xref: /linux-6.15/include/linux/device.h (revision b963a844)
1 /*
2  * device.h - generic, centralized driver model
3  *
4  * Copyright (c) 2001-2003 Patrick Mochel <[email protected]>
5  *
6  * This file is released under the GPLv2
7  *
8  * See Documentation/driver-model/ for more information.
9  */
10 
11 #ifndef _DEVICE_H_
12 #define _DEVICE_H_
13 
14 #include <linux/ioport.h>
15 #include <linux/kobject.h>
16 #include <linux/klist.h>
17 #include <linux/list.h>
18 #include <linux/compiler.h>
19 #include <linux/types.h>
20 #include <linux/module.h>
21 #include <linux/pm.h>
22 #include <asm/semaphore.h>
23 #include <asm/atomic.h>
24 #include <asm/device.h>
25 
26 #define DEVICE_NAME_SIZE	50
27 #define DEVICE_NAME_HALF	__stringify(20)	/* Less than half to accommodate slop */
28 #define DEVICE_ID_SIZE		32
29 #define BUS_ID_SIZE		KOBJ_NAME_LEN
30 
31 
32 struct device;
33 struct device_driver;
34 struct class;
35 struct class_device;
36 
37 struct bus_type {
38 	const char		* name;
39 
40 	struct subsystem	subsys;
41 	struct kset		drivers;
42 	struct kset		devices;
43 	struct klist		klist_devices;
44 	struct klist		klist_drivers;
45 
46 	struct blocking_notifier_head bus_notifier;
47 
48 	struct bus_attribute	* bus_attrs;
49 	struct device_attribute	* dev_attrs;
50 	struct driver_attribute	* drv_attrs;
51 
52 	int		(*match)(struct device * dev, struct device_driver * drv);
53 	int		(*uevent)(struct device *dev, char **envp,
54 				  int num_envp, char *buffer, int buffer_size);
55 	int		(*probe)(struct device * dev);
56 	int		(*remove)(struct device * dev);
57 	void		(*shutdown)(struct device * dev);
58 
59 	int (*suspend)(struct device * dev, pm_message_t state);
60 	int (*suspend_late)(struct device * dev, pm_message_t state);
61 	int (*resume_early)(struct device * dev);
62 	int (*resume)(struct device * dev);
63 };
64 
65 extern int __must_check bus_register(struct bus_type * bus);
66 extern void bus_unregister(struct bus_type * bus);
67 
68 extern int __must_check bus_rescan_devices(struct bus_type * bus);
69 
70 /* iterator helpers for buses */
71 
72 int bus_for_each_dev(struct bus_type * bus, struct device * start, void * data,
73 		     int (*fn)(struct device *, void *));
74 struct device * bus_find_device(struct bus_type *bus, struct device *start,
75 				void *data, int (*match)(struct device *, void *));
76 
77 int __must_check bus_for_each_drv(struct bus_type *bus,
78 		struct device_driver *start, void *data,
79 		int (*fn)(struct device_driver *, void *));
80 
81 /*
82  * Bus notifiers: Get notified of addition/removal of devices
83  * and binding/unbinding of drivers to devices.
84  * In the long run, it should be a replacement for the platform
85  * notify hooks.
86  */
87 struct notifier_block;
88 
89 extern int bus_register_notifier(struct bus_type *bus,
90 				 struct notifier_block *nb);
91 extern int bus_unregister_notifier(struct bus_type *bus,
92 				   struct notifier_block *nb);
93 
94 /* All 4 notifers below get called with the target struct device *
95  * as an argument. Note that those functions are likely to be called
96  * with the device semaphore held in the core, so be careful.
97  */
98 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
99 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device removed */
100 #define BUS_NOTIFY_BOUND_DRIVER		0x00000003 /* driver bound to device */
101 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000004 /* driver about to be
102 						      unbound */
103 
104 /* driverfs interface for exporting bus attributes */
105 
106 struct bus_attribute {
107 	struct attribute	attr;
108 	ssize_t (*show)(struct bus_type *, char * buf);
109 	ssize_t (*store)(struct bus_type *, const char * buf, size_t count);
110 };
111 
112 #define BUS_ATTR(_name,_mode,_show,_store)	\
113 struct bus_attribute bus_attr_##_name = __ATTR(_name,_mode,_show,_store)
114 
115 extern int __must_check bus_create_file(struct bus_type *,
116 					struct bus_attribute *);
117 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
118 
119 struct device_driver {
120 	const char		* name;
121 	struct bus_type		* bus;
122 
123 	struct completion	unloaded;
124 	struct kobject		kobj;
125 	struct klist		klist_devices;
126 	struct klist_node	knode_bus;
127 
128 	struct module		* owner;
129 	const char 		* mod_name;	/* used for built-in modules */
130 
131 	int	(*probe)	(struct device * dev);
132 	int	(*remove)	(struct device * dev);
133 	void	(*shutdown)	(struct device * dev);
134 	int	(*suspend)	(struct device * dev, pm_message_t state);
135 	int	(*resume)	(struct device * dev);
136 
137 	unsigned int multithread_probe:1;
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 /* driverfs 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 subsystem	subsys;
179 	struct list_head	children;
180 	struct list_head	devices;
181 	struct list_head	interfaces;
182 	struct semaphore	sem;	/* locks both the children and interfaces lists */
183 
184 	struct kobject		*virtual_dir;
185 
186 	struct class_attribute		* class_attrs;
187 	struct class_device_attribute	* class_dev_attrs;
188 	struct device_attribute		* dev_attrs;
189 
190 	int	(*uevent)(struct class_device *dev, char **envp,
191 			   int num_envp, char *buffer, int buffer_size);
192 	int	(*dev_uevent)(struct device *dev, char **envp, int num_envp,
193 				char *buffer, int buffer_size);
194 
195 	void	(*release)(struct class_device *dev);
196 	void	(*class_release)(struct class *class);
197 	void	(*dev_release)(struct device *dev);
198 
199 	int	(*suspend)(struct device *, pm_message_t state);
200 	int	(*resume)(struct device *);
201 };
202 
203 extern int __must_check class_register(struct class *);
204 extern void class_unregister(struct class *);
205 
206 
207 struct class_attribute {
208 	struct attribute	attr;
209 	ssize_t (*show)(struct class *, char * buf);
210 	ssize_t (*store)(struct class *, const char * buf, size_t count);
211 };
212 
213 #define CLASS_ATTR(_name,_mode,_show,_store)			\
214 struct class_attribute class_attr_##_name = __ATTR(_name,_mode,_show,_store)
215 
216 extern int __must_check class_create_file(struct class *,
217 					const struct class_attribute *);
218 extern void class_remove_file(struct class *, const struct class_attribute *);
219 
220 struct class_device_attribute {
221 	struct attribute	attr;
222 	ssize_t (*show)(struct class_device *, char * buf);
223 	ssize_t (*store)(struct class_device *, const char * buf, size_t count);
224 };
225 
226 #define CLASS_DEVICE_ATTR(_name,_mode,_show,_store)		\
227 struct class_device_attribute class_device_attr_##_name = 	\
228 	__ATTR(_name,_mode,_show,_store)
229 
230 extern int __must_check class_device_create_file(struct class_device *,
231 				    const struct class_device_attribute *);
232 
233 /**
234  * struct class_device - class devices
235  * @class: pointer to the parent class for this class device.  This is required.
236  * @devt: for internal use by the driver core only.
237  * @node: for internal use by the driver core only.
238  * @kobj: for internal use by the driver core only.
239  * @devt_attr: for internal use by the driver core only.
240  * @groups: optional additional groups to be created
241  * @dev: if set, a symlink to the struct device is created in the sysfs
242  * directory for this struct class device.
243  * @class_data: pointer to whatever you want to store here for this struct
244  * class_device.  Use class_get_devdata() and class_set_devdata() to get and
245  * set this pointer.
246  * @parent: pointer to a struct class_device that is the parent of this struct
247  * class_device.  If NULL, this class_device will show up at the root of the
248  * struct class in sysfs (which is probably what you want to have happen.)
249  * @release: pointer to a release function for this struct class_device.  If
250  * set, this will be called instead of the class specific release function.
251  * Only use this if you want to override the default release function, like
252  * when you are nesting class_device structures.
253  * @uevent: pointer to a uevent function for this struct class_device.  If
254  * set, this will be called instead of the class specific uevent function.
255  * Only use this if you want to override the default uevent function, like
256  * when you are nesting class_device structures.
257  */
258 struct class_device {
259 	struct list_head	node;
260 
261 	struct kobject		kobj;
262 	struct class		* class;	/* required */
263 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
264 	struct class_device_attribute *devt_attr;
265 	struct class_device_attribute uevent_attr;
266 	struct device		* dev;		/* not necessary, but nice to have */
267 	void			* class_data;	/* class-specific data */
268 	struct class_device	*parent;	/* parent of this child device, if there is one */
269 	struct attribute_group  ** groups;	/* optional groups */
270 
271 	void	(*release)(struct class_device *dev);
272 	int	(*uevent)(struct class_device *dev, char **envp,
273 			   int num_envp, char *buffer, int buffer_size);
274 	char	class_id[BUS_ID_SIZE];	/* unique to this class */
275 };
276 
277 static inline void *
278 class_get_devdata (struct class_device *dev)
279 {
280 	return dev->class_data;
281 }
282 
283 static inline void
284 class_set_devdata (struct class_device *dev, void *data)
285 {
286 	dev->class_data = data;
287 }
288 
289 
290 extern int __must_check class_device_register(struct class_device *);
291 extern void class_device_unregister(struct class_device *);
292 extern void class_device_initialize(struct class_device *);
293 extern int __must_check class_device_add(struct class_device *);
294 extern void class_device_del(struct class_device *);
295 
296 extern int class_device_rename(struct class_device *, char *);
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 
358 /* device resource management */
359 typedef void (*dr_release_t)(struct device *dev, void *res);
360 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
361 
362 #ifdef CONFIG_DEBUG_DEVRES
363 extern void * __devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
364 			     const char *name);
365 #define devres_alloc(release, size, gfp) \
366 	__devres_alloc(release, size, gfp, #release)
367 #else
368 extern void * devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
369 #endif
370 extern void devres_free(void *res);
371 extern void devres_add(struct device *dev, void *res);
372 extern void * devres_find(struct device *dev, dr_release_t release,
373 			  dr_match_t match, void *match_data);
374 extern void * devres_get(struct device *dev, void *new_res,
375 			 dr_match_t match, void *match_data);
376 extern void * devres_remove(struct device *dev, dr_release_t release,
377 			    dr_match_t match, void *match_data);
378 extern int devres_destroy(struct device *dev, dr_release_t release,
379 			  dr_match_t match, void *match_data);
380 
381 /* devres group */
382 extern void * __must_check devres_open_group(struct device *dev, void *id,
383 					     gfp_t gfp);
384 extern void devres_close_group(struct device *dev, void *id);
385 extern void devres_remove_group(struct device *dev, void *id);
386 extern int devres_release_group(struct device *dev, void *id);
387 
388 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
389 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
390 extern void devm_kfree(struct device *dev, void *p);
391 
392 struct device {
393 	struct klist		klist_children;
394 	struct klist_node	knode_parent;		/* node in sibling list */
395 	struct klist_node	knode_driver;
396 	struct klist_node	knode_bus;
397 	struct device 	* parent;
398 
399 	struct kobject kobj;
400 	char	bus_id[BUS_ID_SIZE];	/* position on parent bus */
401 	struct device_type	*type;
402 	unsigned		is_registered:1;
403 	struct device_attribute uevent_attr;
404 	struct device_attribute *devt_attr;
405 
406 	struct semaphore	sem;	/* semaphore to synchronize calls to
407 					 * its driver.
408 					 */
409 
410 	struct bus_type	* bus;		/* type of bus device is on */
411 	struct device_driver *driver;	/* which driver has allocated this
412 					   device */
413 	void		*driver_data;	/* data private to the driver */
414 	void		*platform_data;	/* Platform specific data, device
415 					   core doesn't touch it */
416 	struct dev_pm_info	power;
417 
418 #ifdef CONFIG_NUMA
419 	int		numa_node;	/* NUMA node this device is close to */
420 #endif
421 	u64		*dma_mask;	/* dma mask (if dma'able device) */
422 	u64		coherent_dma_mask;/* Like dma_mask, but for
423 					     alloc_coherent mappings as
424 					     not all hardware supports
425 					     64 bit addresses for consistent
426 					     allocations such descriptors. */
427 
428 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
429 
430 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
431 					     override */
432 	/* arch specific additions */
433 	struct dev_archdata	archdata;
434 
435 	spinlock_t		devres_lock;
436 	struct list_head	devres_head;
437 
438 	/* class_device migration path */
439 	struct list_head	node;
440 	struct class		*class;
441 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
442 	struct attribute_group	**groups;	/* optional groups */
443 	int			uevent_suppress;
444 
445 	void	(*release)(struct device * dev);
446 };
447 
448 #ifdef CONFIG_NUMA
449 static inline int dev_to_node(struct device *dev)
450 {
451 	return dev->numa_node;
452 }
453 static inline void set_dev_node(struct device *dev, int node)
454 {
455 	dev->numa_node = node;
456 }
457 #else
458 static inline int dev_to_node(struct device *dev)
459 {
460 	return -1;
461 }
462 static inline void set_dev_node(struct device *dev, int node)
463 {
464 }
465 #endif
466 
467 static inline void *
468 dev_get_drvdata (struct device *dev)
469 {
470 	return dev->driver_data;
471 }
472 
473 static inline void
474 dev_set_drvdata (struct device *dev, void *data)
475 {
476 	dev->driver_data = data;
477 }
478 
479 static inline int device_is_registered(struct device *dev)
480 {
481 	return dev->is_registered;
482 }
483 
484 void driver_init(void);
485 
486 /*
487  * High level routines for use by the bus drivers
488  */
489 extern int __must_check device_register(struct device * dev);
490 extern void device_unregister(struct device * dev);
491 extern void device_initialize(struct device * dev);
492 extern int __must_check device_add(struct device * dev);
493 extern void device_del(struct device * dev);
494 extern int device_for_each_child(struct device *, void *,
495 		     int (*fn)(struct device *, void *));
496 extern struct device *device_find_child(struct device *, void *data,
497 					int (*match)(struct device *, void *));
498 extern int device_rename(struct device *dev, char *new_name);
499 extern int device_move(struct device *dev, struct device *new_parent);
500 
501 /*
502  * Manual binding of a device to driver. See drivers/base/bus.c
503  * for information on use.
504  */
505 extern int __must_check device_bind_driver(struct device *dev);
506 extern void device_release_driver(struct device * dev);
507 extern int  __must_check device_attach(struct device * dev);
508 extern int __must_check driver_attach(struct device_driver *drv);
509 extern int __must_check device_reprobe(struct device *dev);
510 
511 /*
512  * Easy functions for dynamically creating devices on the fly
513  */
514 extern struct device *device_create(struct class *cls, struct device *parent,
515 				    dev_t devt, const char *fmt, ...)
516 				    __attribute__((format(printf,4,5)));
517 extern void device_destroy(struct class *cls, dev_t devt);
518 
519 /*
520  * Platform "fixup" functions - allow the platform to have their say
521  * about devices and actions that the general device layer doesn't
522  * know about.
523  */
524 /* Notify platform of device discovery */
525 extern int (*platform_notify)(struct device * dev);
526 
527 extern int (*platform_notify_remove)(struct device * dev);
528 
529 
530 /**
531  * get_device - atomically increment the reference count for the device.
532  *
533  */
534 extern struct device * get_device(struct device * dev);
535 extern void put_device(struct device * dev);
536 
537 
538 /* drivers/base/power/shutdown.c */
539 extern void device_shutdown(void);
540 
541 
542 /* drivers/base/firmware.c */
543 extern int __must_check firmware_register(struct subsystem *);
544 extern void firmware_unregister(struct subsystem *);
545 
546 /* debugging and troubleshooting/diagnostic helpers. */
547 extern const char *dev_driver_string(struct device *dev);
548 #define dev_printk(level, dev, format, arg...)	\
549 	printk(level "%s %s: " format , dev_driver_string(dev) , (dev)->bus_id , ## arg)
550 
551 #ifdef DEBUG
552 #define dev_dbg(dev, format, arg...)		\
553 	dev_printk(KERN_DEBUG , dev , format , ## arg)
554 #else
555 #define dev_dbg(dev, format, arg...) do { (void)(dev); } while (0)
556 #endif
557 
558 #define dev_err(dev, format, arg...)		\
559 	dev_printk(KERN_ERR , dev , format , ## arg)
560 #define dev_info(dev, format, arg...)		\
561 	dev_printk(KERN_INFO , dev , format , ## arg)
562 #define dev_warn(dev, format, arg...)		\
563 	dev_printk(KERN_WARNING , dev , format , ## arg)
564 #define dev_notice(dev, format, arg...)		\
565 	dev_printk(KERN_NOTICE , dev , format , ## arg)
566 
567 /* Create alias, so I can be autoloaded. */
568 #define MODULE_ALIAS_CHARDEV(major,minor) \
569 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
570 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
571 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
572 #endif /* _DEVICE_H_ */
573