAMIC_DEBUG)
664 #define dev_dbg(dev, format, ...) do { \
665 	dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
666 	} while (0)
667 #else
668 #define dev_dbg(dev, format, arg...)		\
669 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
670 #endif
671 
672 #ifdef VERBOSE_DEBUG
673 #define dev_vdbg	dev_dbg
674 #else
675 
676 #define dev_vdbg(dev, format, arg...)		\
677 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
678 #endif
679 
680 /*
681  * dev_WARN() acts like dev_printk(), but with the key difference
682  * of using a WARN/WARN_ON to get the message out, including the
683  * file/line information and a backtrace.
684  */
685 #define dev_WARN(dev, format, arg...) \
686 	WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg);
687 
688 /* Create alias, so I can be autoloaded. */
689 #define MODULE_ALIAS_CHARDEV(major,minor) \
690 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
691 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
692 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
693 #endif /* _DEVICE_H_ */
694