xref: /linux-6.15/include/linux/device.h (revision 2b8232ce)
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 class;
36 struct class_device;
37 struct bus_type;
38 
39 struct bus_attribute {
40 	struct attribute	attr;
41 	ssize_t (*show)(struct bus_type *, char * buf);
42 	ssize_t (*store)(struct bus_type *, 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 module		* owner;
55 
56 	struct kset		subsys;
57 	struct kset		drivers;
58 	struct kset		devices;
59 	struct klist		klist_devices;
60 	struct klist		klist_drivers;
61 
62 	struct blocking_notifier_head bus_notifier;
63 
64 	struct bus_attribute	* bus_attrs;
65 	struct device_attribute	* dev_attrs;
66 	struct driver_attribute	* drv_attrs;
67 
68 	int		(*match)(struct device * dev, struct device_driver * drv);
69 	int		(*uevent)(struct device *dev, struct kobj_uevent_env *env);
70 	int		(*probe)(struct device * dev);
71 	int		(*remove)(struct device * dev);
72 	void		(*shutdown)(struct device * dev);
73 
74 	int (*suspend)(struct device * dev, pm_message_t state);
75 	int (*suspend_late)(struct device * dev, pm_message_t state);
76 	int (*resume_early)(struct device * dev);
77 	int (*resume)(struct device * dev);
78 
79 	unsigned int drivers_autoprobe:1;
80 };
81 
82 extern int __must_check bus_register(struct bus_type * bus);
83 extern void bus_unregister(struct bus_type * bus);
84 
85 extern int __must_check bus_rescan_devices(struct bus_type * bus);
86 
87 /* iterator helpers for buses */
88 
89 int bus_for_each_dev(struct bus_type * bus, struct device * start, void * data,
90 		     int (*fn)(struct device *, void *));
91 struct device * bus_find_device(struct bus_type *bus, struct device *start,
92 				void *data, int (*match)(struct device *, void *));
93 
94 int __must_check bus_for_each_drv(struct bus_type *bus,
95 		struct device_driver *start, void *data,
96 		int (*fn)(struct device_driver *, void *));
97 
98 /*
99  * Bus notifiers: Get notified of addition/removal of devices
100  * and binding/unbinding of drivers to devices.
101  * In the long run, it should be a replacement for the platform
102  * notify hooks.
103  */
104 struct notifier_block;
105 
106 extern int bus_register_notifier(struct bus_type *bus,
107 				 struct notifier_block *nb);
108 extern int bus_unregister_notifier(struct bus_type *bus,
109 				   struct notifier_block *nb);
110 
111 /* All 4 notifers below get called with the target struct device *
112  * as an argument. Note that those functions are likely to be called
113  * with the device semaphore held in the core, so be careful.
114  */
115 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
116 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device removed */
117 #define BUS_NOTIFY_BOUND_DRIVER		0x00000003 /* driver bound to device */
118 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000004 /* driver about to be
119 						      unbound */
120 
121 struct device_driver {
122 	const char		* name;
123 	struct bus_type		* bus;
124 
125 	struct kobject		kobj;
126 	struct klist		klist_devices;
127 	struct klist_node	knode_bus;
128 
129 	struct module		* owner;
130 	const char 		* mod_name;	/* used for built-in modules */
131 	struct module_kobject	* mkobj;
132 
133 	int	(*probe)	(struct device * dev);
134 	int	(*remove)	(struct device * dev);
135 	void	(*shutdown)	(struct device * dev);
136 	int	(*suspend)	(struct device * dev, pm_message_t state);
137 	int	(*resume)	(struct device * dev);
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, struct bus_type *bus);
147 extern int driver_probe_done(void);
148 
149 /* sysfs interface for exporting driver attributes */
150 
151 struct driver_attribute {
152 	struct attribute	attr;
153 	ssize_t (*show)(struct device_driver *, char * buf);
154 	ssize_t (*store)(struct device_driver *, const char * buf, size_t count);
155 };
156 
157 #define DRIVER_ATTR(_name,_mode,_show,_store)	\
158 struct driver_attribute driver_attr_##_name = __ATTR(_name,_mode,_show,_store)
159 
160 extern int __must_check driver_create_file(struct device_driver *,
161 					struct driver_attribute *);
162 extern void driver_remove_file(struct device_driver *, struct driver_attribute *);
163 
164 extern int __must_check driver_for_each_device(struct device_driver * drv,
165 		struct device *start, void *data,
166 		int (*fn)(struct device *, void *));
167 struct device * driver_find_device(struct device_driver *drv,
168 				   struct device *start, void *data,
169 				   int (*match)(struct device *, void *));
170 
171 /*
172  * device classes
173  */
174 struct class {
175 	const char		* name;
176 	struct module		* owner;
177 
178 	struct kset		subsys;
179 	struct list_head	children;
180 	struct list_head	devices;
181 	struct list_head	interfaces;
182 	struct kset		class_dirs;
183 	struct semaphore	sem;	/* locks both the children and interfaces lists */
184 
185 	struct class_attribute		* class_attrs;
186 	struct class_device_attribute	* class_dev_attrs;
187 	struct device_attribute		* dev_attrs;
188 
189 	int	(*uevent)(struct class_device *dev, struct kobj_uevent_env *env);
190 	int	(*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
191 
192 	void	(*release)(struct class_device *dev);
193 	void	(*class_release)(struct class *class);
194 	void	(*dev_release)(struct device *dev);
195 
196 	int	(*suspend)(struct device *, pm_message_t state);
197 	int	(*resume)(struct device *);
198 };
199 
200 extern int __must_check class_register(struct class *);
201 extern void class_unregister(struct class *);
202 
203 
204 struct class_attribute {
205 	struct attribute	attr;
206 	ssize_t (*show)(struct class *, char * buf);
207 	ssize_t (*store)(struct class *, const char * buf, size_t count);
208 };
209 
210 #define CLASS_ATTR(_name,_mode,_show,_store)			\
211 struct class_attribute class_attr_##_name = __ATTR(_name,_mode,_show,_store)
212 
213 extern int __must_check class_create_file(struct class *,
214 					const struct class_attribute *);
215 extern void class_remove_file(struct class *, const struct class_attribute *);
216 
217 struct class_device_attribute {
218 	struct attribute	attr;
219 	ssize_t (*show)(struct class_device *, char * buf);
220 	ssize_t (*store)(struct class_device *, const char * buf, size_t count);
221 };
222 
223 #define CLASS_DEVICE_ATTR(_name,_mode,_show,_store)		\
224 struct class_device_attribute class_device_attr_##_name = 	\
225 	__ATTR(_name,_mode,_show,_store)
226 
227 extern int __must_check class_device_create_file(struct class_device *,
228 				    const struct class_device_attribute *);
229 
230 /**
231  * struct class_device - class devices
232  * @class: pointer to the parent class for this class device.  This is required.
233  * @devt: for internal use by the driver core only.
234  * @node: for internal use by the driver core only.
235  * @kobj: for internal use by the driver core only.
236  * @groups: optional additional groups to be created
237  * @dev: if set, a symlink to the struct device is created in the sysfs
238  * directory for this struct class device.
239  * @class_data: pointer to whatever you want to store here for this struct
240  * class_device.  Use class_get_devdata() and class_set_devdata() to get and
241  * set this pointer.
242  * @parent: pointer to a struct class_device that is the parent of this struct
243  * class_device.  If NULL, this class_device will show up at the root of the
244  * struct class in sysfs (which is probably what you want to have happen.)
245  * @release: pointer to a release function for this struct class_device.  If
246  * set, this will be called instead of the class specific release function.
247  * Only use this if you want to override the default release function, like
248  * when you are nesting class_device structures.
249  * @uevent: pointer to a uevent function for this struct class_device.  If
250  * set, this will be called instead of the class specific uevent function.
251  * Only use this if you want to override the default uevent function, like
252  * when you are nesting class_device structures.
253  */
254 struct class_device {
255 	struct list_head	node;
256 
257 	struct kobject		kobj;
258 	struct class		* class;	/* required */
259 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
260 	struct device		* dev;		/* not necessary, but nice to have */
261 	void			* class_data;	/* class-specific data */
262 	struct class_device	*parent;	/* parent of this child device, if there is one */
263 	struct attribute_group  ** groups;	/* optional groups */
264 
265 	void	(*release)(struct class_device *dev);
266 	int	(*uevent)(struct class_device *dev, struct kobj_uevent_env *env);
267 	char	class_id[BUS_ID_SIZE];	/* unique to this class */
268 };
269 
270 static inline void *
271 class_get_devdata (struct class_device *dev)
272 {
273 	return dev->class_data;
274 }
275 
276 static inline void
277 class_set_devdata (struct class_device *dev, void *data)
278 {
279 	dev->class_data = data;
280 }
281 
282 
283 extern int __must_check class_device_register(struct class_device *);
284 extern void class_device_unregister(struct class_device *);
285 extern void class_device_initialize(struct class_device *);
286 extern int __must_check class_device_add(struct class_device *);
287 extern void class_device_del(struct class_device *);
288 
289 extern struct class_device * class_device_get(struct class_device *);
290 extern void class_device_put(struct class_device *);
291 
292 extern void class_device_remove_file(struct class_device *,
293 				     const struct class_device_attribute *);
294 extern int __must_check class_device_create_bin_file(struct class_device *,
295 					struct bin_attribute *);
296 extern void class_device_remove_bin_file(struct class_device *,
297 					 struct bin_attribute *);
298 
299 struct class_interface {
300 	struct list_head	node;
301 	struct class		*class;
302 
303 	int (*add)	(struct class_device *, struct class_interface *);
304 	void (*remove)	(struct class_device *, struct class_interface *);
305 	int (*add_dev)		(struct device *, struct class_interface *);
306 	void (*remove_dev)	(struct device *, struct class_interface *);
307 };
308 
309 extern int __must_check class_interface_register(struct class_interface *);
310 extern void class_interface_unregister(struct class_interface *);
311 
312 extern struct class *class_create(struct module *owner, const char *name);
313 extern void class_destroy(struct class *cls);
314 extern struct class_device *class_device_create(struct class *cls,
315 						struct class_device *parent,
316 						dev_t devt,
317 						struct device *device,
318 						const char *fmt, ...)
319 					__attribute__((format(printf,5,6)));
320 extern void class_device_destroy(struct class *cls, dev_t devt);
321 
322 /*
323  * The type of device, "struct device" is embedded in. A class
324  * or bus can contain devices of different types
325  * like "partitions" and "disks", "mouse" and "event".
326  * This identifies the device type and carries type-specific
327  * information, equivalent to the kobj_type of a kobject.
328  * If "name" is specified, the uevent will contain it in
329  * the DEVTYPE variable.
330  */
331 struct device_type {
332 	const char *name;
333 	struct attribute_group **groups;
334 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
335 	void (*release)(struct device *dev);
336 	int (*suspend)(struct device * dev, pm_message_t state);
337 	int (*resume)(struct device * dev);
338 };
339 
340 /* interface for exporting device attributes */
341 struct device_attribute {
342 	struct attribute	attr;
343 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
344 			char *buf);
345 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
346 			 const char *buf, size_t count);
347 };
348 
349 #define DEVICE_ATTR(_name,_mode,_show,_store) \
350 struct device_attribute dev_attr_##_name = __ATTR(_name,_mode,_show,_store)
351 
352 extern int __must_check device_create_file(struct device *device,
353 					struct device_attribute * entry);
354 extern void device_remove_file(struct device * dev, struct device_attribute * attr);
355 extern int __must_check device_create_bin_file(struct device *dev,
356 					       struct bin_attribute *attr);
357 extern void device_remove_bin_file(struct device *dev,
358 				   struct bin_attribute *attr);
359 extern int device_schedule_callback_owner(struct device *dev,
360 		void (*func)(struct device *), struct module *owner);
361 
362 /* This is a macro to avoid include problems with THIS_MODULE */
363 #define device_schedule_callback(dev, func)			\
364 	device_schedule_callback_owner(dev, func, THIS_MODULE)
365 
366 /* device resource management */
367 typedef void (*dr_release_t)(struct device *dev, void *res);
368 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
369 
370 #ifdef CONFIG_DEBUG_DEVRES
371 extern void * __devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
372 			     const char *name);
373 #define devres_alloc(release, size, gfp) \
374 	__devres_alloc(release, size, gfp, #release)
375 #else
376 extern void * devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
377 #endif
378 extern void devres_free(void *res);
379 extern void devres_add(struct device *dev, void *res);
380 extern void * devres_find(struct device *dev, dr_release_t release,
381 			  dr_match_t match, void *match_data);
382 extern void * devres_get(struct device *dev, void *new_res,
383 			 dr_match_t match, void *match_data);
384 extern void * devres_remove(struct device *dev, dr_release_t release,
385 			    dr_match_t match, void *match_data);
386 extern int devres_destroy(struct device *dev, dr_release_t release,
387 			  dr_match_t match, void *match_data);
388 
389 /* devres group */
390 extern void * __must_check devres_open_group(struct device *dev, void *id,
391 					     gfp_t gfp);
392 extern void devres_close_group(struct device *dev, void *id);
393 extern void devres_remove_group(struct device *dev, void *id);
394 extern int devres_release_group(struct device *dev, void *id);
395 
396 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
397 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
398 extern void devm_kfree(struct device *dev, void *p);
399 
400 struct device {
401 	struct klist		klist_children;
402 	struct klist_node	knode_parent;		/* node in sibling list */
403 	struct klist_node	knode_driver;
404 	struct klist_node	knode_bus;
405 	struct device		*parent;
406 
407 	struct kobject kobj;
408 	char	bus_id[BUS_ID_SIZE];	/* position on parent bus */
409 	struct device_type	*type;
410 	unsigned		is_registered:1;
411 	unsigned		uevent_suppress:1;
412 
413 	struct semaphore	sem;	/* semaphore to synchronize calls to
414 					 * its driver.
415 					 */
416 
417 	struct bus_type	* bus;		/* type of bus device is on */
418 	struct device_driver *driver;	/* which driver has allocated this
419 					   device */
420 	void		*driver_data;	/* data private to the driver */
421 	void		*platform_data;	/* Platform specific data, device
422 					   core doesn't touch it */
423 	struct dev_pm_info	power;
424 
425 #ifdef CONFIG_NUMA
426 	int		numa_node;	/* NUMA node this device is close to */
427 #endif
428 	u64		*dma_mask;	/* dma mask (if dma'able device) */
429 	u64		coherent_dma_mask;/* Like dma_mask, but for
430 					     alloc_coherent mappings as
431 					     not all hardware supports
432 					     64 bit addresses for consistent
433 					     allocations such descriptors. */
434 
435 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
436 
437 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
438 					     override */
439 	/* arch specific additions */
440 	struct dev_archdata	archdata;
441 
442 	spinlock_t		devres_lock;
443 	struct list_head	devres_head;
444 
445 	/* class_device migration path */
446 	struct list_head	node;
447 	struct class		*class;
448 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
449 	struct attribute_group	**groups;	/* optional groups */
450 
451 	void	(*release)(struct device * dev);
452 };
453 
454 #ifdef CONFIG_NUMA
455 static inline int dev_to_node(struct device *dev)
456 {
457 	return dev->numa_node;
458 }
459 static inline void set_dev_node(struct device *dev, int node)
460 {
461 	dev->numa_node = node;
462 }
463 #else
464 static inline int dev_to_node(struct device *dev)
465 {
466 	return -1;
467 }
468 static inline void set_dev_node(struct device *dev, int node)
469 {
470 }
471 #endif
472 
473 static inline void *
474 dev_get_drvdata (struct device *dev)
475 {
476 	return dev->driver_data;
477 }
478 
479 static inline void
480 dev_set_drvdata (struct device *dev, void *data)
481 {
482 	dev->driver_data = data;
483 }
484 
485 static inline int device_is_registered(struct device *dev)
486 {
487 	return dev->is_registered;
488 }
489 
490 void driver_init(void);
491 
492 /*
493  * High level routines for use by the bus drivers
494  */
495 extern int __must_check device_register(struct device * dev);
496 extern void device_unregister(struct device * dev);
497 extern void device_initialize(struct device * dev);
498 extern int __must_check device_add(struct device * dev);
499 extern void device_del(struct device * dev);
500 extern int device_for_each_child(struct device *, void *,
501 		     int (*fn)(struct device *, void *));
502 extern struct device *device_find_child(struct device *, void *data,
503 					int (*match)(struct device *, void *));
504 extern int device_rename(struct device *dev, char *new_name);
505 extern int device_move(struct device *dev, struct device *new_parent);
506 
507 /*
508  * Manual binding of a device to driver. See drivers/base/bus.c
509  * for information on use.
510  */
511 extern int __must_check device_bind_driver(struct device *dev);
512 extern void device_release_driver(struct device * dev);
513 extern int  __must_check device_attach(struct device * dev);
514 extern int __must_check driver_attach(struct device_driver *drv);
515 extern int __must_check device_reprobe(struct device *dev);
516 
517 /*
518  * Easy functions for dynamically creating devices on the fly
519  */
520 extern struct device *device_create(struct class *cls, struct device *parent,
521 				    dev_t devt, const char *fmt, ...)
522 				    __attribute__((format(printf,4,5)));
523 extern void device_destroy(struct class *cls, dev_t devt);
524 
525 /*
526  * Platform "fixup" functions - allow the platform to have their say
527  * about devices and actions that the general device layer doesn't
528  * know about.
529  */
530 /* Notify platform of device discovery */
531 extern int (*platform_notify)(struct device * dev);
532 
533 extern int (*platform_notify_remove)(struct device * dev);
534 
535 
536 /**
537  * get_device - atomically increment the reference count for the device.
538  *
539  */
540 extern struct device * get_device(struct device * dev);
541 extern void put_device(struct device * dev);
542 
543 
544 /* drivers/base/power/shutdown.c */
545 extern void device_shutdown(void);
546 
547 /* drivers/base/sys.c */
548 extern void sysdev_shutdown(void);
549 
550 
551 /* drivers/base/firmware.c */
552 extern int __must_check firmware_register(struct kset *);
553 extern void firmware_unregister(struct kset *);
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 #ifdef DEBUG
561 #define dev_dbg(dev, format, arg...)		\
562 	dev_printk(KERN_DEBUG , dev , format , ## arg)
563 #else
564 static inline int __attribute__ ((format (printf, 2, 3)))
565 dev_dbg(struct device * dev, const char * fmt, ...)
566 {
567 	return 0;
568 }
569 #endif
570 
571 #ifdef VERBOSE_DEBUG
572 #define dev_vdbg	dev_dbg
573 #else
574 static inline int __attribute__ ((format (printf, 2, 3)))
575 dev_vdbg(struct device * dev, const char * fmt, ...)
576 {
577 	return 0;
578 }
579 #endif
580 
581 #define dev_err(dev, format, arg...)		\
582 	dev_printk(KERN_ERR , dev , format , ## arg)
583 #define dev_info(dev, format, arg...)		\
584 	dev_printk(KERN_INFO , dev , format , ## arg)
585 #define dev_warn(dev, format, arg...)		\
586 	dev_printk(KERN_WARNING , dev , format , ## arg)
587 #define dev_notice(dev, format, arg...)		\
588 	dev_printk(KERN_NOTICE , dev , format , ## arg)
589 
590 /* Create alias, so I can be autoloaded. */
591 #define MODULE_ALIAS_CHARDEV(major,minor) \
592 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
593 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
594 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
595 #endif /* _DEVICE_H_ */
596