xref: /linux-6.15/include/linux/device.h (revision 384740dc)
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_driver;
32 struct driver_private;
33 struct class;
34 struct class_private;
35 struct bus_type;
36 struct bus_type_private;
37 
38 struct bus_attribute {
39 	struct attribute	attr;
40 	ssize_t (*show)(struct bus_type *bus, char *buf);
41 	ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
42 };
43 
44 #define BUS_ATTR(_name, _mode, _show, _store)	\
45 struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)
46 
47 extern int __must_check bus_create_file(struct bus_type *,
48 					struct bus_attribute *);
49 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
50 
51 struct bus_type {
52 	const char		*name;
53 	struct bus_attribute	*bus_attrs;
54 	struct device_attribute	*dev_attrs;
55 	struct driver_attribute	*drv_attrs;
56 
57 	int (*match)(struct device *dev, struct device_driver *drv);
58 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
59 	int (*probe)(struct device *dev);
60 	int (*remove)(struct device *dev);
61 	void (*shutdown)(struct device *dev);
62 
63 	int (*suspend)(struct device *dev, pm_message_t state);
64 	int (*suspend_late)(struct device *dev, pm_message_t state);
65 	int (*resume_early)(struct device *dev);
66 	int (*resume)(struct device *dev);
67 
68 	struct pm_ext_ops *pm;
69 
70 	struct bus_type_private *p;
71 };
72 
73 extern int __must_check bus_register(struct bus_type *bus);
74 extern void bus_unregister(struct bus_type *bus);
75 
76 extern int __must_check bus_rescan_devices(struct bus_type *bus);
77 
78 /* iterator helpers for buses */
79 
80 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
81 		     int (*fn)(struct device *dev, void *data));
82 struct device *bus_find_device(struct bus_type *bus, struct device *start,
83 			       void *data,
84 			       int (*match)(struct device *dev, void *data));
85 struct device *bus_find_device_by_name(struct bus_type *bus,
86 				       struct device *start,
87 				       const char *name);
88 
89 int __must_check bus_for_each_drv(struct bus_type *bus,
90 				  struct device_driver *start, void *data,
91 				  int (*fn)(struct device_driver *, void *));
92 
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 
116 extern struct kset *bus_get_kset(struct bus_type *bus);
117 extern struct klist *bus_get_device_klist(struct bus_type *bus);
118 
119 struct device_driver {
120 	const char		*name;
121 	struct bus_type		*bus;
122 
123 	struct module		*owner;
124 	const char 		*mod_name;	/* used for built-in modules */
125 
126 	int (*probe) (struct device *dev);
127 	int (*remove) (struct device *dev);
128 	void (*shutdown) (struct device *dev);
129 	int (*suspend) (struct device *dev, pm_message_t state);
130 	int (*resume) (struct device *dev);
131 	struct attribute_group **groups;
132 
133 	struct pm_ops *pm;
134 
135 	struct driver_private *p;
136 };
137 
138 
139 extern int __must_check driver_register(struct device_driver *drv);
140 extern void driver_unregister(struct device_driver *drv);
141 
142 extern struct device_driver *get_driver(struct device_driver *drv);
143 extern void put_driver(struct device_driver *drv);
144 extern struct device_driver *driver_find(const char *name,
145 					 struct bus_type *bus);
146 extern int driver_probe_done(void);
147 
148 /* sysfs interface for exporting driver attributes */
149 
150 struct driver_attribute {
151 	struct attribute attr;
152 	ssize_t (*show)(struct device_driver *driver, char *buf);
153 	ssize_t (*store)(struct device_driver *driver, const char *buf,
154 			 size_t count);
155 };
156 
157 #define DRIVER_ATTR(_name, _mode, _show, _store)	\
158 struct driver_attribute driver_attr_##_name =		\
159 	__ATTR(_name, _mode, _show, _store)
160 
161 extern int __must_check driver_create_file(struct device_driver *driver,
162 					   struct driver_attribute *attr);
163 extern void driver_remove_file(struct device_driver *driver,
164 			       struct driver_attribute *attr);
165 
166 extern int __must_check driver_add_kobj(struct device_driver *drv,
167 					struct kobject *kobj,
168 					const char *fmt, ...);
169 
170 extern int __must_check driver_for_each_device(struct device_driver *drv,
171 					       struct device *start,
172 					       void *data,
173 					       int (*fn)(struct device *dev,
174 							 void *));
175 struct device *driver_find_device(struct device_driver *drv,
176 				  struct device *start, void *data,
177 				  int (*match)(struct device *dev, void *data));
178 
179 /*
180  * device classes
181  */
182 struct class {
183 	const char		*name;
184 	struct module		*owner;
185 
186 	struct class_attribute		*class_attrs;
187 	struct device_attribute		*dev_attrs;
188 	struct kobject			*dev_kobj;
189 
190 	int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
191 
192 	void (*class_release)(struct class *class);
193 	void (*dev_release)(struct device *dev);
194 
195 	int (*suspend)(struct device *dev, pm_message_t state);
196 	int (*resume)(struct device *dev);
197 
198 	struct pm_ops *pm;
199 	struct class_private *p;
200 };
201 
202 struct class_dev_iter {
203 	struct klist_iter		ki;
204 	const struct device_type	*type;
205 };
206 
207 extern struct kobject *sysfs_dev_block_kobj;
208 extern struct kobject *sysfs_dev_char_kobj;
209 extern int __must_check __class_register(struct class *class,
210 					 struct lock_class_key *key);
211 extern void class_unregister(struct class *class);
212 
213 /* This is a #define to keep the compiler from merging different
214  * instances of the __key variable */
215 #define class_register(class)			\
216 ({						\
217 	static struct lock_class_key __key;	\
218 	__class_register(class, &__key);	\
219 })
220 
221 extern void class_dev_iter_init(struct class_dev_iter *iter,
222 				struct class *class,
223 				struct device *start,
224 				const struct device_type *type);
225 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
226 extern void class_dev_iter_exit(struct class_dev_iter *iter);
227 
228 extern int class_for_each_device(struct class *class, struct device *start,
229 				 void *data,
230 				 int (*fn)(struct device *dev, void *data));
231 extern struct device *class_find_device(struct class *class,
232 					struct device *start, void *data,
233 					int (*match)(struct device *, void *));
234 
235 struct class_attribute {
236 	struct attribute attr;
237 	ssize_t (*show)(struct class *class, char *buf);
238 	ssize_t (*store)(struct class *class, const char *buf, size_t count);
239 };
240 
241 #define CLASS_ATTR(_name, _mode, _show, _store)			\
242 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
243 
244 extern int __must_check class_create_file(struct class *class,
245 					  const struct class_attribute *attr);
246 extern void class_remove_file(struct class *class,
247 			      const struct class_attribute *attr);
248 
249 struct class_interface {
250 	struct list_head	node;
251 	struct class		*class;
252 
253 	int (*add_dev)		(struct device *, struct class_interface *);
254 	void (*remove_dev)	(struct device *, struct class_interface *);
255 };
256 
257 extern int __must_check class_interface_register(struct class_interface *);
258 extern void class_interface_unregister(struct class_interface *);
259 
260 extern struct class * __must_check __class_create(struct module *owner,
261 						  const char *name,
262 						  struct lock_class_key *key);
263 extern void class_destroy(struct class *cls);
264 
265 /* This is a #define to keep the compiler from merging different
266  * instances of the __key variable */
267 #define class_create(owner, name)		\
268 ({						\
269 	static struct lock_class_key __key;	\
270 	__class_create(owner, name, &__key);	\
271 })
272 
273 /*
274  * The type of device, "struct device" is embedded in. A class
275  * or bus can contain devices of different types
276  * like "partitions" and "disks", "mouse" and "event".
277  * This identifies the device type and carries type-specific
278  * information, equivalent to the kobj_type of a kobject.
279  * If "name" is specified, the uevent will contain it in
280  * the DEVTYPE variable.
281  */
282 struct device_type {
283 	const char *name;
284 	struct attribute_group **groups;
285 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
286 	void (*release)(struct device *dev);
287 
288 	int (*suspend)(struct device *dev, pm_message_t state);
289 	int (*resume)(struct device *dev);
290 
291 	struct pm_ops *pm;
292 };
293 
294 /* interface for exporting device attributes */
295 struct device_attribute {
296 	struct attribute	attr;
297 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
298 			char *buf);
299 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
300 			 const char *buf, size_t count);
301 };
302 
303 #define DEVICE_ATTR(_name, _mode, _show, _store) \
304 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
305 
306 extern int __must_check device_create_file(struct device *device,
307 					   struct device_attribute *entry);
308 extern void device_remove_file(struct device *dev,
309 			       struct device_attribute *attr);
310 extern int __must_check device_create_bin_file(struct device *dev,
311 					       struct bin_attribute *attr);
312 extern void device_remove_bin_file(struct device *dev,
313 				   struct bin_attribute *attr);
314 extern int device_schedule_callback_owner(struct device *dev,
315 		void (*func)(struct device *dev), struct module *owner);
316 
317 /* This is a macro to avoid include problems with THIS_MODULE */
318 #define device_schedule_callback(dev, func)			\
319 	device_schedule_callback_owner(dev, func, THIS_MODULE)
320 
321 /* device resource management */
322 typedef void (*dr_release_t)(struct device *dev, void *res);
323 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
324 
325 #ifdef CONFIG_DEBUG_DEVRES
326 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
327 			     const char *name);
328 #define devres_alloc(release, size, gfp) \
329 	__devres_alloc(release, size, gfp, #release)
330 #else
331 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
332 #endif
333 extern void devres_free(void *res);
334 extern void devres_add(struct device *dev, void *res);
335 extern void *devres_find(struct device *dev, dr_release_t release,
336 			 dr_match_t match, void *match_data);
337 extern void *devres_get(struct device *dev, void *new_res,
338 			dr_match_t match, void *match_data);
339 extern void *devres_remove(struct device *dev, dr_release_t release,
340 			   dr_match_t match, void *match_data);
341 extern int devres_destroy(struct device *dev, dr_release_t release,
342 			  dr_match_t match, void *match_data);
343 
344 /* devres group */
345 extern void * __must_check devres_open_group(struct device *dev, void *id,
346 					     gfp_t gfp);
347 extern void devres_close_group(struct device *dev, void *id);
348 extern void devres_remove_group(struct device *dev, void *id);
349 extern int devres_release_group(struct device *dev, void *id);
350 
351 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
352 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
353 extern void devm_kfree(struct device *dev, void *p);
354 
355 struct device_dma_parameters {
356 	/*
357 	 * a low level driver may set these to teach IOMMU code about
358 	 * sg limitations.
359 	 */
360 	unsigned int max_segment_size;
361 	unsigned long segment_boundary_mask;
362 };
363 
364 struct device {
365 	struct klist		klist_children;
366 	struct klist_node	knode_parent;	/* node in sibling list */
367 	struct klist_node	knode_driver;
368 	struct klist_node	knode_bus;
369 	struct device		*parent;
370 
371 	struct kobject kobj;
372 	char	bus_id[BUS_ID_SIZE];	/* position on parent bus */
373 	const char		*init_name; /* initial name of the device */
374 	struct device_type	*type;
375 	unsigned		uevent_suppress:1;
376 
377 	struct semaphore	sem;	/* semaphore to synchronize calls to
378 					 * its driver.
379 					 */
380 
381 	struct bus_type	*bus;		/* type of bus device is on */
382 	struct device_driver *driver;	/* which driver has allocated this
383 					   device */
384 	void		*driver_data;	/* data private to the driver */
385 	void		*platform_data;	/* Platform specific data, device
386 					   core doesn't touch it */
387 	struct dev_pm_info	power;
388 
389 #ifdef CONFIG_NUMA
390 	int		numa_node;	/* NUMA node this device is close to */
391 #endif
392 	u64		*dma_mask;	/* dma mask (if dma'able device) */
393 	u64		coherent_dma_mask;/* Like dma_mask, but for
394 					     alloc_coherent mappings as
395 					     not all hardware supports
396 					     64 bit addresses for consistent
397 					     allocations such descriptors. */
398 
399 	struct device_dma_parameters *dma_parms;
400 
401 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
402 
403 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
404 					     override */
405 	/* arch specific additions */
406 	struct dev_archdata	archdata;
407 
408 	spinlock_t		devres_lock;
409 	struct list_head	devres_head;
410 
411 	struct klist_node	knode_class;
412 	struct class		*class;
413 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
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 	/* will be changed into kobject_name(&dev->kobj) in the near future */
425 	return dev->bus_id;
426 }
427 
428 extern int dev_set_name(struct device *dev, const char *name, ...)
429 			__attribute__((format(printf, 2, 3)));
430 
431 #ifdef CONFIG_NUMA
432 static inline int dev_to_node(struct device *dev)
433 {
434 	return dev->numa_node;
435 }
436 static inline void set_dev_node(struct device *dev, int node)
437 {
438 	dev->numa_node = node;
439 }
440 #else
441 static inline int dev_to_node(struct device *dev)
442 {
443 	return -1;
444 }
445 static inline void set_dev_node(struct device *dev, int node)
446 {
447 }
448 #endif
449 
450 static inline void *dev_get_drvdata(struct device *dev)
451 {
452 	return dev->driver_data;
453 }
454 
455 static inline void dev_set_drvdata(struct device *dev, void *data)
456 {
457 	dev->driver_data = data;
458 }
459 
460 static inline int device_is_registered(struct device *dev)
461 {
462 	return dev->kobj.state_in_sysfs;
463 }
464 
465 void driver_init(void);
466 
467 /*
468  * High level routines for use by the bus drivers
469  */
470 extern int __must_check device_register(struct device *dev);
471 extern void device_unregister(struct device *dev);
472 extern void device_initialize(struct device *dev);
473 extern int __must_check device_add(struct device *dev);
474 extern void device_del(struct device *dev);
475 extern int device_for_each_child(struct device *dev, void *data,
476 		     int (*fn)(struct device *dev, void *data));
477 extern struct device *device_find_child(struct device *dev, void *data,
478 				int (*match)(struct device *dev, void *data));
479 extern int device_rename(struct device *dev, char *new_name);
480 extern int device_move(struct device *dev, struct device *new_parent);
481 
482 /*
483  * Manual binding of a device to driver. See drivers/base/bus.c
484  * for information on use.
485  */
486 extern int __must_check device_bind_driver(struct device *dev);
487 extern void device_release_driver(struct device *dev);
488 extern int  __must_check device_attach(struct device *dev);
489 extern int __must_check driver_attach(struct device_driver *drv);
490 extern int __must_check device_reprobe(struct device *dev);
491 
492 /*
493  * Easy functions for dynamically creating devices on the fly
494  */
495 extern struct device *device_create_vargs(struct class *cls,
496 					  struct device *parent,
497 					  dev_t devt,
498 					  void *drvdata,
499 					  const char *fmt,
500 					  va_list vargs);
501 extern struct device *device_create(struct class *cls, struct device *parent,
502 				    dev_t devt, void *drvdata,
503 				    const char *fmt, ...)
504 				    __attribute__((format(printf, 5, 6)));
505 #define device_create_drvdata	device_create
506 extern void device_destroy(struct class *cls, dev_t devt);
507 
508 /*
509  * Platform "fixup" functions - allow the platform to have their say
510  * about devices and actions that the general device layer doesn't
511  * know about.
512  */
513 /* Notify platform of device discovery */
514 extern int (*platform_notify)(struct device *dev);
515 
516 extern int (*platform_notify_remove)(struct device *dev);
517 
518 
519 /**
520  * get_device - atomically increment the reference count for the device.
521  *
522  */
523 extern struct device *get_device(struct device *dev);
524 extern void put_device(struct device *dev);
525 
526 
527 /* drivers/base/power/shutdown.c */
528 extern void device_shutdown(void);
529 
530 /* drivers/base/sys.c */
531 extern void sysdev_shutdown(void);
532 
533 /* debugging and troubleshooting/diagnostic helpers. */
534 extern const char *dev_driver_string(const struct device *dev);
535 #define dev_printk(level, dev, format, arg...)	\
536 	printk(level "%s %s: " format , dev_driver_string(dev) , \
537 	       dev_name(dev) , ## arg)
538 
539 #define dev_emerg(dev, format, arg...)		\
540 	dev_printk(KERN_EMERG , dev , format , ## arg)
541 #define dev_alert(dev, format, arg...)		\
542 	dev_printk(KERN_ALERT , dev , format , ## arg)
543 #define dev_crit(dev, format, arg...)		\
544 	dev_printk(KERN_CRIT , dev , format , ## arg)
545 #define dev_err(dev, format, arg...)		\
546 	dev_printk(KERN_ERR , dev , format , ## arg)
547 #define dev_warn(dev, format, arg...)		\
548 	dev_printk(KERN_WARNING , dev , format , ## arg)
549 #define dev_notice(dev, format, arg...)		\
550 	dev_printk(KERN_NOTICE , dev , format , ## arg)
551 #define dev_info(dev, format, arg...)		\
552 	dev_printk(KERN_INFO , dev , format , ## arg)
553 
554 #ifdef DEBUG
555 #define dev_dbg(dev, format, arg...)		\
556 	dev_printk(KERN_DEBUG , dev , format , ## arg)
557 #else
558 #define dev_dbg(dev, format, arg...)		\
559 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
560 #endif
561 
562 #ifdef VERBOSE_DEBUG
563 #define dev_vdbg	dev_dbg
564 #else
565 
566 #define dev_vdbg(dev, format, arg...)		\
567 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
568 #endif
569 
570 /* Create alias, so I can be autoloaded. */
571 #define MODULE_ALIAS_CHARDEV(major,minor) \
572 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
573 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
574 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
575 #endif /* _DEVICE_H_ */
576