xref: /linux-6.15/include/linux/device.h (revision 757dea93)
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 	struct bus_attribute drivers_autoprobe_attr;
68 	struct bus_attribute drivers_probe_attr;
69 
70 	int		(*match)(struct device * dev, struct device_driver * drv);
71 	int		(*uevent)(struct device *dev, char **envp,
72 				  int num_envp, char *buffer, int buffer_size);
73 	int		(*probe)(struct device * dev);
74 	int		(*remove)(struct device * dev);
75 	void		(*shutdown)(struct device * dev);
76 
77 	int (*suspend)(struct device * dev, pm_message_t state);
78 	int (*suspend_late)(struct device * dev, pm_message_t state);
79 	int (*resume_early)(struct device * dev);
80 	int (*resume)(struct device * dev);
81 
82 	unsigned int drivers_autoprobe:1;
83 };
84 
85 extern int __must_check bus_register(struct bus_type * bus);
86 extern void bus_unregister(struct bus_type * bus);
87 
88 extern int __must_check bus_rescan_devices(struct bus_type * bus);
89 
90 /* iterator helpers for buses */
91 
92 int bus_for_each_dev(struct bus_type * bus, struct device * start, void * data,
93 		     int (*fn)(struct device *, void *));
94 struct device * bus_find_device(struct bus_type *bus, struct device *start,
95 				void *data, int (*match)(struct device *, void *));
96 
97 int __must_check bus_for_each_drv(struct bus_type *bus,
98 		struct device_driver *start, void *data,
99 		int (*fn)(struct device_driver *, void *));
100 
101 /*
102  * Bus notifiers: Get notified of addition/removal of devices
103  * and binding/unbinding of drivers to devices.
104  * In the long run, it should be a replacement for the platform
105  * notify hooks.
106  */
107 struct notifier_block;
108 
109 extern int bus_register_notifier(struct bus_type *bus,
110 				 struct notifier_block *nb);
111 extern int bus_unregister_notifier(struct bus_type *bus,
112 				   struct notifier_block *nb);
113 
114 /* All 4 notifers below get called with the target struct device *
115  * as an argument. Note that those functions are likely to be called
116  * with the device semaphore held in the core, so be careful.
117  */
118 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
119 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device removed */
120 #define BUS_NOTIFY_BOUND_DRIVER		0x00000003 /* driver bound to device */
121 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000004 /* driver about to be
122 						      unbound */
123 
124 struct device_driver {
125 	const char		* name;
126 	struct bus_type		* bus;
127 
128 	struct kobject		kobj;
129 	struct klist		klist_devices;
130 	struct klist_node	knode_bus;
131 
132 	struct module		* owner;
133 	const char 		* mod_name;	/* used for built-in modules */
134 	struct module_kobject	* mkobj;
135 
136 	int	(*probe)	(struct device * dev);
137 	int	(*remove)	(struct device * dev);
138 	void	(*shutdown)	(struct device * dev);
139 	int	(*suspend)	(struct device * dev, pm_message_t state);
140 	int	(*resume)	(struct device * dev);
141 };
142 
143 
144 extern int __must_check driver_register(struct device_driver * drv);
145 extern void driver_unregister(struct device_driver * drv);
146 
147 extern struct device_driver * get_driver(struct device_driver * drv);
148 extern void put_driver(struct device_driver * drv);
149 extern struct device_driver *driver_find(const char *name, struct bus_type *bus);
150 extern int driver_probe_done(void);
151 
152 /* sysfs interface for exporting driver attributes */
153 
154 struct driver_attribute {
155 	struct attribute	attr;
156 	ssize_t (*show)(struct device_driver *, char * buf);
157 	ssize_t (*store)(struct device_driver *, const char * buf, size_t count);
158 };
159 
160 #define DRIVER_ATTR(_name,_mode,_show,_store)	\
161 struct driver_attribute driver_attr_##_name = __ATTR(_name,_mode,_show,_store)
162 
163 extern int __must_check driver_create_file(struct device_driver *,
164 					struct driver_attribute *);
165 extern void driver_remove_file(struct device_driver *, struct driver_attribute *);
166 
167 extern int __must_check driver_for_each_device(struct device_driver * drv,
168 		struct device *start, void *data,
169 		int (*fn)(struct device *, void *));
170 struct device * driver_find_device(struct device_driver *drv,
171 				   struct device *start, void *data,
172 				   int (*match)(struct device *, void *));
173 
174 /*
175  * device classes
176  */
177 struct class {
178 	const char		* name;
179 	struct module		* owner;
180 
181 	struct kset		subsys;
182 	struct list_head	children;
183 	struct list_head	devices;
184 	struct list_head	interfaces;
185 	struct kset		class_dirs;
186 	struct semaphore	sem;	/* locks both the children and interfaces lists */
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 /*
332  * The type of device, "struct device" is embedded in. A class
333  * or bus can contain devices of different types
334  * like "partitions" and "disks", "mouse" and "event".
335  * This identifies the device type and carries type-specific
336  * information, equivalent to the kobj_type of a kobject.
337  * If "name" is specified, the uevent will contain it in
338  * the DEVTYPE variable.
339  */
340 struct device_type {
341 	const char *name;
342 	struct attribute_group **groups;
343 	int (*uevent)(struct device *dev, char **envp, int num_envp,
344 		      char *buffer, int buffer_size);
345 	void (*release)(struct device *dev);
346 	int (*suspend)(struct device * dev, pm_message_t state);
347 	int (*resume)(struct device * dev);
348 };
349 
350 /* interface for exporting device attributes */
351 struct device_attribute {
352 	struct attribute	attr;
353 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
354 			char *buf);
355 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
356 			 const char *buf, size_t count);
357 };
358 
359 #define DEVICE_ATTR(_name,_mode,_show,_store) \
360 struct device_attribute dev_attr_##_name = __ATTR(_name,_mode,_show,_store)
361 
362 extern int __must_check device_create_file(struct device *device,
363 					struct device_attribute * entry);
364 extern void device_remove_file(struct device * dev, struct device_attribute * attr);
365 extern int __must_check device_create_bin_file(struct device *dev,
366 					       struct bin_attribute *attr);
367 extern void device_remove_bin_file(struct device *dev,
368 				   struct bin_attribute *attr);
369 extern int device_schedule_callback_owner(struct device *dev,
370 		void (*func)(struct device *), struct module *owner);
371 
372 /* This is a macro to avoid include problems with THIS_MODULE */
373 #define device_schedule_callback(dev, func)			\
374 	device_schedule_callback_owner(dev, func, THIS_MODULE)
375 
376 /* device resource management */
377 typedef void (*dr_release_t)(struct device *dev, void *res);
378 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
379 
380 #ifdef CONFIG_DEBUG_DEVRES
381 extern void * __devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
382 			     const char *name);
383 #define devres_alloc(release, size, gfp) \
384 	__devres_alloc(release, size, gfp, #release)
385 #else
386 extern void * devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
387 #endif
388 extern void devres_free(void *res);
389 extern void devres_add(struct device *dev, void *res);
390 extern void * devres_find(struct device *dev, dr_release_t release,
391 			  dr_match_t match, void *match_data);
392 extern void * devres_get(struct device *dev, void *new_res,
393 			 dr_match_t match, void *match_data);
394 extern void * devres_remove(struct device *dev, dr_release_t release,
395 			    dr_match_t match, void *match_data);
396 extern int devres_destroy(struct device *dev, dr_release_t release,
397 			  dr_match_t match, void *match_data);
398 
399 /* devres group */
400 extern void * __must_check devres_open_group(struct device *dev, void *id,
401 					     gfp_t gfp);
402 extern void devres_close_group(struct device *dev, void *id);
403 extern void devres_remove_group(struct device *dev, void *id);
404 extern int devres_release_group(struct device *dev, void *id);
405 
406 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
407 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
408 extern void devm_kfree(struct device *dev, void *p);
409 
410 struct device {
411 	struct klist		klist_children;
412 	struct klist_node	knode_parent;		/* node in sibling list */
413 	struct klist_node	knode_driver;
414 	struct klist_node	knode_bus;
415 	struct device 	* parent;
416 
417 	struct kobject kobj;
418 	char	bus_id[BUS_ID_SIZE];	/* position on parent bus */
419 	struct device_type	*type;
420 	unsigned		is_registered:1;
421 	struct device_attribute uevent_attr;
422 	struct device_attribute *devt_attr;
423 
424 	struct semaphore	sem;	/* semaphore to synchronize calls to
425 					 * its driver.
426 					 */
427 
428 	struct bus_type	* bus;		/* type of bus device is on */
429 	struct device_driver *driver;	/* which driver has allocated this
430 					   device */
431 	void		*driver_data;	/* data private to the driver */
432 	void		*platform_data;	/* Platform specific data, device
433 					   core doesn't touch it */
434 	struct dev_pm_info	power;
435 
436 #ifdef CONFIG_NUMA
437 	int		numa_node;	/* NUMA node this device is close to */
438 #endif
439 	u64		*dma_mask;	/* dma mask (if dma'able device) */
440 	u64		coherent_dma_mask;/* Like dma_mask, but for
441 					     alloc_coherent mappings as
442 					     not all hardware supports
443 					     64 bit addresses for consistent
444 					     allocations such descriptors. */
445 
446 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
447 
448 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
449 					     override */
450 	/* arch specific additions */
451 	struct dev_archdata	archdata;
452 
453 	spinlock_t		devres_lock;
454 	struct list_head	devres_head;
455 
456 	/* class_device migration path */
457 	struct list_head	node;
458 	struct class		*class;
459 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
460 	struct attribute_group	**groups;	/* optional groups */
461 	int			uevent_suppress;
462 
463 	void	(*release)(struct device * dev);
464 };
465 
466 #ifdef CONFIG_NUMA
467 static inline int dev_to_node(struct device *dev)
468 {
469 	return dev->numa_node;
470 }
471 static inline void set_dev_node(struct device *dev, int node)
472 {
473 	dev->numa_node = node;
474 }
475 #else
476 static inline int dev_to_node(struct device *dev)
477 {
478 	return -1;
479 }
480 static inline void set_dev_node(struct device *dev, int node)
481 {
482 }
483 #endif
484 
485 static inline void *
486 dev_get_drvdata (struct device *dev)
487 {
488 	return dev->driver_data;
489 }
490 
491 static inline void
492 dev_set_drvdata (struct device *dev, void *data)
493 {
494 	dev->driver_data = data;
495 }
496 
497 static inline int device_is_registered(struct device *dev)
498 {
499 	return dev->is_registered;
500 }
501 
502 void driver_init(void);
503 
504 /*
505  * High level routines for use by the bus drivers
506  */
507 extern int __must_check device_register(struct device * dev);
508 extern void device_unregister(struct device * dev);
509 extern void device_initialize(struct device * dev);
510 extern int __must_check device_add(struct device * dev);
511 extern void device_del(struct device * dev);
512 extern int device_for_each_child(struct device *, void *,
513 		     int (*fn)(struct device *, void *));
514 extern struct device *device_find_child(struct device *, void *data,
515 					int (*match)(struct device *, void *));
516 extern int device_rename(struct device *dev, char *new_name);
517 extern int device_move(struct device *dev, struct device *new_parent);
518 
519 /*
520  * Manual binding of a device to driver. See drivers/base/bus.c
521  * for information on use.
522  */
523 extern int __must_check device_bind_driver(struct device *dev);
524 extern void device_release_driver(struct device * dev);
525 extern int  __must_check device_attach(struct device * dev);
526 extern int __must_check driver_attach(struct device_driver *drv);
527 extern int __must_check device_reprobe(struct device *dev);
528 
529 /*
530  * Easy functions for dynamically creating devices on the fly
531  */
532 extern struct device *device_create(struct class *cls, struct device *parent,
533 				    dev_t devt, const char *fmt, ...)
534 				    __attribute__((format(printf,4,5)));
535 extern void device_destroy(struct class *cls, dev_t devt);
536 
537 /*
538  * Platform "fixup" functions - allow the platform to have their say
539  * about devices and actions that the general device layer doesn't
540  * know about.
541  */
542 /* Notify platform of device discovery */
543 extern int (*platform_notify)(struct device * dev);
544 
545 extern int (*platform_notify_remove)(struct device * dev);
546 
547 
548 /**
549  * get_device - atomically increment the reference count for the device.
550  *
551  */
552 extern struct device * get_device(struct device * dev);
553 extern void put_device(struct device * dev);
554 
555 
556 /* drivers/base/power/shutdown.c */
557 extern void device_shutdown(void);
558 
559 
560 /* drivers/base/firmware.c */
561 extern int __must_check firmware_register(struct kset *);
562 extern void firmware_unregister(struct kset *);
563 
564 /* debugging and troubleshooting/diagnostic helpers. */
565 extern const char *dev_driver_string(struct device *dev);
566 #define dev_printk(level, dev, format, arg...)	\
567 	printk(level "%s %s: " format , dev_driver_string(dev) , (dev)->bus_id , ## arg)
568 
569 #ifdef DEBUG
570 #define dev_dbg(dev, format, arg...)		\
571 	dev_printk(KERN_DEBUG , dev , format , ## arg)
572 #else
573 static inline int __attribute__ ((format (printf, 2, 3)))
574 dev_dbg(struct device * dev, const char * fmt, ...)
575 {
576 	return 0;
577 }
578 #endif
579 
580 #define dev_err(dev, format, arg...)		\
581 	dev_printk(KERN_ERR , dev , format , ## arg)
582 #define dev_info(dev, format, arg...)		\
583 	dev_printk(KERN_INFO , dev , format , ## arg)
584 #define dev_warn(dev, format, arg...)		\
585 	dev_printk(KERN_WARNING , dev , format , ## arg)
586 #define dev_notice(dev, format, arg...)		\
587 	dev_printk(KERN_NOTICE , dev , format , ## arg)
588 
589 /* Create alias, so I can be autoloaded. */
590 #define MODULE_ALIAS_CHARDEV(major,minor) \
591 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
592 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
593 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
594 #endif /* _DEVICE_H_ */
595