xref: /linux-6.15/include/linux/device.h (revision 40efcb05)
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/compiler.h>
20 #include <linux/types.h>
21 #include <linux/module.h>
22 #include <linux/pm.h>
23 #include <asm/semaphore.h>
24 #include <asm/atomic.h>
25 #include <asm/device.h>
26 
27 #define DEVICE_NAME_SIZE	50
28 #define DEVICE_NAME_HALF	__stringify(20)	/* Less than half to accommodate slop */
29 #define DEVICE_ID_SIZE		32
30 #define BUS_ID_SIZE		KOBJ_NAME_LEN
31 
32 
33 struct device;
34 struct device_driver;
35 struct driver_private;
36 struct class;
37 struct class_device;
38 struct bus_type;
39 struct bus_type_private;
40 
41 struct bus_attribute {
42 	struct attribute	attr;
43 	ssize_t (*show)(struct bus_type *, char * buf);
44 	ssize_t (*store)(struct bus_type *, const char * buf, size_t count);
45 };
46 
47 #define BUS_ATTR(_name,_mode,_show,_store)	\
48 struct bus_attribute bus_attr_##_name = __ATTR(_name,_mode,_show,_store)
49 
50 extern int __must_check bus_create_file(struct bus_type *,
51 					struct bus_attribute *);
52 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
53 
54 struct bus_type {
55 	const char		* name;
56 	struct bus_attribute	* bus_attrs;
57 	struct device_attribute	* dev_attrs;
58 	struct driver_attribute	* drv_attrs;
59 
60 	int		(*match)(struct device * dev, struct device_driver * drv);
61 	int		(*uevent)(struct device *dev, struct kobj_uevent_env *env);
62 	int		(*probe)(struct device * dev);
63 	int		(*remove)(struct device * dev);
64 	void		(*shutdown)(struct device * dev);
65 
66 	int (*suspend)(struct device * dev, pm_message_t state);
67 	int (*suspend_late)(struct device * dev, pm_message_t state);
68 	int (*resume_early)(struct device * dev);
69 	int (*resume)(struct device * dev);
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 *, void *));
83 struct device * bus_find_device(struct bus_type *bus, struct device *start,
84 				void *data, int (*match)(struct device *, void *));
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 /*
91  * Bus notifiers: Get notified of addition/removal of devices
92  * and binding/unbinding of drivers to devices.
93  * In the long run, it should be a replacement for the platform
94  * notify hooks.
95  */
96 struct notifier_block;
97 
98 extern int bus_register_notifier(struct bus_type *bus,
99 				 struct notifier_block *nb);
100 extern int bus_unregister_notifier(struct bus_type *bus,
101 				   struct notifier_block *nb);
102 
103 /* All 4 notifers below get called with the target struct device *
104  * as an argument. Note that those functions are likely to be called
105  * with the device semaphore held in the core, so be careful.
106  */
107 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
108 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device removed */
109 #define BUS_NOTIFY_BOUND_DRIVER		0x00000003 /* driver bound to device */
110 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000004 /* driver about to be
111 						      unbound */
112 
113 extern struct kset *bus_get_kset(struct bus_type *bus);
114 extern struct klist *bus_get_device_klist(struct bus_type *bus);
115 
116 struct device_driver {
117 	const char		*name;
118 	struct bus_type		*bus;
119 
120 	struct module		*owner;
121 	const char 		*mod_name;	/* used for built-in modules */
122 
123 	int	(*probe)	(struct device * dev);
124 	int	(*remove)	(struct device * dev);
125 	void	(*shutdown)	(struct device * dev);
126 	int	(*suspend)	(struct device * dev, pm_message_t state);
127 	int	(*resume)	(struct device * dev);
128 	struct attribute_group **groups;
129 
130 	struct driver_private *p;
131 };
132 
133 
134 extern int __must_check driver_register(struct device_driver * drv);
135 extern void driver_unregister(struct device_driver * drv);
136 
137 extern struct device_driver * get_driver(struct device_driver * drv);
138 extern void put_driver(struct device_driver * drv);
139 extern struct device_driver *driver_find(const char *name, struct bus_type *bus);
140 extern int driver_probe_done(void);
141 
142 /* sysfs interface for exporting driver attributes */
143 
144 struct driver_attribute {
145 	struct attribute	attr;
146 	ssize_t (*show)(struct device_driver *, char * buf);
147 	ssize_t (*store)(struct device_driver *, const char * buf, size_t count);
148 };
149 
150 #define DRIVER_ATTR(_name,_mode,_show,_store)	\
151 struct driver_attribute driver_attr_##_name = __ATTR(_name,_mode,_show,_store)
152 
153 extern int __must_check driver_create_file(struct device_driver *,
154 					struct driver_attribute *);
155 extern void driver_remove_file(struct device_driver *, struct driver_attribute *);
156 
157 extern int __must_check driver_add_kobj(struct device_driver *drv,
158 					struct kobject *kobj,
159 					const char *fmt, ...);
160 
161 extern int __must_check driver_for_each_device(struct device_driver * drv,
162 		struct device *start, void *data,
163 		int (*fn)(struct device *, void *));
164 struct device * driver_find_device(struct device_driver *drv,
165 				   struct device *start, void *data,
166 				   int (*match)(struct device *, void *));
167 
168 /*
169  * device classes
170  */
171 struct class {
172 	const char		* name;
173 	struct module		* owner;
174 
175 	struct kset		subsys;
176 	struct list_head	children;
177 	struct list_head	devices;
178 	struct list_head	interfaces;
179 	struct kset		class_dirs;
180 	struct semaphore	sem;	/* locks both the children and interfaces lists */
181 
182 	struct class_attribute		* class_attrs;
183 	struct class_device_attribute	* class_dev_attrs;
184 	struct device_attribute		* dev_attrs;
185 
186 	int	(*uevent)(struct class_device *dev, struct kobj_uevent_env *env);
187 	int	(*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
188 
189 	void	(*release)(struct class_device *dev);
190 	void	(*class_release)(struct class *class);
191 	void	(*dev_release)(struct device *dev);
192 
193 	int	(*suspend)(struct device *, pm_message_t state);
194 	int	(*resume)(struct device *);
195 };
196 
197 extern int __must_check class_register(struct class *);
198 extern void class_unregister(struct class *);
199 
200 
201 struct class_attribute {
202 	struct attribute	attr;
203 	ssize_t (*show)(struct class *, char * buf);
204 	ssize_t (*store)(struct class *, const char * buf, size_t count);
205 };
206 
207 #define CLASS_ATTR(_name,_mode,_show,_store)			\
208 struct class_attribute class_attr_##_name = __ATTR(_name,_mode,_show,_store)
209 
210 extern int __must_check class_create_file(struct class *,
211 					const struct class_attribute *);
212 extern void class_remove_file(struct class *, const struct class_attribute *);
213 
214 struct class_device_attribute {
215 	struct attribute	attr;
216 	ssize_t (*show)(struct class_device *, char * buf);
217 	ssize_t (*store)(struct class_device *, const char * buf, size_t count);
218 };
219 
220 #define CLASS_DEVICE_ATTR(_name,_mode,_show,_store)		\
221 struct class_device_attribute class_device_attr_##_name = 	\
222 	__ATTR(_name,_mode,_show,_store)
223 
224 extern int __must_check class_device_create_file(struct class_device *,
225 				    const struct class_device_attribute *);
226 
227 /**
228  * struct class_device - class devices
229  * @class: pointer to the parent class for this class device.  This is required.
230  * @devt: for internal use by the driver core only.
231  * @node: for internal use by the driver core only.
232  * @kobj: for internal use by the driver core only.
233  * @groups: optional additional groups to be created
234  * @dev: if set, a symlink to the struct device is created in the sysfs
235  * directory for this struct class device.
236  * @class_data: pointer to whatever you want to store here for this struct
237  * class_device.  Use class_get_devdata() and class_set_devdata() to get and
238  * set this pointer.
239  * @parent: pointer to a struct class_device that is the parent of this struct
240  * class_device.  If NULL, this class_device will show up at the root of the
241  * struct class in sysfs (which is probably what you want to have happen.)
242  * @release: pointer to a release function for this struct class_device.  If
243  * set, this will be called instead of the class specific release function.
244  * Only use this if you want to override the default release function, like
245  * when you are nesting class_device structures.
246  * @uevent: pointer to a uevent function for this struct class_device.  If
247  * set, this will be called instead of the class specific uevent function.
248  * Only use this if you want to override the default uevent function, like
249  * when you are nesting class_device structures.
250  */
251 struct class_device {
252 	struct list_head	node;
253 
254 	struct kobject		kobj;
255 	struct class		* class;	/* required */
256 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
257 	struct device		* dev;		/* not necessary, but nice to have */
258 	void			* class_data;	/* class-specific data */
259 	struct class_device	*parent;	/* parent of this child device, if there is one */
260 	struct attribute_group  ** groups;	/* optional groups */
261 
262 	void	(*release)(struct class_device *dev);
263 	int	(*uevent)(struct class_device *dev, struct kobj_uevent_env *env);
264 	char	class_id[BUS_ID_SIZE];	/* unique to this class */
265 };
266 
267 static inline void *
268 class_get_devdata (struct class_device *dev)
269 {
270 	return dev->class_data;
271 }
272 
273 static inline void
274 class_set_devdata (struct class_device *dev, void *data)
275 {
276 	dev->class_data = data;
277 }
278 
279 
280 extern int __must_check class_device_register(struct class_device *);
281 extern void class_device_unregister(struct class_device *);
282 extern void class_device_initialize(struct class_device *);
283 extern int __must_check class_device_add(struct class_device *);
284 extern void class_device_del(struct class_device *);
285 
286 extern struct class_device * class_device_get(struct class_device *);
287 extern void class_device_put(struct class_device *);
288 
289 extern void class_device_remove_file(struct class_device *,
290 				     const struct class_device_attribute *);
291 extern int __must_check class_device_create_bin_file(struct class_device *,
292 					struct bin_attribute *);
293 extern void class_device_remove_bin_file(struct class_device *,
294 					 struct bin_attribute *);
295 
296 struct class_interface {
297 	struct list_head	node;
298 	struct class		*class;
299 
300 	int (*add)	(struct class_device *, struct class_interface *);
301 	void (*remove)	(struct class_device *, struct class_interface *);
302 	int (*add_dev)		(struct device *, struct class_interface *);
303 	void (*remove_dev)	(struct device *, struct class_interface *);
304 };
305 
306 extern int __must_check class_interface_register(struct class_interface *);
307 extern void class_interface_unregister(struct class_interface *);
308 
309 extern struct class *class_create(struct module *owner, const char *name);
310 extern void class_destroy(struct class *cls);
311 extern struct class_device *class_device_create(struct class *cls,
312 						struct class_device *parent,
313 						dev_t devt,
314 						struct device *device,
315 						const char *fmt, ...)
316 					__attribute__((format(printf,5,6)));
317 extern void class_device_destroy(struct class *cls, dev_t devt);
318 
319 /*
320  * The type of device, "struct device" is embedded in. A class
321  * or bus can contain devices of different types
322  * like "partitions" and "disks", "mouse" and "event".
323  * This identifies the device type and carries type-specific
324  * information, equivalent to the kobj_type of a kobject.
325  * If "name" is specified, the uevent will contain it in
326  * the DEVTYPE variable.
327  */
328 struct device_type {
329 	const char *name;
330 	struct attribute_group **groups;
331 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
332 	void (*release)(struct device *dev);
333 	int (*suspend)(struct device * dev, pm_message_t state);
334 	int (*resume)(struct device * dev);
335 };
336 
337 /* interface for exporting device attributes */
338 struct device_attribute {
339 	struct attribute	attr;
340 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
341 			char *buf);
342 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
343 			 const char *buf, size_t count);
344 };
345 
346 #define DEVICE_ATTR(_name,_mode,_show,_store) \
347 struct device_attribute dev_attr_##_name = __ATTR(_name,_mode,_show,_store)
348 
349 extern int __must_check device_create_file(struct device *device,
350 					struct device_attribute * entry);
351 extern void device_remove_file(struct device * dev, struct device_attribute * attr);
352 extern int __must_check device_create_bin_file(struct device *dev,
353 					       struct bin_attribute *attr);
354 extern void device_remove_bin_file(struct device *dev,
355 				   struct bin_attribute *attr);
356 extern int device_schedule_callback_owner(struct device *dev,
357 		void (*func)(struct device *), struct module *owner);
358 
359 /* This is a macro to avoid include problems with THIS_MODULE */
360 #define device_schedule_callback(dev, func)			\
361 	device_schedule_callback_owner(dev, func, THIS_MODULE)
362 
363 /* device resource management */
364 typedef void (*dr_release_t)(struct device *dev, void *res);
365 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
366 
367 #ifdef CONFIG_DEBUG_DEVRES
368 extern void * __devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
369 			     const char *name);
370 #define devres_alloc(release, size, gfp) \
371 	__devres_alloc(release, size, gfp, #release)
372 #else
373 extern void * devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
374 #endif
375 extern void devres_free(void *res);
376 extern void devres_add(struct device *dev, void *res);
377 extern void * devres_find(struct device *dev, dr_release_t release,
378 			  dr_match_t match, void *match_data);
379 extern void * devres_get(struct device *dev, void *new_res,
380 			 dr_match_t match, void *match_data);
381 extern void * devres_remove(struct device *dev, dr_release_t release,
382 			    dr_match_t match, void *match_data);
383 extern int devres_destroy(struct device *dev, dr_release_t release,
384 			  dr_match_t match, void *match_data);
385 
386 /* devres group */
387 extern void * __must_check devres_open_group(struct device *dev, void *id,
388 					     gfp_t gfp);
389 extern void devres_close_group(struct device *dev, void *id);
390 extern void devres_remove_group(struct device *dev, void *id);
391 extern int devres_release_group(struct device *dev, void *id);
392 
393 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
394 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
395 extern void devm_kfree(struct device *dev, void *p);
396 
397 struct device {
398 	struct klist		klist_children;
399 	struct klist_node	knode_parent;		/* node in sibling list */
400 	struct klist_node	knode_driver;
401 	struct klist_node	knode_bus;
402 	struct device		*parent;
403 
404 	struct kobject kobj;
405 	char	bus_id[BUS_ID_SIZE];	/* position on parent bus */
406 	struct device_type	*type;
407 	unsigned		is_registered:1;
408 	unsigned		uevent_suppress:1;
409 
410 	struct semaphore	sem;	/* semaphore to synchronize calls to
411 					 * its driver.
412 					 */
413 
414 	struct bus_type	* bus;		/* type of bus device is on */
415 	struct device_driver *driver;	/* which driver has allocated this
416 					   device */
417 	void		*driver_data;	/* data private to the driver */
418 	void		*platform_data;	/* Platform specific data, device
419 					   core doesn't touch it */
420 	struct dev_pm_info	power;
421 
422 #ifdef CONFIG_NUMA
423 	int		numa_node;	/* NUMA node this device is close to */
424 #endif
425 	u64		*dma_mask;	/* dma mask (if dma'able device) */
426 	u64		coherent_dma_mask;/* Like dma_mask, but for
427 					     alloc_coherent mappings as
428 					     not all hardware supports
429 					     64 bit addresses for consistent
430 					     allocations such descriptors. */
431 
432 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
433 
434 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
435 					     override */
436 	/* arch specific additions */
437 	struct dev_archdata	archdata;
438 
439 	spinlock_t		devres_lock;
440 	struct list_head	devres_head;
441 
442 	/* class_device migration path */
443 	struct list_head	node;
444 	struct class		*class;
445 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
446 	struct attribute_group	**groups;	/* optional groups */
447 
448 	void	(*release)(struct device * dev);
449 };
450 
451 #ifdef CONFIG_NUMA
452 static inline int dev_to_node(struct device *dev)
453 {
454 	return dev->numa_node;
455 }
456 static inline void set_dev_node(struct device *dev, int node)
457 {
458 	dev->numa_node = node;
459 }
460 #else
461 static inline int dev_to_node(struct device *dev)
462 {
463 	return -1;
464 }
465 static inline void set_dev_node(struct device *dev, int node)
466 {
467 }
468 #endif
469 
470 static inline void *
471 dev_get_drvdata (struct device *dev)
472 {
473 	return dev->driver_data;
474 }
475 
476 static inline void
477 dev_set_drvdata (struct device *dev, void *data)
478 {
479 	dev->driver_data = data;
480 }
481 
482 static inline int device_is_registered(struct device *dev)
483 {
484 	return dev->is_registered;
485 }
486 
487 void driver_init(void);
488 
489 /*
490  * High level routines for use by the bus drivers
491  */
492 extern int __must_check device_register(struct device * dev);
493 extern void device_unregister(struct device * dev);
494 extern void device_initialize(struct device * dev);
495 extern int __must_check device_add(struct device * dev);
496 extern void device_del(struct device * dev);
497 extern int device_for_each_child(struct device *, void *,
498 		     int (*fn)(struct device *, void *));
499 extern struct device *device_find_child(struct device *, void *data,
500 					int (*match)(struct device *, void *));
501 extern int device_rename(struct device *dev, char *new_name);
502 extern int device_move(struct device *dev, struct device *new_parent);
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(struct class *cls, struct device *parent,
518 				    dev_t devt, const char *fmt, ...)
519 				    __attribute__((format(printf,4,5)));
520 extern void device_destroy(struct class *cls, dev_t devt);
521 #ifdef CONFIG_PM_SLEEP
522 extern void destroy_suspended_device(struct class *cls, dev_t devt);
523 #else /* !CONFIG_PM_SLEEP */
524 static inline void destroy_suspended_device(struct class *cls, dev_t devt)
525 {
526 	device_destroy(cls, devt);
527 }
528 #endif /* !CONFIG_PM_SLEEP */
529 
530 /*
531  * Platform "fixup" functions - allow the platform to have their say
532  * about devices and actions that the general device layer doesn't
533  * know about.
534  */
535 /* Notify platform of device discovery */
536 extern int (*platform_notify)(struct device * dev);
537 
538 extern int (*platform_notify_remove)(struct device * dev);
539 
540 
541 /**
542  * get_device - atomically increment the reference count for the device.
543  *
544  */
545 extern struct device * get_device(struct device * dev);
546 extern void put_device(struct device * dev);
547 
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(struct device *dev);
557 #define dev_printk(level, dev, format, arg...)	\
558 	printk(level "%s %s: " format , dev_driver_string(dev) , (dev)->bus_id , ## 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 #ifdef DEBUG
576 #define dev_dbg(dev, format, arg...)		\
577 	dev_printk(KERN_DEBUG , dev , format , ## arg)
578 #else
579 static inline int __attribute__ ((format (printf, 2, 3)))
580 dev_dbg(struct device * dev, const char * fmt, ...)
581 {
582 	return 0;
583 }
584 #endif
585 
586 #ifdef VERBOSE_DEBUG
587 #define dev_vdbg	dev_dbg
588 #else
589 static inline int __attribute__ ((format (printf, 2, 3)))
590 dev_vdbg(struct device * dev, const char * fmt, ...)
591 {
592 	return 0;
593 }
594 #endif
595 
596 /* Create alias, so I can be autoloaded. */
597 #define MODULE_ALIAS_CHARDEV(major,minor) \
598 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
599 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
600 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
601 #endif /* _DEVICE_H_ */
602