xref: /linux-6.15/include/linux/device.h (revision c537b994)
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 
132 	int	(*probe)	(struct device * dev);
133 	int	(*remove)	(struct device * dev);
134 	void	(*shutdown)	(struct device * dev);
135 	int	(*suspend)	(struct device * dev, pm_message_t state);
136 	int	(*resume)	(struct device * dev);
137 
138 	unsigned int multithread_probe:1;
139 };
140 
141 
142 extern int __must_check driver_register(struct device_driver * drv);
143 extern void driver_unregister(struct device_driver * drv);
144 
145 extern struct device_driver * get_driver(struct device_driver * drv);
146 extern void put_driver(struct device_driver * drv);
147 extern struct device_driver *driver_find(const char *name, struct bus_type *bus);
148 extern int driver_probe_done(void);
149 
150 /* sysfs interface for exporting driver attributes */
151 
152 struct driver_attribute {
153 	struct attribute	attr;
154 	ssize_t (*show)(struct device_driver *, char * buf);
155 	ssize_t (*store)(struct device_driver *, const char * buf, size_t count);
156 };
157 
158 #define DRIVER_ATTR(_name,_mode,_show,_store)	\
159 struct driver_attribute driver_attr_##_name = __ATTR(_name,_mode,_show,_store)
160 
161 extern int __must_check driver_create_file(struct device_driver *,
162 					struct driver_attribute *);
163 extern void driver_remove_file(struct device_driver *, struct driver_attribute *);
164 
165 extern int __must_check driver_for_each_device(struct device_driver * drv,
166 		struct device *start, void *data,
167 		int (*fn)(struct device *, void *));
168 struct device * driver_find_device(struct device_driver *drv,
169 				   struct device *start, void *data,
170 				   int (*match)(struct device *, void *));
171 
172 /*
173  * device classes
174  */
175 struct class {
176 	const char		* name;
177 	struct module		* owner;
178 
179 	struct subsystem	subsys;
180 	struct list_head	children;
181 	struct list_head	devices;
182 	struct list_head	interfaces;
183 	struct semaphore	sem;	/* locks both the children and interfaces lists */
184 
185 	struct kobject		*virtual_dir;
186 
187 	struct class_attribute		* class_attrs;
188 	struct class_device_attribute	* class_dev_attrs;
189 	struct device_attribute		* dev_attrs;
190 
191 	int	(*uevent)(struct class_device *dev, char **envp,
192 			   int num_envp, char *buffer, int buffer_size);
193 	int	(*dev_uevent)(struct device *dev, char **envp, int num_envp,
194 				char *buffer, int buffer_size);
195 
196 	void	(*release)(struct class_device *dev);
197 	void	(*class_release)(struct class *class);
198 	void	(*dev_release)(struct device *dev);
199 
200 	int	(*suspend)(struct device *, pm_message_t state);
201 	int	(*resume)(struct device *);
202 };
203 
204 extern int __must_check class_register(struct class *);
205 extern void class_unregister(struct class *);
206 
207 
208 struct class_attribute {
209 	struct attribute	attr;
210 	ssize_t (*show)(struct class *, char * buf);
211 	ssize_t (*store)(struct class *, const char * buf, size_t count);
212 };
213 
214 #define CLASS_ATTR(_name,_mode,_show,_store)			\
215 struct class_attribute class_attr_##_name = __ATTR(_name,_mode,_show,_store)
216 
217 extern int __must_check class_create_file(struct class *,
218 					const struct class_attribute *);
219 extern void class_remove_file(struct class *, const struct class_attribute *);
220 
221 struct class_device_attribute {
222 	struct attribute	attr;
223 	ssize_t (*show)(struct class_device *, char * buf);
224 	ssize_t (*store)(struct class_device *, const char * buf, size_t count);
225 };
226 
227 #define CLASS_DEVICE_ATTR(_name,_mode,_show,_store)		\
228 struct class_device_attribute class_device_attr_##_name = 	\
229 	__ATTR(_name,_mode,_show,_store)
230 
231 extern int __must_check class_device_create_file(struct class_device *,
232 				    const struct class_device_attribute *);
233 
234 /**
235  * struct class_device - class devices
236  * @class: pointer to the parent class for this class device.  This is required.
237  * @devt: for internal use by the driver core only.
238  * @node: for internal use by the driver core only.
239  * @kobj: for internal use by the driver core only.
240  * @devt_attr: for internal use by the driver core only.
241  * @groups: optional additional groups to be created
242  * @dev: if set, a symlink to the struct device is created in the sysfs
243  * directory for this struct class device.
244  * @class_data: pointer to whatever you want to store here for this struct
245  * class_device.  Use class_get_devdata() and class_set_devdata() to get and
246  * set this pointer.
247  * @parent: pointer to a struct class_device that is the parent of this struct
248  * class_device.  If NULL, this class_device will show up at the root of the
249  * struct class in sysfs (which is probably what you want to have happen.)
250  * @release: pointer to a release function for this struct class_device.  If
251  * set, this will be called instead of the class specific release function.
252  * Only use this if you want to override the default release function, like
253  * when you are nesting class_device structures.
254  * @uevent: pointer to a uevent function for this struct class_device.  If
255  * set, this will be called instead of the class specific uevent function.
256  * Only use this if you want to override the default uevent function, like
257  * when you are nesting class_device structures.
258  */
259 struct class_device {
260 	struct list_head	node;
261 
262 	struct kobject		kobj;
263 	struct class		* class;	/* required */
264 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
265 	struct class_device_attribute *devt_attr;
266 	struct class_device_attribute uevent_attr;
267 	struct device		* dev;		/* not necessary, but nice to have */
268 	void			* class_data;	/* class-specific data */
269 	struct class_device	*parent;	/* parent of this child device, if there is one */
270 	struct attribute_group  ** groups;	/* optional groups */
271 
272 	void	(*release)(struct class_device *dev);
273 	int	(*uevent)(struct class_device *dev, char **envp,
274 			   int num_envp, char *buffer, int buffer_size);
275 	char	class_id[BUS_ID_SIZE];	/* unique to this class */
276 };
277 
278 static inline void *
279 class_get_devdata (struct class_device *dev)
280 {
281 	return dev->class_data;
282 }
283 
284 static inline void
285 class_set_devdata (struct class_device *dev, void *data)
286 {
287 	dev->class_data = data;
288 }
289 
290 
291 extern int __must_check class_device_register(struct class_device *);
292 extern void class_device_unregister(struct class_device *);
293 extern void class_device_initialize(struct class_device *);
294 extern int __must_check class_device_add(struct class_device *);
295 extern void class_device_del(struct class_device *);
296 
297 extern struct class_device * class_device_get(struct class_device *);
298 extern void class_device_put(struct class_device *);
299 
300 extern void class_device_remove_file(struct class_device *,
301 				     const struct class_device_attribute *);
302 extern int __must_check class_device_create_bin_file(struct class_device *,
303 					struct bin_attribute *);
304 extern void class_device_remove_bin_file(struct class_device *,
305 					 struct bin_attribute *);
306 
307 struct class_interface {
308 	struct list_head	node;
309 	struct class		*class;
310 
311 	int (*add)	(struct class_device *, struct class_interface *);
312 	void (*remove)	(struct class_device *, struct class_interface *);
313 	int (*add_dev)		(struct device *, struct class_interface *);
314 	void (*remove_dev)	(struct device *, struct class_interface *);
315 };
316 
317 extern int __must_check class_interface_register(struct class_interface *);
318 extern void class_interface_unregister(struct class_interface *);
319 
320 extern struct class *class_create(struct module *owner, const char *name);
321 extern void class_destroy(struct class *cls);
322 extern struct class_device *class_device_create(struct class *cls,
323 						struct class_device *parent,
324 						dev_t devt,
325 						struct device *device,
326 						const char *fmt, ...)
327 					__attribute__((format(printf,5,6)));
328 extern void class_device_destroy(struct class *cls, dev_t devt);
329 
330 struct device_type {
331 	struct device_attribute *attrs;
332 	int (*uevent)(struct device *dev, char **envp, int num_envp,
333 		      char *buffer, int buffer_size);
334 	void (*release)(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 
357 /* device resource management */
358 typedef void (*dr_release_t)(struct device *dev, void *res);
359 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
360 
361 #ifdef CONFIG_DEBUG_DEVRES
362 extern void * __devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
363 			     const char *name);
364 #define devres_alloc(release, size, gfp) \
365 	__devres_alloc(release, size, gfp, #release)
366 #else
367 extern void * devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
368 #endif
369 extern void devres_free(void *res);
370 extern void devres_add(struct device *dev, void *res);
371 extern void * devres_find(struct device *dev, dr_release_t release,
372 			  dr_match_t match, void *match_data);
373 extern void * devres_get(struct device *dev, void *new_res,
374 			 dr_match_t match, void *match_data);
375 extern void * devres_remove(struct device *dev, dr_release_t release,
376 			    dr_match_t match, void *match_data);
377 extern int devres_destroy(struct device *dev, dr_release_t release,
378 			  dr_match_t match, void *match_data);
379 
380 /* devres group */
381 extern void * __must_check devres_open_group(struct device *dev, void *id,
382 					     gfp_t gfp);
383 extern void devres_close_group(struct device *dev, void *id);
384 extern void devres_remove_group(struct device *dev, void *id);
385 extern int devres_release_group(struct device *dev, void *id);
386 
387 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
388 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
389 extern void devm_kfree(struct device *dev, void *p);
390 
391 struct device {
392 	struct klist		klist_children;
393 	struct klist_node	knode_parent;		/* node in sibling list */
394 	struct klist_node	knode_driver;
395 	struct klist_node	knode_bus;
396 	struct device 	* parent;
397 
398 	struct kobject kobj;
399 	char	bus_id[BUS_ID_SIZE];	/* position on parent bus */
400 	struct device_type	*type;
401 	unsigned		is_registered:1;
402 	struct device_attribute uevent_attr;
403 	struct device_attribute *devt_attr;
404 
405 	struct semaphore	sem;	/* semaphore to synchronize calls to
406 					 * its driver.
407 					 */
408 
409 	struct bus_type	* bus;		/* type of bus device is on */
410 	struct device_driver *driver;	/* which driver has allocated this
411 					   device */
412 	void		*driver_data;	/* data private to the driver */
413 	void		*platform_data;	/* Platform specific data, device
414 					   core doesn't touch it */
415 	struct dev_pm_info	power;
416 
417 #ifdef CONFIG_NUMA
418 	int		numa_node;	/* NUMA node this device is close to */
419 #endif
420 	u64		*dma_mask;	/* dma mask (if dma'able device) */
421 	u64		coherent_dma_mask;/* Like dma_mask, but for
422 					     alloc_coherent mappings as
423 					     not all hardware supports
424 					     64 bit addresses for consistent
425 					     allocations such descriptors. */
426 
427 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
428 
429 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
430 					     override */
431 	/* arch specific additions */
432 	struct dev_archdata	archdata;
433 
434 	spinlock_t		devres_lock;
435 	struct list_head	devres_head;
436 
437 	/* class_device migration path */
438 	struct list_head	node;
439 	struct class		*class;
440 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
441 	struct attribute_group	**groups;	/* optional groups */
442 	int			uevent_suppress;
443 
444 	void	(*release)(struct device * dev);
445 };
446 
447 #ifdef CONFIG_NUMA
448 static inline int dev_to_node(struct device *dev)
449 {
450 	return dev->numa_node;
451 }
452 static inline void set_dev_node(struct device *dev, int node)
453 {
454 	dev->numa_node = node;
455 }
456 #else
457 static inline int dev_to_node(struct device *dev)
458 {
459 	return -1;
460 }
461 static inline void set_dev_node(struct device *dev, int node)
462 {
463 }
464 #endif
465 
466 static inline void *
467 dev_get_drvdata (struct device *dev)
468 {
469 	return dev->driver_data;
470 }
471 
472 static inline void
473 dev_set_drvdata (struct device *dev, void *data)
474 {
475 	dev->driver_data = data;
476 }
477 
478 static inline int device_is_registered(struct device *dev)
479 {
480 	return dev->is_registered;
481 }
482 
483 void driver_init(void);
484 
485 /*
486  * High level routines for use by the bus drivers
487  */
488 extern int __must_check device_register(struct device * dev);
489 extern void device_unregister(struct device * dev);
490 extern void device_initialize(struct device * dev);
491 extern int __must_check device_add(struct device * dev);
492 extern void device_del(struct device * dev);
493 extern int device_for_each_child(struct device *, void *,
494 		     int (*fn)(struct device *, void *));
495 extern struct device *device_find_child(struct device *, void *data,
496 					int (*match)(struct device *, void *));
497 extern int device_rename(struct device *dev, char *new_name);
498 extern int device_move(struct device *dev, struct device *new_parent);
499 
500 /*
501  * Manual binding of a device to driver. See drivers/base/bus.c
502  * for information on use.
503  */
504 extern int __must_check device_bind_driver(struct device *dev);
505 extern void device_release_driver(struct device * dev);
506 extern int  __must_check device_attach(struct device * dev);
507 extern int __must_check driver_attach(struct device_driver *drv);
508 extern int __must_check device_reprobe(struct device *dev);
509 
510 /*
511  * Easy functions for dynamically creating devices on the fly
512  */
513 extern struct device *device_create(struct class *cls, struct device *parent,
514 				    dev_t devt, const char *fmt, ...)
515 				    __attribute__((format(printf,4,5)));
516 extern void device_destroy(struct class *cls, dev_t devt);
517 
518 /*
519  * Platform "fixup" functions - allow the platform to have their say
520  * about devices and actions that the general device layer doesn't
521  * know about.
522  */
523 /* Notify platform of device discovery */
524 extern int (*platform_notify)(struct device * dev);
525 
526 extern int (*platform_notify_remove)(struct device * dev);
527 
528 
529 /**
530  * get_device - atomically increment the reference count for the device.
531  *
532  */
533 extern struct device * get_device(struct device * dev);
534 extern void put_device(struct device * dev);
535 
536 
537 /* drivers/base/power/shutdown.c */
538 extern void device_shutdown(void);
539 
540 
541 /* drivers/base/firmware.c */
542 extern int __must_check firmware_register(struct subsystem *);
543 extern void firmware_unregister(struct subsystem *);
544 
545 /* debugging and troubleshooting/diagnostic helpers. */
546 extern const char *dev_driver_string(struct device *dev);
547 #define dev_printk(level, dev, format, arg...)	\
548 	printk(level "%s %s: " format , dev_driver_string(dev) , (dev)->bus_id , ## arg)
549 
550 #ifdef DEBUG
551 #define dev_dbg(dev, format, arg...)		\
552 	dev_printk(KERN_DEBUG , dev , format , ## arg)
553 #else
554 #define dev_dbg(dev, format, arg...) do { (void)(dev); } while (0)
555 #endif
556 
557 #define dev_err(dev, format, arg...)		\
558 	dev_printk(KERN_ERR , dev , format , ## arg)
559 #define dev_info(dev, format, arg...)		\
560 	dev_printk(KERN_INFO , dev , format , ## arg)
561 #define dev_warn(dev, format, arg...)		\
562 	dev_printk(KERN_WARNING , dev , format , ## arg)
563 #define dev_notice(dev, format, arg...)		\
564 	dev_printk(KERN_NOTICE , dev , format , ## arg)
565 
566 /* Create alias, so I can be autoloaded. */
567 #define MODULE_ALIAS_CHARDEV(major,minor) \
568 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
569 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
570 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
571 #endif /* _DEVICE_H_ */
572