xref: /linux-6.15/include/linux/device.h (revision fea966f7)
1 /*
2  * device.h - generic, centralized driver model
3  *
4  * Copyright (c) 2001-2003 Patrick Mochel <[email protected]>
5  * Copyright (c) 2004-2007 Greg Kroah-Hartman <[email protected]>
6  *
7  * This file is released under the GPLv2
8  *
9  * See Documentation/driver-model/ for more information.
10  */
11 
12 #ifndef _DEVICE_H_
13 #define _DEVICE_H_
14 
15 #include <linux/ioport.h>
16 #include <linux/kobject.h>
17 #include <linux/klist.h>
18 #include <linux/list.h>
19 #include <linux/lockdep.h>
20 #include <linux/compiler.h>
21 #include <linux/types.h>
22 #include <linux/module.h>
23 #include <linux/pm.h>
24 #include <linux/semaphore.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 
37 struct bus_attribute {
38 	struct attribute	attr;
39 	ssize_t (*show)(struct bus_type *bus, char *buf);
40 	ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
41 };
42 
43 #define BUS_ATTR(_name, _mode, _show, _store)	\
44 struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)
45 
46 extern int __must_check bus_create_file(struct bus_type *,
47 					struct bus_attribute *);
48 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
49 
50 struct bus_type {
51 	const char		*name;
52 	struct bus_attribute	*bus_attrs;
53 	struct device_attribute	*dev_attrs;
54 	struct driver_attribute	*drv_attrs;
55 
56 	int (*match)(struct device *dev, struct device_driver *drv);
57 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
58 	int (*probe)(struct device *dev);
59 	int (*remove)(struct device *dev);
60 	void (*shutdown)(struct device *dev);
61 
62 	int (*suspend)(struct device *dev, pm_message_t state);
63 	int (*resume)(struct device *dev);
64 
65 	const struct dev_pm_ops *pm;
66 
67 	struct bus_type_private *p;
68 };
69 
70 extern int __must_check bus_register(struct bus_type *bus);
71 extern void bus_unregister(struct bus_type *bus);
72 
73 extern int __must_check bus_rescan_devices(struct bus_type *bus);
74 
75 /* iterator helpers for buses */
76 
77 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
78 		     int (*fn)(struct device *dev, void *data));
79 struct device *bus_find_device(struct bus_type *bus, struct device *start,
80 			       void *data,
81 			       int (*match)(struct device *dev, void *data));
82 struct device *bus_find_device_by_name(struct bus_type *bus,
83 				       struct device *start,
84 				       const char *name);
85 
86 int __must_check bus_for_each_drv(struct bus_type *bus,
87 				  struct device_driver *start, void *data,
88 				  int (*fn)(struct device_driver *, void *));
89 
90 void bus_sort_breadthfirst(struct bus_type *bus,
91 			   int (*compare)(const struct device *a,
92 					  const struct device *b));
93 /*
94  * Bus notifiers: Get notified of addition/removal of devices
95  * and binding/unbinding of drivers to devices.
96  * In the long run, it should be a replacement for the platform
97  * notify hooks.
98  */
99 struct notifier_block;
100 
101 extern int bus_register_notifier(struct bus_type *bus,
102 				 struct notifier_block *nb);
103 extern int bus_unregister_notifier(struct bus_type *bus,
104 				   struct notifier_block *nb);
105 
106 /* All 4 notifers below get called with the target struct device *
107  * as an argument. Note that those functions are likely to be called
108  * with the device semaphore held in the core, so be careful.
109  */
110 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
111 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device removed */
112 #define BUS_NOTIFY_BOUND_DRIVER		0x00000003 /* driver bound to device */
113 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000004 /* driver about to be
114 						      unbound */
115 #define BUS_NOTIFY_UNBOUND_DRIVER	0x00000005 /* driver is unbound
116 						      from the device */
117 
118 extern struct kset *bus_get_kset(struct bus_type *bus);
119 extern struct klist *bus_get_device_klist(struct bus_type *bus);
120 
121 struct device_driver {
122 	const char		*name;
123 	struct bus_type		*bus;
124 
125 	struct module		*owner;
126 	const char 		*mod_name;	/* used for built-in modules */
127 
128 	int (*probe) (struct device *dev);
129 	int (*remove) (struct device *dev);
130 	void (*shutdown) (struct device *dev);
131 	int (*suspend) (struct device *dev, pm_message_t state);
132 	int (*resume) (struct device *dev);
133 	struct attribute_group **groups;
134 
135 	const struct dev_pm_ops *pm;
136 
137 	struct driver_private *p;
138 };
139 
140 
141 extern int __must_check driver_register(struct device_driver *drv);
142 extern void driver_unregister(struct device_driver *drv);
143 
144 extern struct device_driver *get_driver(struct device_driver *drv);
145 extern void put_driver(struct device_driver *drv);
146 extern struct device_driver *driver_find(const char *name,
147 					 struct bus_type *bus);
148 extern int driver_probe_done(void);
149 extern void wait_for_device_probe(void);
150 
151 
152 /* sysfs interface for exporting driver attributes */
153 
154 struct driver_attribute {
155 	struct attribute attr;
156 	ssize_t (*show)(struct device_driver *driver, char *buf);
157 	ssize_t (*store)(struct device_driver *driver, const char *buf,
158 			 size_t count);
159 };
160 
161 #define DRIVER_ATTR(_name, _mode, _show, _store)	\
162 struct driver_attribute driver_attr_##_name =		\
163 	__ATTR(_name, _mode, _show, _store)
164 
165 extern int __must_check driver_create_file(struct device_driver *driver,
166 					   struct driver_attribute *attr);
167 extern void driver_remove_file(struct device_driver *driver,
168 			       struct driver_attribute *attr);
169 
170 extern int __must_check driver_add_kobj(struct device_driver *drv,
171 					struct kobject *kobj,
172 					const char *fmt, ...);
173 
174 extern int __must_check driver_for_each_device(struct device_driver *drv,
175 					       struct device *start,
176 					       void *data,
177 					       int (*fn)(struct device *dev,
178 							 void *));
179 struct device *driver_find_device(struct device_driver *drv,
180 				  struct device *start, void *data,
181 				  int (*match)(struct device *dev, void *data));
182 
183 /*
184  * device classes
185  */
186 struct class {
187 	const char		*name;
188 	struct module		*owner;
189 
190 	struct class_attribute		*class_attrs;
191 	struct device_attribute		*dev_attrs;
192 	struct kobject			*dev_kobj;
193 
194 	int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
195 	char *(*nodename)(struct device *dev);
196 
197 	void (*class_release)(struct class *class);
198 	void (*dev_release)(struct device *dev);
199 
200 	int (*suspend)(struct device *dev, pm_message_t state);
201 	int (*resume)(struct device *dev);
202 
203 	const struct dev_pm_ops *pm;
204 
205 	struct class_private *p;
206 };
207 
208 struct class_dev_iter {
209 	struct klist_iter		ki;
210 	const struct device_type	*type;
211 };
212 
213 extern struct kobject *sysfs_dev_block_kobj;
214 extern struct kobject *sysfs_dev_char_kobj;
215 extern int __must_check __class_register(struct class *class,
216 					 struct lock_class_key *key);
217 extern void class_unregister(struct class *class);
218 
219 /* This is a #define to keep the compiler from merging different
220  * instances of the __key variable */
221 #define class_register(class)			\
222 ({						\
223 	static struct lock_class_key __key;	\
224 	__class_register(class, &__key);	\
225 })
226 
227 extern void class_dev_iter_init(struct class_dev_iter *iter,
228 				struct class *class,
229 				struct device *start,
230 				const struct device_type *type);
231 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
232 extern void class_dev_iter_exit(struct class_dev_iter *iter);
233 
234 extern int class_for_each_device(struct class *class, struct device *start,
235 				 void *data,
236 				 int (*fn)(struct device *dev, void *data));
237 extern struct device *class_find_device(struct class *class,
238 					struct device *start, void *data,
239 					int (*match)(struct device *, void *));
240 
241 struct class_attribute {
242 	struct attribute attr;
243 	ssize_t (*show)(struct class *class, char *buf);
244 	ssize_t (*store)(struct class *class, const char *buf, size_t count);
245 };
246 
247 #define CLASS_ATTR(_name, _mode, _show, _store)			\
248 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
249 
250 extern int __must_check class_create_file(struct class *class,
251 					  const struct class_attribute *attr);
252 extern void class_remove_file(struct class *class,
253 			      const struct class_attribute *attr);
254 
255 struct class_interface {
256 	struct list_head	node;
257 	struct class		*class;
258 
259 	int (*add_dev)		(struct device *, struct class_interface *);
260 	void (*remove_dev)	(struct device *, struct class_interface *);
261 };
262 
263 extern int __must_check class_interface_register(struct class_interface *);
264 extern void class_interface_unregister(struct class_interface *);
265 
266 extern struct class * __must_check __class_create(struct module *owner,
267 						  const char *name,
268 						  struct lock_class_key *key);
269 extern void class_destroy(struct class *cls);
270 
271 /* This is a #define to keep the compiler from merging different
272  * instances of the __key variable */
273 #define class_create(owner, name)		\
274 ({						\
275 	static struct lock_class_key __key;	\
276 	__class_create(owner, name, &__key);	\
277 })
278 
279 /*
280  * The type of device, "struct device" is embedded in. A class
281  * or bus can contain devices of different types
282  * like "partitions" and "disks", "mouse" and "event".
283  * This identifies the device type and carries type-specific
284  * information, equivalent to the kobj_type of a kobject.
285  * If "name" is specified, the uevent will contain it in
286  * the DEVTYPE variable.
287  */
288 struct device_type {
289 	const char *name;
290 	struct attribute_group **groups;
291 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
292 	char *(*nodename)(struct device *dev);
293 	void (*release)(struct device *dev);
294 
295 	const struct dev_pm_ops *pm;
296 };
297 
298 /* interface for exporting device attributes */
299 struct device_attribute {
300 	struct attribute	attr;
301 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
302 			char *buf);
303 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
304 			 const char *buf, size_t count);
305 };
306 
307 #define DEVICE_ATTR(_name, _mode, _show, _store) \
308 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
309 
310 extern int __must_check device_create_file(struct device *device,
311 					   struct device_attribute *entry);
312 extern void device_remove_file(struct device *dev,
313 			       struct device_attribute *attr);
314 extern int __must_check device_create_bin_file(struct device *dev,
315 					       struct bin_attribute *attr);
316 extern void device_remove_bin_file(struct device *dev,
317 				   struct bin_attribute *attr);
318 extern int device_schedule_callback_owner(struct device *dev,
319 		void (*func)(struct device *dev), struct module *owner);
320 
321 /* This is a macro to avoid include problems with THIS_MODULE */
322 #define device_schedule_callback(dev, func)			\
323 	device_schedule_callback_owner(dev, func, THIS_MODULE)
324 
325 /* device resource management */
326 typedef void (*dr_release_t)(struct device *dev, void *res);
327 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
328 
329 #ifdef CONFIG_DEBUG_DEVRES
330 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
331 			     const char *name);
332 #define devres_alloc(release, size, gfp) \
333 	__devres_alloc(release, size, gfp, #release)
334 #else
335 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
336 #endif
337 extern void devres_free(void *res);
338 extern void devres_add(struct device *dev, void *res);
339 extern void *devres_find(struct device *dev, dr_release_t release,
340 			 dr_match_t match, void *match_data);
341 extern void *devres_get(struct device *dev, void *new_res,
342 			dr_match_t match, void *match_data);
343 extern void *devres_remove(struct device *dev, dr_release_t release,
344 			   dr_match_t match, void *match_data);
345 extern int devres_destroy(struct device *dev, dr_release_t release,
346 			  dr_match_t match, void *match_data);
347 
348 /* devres group */
349 extern void * __must_check devres_open_group(struct device *dev, void *id,
350 					     gfp_t gfp);
351 extern void devres_close_group(struct device *dev, void *id);
352 extern void devres_remove_group(struct device *dev, void *id);
353 extern int devres_release_group(struct device *dev, void *id);
354 
355 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
356 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
357 extern void devm_kfree(struct device *dev, void *p);
358 
359 struct device_dma_parameters {
360 	/*
361 	 * a low level driver may set these to teach IOMMU code about
362 	 * sg limitations.
363 	 */
364 	unsigned int max_segment_size;
365 	unsigned long segment_boundary_mask;
366 };
367 
368 struct device {
369 	struct device		*parent;
370 
371 	struct device_private	*p;
372 
373 	struct kobject kobj;
374 	const char		*init_name; /* initial name of the device */
375 	struct device_type	*type;
376 
377 	struct semaphore	sem;	/* semaphore to synchronize calls to
378 					 * its driver.
379 					 */
380 
381 	struct bus_type	*bus;		/* type of bus device is on */
382 	struct device_driver *driver;	/* which driver has allocated this
383 					   device */
384 	void		*driver_data;	/* data private to the driver */
385 	void		*platform_data;	/* Platform specific data, device
386 					   core doesn't touch it */
387 	struct dev_pm_info	power;
388 
389 #ifdef CONFIG_NUMA
390 	int		numa_node;	/* NUMA node this device is close to */
391 #endif
392 	u64		*dma_mask;	/* dma mask (if dma'able device) */
393 	u64		coherent_dma_mask;/* Like dma_mask, but for
394 					     alloc_coherent mappings as
395 					     not all hardware supports
396 					     64 bit addresses for consistent
397 					     allocations such descriptors. */
398 
399 	struct device_dma_parameters *dma_parms;
400 
401 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
402 
403 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
404 					     override */
405 	/* arch specific additions */
406 	struct dev_archdata	archdata;
407 
408 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
409 
410 	spinlock_t		devres_lock;
411 	struct list_head	devres_head;
412 
413 	struct klist_node	knode_class;
414 	struct class		*class;
415 	struct attribute_group	**groups;	/* optional groups */
416 
417 	void	(*release)(struct device *dev);
418 };
419 
420 /* Get the wakeup routines, which depend on struct device */
421 #include <linux/pm_wakeup.h>
422 
423 static inline const char *dev_name(const struct device *dev)
424 {
425 	return kobject_name(&dev->kobj);
426 }
427 
428 extern int dev_set_name(struct device *dev, const char *name, ...)
429 			__attribute__((format(printf, 2, 3)));
430 
431 #ifdef CONFIG_NUMA
432 static inline int dev_to_node(struct device *dev)
433 {
434 	return dev->numa_node;
435 }
436 static inline void set_dev_node(struct device *dev, int node)
437 {
438 	dev->numa_node = node;
439 }
440 #else
441 static inline int dev_to_node(struct device *dev)
442 {
443 	return -1;
444 }
445 static inline void set_dev_node(struct device *dev, int node)
446 {
447 }
448 #endif
449 
450 static inline void *dev_get_drvdata(const struct device *dev)
451 {
452 	return dev->driver_data;
453 }
454 
455 static inline void dev_set_drvdata(struct device *dev, void *data)
456 {
457 	dev->driver_data = data;
458 }
459 
460 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
461 {
462 	return dev->kobj.uevent_suppress;
463 }
464 
465 static inline void dev_set_uevent_suppress(struct device *dev, int val)
466 {
467 	dev->kobj.uevent_suppress = val;
468 }
469 
470 static inline int device_is_registered(struct device *dev)
471 {
472 	return dev->kobj.state_in_sysfs;
473 }
474 
475 void driver_init(void);
476 
477 /*
478  * High level routines for use by the bus drivers
479  */
480 extern int __must_check device_register(struct device *dev);
481 extern void device_unregister(struct device *dev);
482 extern void device_initialize(struct device *dev);
483 extern int __must_check device_add(struct device *dev);
484 extern void device_del(struct device *dev);
485 extern int device_for_each_child(struct device *dev, void *data,
486 		     int (*fn)(struct device *dev, void *data));
487 extern struct device *device_find_child(struct device *dev, void *data,
488 				int (*match)(struct device *dev, void *data));
489 extern int device_rename(struct device *dev, char *new_name);
490 extern int device_move(struct device *dev, struct device *new_parent,
491 		       enum dpm_order dpm_order);
492 extern const char *device_get_nodename(struct device *dev, const char **tmp);
493 
494 /*
495  * Root device objects for grouping under /sys/devices
496  */
497 extern struct device *__root_device_register(const char *name,
498 					     struct module *owner);
499 static inline struct device *root_device_register(const char *name)
500 {
501 	return __root_device_register(name, THIS_MODULE);
502 }
503 extern void root_device_unregister(struct device *root);
504 
505 /*
506  * Manual binding of a device to driver. See drivers/base/bus.c
507  * for information on use.
508  */
509 extern int __must_check device_bind_driver(struct device *dev);
510 extern void device_release_driver(struct device *dev);
511 extern int  __must_check device_attach(struct device *dev);
512 extern int __must_check driver_attach(struct device_driver *drv);
513 extern int __must_check device_reprobe(struct device *dev);
514 
515 /*
516  * Easy functions for dynamically creating devices on the fly
517  */
518 extern struct device *device_create_vargs(struct class *cls,
519 					  struct device *parent,
520 					  dev_t devt,
521 					  void *drvdata,
522 					  const char *fmt,
523 					  va_list vargs);
524 extern struct device *device_create(struct class *cls, struct device *parent,
525 				    dev_t devt, void *drvdata,
526 				    const char *fmt, ...)
527 				    __attribute__((format(printf, 5, 6)));
528 extern void device_destroy(struct class *cls, dev_t devt);
529 
530 /*
531  * Platform "fixup" functions - allow the platform to have their say
532  * about devices and actions that the general device layer doesn't
533  * know about.
534  */
535 /* Notify platform of device discovery */
536 extern int (*platform_notify)(struct device *dev);
537 
538 extern int (*platform_notify_remove)(struct device *dev);
539 
540 
541 /**
542  * get_device - atomically increment the reference count for the device.
543  *
544  */
545 extern struct device *get_device(struct device *dev);
546 extern void put_device(struct device *dev);
547 
548 extern void wait_for_device_probe(void);
549 
550 /* drivers/base/power/shutdown.c */
551 extern void device_shutdown(void);
552 
553 /* drivers/base/sys.c */
554 extern void sysdev_shutdown(void);
555 
556 /* debugging and troubleshooting/diagnostic helpers. */
557 extern const char *dev_driver_string(const struct device *dev);
558 #define dev_printk(level, dev, format, arg...)	\
559 	printk(level "%s %s: " format , dev_driver_string(dev) , \
560 	       dev_name(dev) , ## arg)
561 
562 #define dev_emerg(dev, format, arg...)		\
563 	dev_printk(KERN_EMERG , dev , format , ## arg)
564 #define dev_alert(dev, format, arg...)		\
565 	dev_printk(KERN_ALERT , dev , format , ## arg)
566 #define dev_crit(dev, format, arg...)		\
567 	dev_printk(KERN_CRIT , dev , format , ## arg)
568 #define dev_err(dev, format, arg...)		\
569 	dev_printk(KERN_ERR , dev , format , ## arg)
570 #define dev_warn(dev, format, arg...)		\
571 	dev_printk(KERN_WARNING , dev , format , ## arg)
572 #define dev_notice(dev, format, arg...)		\
573 	dev_printk(KERN_NOTICE , dev , format , ## arg)
574 #define dev_info(dev, format, arg...)		\
575 	dev_printk(KERN_INFO , dev , format , ## arg)
576 
577 #if defined(DEBUG)
578 #define dev_dbg(dev, format, arg...)		\
579 	dev_printk(KERN_DEBUG , dev , format , ## arg)
580 #elif defined(CONFIG_DYNAMIC_DEBUG)
581 #define dev_dbg(dev, format, ...) do { \
582 	dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
583 	} while (0)
584 #else
585 #define dev_dbg(dev, format, arg...)		\
586 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
587 #endif
588 
589 #ifdef VERBOSE_DEBUG
590 #define dev_vdbg	dev_dbg
591 #else
592 
593 #define dev_vdbg(dev, format, arg...)		\
594 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
595 #endif
596 
597 /*
598  * dev_WARN() acts like dev_printk(), but with the key difference
599  * of using a WARN/WARN_ON to get the message out, including the
600  * file/line information and a backtrace.
601  */
602 #define dev_WARN(dev, format, arg...) \
603 	WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg);
604 
605 /* Create alias, so I can be autoloaded. */
606 #define MODULE_ALIAS_CHARDEV(major,minor) \
607 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
608 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
609 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
610 #endif /* _DEVICE_H_ */
611