xref: /linux-6.15/include/linux/device.h (revision b8bb7671)
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 (*suspend_late)(struct device *dev, pm_message_t state);
66 	int (*resume_early)(struct device *dev);
67 	int (*resume)(struct device *dev);
68 
69 	struct dev_pm_ops *pm;
70 
71 	struct bus_type_private *p;
72 };
73 
74 extern int __must_check bus_register(struct bus_type *bus);
75 extern void bus_unregister(struct bus_type *bus);
76 
77 extern int __must_check bus_rescan_devices(struct bus_type *bus);
78 
79 /* iterator helpers for buses */
80 
81 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
82 		     int (*fn)(struct device *dev, void *data));
83 struct device *bus_find_device(struct bus_type *bus, struct device *start,
84 			       void *data,
85 			       int (*match)(struct device *dev, void *data));
86 struct device *bus_find_device_by_name(struct bus_type *bus,
87 				       struct device *start,
88 				       const char *name);
89 
90 int __must_check bus_for_each_drv(struct bus_type *bus,
91 				  struct device_driver *start, void *data,
92 				  int (*fn)(struct device_driver *, void *));
93 
94 void bus_sort_breadthfirst(struct bus_type *bus,
95 			   int (*compare)(const struct device *a,
96 					  const struct device *b));
97 /*
98  * Bus notifiers: Get notified of addition/removal of devices
99  * and binding/unbinding of drivers to devices.
100  * In the long run, it should be a replacement for the platform
101  * notify hooks.
102  */
103 struct notifier_block;
104 
105 extern int bus_register_notifier(struct bus_type *bus,
106 				 struct notifier_block *nb);
107 extern int bus_unregister_notifier(struct bus_type *bus,
108 				   struct notifier_block *nb);
109 
110 /* All 4 notifers below get called with the target struct device *
111  * as an argument. Note that those functions are likely to be called
112  * with the device semaphore held in the core, so be careful.
113  */
114 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
115 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device removed */
116 #define BUS_NOTIFY_BOUND_DRIVER		0x00000003 /* driver bound to device */
117 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000004 /* driver about to be
118 						      unbound */
119 
120 extern struct kset *bus_get_kset(struct bus_type *bus);
121 extern struct klist *bus_get_device_klist(struct bus_type *bus);
122 
123 struct device_driver {
124 	const char		*name;
125 	struct bus_type		*bus;
126 
127 	struct module		*owner;
128 	const char 		*mod_name;	/* used for built-in modules */
129 
130 	int (*probe) (struct device *dev);
131 	int (*remove) (struct device *dev);
132 	void (*shutdown) (struct device *dev);
133 	int (*suspend) (struct device *dev, pm_message_t state);
134 	int (*resume) (struct device *dev);
135 	struct attribute_group **groups;
136 
137 	struct dev_pm_ops *pm;
138 
139 	struct driver_private *p;
140 };
141 
142 
143 extern int __must_check driver_register(struct device_driver *drv);
144 extern void driver_unregister(struct device_driver *drv);
145 
146 extern struct device_driver *get_driver(struct device_driver *drv);
147 extern void put_driver(struct device_driver *drv);
148 extern struct device_driver *driver_find(const char *name,
149 					 struct bus_type *bus);
150 extern int driver_probe_done(void);
151 extern void wait_for_device_probe(void);
152 
153 
154 /* sysfs interface for exporting driver attributes */
155 
156 struct driver_attribute {
157 	struct attribute attr;
158 	ssize_t (*show)(struct device_driver *driver, char *buf);
159 	ssize_t (*store)(struct device_driver *driver, const char *buf,
160 			 size_t count);
161 };
162 
163 #define DRIVER_ATTR(_name, _mode, _show, _store)	\
164 struct driver_attribute driver_attr_##_name =		\
165 	__ATTR(_name, _mode, _show, _store)
166 
167 extern int __must_check driver_create_file(struct device_driver *driver,
168 					   struct driver_attribute *attr);
169 extern void driver_remove_file(struct device_driver *driver,
170 			       struct driver_attribute *attr);
171 
172 extern int __must_check driver_add_kobj(struct device_driver *drv,
173 					struct kobject *kobj,
174 					const char *fmt, ...);
175 
176 extern int __must_check driver_for_each_device(struct device_driver *drv,
177 					       struct device *start,
178 					       void *data,
179 					       int (*fn)(struct device *dev,
180 							 void *));
181 struct device *driver_find_device(struct device_driver *drv,
182 				  struct device *start, void *data,
183 				  int (*match)(struct device *dev, void *data));
184 
185 /*
186  * device classes
187  */
188 struct class {
189 	const char		*name;
190 	struct module		*owner;
191 
192 	struct class_attribute		*class_attrs;
193 	struct device_attribute		*dev_attrs;
194 	struct kobject			*dev_kobj;
195 
196 	int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
197 
198 	void (*class_release)(struct class *class);
199 	void (*dev_release)(struct device *dev);
200 
201 	int (*suspend)(struct device *dev, pm_message_t state);
202 	int (*resume)(struct device *dev);
203 
204 	struct dev_pm_ops *pm;
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 	void (*release)(struct device *dev);
293 
294 	int (*suspend)(struct device *dev, pm_message_t state);
295 	int (*resume)(struct device *dev);
296 
297 	struct dev_pm_ops *pm;
298 };
299 
300 /* interface for exporting device attributes */
301 struct device_attribute {
302 	struct attribute	attr;
303 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
304 			char *buf);
305 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
306 			 const char *buf, size_t count);
307 };
308 
309 #define DEVICE_ATTR(_name, _mode, _show, _store) \
310 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
311 
312 extern int __must_check device_create_file(struct device *device,
313 					   struct device_attribute *entry);
314 extern void device_remove_file(struct device *dev,
315 			       struct device_attribute *attr);
316 extern int __must_check device_create_bin_file(struct device *dev,
317 					       struct bin_attribute *attr);
318 extern void device_remove_bin_file(struct device *dev,
319 				   struct bin_attribute *attr);
320 extern int device_schedule_callback_owner(struct device *dev,
321 		void (*func)(struct device *dev), struct module *owner);
322 
323 /* This is a macro to avoid include problems with THIS_MODULE */
324 #define device_schedule_callback(dev, func)			\
325 	device_schedule_callback_owner(dev, func, THIS_MODULE)
326 
327 /* device resource management */
328 typedef void (*dr_release_t)(struct device *dev, void *res);
329 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
330 
331 #ifdef CONFIG_DEBUG_DEVRES
332 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
333 			     const char *name);
334 #define devres_alloc(release, size, gfp) \
335 	__devres_alloc(release, size, gfp, #release)
336 #else
337 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
338 #endif
339 extern void devres_free(void *res);
340 extern void devres_add(struct device *dev, void *res);
341 extern void *devres_find(struct device *dev, dr_release_t release,
342 			 dr_match_t match, void *match_data);
343 extern void *devres_get(struct device *dev, void *new_res,
344 			dr_match_t match, void *match_data);
345 extern void *devres_remove(struct device *dev, dr_release_t release,
346 			   dr_match_t match, void *match_data);
347 extern int devres_destroy(struct device *dev, dr_release_t release,
348 			  dr_match_t match, void *match_data);
349 
350 /* devres group */
351 extern void * __must_check devres_open_group(struct device *dev, void *id,
352 					     gfp_t gfp);
353 extern void devres_close_group(struct device *dev, void *id);
354 extern void devres_remove_group(struct device *dev, void *id);
355 extern int devres_release_group(struct device *dev, void *id);
356 
357 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
358 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
359 extern void devm_kfree(struct device *dev, void *p);
360 
361 struct device_dma_parameters {
362 	/*
363 	 * a low level driver may set these to teach IOMMU code about
364 	 * sg limitations.
365 	 */
366 	unsigned int max_segment_size;
367 	unsigned long segment_boundary_mask;
368 };
369 
370 struct device {
371 	struct device		*parent;
372 
373 	struct device_private	*p;
374 
375 	struct kobject kobj;
376 	const char		*init_name; /* initial name of the device */
377 	struct device_type	*type;
378 
379 	struct semaphore	sem;	/* semaphore to synchronize calls to
380 					 * its driver.
381 					 */
382 
383 	struct bus_type	*bus;		/* type of bus device is on */
384 	struct device_driver *driver;	/* which driver has allocated this
385 					   device */
386 	void		*driver_data;	/* data private to the driver */
387 
388 	void		*platform_data;	/* We will remove platform_data
389 					   field if all platform devices
390 					   pass its platform specific data
391 					   from platform_device->platform_data,
392 					   other kind of devices should not
393 					   use platform_data. */
394 	struct dev_pm_info	power;
395 
396 #ifdef CONFIG_NUMA
397 	int		numa_node;	/* NUMA node this device is close to */
398 #endif
399 	u64		*dma_mask;	/* dma mask (if dma'able device) */
400 	u64		coherent_dma_mask;/* Like dma_mask, but for
401 					     alloc_coherent mappings as
402 					     not all hardware supports
403 					     64 bit addresses for consistent
404 					     allocations such descriptors. */
405 
406 	struct device_dma_parameters *dma_parms;
407 
408 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
409 
410 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
411 					     override */
412 	/* arch specific additions */
413 	struct dev_archdata	archdata;
414 
415 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
416 
417 	spinlock_t		devres_lock;
418 	struct list_head	devres_head;
419 
420 	struct klist_node	knode_class;
421 	struct class		*class;
422 	struct attribute_group	**groups;	/* optional groups */
423 
424 	void	(*release)(struct device *dev);
425 };
426 
427 /* Get the wakeup routines, which depend on struct device */
428 #include <linux/pm_wakeup.h>
429 
430 static inline const char *dev_name(const struct device *dev)
431 {
432 	return kobject_name(&dev->kobj);
433 }
434 
435 extern int dev_set_name(struct device *dev, const char *name, ...)
436 			__attribute__((format(printf, 2, 3)));
437 
438 #ifdef CONFIG_NUMA
439 static inline int dev_to_node(struct device *dev)
440 {
441 	return dev->numa_node;
442 }
443 static inline void set_dev_node(struct device *dev, int node)
444 {
445 	dev->numa_node = node;
446 }
447 #else
448 static inline int dev_to_node(struct device *dev)
449 {
450 	return -1;
451 }
452 static inline void set_dev_node(struct device *dev, int node)
453 {
454 }
455 #endif
456 
457 static inline void *dev_get_drvdata(const struct device *dev)
458 {
459 	return dev->driver_data;
460 }
461 
462 static inline void dev_set_drvdata(struct device *dev, void *data)
463 {
464 	dev->driver_data = data;
465 }
466 
467 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
468 {
469 	return dev->kobj.uevent_suppress;
470 }
471 
472 static inline void dev_set_uevent_suppress(struct device *dev, int val)
473 {
474 	dev->kobj.uevent_suppress = val;
475 }
476 
477 static inline int device_is_registered(struct device *dev)
478 {
479 	return dev->kobj.state_in_sysfs;
480 }
481 
482 void driver_init(void);
483 
484 /*
485  * High level routines for use by the bus drivers
486  */
487 extern int __must_check device_register(struct device *dev);
488 extern void device_unregister(struct device *dev);
489 extern void device_initialize(struct device *dev);
490 extern int __must_check device_add(struct device *dev);
491 extern void device_del(struct device *dev);
492 extern int device_for_each_child(struct device *dev, void *data,
493 		     int (*fn)(struct device *dev, void *data));
494 extern struct device *device_find_child(struct device *dev, void *data,
495 				int (*match)(struct device *dev, void *data));
496 extern int device_rename(struct device *dev, char *new_name);
497 extern int device_move(struct device *dev, struct device *new_parent,
498 		       enum dpm_order dpm_order);
499 
500 /*
501  * Root device objects for grouping under /sys/devices
502  */
503 extern struct device *__root_device_register(const char *name,
504 					     struct module *owner);
505 static inline struct device *root_device_register(const char *name)
506 {
507 	return __root_device_register(name, THIS_MODULE);
508 }
509 extern void root_device_unregister(struct device *root);
510 
511 /*
512  * Manual binding of a device to driver. See drivers/base/bus.c
513  * for information on use.
514  */
515 extern int __must_check device_bind_driver(struct device *dev);
516 extern void device_release_driver(struct device *dev);
517 extern int  __must_check device_attach(struct device *dev);
518 extern int __must_check driver_attach(struct device_driver *drv);
519 extern int __must_check device_reprobe(struct device *dev);
520 
521 /*
522  * Easy functions for dynamically creating devices on the fly
523  */
524 extern struct device *device_create_vargs(struct class *cls,
525 					  struct device *parent,
526 					  dev_t devt,
527 					  void *drvdata,
528 					  const char *fmt,
529 					  va_list vargs);
530 extern struct device *device_create(struct class *cls, struct device *parent,
531 				    dev_t devt, void *drvdata,
532 				    const char *fmt, ...)
533 				    __attribute__((format(printf, 5, 6)));
534 extern void device_destroy(struct class *cls, dev_t devt);
535 
536 /*
537  * Platform "fixup" functions - allow the platform to have their say
538  * about devices and actions that the general device layer doesn't
539  * know about.
540  */
541 /* Notify platform of device discovery */
542 extern int (*platform_notify)(struct device *dev);
543 
544 extern int (*platform_notify_remove)(struct device *dev);
545 
546 
547 /**
548  * get_device - atomically increment the reference count for the device.
549  *
550  */
551 extern struct device *get_device(struct device *dev);
552 extern void put_device(struct device *dev);
553 
554 
555 /* drivers/base/power/shutdown.c */
556 extern void device_shutdown(void);
557 
558 /* drivers/base/sys.c */
559 extern void sysdev_shutdown(void);
560 
561 /* debugging and troubleshooting/diagnostic helpers. */
562 extern const char *dev_driver_string(const struct device *dev);
563 #define dev_printk(level, dev, format, arg...)	\
564 	printk(level "%s %s: " format , dev_driver_string(dev) , \
565 	       dev_name(dev) , ## arg)
566 
567 #define dev_emerg(dev, format, arg...)		\
568 	dev_printk(KERN_EMERG , dev , format , ## arg)
569 #define dev_alert(dev, format, arg...)		\
570 	dev_printk(KERN_ALERT , dev , format , ## arg)
571 #define dev_crit(dev, format, arg...)		\
572 	dev_printk(KERN_CRIT , dev , format , ## arg)
573 #define dev_err(dev, format, arg...)		\
574 	dev_printk(KERN_ERR , dev , format , ## arg)
575 #define dev_warn(dev, format, arg...)		\
576 	dev_printk(KERN_WARNING , dev , format , ## arg)
577 #define dev_notice(dev, format, arg...)		\
578 	dev_printk(KERN_NOTICE , dev , format , ## arg)
579 #define dev_info(dev, format, arg...)		\
580 	dev_printk(KERN_INFO , dev , format , ## arg)
581 
582 #if defined(DEBUG)
583 #define dev_dbg(dev, format, arg...)		\
584 	dev_printk(KERN_DEBUG , dev , format , ## arg)
585 #elif defined(CONFIG_DYNAMIC_DEBUG)
586 #define dev_dbg(dev, format, ...) do { \
587 	dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
588 	} while (0)
589 #else
590 #define dev_dbg(dev, format, arg...)		\
591 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
592 #endif
593 
594 #ifdef VERBOSE_DEBUG
595 #define dev_vdbg	dev_dbg
596 #else
597 
598 #define dev_vdbg(dev, format, arg...)		\
599 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
600 #endif
601 
602 /*
603  * dev_WARN() acts like dev_printk(), but with the key difference
604  * of using a WARN/WARN_ON to get the message out, including the
605  * file/line information and a backtrace.
606  */
607 #define dev_WARN(dev, format, arg...) \
608 	WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg);
609 
610 /* Create alias, so I can be autoloaded. */
611 #define MODULE_ALIAS_CHARDEV(major,minor) \
612 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
613 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
614 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
615 #endif /* _DEVICE_H_ */
616