xref: /linux-6.15/include/linux/device.h (revision b454cc66)
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 struct device {
358 	struct klist		klist_children;
359 	struct klist_node	knode_parent;		/* node in sibling list */
360 	struct klist_node	knode_driver;
361 	struct klist_node	knode_bus;
362 	struct device 	* parent;
363 
364 	struct kobject kobj;
365 	char	bus_id[BUS_ID_SIZE];	/* position on parent bus */
366 	struct device_type	*type;
367 	unsigned		is_registered:1;
368 	struct device_attribute uevent_attr;
369 	struct device_attribute *devt_attr;
370 
371 	struct semaphore	sem;	/* semaphore to synchronize calls to
372 					 * its driver.
373 					 */
374 
375 	struct bus_type	* bus;		/* type of bus device is on */
376 	struct device_driver *driver;	/* which driver has allocated this
377 					   device */
378 	void		*driver_data;	/* data private to the driver */
379 	void		*platform_data;	/* Platform specific data, device
380 					   core doesn't touch it */
381 	struct dev_pm_info	power;
382 
383 #ifdef CONFIG_NUMA
384 	int		numa_node;	/* NUMA node this device is close to */
385 #endif
386 	u64		*dma_mask;	/* dma mask (if dma'able device) */
387 	u64		coherent_dma_mask;/* Like dma_mask, but for
388 					     alloc_coherent mappings as
389 					     not all hardware supports
390 					     64 bit addresses for consistent
391 					     allocations such descriptors. */
392 
393 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
394 
395 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
396 					     override */
397 	/* arch specific additions */
398 	struct dev_archdata	archdata;
399 
400 	/* class_device migration path */
401 	struct list_head	node;
402 	struct class		*class;
403 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
404 	struct attribute_group	**groups;	/* optional groups */
405 	int			uevent_suppress;
406 
407 	void	(*release)(struct device * dev);
408 };
409 
410 #ifdef CONFIG_NUMA
411 static inline int dev_to_node(struct device *dev)
412 {
413 	return dev->numa_node;
414 }
415 static inline void set_dev_node(struct device *dev, int node)
416 {
417 	dev->numa_node = node;
418 }
419 #else
420 static inline int dev_to_node(struct device *dev)
421 {
422 	return -1;
423 }
424 static inline void set_dev_node(struct device *dev, int node)
425 {
426 }
427 #endif
428 
429 static inline void *
430 dev_get_drvdata (struct device *dev)
431 {
432 	return dev->driver_data;
433 }
434 
435 static inline void
436 dev_set_drvdata (struct device *dev, void *data)
437 {
438 	dev->driver_data = data;
439 }
440 
441 static inline int device_is_registered(struct device *dev)
442 {
443 	return dev->is_registered;
444 }
445 
446 void driver_init(void);
447 
448 /*
449  * High level routines for use by the bus drivers
450  */
451 extern int __must_check device_register(struct device * dev);
452 extern void device_unregister(struct device * dev);
453 extern void device_initialize(struct device * dev);
454 extern int __must_check device_add(struct device * dev);
455 extern void device_del(struct device * dev);
456 extern int device_for_each_child(struct device *, void *,
457 		     int (*fn)(struct device *, void *));
458 extern struct device *device_find_child(struct device *, void *data,
459 					int (*match)(struct device *, void *));
460 extern int device_rename(struct device *dev, char *new_name);
461 extern int device_move(struct device *dev, struct device *new_parent);
462 
463 /*
464  * Manual binding of a device to driver. See drivers/base/bus.c
465  * for information on use.
466  */
467 extern int __must_check device_bind_driver(struct device *dev);
468 extern void device_release_driver(struct device * dev);
469 extern int  __must_check device_attach(struct device * dev);
470 extern int __must_check driver_attach(struct device_driver *drv);
471 extern int __must_check device_reprobe(struct device *dev);
472 
473 /*
474  * Easy functions for dynamically creating devices on the fly
475  */
476 extern struct device *device_create(struct class *cls, struct device *parent,
477 				    dev_t devt, const char *fmt, ...)
478 				    __attribute__((format(printf,4,5)));
479 extern void device_destroy(struct class *cls, dev_t devt);
480 
481 /*
482  * Platform "fixup" functions - allow the platform to have their say
483  * about devices and actions that the general device layer doesn't
484  * know about.
485  */
486 /* Notify platform of device discovery */
487 extern int (*platform_notify)(struct device * dev);
488 
489 extern int (*platform_notify_remove)(struct device * dev);
490 
491 
492 /**
493  * get_device - atomically increment the reference count for the device.
494  *
495  */
496 extern struct device * get_device(struct device * dev);
497 extern void put_device(struct device * dev);
498 
499 
500 /* drivers/base/power/shutdown.c */
501 extern void device_shutdown(void);
502 
503 
504 /* drivers/base/firmware.c */
505 extern int __must_check firmware_register(struct subsystem *);
506 extern void firmware_unregister(struct subsystem *);
507 
508 /* debugging and troubleshooting/diagnostic helpers. */
509 extern const char *dev_driver_string(struct device *dev);
510 #define dev_printk(level, dev, format, arg...)	\
511 	printk(level "%s %s: " format , dev_driver_string(dev) , (dev)->bus_id , ## arg)
512 
513 #ifdef DEBUG
514 #define dev_dbg(dev, format, arg...)		\
515 	dev_printk(KERN_DEBUG , dev , format , ## arg)
516 #else
517 #define dev_dbg(dev, format, arg...) do { (void)(dev); } while (0)
518 #endif
519 
520 #define dev_err(dev, format, arg...)		\
521 	dev_printk(KERN_ERR , dev , format , ## arg)
522 #define dev_info(dev, format, arg...)		\
523 	dev_printk(KERN_INFO , dev , format , ## arg)
524 #define dev_warn(dev, format, arg...)		\
525 	dev_printk(KERN_WARNING , dev , format , ## arg)
526 #define dev_notice(dev, format, arg...)		\
527 	dev_printk(KERN_NOTICE , dev , format , ## arg)
528 
529 /* Create alias, so I can be autoloaded. */
530 #define MODULE_ALIAS_CHARDEV(major,minor) \
531 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
532 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
533 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
534 #endif /* _DEVICE_H_ */
535