xref: /linux-6.15/include/linux/device.h (revision 7fcab099)
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 #define BUS_NOTIFY_UNBOUND_DRIVER	0x00000005 /* driver is unbound
118 						      from the device */
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 	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 
492 /*
493  * Root device objects for grouping under /sys/devices
494  */
495 extern struct device *__root_device_register(const char *name,
496 					     struct module *owner);
497 static inline struct device *root_device_register(const char *name)
498 {
499 	return __root_device_register(name, THIS_MODULE);
500 }
501 extern void root_device_unregister(struct device *root);
502 
503 /*
504  * Manual binding of a device to driver. See drivers/base/bus.c
505  * for information on use.
506  */
507 extern int __must_check device_bind_driver(struct device *dev);
508 extern void device_release_driver(struct device *dev);
509 extern int  __must_check device_attach(struct device *dev);
510 extern int __must_check driver_attach(struct device_driver *drv);
511 extern int __must_check device_reprobe(struct device *dev);
512 
513 /*
514  * Easy functions for dynamically creating devices on the fly
515  */
516 extern struct device *device_create_vargs(struct class *cls,
517 					  struct device *parent,
518 					  dev_t devt,
519 					  void *drvdata,
520 					  const char *fmt,
521 					  va_list vargs);
522 extern struct device *device_create(struct class *cls, struct device *parent,
523 				    dev_t devt, void *drvdata,
524 				    const char *fmt, ...)
525 				    __attribute__((format(printf, 5, 6)));
526 extern void device_destroy(struct class *cls, dev_t devt);
527 
528 /*
529  * Platform "fixup" functions - allow the platform to have their say
530  * about devices and actions that the general device layer doesn't
531  * know about.
532  */
533 /* Notify platform of device discovery */
534 extern int (*platform_notify)(struct device *dev);
535 
536 extern int (*platform_notify_remove)(struct device *dev);
537 
538 
539 /**
540  * get_device - atomically increment the reference count for the device.
541  *
542  */
543 extern struct device *get_device(struct device *dev);
544 extern void put_device(struct device *dev);
545 
546 extern void wait_for_device_probe(void);
547 
548 /* drivers/base/power/shutdown.c */
549 extern void device_shutdown(void);
550 
551 /* drivers/base/sys.c */
552 extern void sysdev_shutdown(void);
553 
554 /* debugging and troubleshooting/diagnostic helpers. */
555 extern const char *dev_driver_string(const struct device *dev);
556 #define dev_printk(level, dev, format, arg...)	\
557 	printk(level "%s %s: " format , dev_driver_string(dev) , \
558 	       dev_name(dev) , ## arg)
559 
560 #define dev_emerg(dev, format, arg...)		\
561 	dev_printk(KERN_EMERG , dev , format , ## arg)
562 #define dev_alert(dev, format, arg...)		\
563 	dev_printk(KERN_ALERT , dev , format , ## arg)
564 #define dev_crit(dev, format, arg...)		\
565 	dev_printk(KERN_CRIT , dev , format , ## arg)
566 #define dev_err(dev, format, arg...)		\
567 	dev_printk(KERN_ERR , dev , format , ## arg)
568 #define dev_warn(dev, format, arg...)		\
569 	dev_printk(KERN_WARNING , dev , format , ## arg)
570 #define dev_notice(dev, format, arg...)		\
571 	dev_printk(KERN_NOTICE , dev , format , ## arg)
572 #define dev_info(dev, format, arg...)		\
573 	dev_printk(KERN_INFO , dev , format , ## arg)
574 
575 #if defined(DEBUG)
576 #define dev_dbg(dev, format, arg...)		\
577 	dev_printk(KERN_DEBUG , dev , format , ## arg)
578 #elif defined(CONFIG_DYNAMIC_DEBUG)
579 #define dev_dbg(dev, format, ...) do { \
580 	dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
581 	} while (0)
582 #else
583 #define dev_dbg(dev, format, arg...)		\
584 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
585 #endif
586 
587 #ifdef VERBOSE_DEBUG
588 #define dev_vdbg	dev_dbg
589 #else
590 
591 #define dev_vdbg(dev, format, arg...)		\
592 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
593 #endif
594 
595 /*
596  * dev_WARN() acts like dev_printk(), but with the key difference
597  * of using a WARN/WARN_ON to get the message out, including the
598  * file/line information and a backtrace.
599  */
600 #define dev_WARN(dev, format, arg...) \
601 	WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg);
602 
603 /* Create alias, so I can be autoloaded. */
604 #define MODULE_ALIAS_CHARDEV(major,minor) \
605 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
606 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
607 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
608 #endif /* _DEVICE_H_ */
609