xref: /linux-6.15/include/linux/device.h (revision 156f5a78)
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 	char *(*nodename)(struct device *dev);
198 
199 	void (*class_release)(struct class *class);
200 	void (*dev_release)(struct device *dev);
201 
202 	int (*suspend)(struct device *dev, pm_message_t state);
203 	int (*resume)(struct device *dev);
204 
205 	struct dev_pm_ops *pm;
206 	struct class_private *p;
207 };
208 
209 struct class_dev_iter {
210 	struct klist_iter		ki;
211 	const struct device_type	*type;
212 };
213 
214 extern struct kobject *sysfs_dev_block_kobj;
215 extern struct kobject *sysfs_dev_char_kobj;
216 extern int __must_check __class_register(struct class *class,
217 					 struct lock_class_key *key);
218 extern void class_unregister(struct class *class);
219 
220 /* This is a #define to keep the compiler from merging different
221  * instances of the __key variable */
222 #define class_register(class)			\
223 ({						\
224 	static struct lock_class_key __key;	\
225 	__class_register(class, &__key);	\
226 })
227 
228 extern void class_dev_iter_init(struct class_dev_iter *iter,
229 				struct class *class,
230 				struct device *start,
231 				const struct device_type *type);
232 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
233 extern void class_dev_iter_exit(struct class_dev_iter *iter);
234 
235 extern int class_for_each_device(struct class *class, struct device *start,
236 				 void *data,
237 				 int (*fn)(struct device *dev, void *data));
238 extern struct device *class_find_device(struct class *class,
239 					struct device *start, void *data,
240 					int (*match)(struct device *, void *));
241 
242 struct class_attribute {
243 	struct attribute attr;
244 	ssize_t (*show)(struct class *class, char *buf);
245 	ssize_t (*store)(struct class *class, const char *buf, size_t count);
246 };
247 
248 #define CLASS_ATTR(_name, _mode, _show, _store)			\
249 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
250 
251 extern int __must_check class_create_file(struct class *class,
252 					  const struct class_attribute *attr);
253 extern void class_remove_file(struct class *class,
254 			      const struct class_attribute *attr);
255 
256 struct class_interface {
257 	struct list_head	node;
258 	struct class		*class;
259 
260 	int (*add_dev)		(struct device *, struct class_interface *);
261 	void (*remove_dev)	(struct device *, struct class_interface *);
262 };
263 
264 extern int __must_check class_interface_register(struct class_interface *);
265 extern void class_interface_unregister(struct class_interface *);
266 
267 extern struct class * __must_check __class_create(struct module *owner,
268 						  const char *name,
269 						  struct lock_class_key *key);
270 extern void class_destroy(struct class *cls);
271 
272 /* This is a #define to keep the compiler from merging different
273  * instances of the __key variable */
274 #define class_create(owner, name)		\
275 ({						\
276 	static struct lock_class_key __key;	\
277 	__class_create(owner, name, &__key);	\
278 })
279 
280 /*
281  * The type of device, "struct device" is embedded in. A class
282  * or bus can contain devices of different types
283  * like "partitions" and "disks", "mouse" and "event".
284  * This identifies the device type and carries type-specific
285  * information, equivalent to the kobj_type of a kobject.
286  * If "name" is specified, the uevent will contain it in
287  * the DEVTYPE variable.
288  */
289 struct device_type {
290 	const char *name;
291 	struct attribute_group **groups;
292 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
293 	char *(*nodename)(struct device *dev);
294 	void (*release)(struct device *dev);
295 
296 	struct dev_pm_ops *pm;
297 };
298 
299 /* interface for exporting device attributes */
300 struct device_attribute {
301 	struct attribute	attr;
302 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
303 			char *buf);
304 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
305 			 const char *buf, size_t count);
306 };
307 
308 #define DEVICE_ATTR(_name, _mode, _show, _store) \
309 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
310 
311 extern int __must_check device_create_file(struct device *device,
312 					   struct device_attribute *entry);
313 extern void device_remove_file(struct device *dev,
314 			       struct device_attribute *attr);
315 extern int __must_check device_create_bin_file(struct device *dev,
316 					       struct bin_attribute *attr);
317 extern void device_remove_bin_file(struct device *dev,
318 				   struct bin_attribute *attr);
319 extern int device_schedule_callback_owner(struct device *dev,
320 		void (*func)(struct device *dev), struct module *owner);
321 
322 /* This is a macro to avoid include problems with THIS_MODULE */
323 #define device_schedule_callback(dev, func)			\
324 	device_schedule_callback_owner(dev, func, THIS_MODULE)
325 
326 /* device resource management */
327 typedef void (*dr_release_t)(struct device *dev, void *res);
328 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
329 
330 #ifdef CONFIG_DEBUG_DEVRES
331 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
332 			     const char *name);
333 #define devres_alloc(release, size, gfp) \
334 	__devres_alloc(release, size, gfp, #release)
335 #else
336 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
337 #endif
338 extern void devres_free(void *res);
339 extern void devres_add(struct device *dev, void *res);
340 extern void *devres_find(struct device *dev, dr_release_t release,
341 			 dr_match_t match, void *match_data);
342 extern void *devres_get(struct device *dev, void *new_res,
343 			dr_match_t match, void *match_data);
344 extern void *devres_remove(struct device *dev, dr_release_t release,
345 			   dr_match_t match, void *match_data);
346 extern int devres_destroy(struct device *dev, dr_release_t release,
347 			  dr_match_t match, void *match_data);
348 
349 /* devres group */
350 extern void * __must_check devres_open_group(struct device *dev, void *id,
351 					     gfp_t gfp);
352 extern void devres_close_group(struct device *dev, void *id);
353 extern void devres_remove_group(struct device *dev, void *id);
354 extern int devres_release_group(struct device *dev, void *id);
355 
356 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
357 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
358 extern void devm_kfree(struct device *dev, void *p);
359 
360 struct device_dma_parameters {
361 	/*
362 	 * a low level driver may set these to teach IOMMU code about
363 	 * sg limitations.
364 	 */
365 	unsigned int max_segment_size;
366 	unsigned long segment_boundary_mask;
367 };
368 
369 struct device {
370 	struct device		*parent;
371 
372 	struct device_private	*p;
373 
374 	struct kobject kobj;
375 	const char		*init_name; /* initial name of the device */
376 	struct device_type	*type;
377 
378 	struct semaphore	sem;	/* semaphore to synchronize calls to
379 					 * its driver.
380 					 */
381 
382 	struct bus_type	*bus;		/* type of bus device is on */
383 	struct device_driver *driver;	/* which driver has allocated this
384 					   device */
385 	void		*driver_data;	/* data private to the driver */
386 	void		*platform_data;	/* Platform specific data, device
387 					   core doesn't touch it */
388 	struct dev_pm_info	power;
389 
390 #ifdef CONFIG_NUMA
391 	int		numa_node;	/* NUMA node this device is close to */
392 #endif
393 	u64		*dma_mask;	/* dma mask (if dma'able device) */
394 	u64		coherent_dma_mask;/* Like dma_mask, but for
395 					     alloc_coherent mappings as
396 					     not all hardware supports
397 					     64 bit addresses for consistent
398 					     allocations such descriptors. */
399 
400 	struct device_dma_parameters *dma_parms;
401 
402 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
403 
404 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
405 					     override */
406 	/* arch specific additions */
407 	struct dev_archdata	archdata;
408 
409 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
410 
411 	spinlock_t		devres_lock;
412 	struct list_head	devres_head;
413 
414 	struct klist_node	knode_class;
415 	struct class		*class;
416 	struct attribute_group	**groups;	/* optional groups */
417 
418 	void	(*release)(struct device *dev);
419 };
420 
421 /* Get the wakeup routines, which depend on struct device */
422 #include <linux/pm_wakeup.h>
423 
424 static inline const char *dev_name(const struct device *dev)
425 {
426 	return kobject_name(&dev->kobj);
427 }
428 
429 extern int dev_set_name(struct device *dev, const char *name, ...)
430 			__attribute__((format(printf, 2, 3)));
431 
432 #ifdef CONFIG_NUMA
433 static inline int dev_to_node(struct device *dev)
434 {
435 	return dev->numa_node;
436 }
437 static inline void set_dev_node(struct device *dev, int node)
438 {
439 	dev->numa_node = node;
440 }
441 #else
442 static inline int dev_to_node(struct device *dev)
443 {
444 	return -1;
445 }
446 static inline void set_dev_node(struct device *dev, int node)
447 {
448 }
449 #endif
450 
451 static inline void *dev_get_drvdata(const struct device *dev)
452 {
453 	return dev->driver_data;
454 }
455 
456 static inline void dev_set_drvdata(struct device *dev, void *data)
457 {
458 	dev->driver_data = data;
459 }
460 
461 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
462 {
463 	return dev->kobj.uevent_suppress;
464 }
465 
466 static inline void dev_set_uevent_suppress(struct device *dev, int val)
467 {
468 	dev->kobj.uevent_suppress = val;
469 }
470 
471 static inline int device_is_registered(struct device *dev)
472 {
473 	return dev->kobj.state_in_sysfs;
474 }
475 
476 void driver_init(void);
477 
478 /*
479  * High level routines for use by the bus drivers
480  */
481 extern int __must_check device_register(struct device *dev);
482 extern void device_unregister(struct device *dev);
483 extern void device_initialize(struct device *dev);
484 extern int __must_check device_add(struct device *dev);
485 extern void device_del(struct device *dev);
486 extern int device_for_each_child(struct device *dev, void *data,
487 		     int (*fn)(struct device *dev, void *data));
488 extern struct device *device_find_child(struct device *dev, void *data,
489 				int (*match)(struct device *dev, void *data));
490 extern int device_rename(struct device *dev, char *new_name);
491 extern int device_move(struct device *dev, struct device *new_parent,
492 		       enum dpm_order dpm_order);
493 extern const char *device_get_nodename(struct device *dev, const char **tmp);
494 
495 /*
496  * Root device objects for grouping under /sys/devices
497  */
498 extern struct device *__root_device_register(const char *name,
499 					     struct module *owner);
500 static inline struct device *root_device_register(const char *name)
501 {
502 	return __root_device_register(name, THIS_MODULE);
503 }
504 extern void root_device_unregister(struct device *root);
505 
506 /*
507  * Manual binding of a device to driver. See drivers/base/bus.c
508  * for information on use.
509  */
510 extern int __must_check device_bind_driver(struct device *dev);
511 extern void device_release_driver(struct device *dev);
512 extern int  __must_check device_attach(struct device *dev);
513 extern int __must_check driver_attach(struct device_driver *drv);
514 extern int __must_check device_reprobe(struct device *dev);
515 
516 /*
517  * Easy functions for dynamically creating devices on the fly
518  */
519 extern struct device *device_create_vargs(struct class *cls,
520 					  struct device *parent,
521 					  dev_t devt,
522 					  void *drvdata,
523 					  const char *fmt,
524 					  va_list vargs);
525 extern struct device *device_create(struct class *cls, struct device *parent,
526 				    dev_t devt, void *drvdata,
527 				    const char *fmt, ...)
528 				    __attribute__((format(printf, 5, 6)));
529 extern void device_destroy(struct class *cls, dev_t devt);
530 
531 /*
532  * Platform "fixup" functions - allow the platform to have their say
533  * about devices and actions that the general device layer doesn't
534  * know about.
535  */
536 /* Notify platform of device discovery */
537 extern int (*platform_notify)(struct device *dev);
538 
539 extern int (*platform_notify_remove)(struct device *dev);
540 
541 
542 /**
543  * get_device - atomically increment the reference count for the device.
544  *
545  */
546 extern struct device *get_device(struct device *dev);
547 extern void put_device(struct device *dev);
548 
549 extern void wait_for_device_probe(void);
550 
551 /* drivers/base/power/shutdown.c */
552 extern void device_shutdown(void);
553 
554 /* drivers/base/sys.c */
555 extern void sysdev_shutdown(void);
556 
557 /* debugging and troubleshooting/diagnostic helpers. */
558 extern const char *dev_driver_string(const struct device *dev);
559 #define dev_printk(level, dev, format, arg...)	\
560 	printk(level "%s %s: " format , dev_driver_string(dev) , \
561 	       dev_name(dev) , ## arg)
562 
563 #define dev_emerg(dev, format, arg...)		\
564 	dev_printk(KERN_EMERG , dev , format , ## arg)
565 #define dev_alert(dev, format, arg...)		\
566 	dev_printk(KERN_ALERT , dev , format , ## arg)
567 #define dev_crit(dev, format, arg...)		\
568 	dev_printk(KERN_CRIT , dev , format , ## arg)
569 #define dev_err(dev, format, arg...)		\
570 	dev_printk(KERN_ERR , dev , format , ## arg)
571 #define dev_warn(dev, format, arg...)		\
572 	dev_printk(KERN_WARNING , dev , format , ## arg)
573 #define dev_notice(dev, format, arg...)		\
574 	dev_printk(KERN_NOTICE , dev , format , ## arg)
575 #define dev_info(dev, format, arg...)		\
576 	dev_printk(KERN_INFO , dev , format , ## arg)
577 
578 #if defined(DEBUG)
579 #define dev_dbg(dev, format, arg...)		\
580 	dev_printk(KERN_DEBUG , dev , format , ## arg)
581 #elif defined(CONFIG_DYNAMIC_DEBUG)
582 #define dev_dbg(dev, format, ...) do { \
583 	dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
584 	} while (0)
585 #else
586 #define dev_dbg(dev, format, arg...)		\
587 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
588 #endif
589 
590 #ifdef VERBOSE_DEBUG
591 #define dev_vdbg	dev_dbg
592 #else
593 
594 #define dev_vdbg(dev, format, arg...)		\
595 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
596 #endif
597 
598 /*
599  * dev_WARN() acts like dev_printk(), but with the key difference
600  * of using a WARN/WARN_ON to get the message out, including the
601  * file/line information and a backtrace.
602  */
603 #define dev_WARN(dev, format, arg...) \
604 	WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg);
605 
606 /* Create alias, so I can be autoloaded. */
607 #define MODULE_ALIAS_CHARDEV(major,minor) \
608 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
609 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
610 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
611 #endif /* _DEVICE_H_ */
612