xref: /linux-6.15/include/linux/device.h (revision ba6e8564)
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 
38 struct bus_type {
39 	const char		* name;
40 
41 	struct subsystem	subsys;
42 	struct kset		drivers;
43 	struct kset		devices;
44 	struct klist		klist_devices;
45 	struct klist		klist_drivers;
46 
47 	struct blocking_notifier_head bus_notifier;
48 
49 	struct bus_attribute	* bus_attrs;
50 	struct device_attribute	* dev_attrs;
51 	struct driver_attribute	* drv_attrs;
52 
53 	int		(*match)(struct device * dev, struct device_driver * drv);
54 	int		(*uevent)(struct device *dev, char **envp,
55 				  int num_envp, char *buffer, int buffer_size);
56 	int		(*probe)(struct device * dev);
57 	int		(*remove)(struct device * dev);
58 	void		(*shutdown)(struct device * dev);
59 
60 	int (*suspend)(struct device * dev, pm_message_t state);
61 	int (*suspend_late)(struct device * dev, pm_message_t state);
62 	int (*resume_early)(struct device * dev);
63 	int (*resume)(struct device * dev);
64 };
65 
66 extern int __must_check bus_register(struct bus_type * bus);
67 extern void bus_unregister(struct bus_type * bus);
68 
69 extern int __must_check bus_rescan_devices(struct bus_type * bus);
70 
71 /* iterator helpers for buses */
72 
73 int bus_for_each_dev(struct bus_type * bus, struct device * start, void * data,
74 		     int (*fn)(struct device *, void *));
75 struct device * bus_find_device(struct bus_type *bus, struct device *start,
76 				void *data, int (*match)(struct device *, void *));
77 
78 int __must_check bus_for_each_drv(struct bus_type *bus,
79 		struct device_driver *start, void *data,
80 		int (*fn)(struct device_driver *, void *));
81 
82 /*
83  * Bus notifiers: Get notified of addition/removal of devices
84  * and binding/unbinding of drivers to devices.
85  * In the long run, it should be a replacement for the platform
86  * notify hooks.
87  */
88 struct notifier_block;
89 
90 extern int bus_register_notifier(struct bus_type *bus,
91 				 struct notifier_block *nb);
92 extern int bus_unregister_notifier(struct bus_type *bus,
93 				   struct notifier_block *nb);
94 
95 /* All 4 notifers below get called with the target struct device *
96  * as an argument. Note that those functions are likely to be called
97  * with the device semaphore held in the core, so be careful.
98  */
99 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
100 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device removed */
101 #define BUS_NOTIFY_BOUND_DRIVER		0x00000003 /* driver bound to device */
102 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000004 /* driver about to be
103 						      unbound */
104 
105 /* sysfs interface for exporting bus attributes */
106 
107 struct bus_attribute {
108 	struct attribute	attr;
109 	ssize_t (*show)(struct bus_type *, char * buf);
110 	ssize_t (*store)(struct bus_type *, const char * buf, size_t count);
111 };
112 
113 #define BUS_ATTR(_name,_mode,_show,_store)	\
114 struct bus_attribute bus_attr_##_name = __ATTR(_name,_mode,_show,_store)
115 
116 extern int __must_check bus_create_file(struct bus_type *,
117 					struct bus_attribute *);
118 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
119 
120 struct device_driver {
121 	const char		* name;
122 	struct bus_type		* bus;
123 
124 	struct completion	unloaded;
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 	unsigned int multithread_probe:1;
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, struct bus_type *bus);
149 extern int driver_probe_done(void);
150 
151 /* sysfs interface for exporting driver attributes */
152 
153 struct driver_attribute {
154 	struct attribute	attr;
155 	ssize_t (*show)(struct device_driver *, char * buf);
156 	ssize_t (*store)(struct device_driver *, const char * buf, size_t count);
157 };
158 
159 #define DRIVER_ATTR(_name,_mode,_show,_store)	\
160 struct driver_attribute driver_attr_##_name = __ATTR(_name,_mode,_show,_store)
161 
162 extern int __must_check driver_create_file(struct device_driver *,
163 					struct driver_attribute *);
164 extern void driver_remove_file(struct device_driver *, struct driver_attribute *);
165 
166 extern int __must_check driver_for_each_device(struct device_driver * drv,
167 		struct device *start, void *data,
168 		int (*fn)(struct device *, void *));
169 struct device * driver_find_device(struct device_driver *drv,
170 				   struct device *start, void *data,
171 				   int (*match)(struct device *, void *));
172 
173 /*
174  * device classes
175  */
176 struct class {
177 	const char		* name;
178 	struct module		* owner;
179 
180 	struct subsystem	subsys;
181 	struct list_head	children;
182 	struct list_head	devices;
183 	struct list_head	interfaces;
184 	struct semaphore	sem;	/* locks both the children and interfaces lists */
185 
186 	struct kobject		*virtual_dir;
187 
188 	struct class_attribute		* class_attrs;
189 	struct class_device_attribute	* class_dev_attrs;
190 	struct device_attribute		* dev_attrs;
191 
192 	int	(*uevent)(struct class_device *dev, char **envp,
193 			   int num_envp, char *buffer, int buffer_size);
194 	int	(*dev_uevent)(struct device *dev, char **envp, int num_envp,
195 				char *buffer, int buffer_size);
196 
197 	void	(*release)(struct class_device *dev);
198 	void	(*class_release)(struct class *class);
199 	void	(*dev_release)(struct device *dev);
200 
201 	int	(*suspend)(struct device *, pm_message_t state);
202 	int	(*resume)(struct device *);
203 };
204 
205 extern int __must_check class_register(struct class *);
206 extern void class_unregister(struct class *);
207 
208 
209 struct class_attribute {
210 	struct attribute	attr;
211 	ssize_t (*show)(struct class *, char * buf);
212 	ssize_t (*store)(struct class *, const char * buf, size_t count);
213 };
214 
215 #define CLASS_ATTR(_name,_mode,_show,_store)			\
216 struct class_attribute class_attr_##_name = __ATTR(_name,_mode,_show,_store)
217 
218 extern int __must_check class_create_file(struct class *,
219 					const struct class_attribute *);
220 extern void class_remove_file(struct class *, const struct class_attribute *);
221 
222 struct class_device_attribute {
223 	struct attribute	attr;
224 	ssize_t (*show)(struct class_device *, char * buf);
225 	ssize_t (*store)(struct class_device *, const char * buf, size_t count);
226 };
227 
228 #define CLASS_DEVICE_ATTR(_name,_mode,_show,_store)		\
229 struct class_device_attribute class_device_attr_##_name = 	\
230 	__ATTR(_name,_mode,_show,_store)
231 
232 extern int __must_check class_device_create_file(struct class_device *,
233 				    const struct class_device_attribute *);
234 
235 /**
236  * struct class_device - class devices
237  * @class: pointer to the parent class for this class device.  This is required.
238  * @devt: for internal use by the driver core only.
239  * @node: for internal use by the driver core only.
240  * @kobj: for internal use by the driver core only.
241  * @devt_attr: for internal use by the driver core only.
242  * @groups: optional additional groups to be created
243  * @dev: if set, a symlink to the struct device is created in the sysfs
244  * directory for this struct class device.
245  * @class_data: pointer to whatever you want to store here for this struct
246  * class_device.  Use class_get_devdata() and class_set_devdata() to get and
247  * set this pointer.
248  * @parent: pointer to a struct class_device that is the parent of this struct
249  * class_device.  If NULL, this class_device will show up at the root of the
250  * struct class in sysfs (which is probably what you want to have happen.)
251  * @release: pointer to a release function for this struct class_device.  If
252  * set, this will be called instead of the class specific release function.
253  * Only use this if you want to override the default release function, like
254  * when you are nesting class_device structures.
255  * @uevent: pointer to a uevent function for this struct class_device.  If
256  * set, this will be called instead of the class specific uevent function.
257  * Only use this if you want to override the default uevent function, like
258  * when you are nesting class_device structures.
259  */
260 struct class_device {
261 	struct list_head	node;
262 
263 	struct kobject		kobj;
264 	struct class		* class;	/* required */
265 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
266 	struct class_device_attribute *devt_attr;
267 	struct class_device_attribute uevent_attr;
268 	struct device		* dev;		/* not necessary, but nice to have */
269 	void			* class_data;	/* class-specific data */
270 	struct class_device	*parent;	/* parent of this child device, if there is one */
271 	struct attribute_group  ** groups;	/* optional groups */
272 
273 	void	(*release)(struct class_device *dev);
274 	int	(*uevent)(struct class_device *dev, char **envp,
275 			   int num_envp, char *buffer, int buffer_size);
276 	char	class_id[BUS_ID_SIZE];	/* unique to this class */
277 };
278 
279 static inline void *
280 class_get_devdata (struct class_device *dev)
281 {
282 	return dev->class_data;
283 }
284 
285 static inline void
286 class_set_devdata (struct class_device *dev, void *data)
287 {
288 	dev->class_data = data;
289 }
290 
291 
292 extern int __must_check class_device_register(struct class_device *);
293 extern void class_device_unregister(struct class_device *);
294 extern void class_device_initialize(struct class_device *);
295 extern int __must_check class_device_add(struct class_device *);
296 extern void class_device_del(struct class_device *);
297 
298 extern struct class_device * class_device_get(struct class_device *);
299 extern void class_device_put(struct class_device *);
300 
301 extern void class_device_remove_file(struct class_device *,
302 				     const struct class_device_attribute *);
303 extern int __must_check class_device_create_bin_file(struct class_device *,
304 					struct bin_attribute *);
305 extern void class_device_remove_bin_file(struct class_device *,
306 					 struct bin_attribute *);
307 
308 struct class_interface {
309 	struct list_head	node;
310 	struct class		*class;
311 
312 	int (*add)	(struct class_device *, struct class_interface *);
313 	void (*remove)	(struct class_device *, struct class_interface *);
314 	int (*add_dev)		(struct device *, struct class_interface *);
315 	void (*remove_dev)	(struct device *, struct class_interface *);
316 };
317 
318 extern int __must_check class_interface_register(struct class_interface *);
319 extern void class_interface_unregister(struct class_interface *);
320 
321 extern struct class *class_create(struct module *owner, const char *name);
322 extern void class_destroy(struct class *cls);
323 extern struct class_device *class_device_create(struct class *cls,
324 						struct class_device *parent,
325 						dev_t devt,
326 						struct device *device,
327 						const char *fmt, ...)
328 					__attribute__((format(printf,5,6)));
329 extern void class_device_destroy(struct class *cls, dev_t devt);
330 
331 struct device_type {
332 	struct device_attribute *attrs;
333 	int (*uevent)(struct device *dev, char **envp, int num_envp,
334 		      char *buffer, int buffer_size);
335 	void (*release)(struct device *dev);
336 };
337 
338 /* interface for exporting device attributes */
339 struct device_attribute {
340 	struct attribute	attr;
341 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
342 			char *buf);
343 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
344 			 const char *buf, size_t count);
345 };
346 
347 #define DEVICE_ATTR(_name,_mode,_show,_store) \
348 struct device_attribute dev_attr_##_name = __ATTR(_name,_mode,_show,_store)
349 
350 extern int __must_check device_create_file(struct device *device,
351 					struct device_attribute * entry);
352 extern void device_remove_file(struct device * dev, struct device_attribute * attr);
353 extern int __must_check device_create_bin_file(struct device *dev,
354 					       struct bin_attribute *attr);
355 extern void device_remove_bin_file(struct device *dev,
356 				   struct bin_attribute *attr);
357 extern int device_schedule_callback(struct device *dev,
358 		void (*func)(struct device *));
359 
360 /* device resource management */
361 typedef void (*dr_release_t)(struct device *dev, void *res);
362 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
363 
364 #ifdef CONFIG_DEBUG_DEVRES
365 extern void * __devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
366 			     const char *name);
367 #define devres_alloc(release, size, gfp) \
368 	__devres_alloc(release, size, gfp, #release)
369 #else
370 extern void * devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
371 #endif
372 extern void devres_free(void *res);
373 extern void devres_add(struct device *dev, void *res);
374 extern void * devres_find(struct device *dev, dr_release_t release,
375 			  dr_match_t match, void *match_data);
376 extern void * devres_get(struct device *dev, void *new_res,
377 			 dr_match_t match, void *match_data);
378 extern void * devres_remove(struct device *dev, dr_release_t release,
379 			    dr_match_t match, void *match_data);
380 extern int devres_destroy(struct device *dev, dr_release_t release,
381 			  dr_match_t match, void *match_data);
382 
383 /* devres group */
384 extern void * __must_check devres_open_group(struct device *dev, void *id,
385 					     gfp_t gfp);
386 extern void devres_close_group(struct device *dev, void *id);
387 extern void devres_remove_group(struct device *dev, void *id);
388 extern int devres_release_group(struct device *dev, void *id);
389 
390 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
391 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
392 extern void devm_kfree(struct device *dev, void *p);
393 
394 struct device {
395 	struct klist		klist_children;
396 	struct klist_node	knode_parent;		/* node in sibling list */
397 	struct klist_node	knode_driver;
398 	struct klist_node	knode_bus;
399 	struct device 	* parent;
400 
401 	struct kobject kobj;
402 	char	bus_id[BUS_ID_SIZE];	/* position on parent bus */
403 	struct device_type	*type;
404 	unsigned		is_registered:1;
405 	struct device_attribute uevent_attr;
406 	struct device_attribute *devt_attr;
407 
408 	struct semaphore	sem;	/* semaphore to synchronize calls to
409 					 * its driver.
410 					 */
411 
412 	struct bus_type	* bus;		/* type of bus device is on */
413 	struct device_driver *driver;	/* which driver has allocated this
414 					   device */
415 	void		*driver_data;	/* data private to the driver */
416 	void		*platform_data;	/* Platform specific data, device
417 					   core doesn't touch it */
418 	struct dev_pm_info	power;
419 
420 #ifdef CONFIG_NUMA
421 	int		numa_node;	/* NUMA node this device is close to */
422 #endif
423 	u64		*dma_mask;	/* dma mask (if dma'able device) */
424 	u64		coherent_dma_mask;/* Like dma_mask, but for
425 					     alloc_coherent mappings as
426 					     not all hardware supports
427 					     64 bit addresses for consistent
428 					     allocations such descriptors. */
429 
430 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
431 
432 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
433 					     override */
434 	/* arch specific additions */
435 	struct dev_archdata	archdata;
436 
437 	spinlock_t		devres_lock;
438 	struct list_head	devres_head;
439 
440 	/* class_device migration path */
441 	struct list_head	node;
442 	struct class		*class;
443 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
444 	struct attribute_group	**groups;	/* optional groups */
445 	int			uevent_suppress;
446 
447 	void	(*release)(struct device * dev);
448 };
449 
450 #ifdef CONFIG_NUMA
451 static inline int dev_to_node(struct device *dev)
452 {
453 	return dev->numa_node;
454 }
455 static inline void set_dev_node(struct device *dev, int node)
456 {
457 	dev->numa_node = node;
458 }
459 #else
460 static inline int dev_to_node(struct device *dev)
461 {
462 	return -1;
463 }
464 static inline void set_dev_node(struct device *dev, int node)
465 {
466 }
467 #endif
468 
469 static inline void *
470 dev_get_drvdata (struct device *dev)
471 {
472 	return dev->driver_data;
473 }
474 
475 static inline void
476 dev_set_drvdata (struct device *dev, void *data)
477 {
478 	dev->driver_data = data;
479 }
480 
481 static inline int device_is_registered(struct device *dev)
482 {
483 	return dev->is_registered;
484 }
485 
486 void driver_init(void);
487 
488 /*
489  * High level routines for use by the bus drivers
490  */
491 extern int __must_check device_register(struct device * dev);
492 extern void device_unregister(struct device * dev);
493 extern void device_initialize(struct device * dev);
494 extern int __must_check device_add(struct device * dev);
495 extern void device_del(struct device * dev);
496 extern int device_for_each_child(struct device *, void *,
497 		     int (*fn)(struct device *, void *));
498 extern struct device *device_find_child(struct device *, void *data,
499 					int (*match)(struct device *, void *));
500 extern int device_rename(struct device *dev, char *new_name);
501 extern int device_move(struct device *dev, struct device *new_parent);
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(struct class *cls, struct device *parent,
517 				    dev_t devt, const char *fmt, ...)
518 				    __attribute__((format(printf,4,5)));
519 extern void device_destroy(struct class *cls, dev_t devt);
520 
521 /*
522  * Platform "fixup" functions - allow the platform to have their say
523  * about devices and actions that the general device layer doesn't
524  * know about.
525  */
526 /* Notify platform of device discovery */
527 extern int (*platform_notify)(struct device * dev);
528 
529 extern int (*platform_notify_remove)(struct device * dev);
530 
531 
532 /**
533  * get_device - atomically increment the reference count for the device.
534  *
535  */
536 extern struct device * get_device(struct device * dev);
537 extern void put_device(struct device * dev);
538 
539 
540 /* drivers/base/power/shutdown.c */
541 extern void device_shutdown(void);
542 
543 
544 /* drivers/base/firmware.c */
545 extern int __must_check firmware_register(struct subsystem *);
546 extern void firmware_unregister(struct subsystem *);
547 
548 /* debugging and troubleshooting/diagnostic helpers. */
549 extern const char *dev_driver_string(struct device *dev);
550 #define dev_printk(level, dev, format, arg...)	\
551 	printk(level "%s %s: " format , dev_driver_string(dev) , (dev)->bus_id , ## arg)
552 
553 #ifdef DEBUG
554 #define dev_dbg(dev, format, arg...)		\
555 	dev_printk(KERN_DEBUG , dev , format , ## arg)
556 #else
557 #define dev_dbg(dev, format, arg...) do { (void)(dev); } while (0)
558 #endif
559 
560 #define dev_err(dev, format, arg...)		\
561 	dev_printk(KERN_ERR , dev , format , ## arg)
562 #define dev_info(dev, format, arg...)		\
563 	dev_printk(KERN_INFO , dev , format , ## arg)
564 #define dev_warn(dev, format, arg...)		\
565 	dev_printk(KERN_WARNING , dev , format , ## arg)
566 #define dev_notice(dev, format, arg...)		\
567 	dev_printk(KERN_NOTICE , dev , format , ## arg)
568 
569 /* Create alias, so I can be autoloaded. */
570 #define MODULE_ALIAS_CHARDEV(major,minor) \
571 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
572 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
573 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
574 #endif /* _DEVICE_H_ */
575