xref: /linux-6.15/include/linux/device.h (revision ecba1060)
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 	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 	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 	struct dev_pm_ops *pm;
204 	struct class_private *p;
205 };
206 
207 struct class_dev_iter {
208 	struct klist_iter		ki;
209 	const struct device_type	*type;
210 };
211 
212 extern struct kobject *sysfs_dev_block_kobj;
213 extern struct kobject *sysfs_dev_char_kobj;
214 extern int __must_check __class_register(struct class *class,
215 					 struct lock_class_key *key);
216 extern void class_unregister(struct class *class);
217 
218 /* This is a #define to keep the compiler from merging different
219  * instances of the __key variable */
220 #define class_register(class)			\
221 ({						\
222 	static struct lock_class_key __key;	\
223 	__class_register(class, &__key);	\
224 })
225 
226 extern void class_dev_iter_init(struct class_dev_iter *iter,
227 				struct class *class,
228 				struct device *start,
229 				const struct device_type *type);
230 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
231 extern void class_dev_iter_exit(struct class_dev_iter *iter);
232 
233 extern int class_for_each_device(struct class *class, struct device *start,
234 				 void *data,
235 				 int (*fn)(struct device *dev, void *data));
236 extern struct device *class_find_device(struct class *class,
237 					struct device *start, void *data,
238 					int (*match)(struct device *, void *));
239 
240 struct class_attribute {
241 	struct attribute attr;
242 	ssize_t (*show)(struct class *class, char *buf);
243 	ssize_t (*store)(struct class *class, const char *buf, size_t count);
244 };
245 
246 #define CLASS_ATTR(_name, _mode, _show, _store)			\
247 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
248 
249 extern int __must_check class_create_file(struct class *class,
250 					  const struct class_attribute *attr);
251 extern void class_remove_file(struct class *class,
252 			      const struct class_attribute *attr);
253 
254 struct class_interface {
255 	struct list_head	node;
256 	struct class		*class;
257 
258 	int (*add_dev)		(struct device *, struct class_interface *);
259 	void (*remove_dev)	(struct device *, struct class_interface *);
260 };
261 
262 extern int __must_check class_interface_register(struct class_interface *);
263 extern void class_interface_unregister(struct class_interface *);
264 
265 extern struct class * __must_check __class_create(struct module *owner,
266 						  const char *name,
267 						  struct lock_class_key *key);
268 extern void class_destroy(struct class *cls);
269 
270 /* This is a #define to keep the compiler from merging different
271  * instances of the __key variable */
272 #define class_create(owner, name)		\
273 ({						\
274 	static struct lock_class_key __key;	\
275 	__class_create(owner, name, &__key);	\
276 })
277 
278 /*
279  * The type of device, "struct device" is embedded in. A class
280  * or bus can contain devices of different types
281  * like "partitions" and "disks", "mouse" and "event".
282  * This identifies the device type and carries type-specific
283  * information, equivalent to the kobj_type of a kobject.
284  * If "name" is specified, the uevent will contain it in
285  * the DEVTYPE variable.
286  */
287 struct device_type {
288 	const char *name;
289 	struct attribute_group **groups;
290 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
291 	char *(*nodename)(struct device *dev);
292 	void (*release)(struct device *dev);
293 
294 	struct dev_pm_ops *pm;
295 };
296 
297 /* interface for exporting device attributes */
298 struct device_attribute {
299 	struct attribute	attr;
300 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
301 			char *buf);
302 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
303 			 const char *buf, size_t count);
304 };
305 
306 #define DEVICE_ATTR(_name, _mode, _show, _store) \
307 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
308 
309 extern int __must_check device_create_file(struct device *device,
310 					   struct device_attribute *entry);
311 extern void device_remove_file(struct device *dev,
312 			       struct device_attribute *attr);
313 extern int __must_check device_create_bin_file(struct device *dev,
314 					       struct bin_attribute *attr);
315 extern void device_remove_bin_file(struct device *dev,
316 				   struct bin_attribute *attr);
317 extern int device_schedule_callback_owner(struct device *dev,
318 		void (*func)(struct device *dev), struct module *owner);
319 
320 /* This is a macro to avoid include problems with THIS_MODULE */
321 #define device_schedule_callback(dev, func)			\
322 	device_schedule_callback_owner(dev, func, THIS_MODULE)
323 
324 /* device resource management */
325 typedef void (*dr_release_t)(struct device *dev, void *res);
326 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
327 
328 #ifdef CONFIG_DEBUG_DEVRES
329 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
330 			     const char *name);
331 #define devres_alloc(release, size, gfp) \
332 	__devres_alloc(release, size, gfp, #release)
333 #else
334 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
335 #endif
336 extern void devres_free(void *res);
337 extern void devres_add(struct device *dev, void *res);
338 extern void *devres_find(struct device *dev, dr_release_t release,
339 			 dr_match_t match, void *match_data);
340 extern void *devres_get(struct device *dev, void *new_res,
341 			dr_match_t match, void *match_data);
342 extern void *devres_remove(struct device *dev, dr_release_t release,
343 			   dr_match_t match, void *match_data);
344 extern int devres_destroy(struct device *dev, dr_release_t release,
345 			  dr_match_t match, void *match_data);
346 
347 /* devres group */
348 extern void * __must_check devres_open_group(struct device *dev, void *id,
349 					     gfp_t gfp);
350 extern void devres_close_group(struct device *dev, void *id);
351 extern void devres_remove_group(struct device *dev, void *id);
352 extern int devres_release_group(struct device *dev, void *id);
353 
354 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
355 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
356 extern void devm_kfree(struct device *dev, void *p);
357 
358 struct device_dma_parameters {
359 	/*
360 	 * a low level driver may set these to teach IOMMU code about
361 	 * sg limitations.
362 	 */
363 	unsigned int max_segment_size;
364 	unsigned long segment_boundary_mask;
365 };
366 
367 struct device {
368 	struct device		*parent;
369 
370 	struct device_private	*p;
371 
372 	struct kobject kobj;
373 	const char		*init_name; /* initial name of the device */
374 	struct device_type	*type;
375 
376 	struct semaphore	sem;	/* semaphore to synchronize calls to
377 					 * its driver.
378 					 */
379 
380 	struct bus_type	*bus;		/* type of bus device is on */
381 	struct device_driver *driver;	/* which driver has allocated this
382 					   device */
383 	void		*driver_data;	/* data private to the driver */
384 	void		*platform_data;	/* Platform specific data, device
385 					   core doesn't touch it */
386 	struct dev_pm_info	power;
387 
388 #ifdef CONFIG_NUMA
389 	int		numa_node;	/* NUMA node this device is close to */
390 #endif
391 	u64		*dma_mask;	/* dma mask (if dma'able device) */
392 	u64		coherent_dma_mask;/* Like dma_mask, but for
393 					     alloc_coherent mappings as
394 					     not all hardware supports
395 					     64 bit addresses for consistent
396 					     allocations such descriptors. */
397 
398 	struct device_dma_parameters *dma_parms;
399 
400 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
401 
402 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
403 					     override */
404 	/* arch specific additions */
405 	struct dev_archdata	archdata;
406 
407 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
408 
409 	spinlock_t		devres_lock;
410 	struct list_head	devres_head;
411 
412 	struct klist_node	knode_class;
413 	struct class		*class;
414 	struct attribute_group	**groups;	/* optional groups */
415 
416 	void	(*release)(struct device *dev);
417 };
418 
419 /* Get the wakeup routines, which depend on struct device */
420 #include <linux/pm_wakeup.h>
421 
422 static inline const char *dev_name(const struct device *dev)
423 {
424 	return kobject_name(&dev->kobj);
425 }
426 
427 extern int dev_set_name(struct device *dev, const char *name, ...)
428 			__attribute__((format(printf, 2, 3)));
429 
430 #ifdef CONFIG_NUMA
431 static inline int dev_to_node(struct device *dev)
432 {
433 	return dev->numa_node;
434 }
435 static inline void set_dev_node(struct device *dev, int node)
436 {
437 	dev->numa_node = node;
438 }
439 #else
440 static inline int dev_to_node(struct device *dev)
441 {
442 	return -1;
443 }
444 static inline void set_dev_node(struct device *dev, int node)
445 {
446 }
447 #endif
448 
449 static inline void *dev_get_drvdata(const struct device *dev)
450 {
451 	return dev->driver_data;
452 }
453 
454 static inline void dev_set_drvdata(struct device *dev, void *data)
455 {
456 	dev->driver_data = data;
457 }
458 
459 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
460 {
461 	return dev->kobj.uevent_suppress;
462 }
463 
464 static inline void dev_set_uevent_suppress(struct device *dev, int val)
465 {
466 	dev->kobj.uevent_suppress = val;
467 }
468 
469 static inline int device_is_registered(struct device *dev)
470 {
471 	return dev->kobj.state_in_sysfs;
472 }
473 
474 void driver_init(void);
475 
476 /*
477  * High level routines for use by the bus drivers
478  */
479 extern int __must_check device_register(struct device *dev);
480 extern void device_unregister(struct device *dev);
481 extern void device_initialize(struct device *dev);
482 extern int __must_check device_add(struct device *dev);
483 extern void device_del(struct device *dev);
484 extern int device_for_each_child(struct device *dev, void *data,
485 		     int (*fn)(struct device *dev, void *data));
486 extern struct device *device_find_child(struct device *dev, void *data,
487 				int (*match)(struct device *dev, void *data));
488 extern int device_rename(struct device *dev, char *new_name);
489 extern int device_move(struct device *dev, struct device *new_parent,
490 		       enum dpm_order dpm_order);
491 extern const char *device_get_nodename(struct device *dev, const char **tmp);
492 
493 /*
494  * Root device objects for grouping under /sys/devices
495  */
496 extern struct device *__root_device_register(const char *name,
497 					     struct module *owner);
498 static inline struct device *root_device_register(const char *name)
499 {
500 	return __root_device_register(name, THIS_MODULE);
501 }
502 extern void root_device_unregister(struct device *root);
503 
504 /*
505  * Manual binding of a device to driver. See drivers/base/bus.c
506  * for information on use.
507  */
508 extern int __must_check device_bind_driver(struct device *dev);
509 extern void device_release_driver(struct device *dev);
510 extern int  __must_check device_attach(struct device *dev);
511 extern int __must_check driver_attach(struct device_driver *drv);
512 extern int __must_check device_reprobe(struct device *dev);
513 
514 /*
515  * Easy functions for dynamically creating devices on the fly
516  */
517 extern struct device *device_create_vargs(struct class *cls,
518 					  struct device *parent,
519 					  dev_t devt,
520 					  void *drvdata,
521 					  const char *fmt,
522 					  va_list vargs);
523 extern struct device *device_create(struct class *cls, struct device *parent,
524 				    dev_t devt, void *drvdata,
525 				    const char *fmt, ...)
526 				    __attribute__((format(printf, 5, 6)));
527 extern void device_destroy(struct class *cls, dev_t devt);
528 
529 /*
530  * Platform "fixup" functions - allow the platform to have their say
531  * about devices and actions that the general device layer doesn't
532  * know about.
533  */
534 /* Notify platform of device discovery */
535 extern int (*platform_notify)(struct device *dev);
536 
537 extern int (*platform_notify_remove)(struct device *dev);
538 
539 
540 /**
541  * get_device - atomically increment the reference count for the device.
542  *
543  */
544 extern struct device *get_device(struct device *dev);
545 extern void put_device(struct device *dev);
546 
547 extern void wait_for_device_probe(void);
548 
549 /* drivers/base/power/shutdown.c */
550 extern void device_shutdown(void);
551 
552 /* drivers/base/sys.c */
553 extern void sysdev_shutdown(void);
554 
555 /* debugging and troubleshooting/diagnostic helpers. */
556 extern const char *dev_driver_string(const struct device *dev);
557 #define dev_printk(level, dev, format, arg...)	\
558 	printk(level "%s %s: " format , dev_driver_string(dev) , \
559 	       dev_name(dev) , ## arg)
560 
561 #define dev_emerg(dev, format, arg...)		\
562 	dev_printk(KERN_EMERG , dev , format , ## arg)
563 #define dev_alert(dev, format, arg...)		\
564 	dev_printk(KERN_ALERT , dev , format , ## arg)
565 #define dev_crit(dev, format, arg...)		\
566 	dev_printk(KERN_CRIT , dev , format , ## arg)
567 #define dev_err(dev, format, arg...)		\
568 	dev_printk(KERN_ERR , dev , format , ## arg)
569 #define dev_warn(dev, format, arg...)		\
570 	dev_printk(KERN_WARNING , dev , format , ## arg)
571 #define dev_notice(dev, format, arg...)		\
572 	dev_printk(KERN_NOTICE , dev , format , ## arg)
573 #define dev_info(dev, format, arg...)		\
574 	dev_printk(KERN_INFO , dev , format , ## arg)
575 
576 #if defined(DEBUG)
577 #define dev_dbg(dev, format, arg...)		\
578 	dev_printk(KERN_DEBUG , dev , format , ## arg)
579 #elif defined(CONFIG_DYNAMIC_DEBUG)
580 #define dev_dbg(dev, format, ...) do { \
581 	dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
582 	} while (0)
583 #else
584 #define dev_dbg(dev, format, arg...)		\
585 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
586 #endif
587 
588 #ifdef VERBOSE_DEBUG
589 #define dev_vdbg	dev_dbg
590 #else
591 
592 #define dev_vdbg(dev, format, arg...)		\
593 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
594 #endif
595 
596 /*
597  * dev_WARN() acts like dev_printk(), but with the key difference
598  * of using a WARN/WARN_ON to get the message out, including the
599  * file/line information and a backtrace.
600  */
601 #define dev_WARN(dev, format, arg...) \
602 	WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg);
603 
604 /* Create alias, so I can be autoloaded. */
605 #define MODULE_ALIAS_CHARDEV(major,minor) \
606 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
607 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
608 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
609 #endif /* _DEVICE_H_ */
610