xref: /linux-6.15/include/linux/device.h (revision 5f5bac82)
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 #define BUS_ID_SIZE		20
29 
30 struct device;
31 struct device_private;
32 struct device_driver;
33 struct driver_private;
34 struct class;
35 struct class_private;
36 struct bus_type;
37 struct bus_type_private;
38 
39 struct bus_attribute {
40 	struct attribute	attr;
41 	ssize_t (*show)(struct bus_type *bus, char *buf);
42 	ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
43 };
44 
45 #define BUS_ATTR(_name, _mode, _show, _store)	\
46 struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)
47 
48 extern int __must_check bus_create_file(struct bus_type *,
49 					struct bus_attribute *);
50 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
51 
52 struct bus_type {
53 	const char		*name;
54 	struct bus_attribute	*bus_attrs;
55 	struct device_attribute	*dev_attrs;
56 	struct driver_attribute	*drv_attrs;
57 
58 	int (*match)(struct device *dev, struct device_driver *drv);
59 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
60 	int (*probe)(struct device *dev);
61 	int (*remove)(struct device *dev);
62 	void (*shutdown)(struct device *dev);
63 
64 	int (*suspend)(struct device *dev, pm_message_t state);
65 	int (*resume)(struct device *dev);
66 
67 	struct dev_pm_ops *pm;
68 
69 	struct bus_type_private *p;
70 };
71 
72 extern int __must_check bus_register(struct bus_type *bus);
73 extern void bus_unregister(struct bus_type *bus);
74 
75 extern int __must_check bus_rescan_devices(struct bus_type *bus);
76 
77 /* iterator helpers for buses */
78 
79 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
80 		     int (*fn)(struct device *dev, void *data));
81 struct device *bus_find_device(struct bus_type *bus, struct device *start,
82 			       void *data,
83 			       int (*match)(struct device *dev, void *data));
84 struct device *bus_find_device_by_name(struct bus_type *bus,
85 				       struct device *start,
86 				       const char *name);
87 
88 int __must_check bus_for_each_drv(struct bus_type *bus,
89 				  struct device_driver *start, void *data,
90 				  int (*fn)(struct device_driver *, void *));
91 
92 void bus_sort_breadthfirst(struct bus_type *bus,
93 			   int (*compare)(const struct device *a,
94 					  const struct device *b));
95 /*
96  * Bus notifiers: Get notified of addition/removal of devices
97  * and binding/unbinding of drivers to devices.
98  * In the long run, it should be a replacement for the platform
99  * notify hooks.
100  */
101 struct notifier_block;
102 
103 extern int bus_register_notifier(struct bus_type *bus,
104 				 struct notifier_block *nb);
105 extern int bus_unregister_notifier(struct bus_type *bus,
106 				   struct notifier_block *nb);
107 
108 /* All 4 notifers below get called with the target struct device *
109  * as an argument. Note that those functions are likely to be called
110  * with the device semaphore held in the core, so be careful.
111  */
112 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
113 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device removed */
114 #define BUS_NOTIFY_BOUND_DRIVER		0x00000003 /* driver bound to device */
115 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000004 /* driver about to be
116 						      unbound */
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 	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 
196 	void (*class_release)(struct class *class);
197 	void (*dev_release)(struct device *dev);
198 
199 	int (*suspend)(struct device *dev, pm_message_t state);
200 	int (*resume)(struct device *dev);
201 
202 	struct dev_pm_ops *pm;
203 	struct class_private *p;
204 };
205 
206 struct class_dev_iter {
207 	struct klist_iter		ki;
208 	const struct device_type	*type;
209 };
210 
211 extern struct kobject *sysfs_dev_block_kobj;
212 extern struct kobject *sysfs_dev_char_kobj;
213 extern int __must_check __class_register(struct class *class,
214 					 struct lock_class_key *key);
215 extern void class_unregister(struct class *class);
216 
217 /* This is a #define to keep the compiler from merging different
218  * instances of the __key variable */
219 #define class_register(class)			\
220 ({						\
221 	static struct lock_class_key __key;	\
222 	__class_register(class, &__key);	\
223 })
224 
225 extern void class_dev_iter_init(struct class_dev_iter *iter,
226 				struct class *class,
227 				struct device *start,
228 				const struct device_type *type);
229 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
230 extern void class_dev_iter_exit(struct class_dev_iter *iter);
231 
232 extern int class_for_each_device(struct class *class, struct device *start,
233 				 void *data,
234 				 int (*fn)(struct device *dev, void *data));
235 extern struct device *class_find_device(struct class *class,
236 					struct device *start, void *data,
237 					int (*match)(struct device *, void *));
238 
239 struct class_attribute {
240 	struct attribute attr;
241 	ssize_t (*show)(struct class *class, char *buf);
242 	ssize_t (*store)(struct class *class, const char *buf, size_t count);
243 };
244 
245 #define CLASS_ATTR(_name, _mode, _show, _store)			\
246 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
247 
248 extern int __must_check class_create_file(struct class *class,
249 					  const struct class_attribute *attr);
250 extern void class_remove_file(struct class *class,
251 			      const struct class_attribute *attr);
252 
253 struct class_interface {
254 	struct list_head	node;
255 	struct class		*class;
256 
257 	int (*add_dev)		(struct device *, struct class_interface *);
258 	void (*remove_dev)	(struct device *, struct class_interface *);
259 };
260 
261 extern int __must_check class_interface_register(struct class_interface *);
262 extern void class_interface_unregister(struct class_interface *);
263 
264 extern struct class * __must_check __class_create(struct module *owner,
265 						  const char *name,
266 						  struct lock_class_key *key);
267 extern void class_destroy(struct class *cls);
268 
269 /* This is a #define to keep the compiler from merging different
270  * instances of the __key variable */
271 #define class_create(owner, name)		\
272 ({						\
273 	static struct lock_class_key __key;	\
274 	__class_create(owner, name, &__key);	\
275 })
276 
277 /*
278  * The type of device, "struct device" is embedded in. A class
279  * or bus can contain devices of different types
280  * like "partitions" and "disks", "mouse" and "event".
281  * This identifies the device type and carries type-specific
282  * information, equivalent to the kobj_type of a kobject.
283  * If "name" is specified, the uevent will contain it in
284  * the DEVTYPE variable.
285  */
286 struct device_type {
287 	const char *name;
288 	struct attribute_group **groups;
289 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
290 	void (*release)(struct device *dev);
291 
292 	struct dev_pm_ops *pm;
293 };
294 
295 /* interface for exporting device attributes */
296 struct device_attribute {
297 	struct attribute	attr;
298 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
299 			char *buf);
300 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
301 			 const char *buf, size_t count);
302 };
303 
304 #define DEVICE_ATTR(_name, _mode, _show, _store) \
305 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
306 
307 extern int __must_check device_create_file(struct device *device,
308 					   struct device_attribute *entry);
309 extern void device_remove_file(struct device *dev,
310 			       struct device_attribute *attr);
311 extern int __must_check device_create_bin_file(struct device *dev,
312 					       struct bin_attribute *attr);
313 extern void device_remove_bin_file(struct device *dev,
314 				   struct bin_attribute *attr);
315 extern int device_schedule_callback_owner(struct device *dev,
316 		void (*func)(struct device *dev), struct module *owner);
317 
318 /* This is a macro to avoid include problems with THIS_MODULE */
319 #define device_schedule_callback(dev, func)			\
320 	device_schedule_callback_owner(dev, func, THIS_MODULE)
321 
322 /* device resource management */
323 typedef void (*dr_release_t)(struct device *dev, void *res);
324 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
325 
326 #ifdef CONFIG_DEBUG_DEVRES
327 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
328 			     const char *name);
329 #define devres_alloc(release, size, gfp) \
330 	__devres_alloc(release, size, gfp, #release)
331 #else
332 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
333 #endif
334 extern void devres_free(void *res);
335 extern void devres_add(struct device *dev, void *res);
336 extern void *devres_find(struct device *dev, dr_release_t release,
337 			 dr_match_t match, void *match_data);
338 extern void *devres_get(struct device *dev, void *new_res,
339 			dr_match_t match, void *match_data);
340 extern void *devres_remove(struct device *dev, dr_release_t release,
341 			   dr_match_t match, void *match_data);
342 extern int devres_destroy(struct device *dev, dr_release_t release,
343 			  dr_match_t match, void *match_data);
344 
345 /* devres group */
346 extern void * __must_check devres_open_group(struct device *dev, void *id,
347 					     gfp_t gfp);
348 extern void devres_close_group(struct device *dev, void *id);
349 extern void devres_remove_group(struct device *dev, void *id);
350 extern int devres_release_group(struct device *dev, void *id);
351 
352 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
353 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
354 extern void devm_kfree(struct device *dev, void *p);
355 
356 struct device_dma_parameters {
357 	/*
358 	 * a low level driver may set these to teach IOMMU code about
359 	 * sg limitations.
360 	 */
361 	unsigned int max_segment_size;
362 	unsigned long segment_boundary_mask;
363 };
364 
365 struct device {
366 	struct device		*parent;
367 
368 	struct device_private	*p;
369 
370 	struct kobject kobj;
371 	const char		*init_name; /* initial name of the device */
372 	struct device_type	*type;
373 
374 	struct semaphore	sem;	/* semaphore to synchronize calls to
375 					 * its driver.
376 					 */
377 
378 	struct bus_type	*bus;		/* type of bus device is on */
379 	struct device_driver *driver;	/* which driver has allocated this
380 					   device */
381 	void		*driver_data;	/* data private to the driver */
382 	void		*platform_data;	/* Platform specific data, device
383 					   core doesn't touch it */
384 	struct dev_pm_info	power;
385 
386 #ifdef CONFIG_NUMA
387 	int		numa_node;	/* NUMA node this device is close to */
388 #endif
389 	u64		*dma_mask;	/* dma mask (if dma'able device) */
390 	u64		coherent_dma_mask;/* Like dma_mask, but for
391 					     alloc_coherent mappings as
392 					     not all hardware supports
393 					     64 bit addresses for consistent
394 					     allocations such descriptors. */
395 
396 	struct device_dma_parameters *dma_parms;
397 
398 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
399 
400 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
401 					     override */
402 	/* arch specific additions */
403 	struct dev_archdata	archdata;
404 
405 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
406 
407 	spinlock_t		devres_lock;
408 	struct list_head	devres_head;
409 
410 	struct klist_node	knode_class;
411 	struct class		*class;
412 	struct attribute_group	**groups;	/* optional groups */
413 
414 	void	(*release)(struct device *dev);
415 };
416 
417 /* Get the wakeup routines, which depend on struct device */
418 #include <linux/pm_wakeup.h>
419 
420 static inline const char *dev_name(const struct device *dev)
421 {
422 	return kobject_name(&dev->kobj);
423 }
424 
425 extern int dev_set_name(struct device *dev, const char *name, ...)
426 			__attribute__((format(printf, 2, 3)));
427 
428 #ifdef CONFIG_NUMA
429 static inline int dev_to_node(struct device *dev)
430 {
431 	return dev->numa_node;
432 }
433 static inline void set_dev_node(struct device *dev, int node)
434 {
435 	dev->numa_node = node;
436 }
437 #else
438 static inline int dev_to_node(struct device *dev)
439 {
440 	return -1;
441 }
442 static inline void set_dev_node(struct device *dev, int node)
443 {
444 }
445 #endif
446 
447 static inline void *dev_get_drvdata(const struct device *dev)
448 {
449 	return dev->driver_data;
450 }
451 
452 static inline void dev_set_drvdata(struct device *dev, void *data)
453 {
454 	dev->driver_data = data;
455 }
456 
457 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
458 {
459 	return dev->kobj.uevent_suppress;
460 }
461 
462 static inline void dev_set_uevent_suppress(struct device *dev, int val)
463 {
464 	dev->kobj.uevent_suppress = val;
465 }
466 
467 static inline int device_is_registered(struct device *dev)
468 {
469 	return dev->kobj.state_in_sysfs;
470 }
471 
472 void driver_init(void);
473 
474 /*
475  * High level routines for use by the bus drivers
476  */
477 extern int __must_check device_register(struct device *dev);
478 extern void device_unregister(struct device *dev);
479 extern void device_initialize(struct device *dev);
480 extern int __must_check device_add(struct device *dev);
481 extern void device_del(struct device *dev);
482 extern int device_for_each_child(struct device *dev, void *data,
483 		     int (*fn)(struct device *dev, void *data));
484 extern struct device *device_find_child(struct device *dev, void *data,
485 				int (*match)(struct device *dev, void *data));
486 extern int device_rename(struct device *dev, char *new_name);
487 extern int device_move(struct device *dev, struct device *new_parent,
488 		       enum dpm_order dpm_order);
489 
490 /*
491  * Root device objects for grouping under /sys/devices
492  */
493 extern struct device *__root_device_register(const char *name,
494 					     struct module *owner);
495 static inline struct device *root_device_register(const char *name)
496 {
497 	return __root_device_register(name, THIS_MODULE);
498 }
499 extern void root_device_unregister(struct device *root);
500 
501 /*
502  * Manual binding of a device to driver. See drivers/base/bus.c
503  * for information on use.
504  */
505 extern int __must_check device_bind_driver(struct device *dev);
506 extern void device_release_driver(struct device *dev);
507 extern int  __must_check device_attach(struct device *dev);
508 extern int __must_check driver_attach(struct device_driver *drv);
509 extern int __must_check device_reprobe(struct device *dev);
510 
511 /*
512  * Easy functions for dynamically creating devices on the fly
513  */
514 extern struct device *device_create_vargs(struct class *cls,
515 					  struct device *parent,
516 					  dev_t devt,
517 					  void *drvdata,
518 					  const char *fmt,
519 					  va_list vargs);
520 extern struct device *device_create(struct class *cls, struct device *parent,
521 				    dev_t devt, void *drvdata,
522 				    const char *fmt, ...)
523 				    __attribute__((format(printf, 5, 6)));
524 extern void device_destroy(struct class *cls, dev_t devt);
525 
526 /*
527  * Platform "fixup" functions - allow the platform to have their say
528  * about devices and actions that the general device layer doesn't
529  * know about.
530  */
531 /* Notify platform of device discovery */
532 extern int (*platform_notify)(struct device *dev);
533 
534 extern int (*platform_notify_remove)(struct device *dev);
535 
536 
537 /**
538  * get_device - atomically increment the reference count for the device.
539  *
540  */
541 extern struct device *get_device(struct device *dev);
542 extern void put_device(struct device *dev);
543 
544 extern void wait_for_device_probe(void);
545 
546 /* drivers/base/power/shutdown.c */
547 extern void device_shutdown(void);
548 
549 /* drivers/base/sys.c */
550 extern void sysdev_shutdown(void);
551 
552 /* debugging and troubleshooting/diagnostic helpers. */
553 extern const char *dev_driver_string(const struct device *dev);
554 #define dev_printk(level, dev, format, arg...)	\
555 	printk(level "%s %s: " format , dev_driver_string(dev) , \
556 	       dev_name(dev) , ## arg)
557 
558 #define dev_emerg(dev, format, arg...)		\
559 	dev_printk(KERN_EMERG , dev , format , ## arg)
560 #define dev_alert(dev, format, arg...)		\
561 	dev_printk(KERN_ALERT , dev , format , ## arg)
562 #define dev_crit(dev, format, arg...)		\
563 	dev_printk(KERN_CRIT , dev , format , ## arg)
564 #define dev_err(dev, format, arg...)		\
565 	dev_printk(KERN_ERR , dev , format , ## arg)
566 #define dev_warn(dev, format, arg...)		\
567 	dev_printk(KERN_WARNING , dev , format , ## arg)
568 #define dev_notice(dev, format, arg...)		\
569 	dev_printk(KERN_NOTICE , dev , format , ## arg)
570 #define dev_info(dev, format, arg...)		\
571 	dev_printk(KERN_INFO , dev , format , ## arg)
572 
573 #if defined(DEBUG)
574 #define dev_dbg(dev, format, arg...)		\
575 	dev_printk(KERN_DEBUG , dev , format , ## arg)
576 #elif defined(CONFIG_DYNAMIC_DEBUG)
577 #define dev_dbg(dev, format, ...) do { \
578 	dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
579 	} while (0)
580 #else
581 #define dev_dbg(dev, format, arg...)		\
582 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
583 #endif
584 
585 #ifdef VERBOSE_DEBUG
586 #define dev_vdbg	dev_dbg
587 #else
588 
589 #define dev_vdbg(dev, format, arg...)		\
590 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
591 #endif
592 
593 /*
594  * dev_WARN() acts like dev_printk(), but with the key difference
595  * of using a WARN/WARN_ON to get the message out, including the
596  * file/line information and a backtrace.
597  */
598 #define dev_WARN(dev, format, arg...) \
599 	WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg);
600 
601 /* Create alias, so I can be autoloaded. */
602 #define MODULE_ALIAS_CHARDEV(major,minor) \
603 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
604 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
605 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
606 #endif /* _DEVICE_H_ */
607