xref: /linux-6.15/include/linux/device.h (revision 606d099c)
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 
130 	int	(*probe)	(struct device * dev);
131 	int	(*remove)	(struct device * dev);
132 	void	(*shutdown)	(struct device * dev);
133 	int	(*suspend)	(struct device * dev, pm_message_t state);
134 	int	(*resume)	(struct device * dev);
135 
136 	unsigned int multithread_probe:1;
137 };
138 
139 
140 extern int __must_check driver_register(struct device_driver * drv);
141 extern void driver_unregister(struct device_driver * drv);
142 
143 extern struct device_driver * get_driver(struct device_driver * drv);
144 extern void put_driver(struct device_driver * drv);
145 extern struct device_driver *driver_find(const char *name, struct bus_type *bus);
146 extern int driver_probe_done(void);
147 
148 /* driverfs interface for exporting driver attributes */
149 
150 struct driver_attribute {
151 	struct attribute	attr;
152 	ssize_t (*show)(struct device_driver *, char * buf);
153 	ssize_t (*store)(struct device_driver *, const char * buf, size_t count);
154 };
155 
156 #define DRIVER_ATTR(_name,_mode,_show,_store)	\
157 struct driver_attribute driver_attr_##_name = __ATTR(_name,_mode,_show,_store)
158 
159 extern int __must_check driver_create_file(struct device_driver *,
160 					struct driver_attribute *);
161 extern void driver_remove_file(struct device_driver *, struct driver_attribute *);
162 
163 extern int __must_check driver_for_each_device(struct device_driver * drv,
164 		struct device *start, void *data,
165 		int (*fn)(struct device *, void *));
166 struct device * driver_find_device(struct device_driver *drv,
167 				   struct device *start, void *data,
168 				   int (*match)(struct device *, void *));
169 
170 /*
171  * device classes
172  */
173 struct class {
174 	const char		* name;
175 	struct module		* owner;
176 
177 	struct subsystem	subsys;
178 	struct list_head	children;
179 	struct list_head	devices;
180 	struct list_head	interfaces;
181 	struct semaphore	sem;	/* locks both the children and interfaces lists */
182 
183 	struct kobject		*virtual_dir;
184 
185 	struct class_attribute		* class_attrs;
186 	struct class_device_attribute	* class_dev_attrs;
187 	struct device_attribute		* dev_attrs;
188 
189 	int	(*uevent)(struct class_device *dev, char **envp,
190 			   int num_envp, char *buffer, int buffer_size);
191 	int	(*dev_uevent)(struct device *dev, char **envp, int num_envp,
192 				char *buffer, int buffer_size);
193 
194 	void	(*release)(struct class_device *dev);
195 	void	(*class_release)(struct class *class);
196 	void	(*dev_release)(struct device *dev);
197 
198 	int	(*suspend)(struct device *, pm_message_t state);
199 	int	(*resume)(struct device *);
200 };
201 
202 extern int __must_check class_register(struct class *);
203 extern void class_unregister(struct class *);
204 
205 
206 struct class_attribute {
207 	struct attribute	attr;
208 	ssize_t (*show)(struct class *, char * buf);
209 	ssize_t (*store)(struct class *, const char * buf, size_t count);
210 };
211 
212 #define CLASS_ATTR(_name,_mode,_show,_store)			\
213 struct class_attribute class_attr_##_name = __ATTR(_name,_mode,_show,_store)
214 
215 extern int __must_check class_create_file(struct class *,
216 					const struct class_attribute *);
217 extern void class_remove_file(struct class *, const struct class_attribute *);
218 
219 struct class_device_attribute {
220 	struct attribute	attr;
221 	ssize_t (*show)(struct class_device *, char * buf);
222 	ssize_t (*store)(struct class_device *, const char * buf, size_t count);
223 };
224 
225 #define CLASS_DEVICE_ATTR(_name,_mode,_show,_store)		\
226 struct class_device_attribute class_device_attr_##_name = 	\
227 	__ATTR(_name,_mode,_show,_store)
228 
229 extern int __must_check class_device_create_file(struct class_device *,
230 				    const struct class_device_attribute *);
231 
232 /**
233  * struct class_device - class devices
234  * @class: pointer to the parent class for this class device.  This is required.
235  * @devt: for internal use by the driver core only.
236  * @node: for internal use by the driver core only.
237  * @kobj: for internal use by the driver core only.
238  * @devt_attr: for internal use by the driver core only.
239  * @groups: optional additional groups to be created
240  * @dev: if set, a symlink to the struct device is created in the sysfs
241  * directory for this struct class device.
242  * @class_data: pointer to whatever you want to store here for this struct
243  * class_device.  Use class_get_devdata() and class_set_devdata() to get and
244  * set this pointer.
245  * @parent: pointer to a struct class_device that is the parent of this struct
246  * class_device.  If NULL, this class_device will show up at the root of the
247  * struct class in sysfs (which is probably what you want to have happen.)
248  * @release: pointer to a release function for this struct class_device.  If
249  * set, this will be called instead of the class specific release function.
250  * Only use this if you want to override the default release function, like
251  * when you are nesting class_device structures.
252  * @uevent: pointer to a uevent function for this struct class_device.  If
253  * set, this will be called instead of the class specific uevent function.
254  * Only use this if you want to override the default uevent function, like
255  * when you are nesting class_device structures.
256  */
257 struct class_device {
258 	struct list_head	node;
259 
260 	struct kobject		kobj;
261 	struct class		* class;	/* required */
262 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
263 	struct class_device_attribute *devt_attr;
264 	struct class_device_attribute uevent_attr;
265 	struct device		* dev;		/* not necessary, but nice to have */
266 	void			* class_data;	/* class-specific data */
267 	struct class_device	*parent;	/* parent of this child device, if there is one */
268 	struct attribute_group  ** groups;	/* optional groups */
269 
270 	void	(*release)(struct class_device *dev);
271 	int	(*uevent)(struct class_device *dev, char **envp,
272 			   int num_envp, char *buffer, int buffer_size);
273 	char	class_id[BUS_ID_SIZE];	/* unique to this class */
274 };
275 
276 static inline void *
277 class_get_devdata (struct class_device *dev)
278 {
279 	return dev->class_data;
280 }
281 
282 static inline void
283 class_set_devdata (struct class_device *dev, void *data)
284 {
285 	dev->class_data = data;
286 }
287 
288 
289 extern int __must_check class_device_register(struct class_device *);
290 extern void class_device_unregister(struct class_device *);
291 extern void class_device_initialize(struct class_device *);
292 extern int __must_check class_device_add(struct class_device *);
293 extern void class_device_del(struct class_device *);
294 
295 extern int class_device_rename(struct class_device *, char *);
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 /* interface for exporting device attributes */
331 struct device_attribute {
332 	struct attribute	attr;
333 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
334 			char *buf);
335 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
336 			 const char *buf, size_t count);
337 };
338 
339 #define DEVICE_ATTR(_name,_mode,_show,_store) \
340 struct device_attribute dev_attr_##_name = __ATTR(_name,_mode,_show,_store)
341 
342 extern int __must_check device_create_file(struct device *device,
343 					struct device_attribute * entry);
344 extern void device_remove_file(struct device * dev, struct device_attribute * attr);
345 extern int __must_check device_create_bin_file(struct device *dev,
346 					       struct bin_attribute *attr);
347 extern void device_remove_bin_file(struct device *dev,
348 				   struct bin_attribute *attr);
349 struct device {
350 	struct klist		klist_children;
351 	struct klist_node	knode_parent;		/* node in sibling list */
352 	struct klist_node	knode_driver;
353 	struct klist_node	knode_bus;
354 	struct device 	* parent;
355 
356 	struct kobject kobj;
357 	char	bus_id[BUS_ID_SIZE];	/* position on parent bus */
358 	unsigned		is_registered:1;
359 	struct device_attribute uevent_attr;
360 	struct device_attribute *devt_attr;
361 
362 	struct semaphore	sem;	/* semaphore to synchronize calls to
363 					 * its driver.
364 					 */
365 
366 	struct bus_type	* bus;		/* type of bus device is on */
367 	struct device_driver *driver;	/* which driver has allocated this
368 					   device */
369 	void		*driver_data;	/* data private to the driver */
370 	void		*platform_data;	/* Platform specific data, device
371 					   core doesn't touch it */
372 	struct dev_pm_info	power;
373 
374 #ifdef CONFIG_NUMA
375 	int		numa_node;	/* NUMA node this device is close to */
376 #endif
377 	u64		*dma_mask;	/* dma mask (if dma'able device) */
378 	u64		coherent_dma_mask;/* Like dma_mask, but for
379 					     alloc_coherent mappings as
380 					     not all hardware supports
381 					     64 bit addresses for consistent
382 					     allocations such descriptors. */
383 
384 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
385 
386 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
387 					     override */
388 	/* arch specific additions */
389 	struct dev_archdata	archdata;
390 
391 	/* class_device migration path */
392 	struct list_head	node;
393 	struct class		*class;		/* optional*/
394 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
395 	struct attribute_group	**groups;	/* optional groups */
396 
397 	void	(*release)(struct device * dev);
398 };
399 
400 #ifdef CONFIG_NUMA
401 static inline int dev_to_node(struct device *dev)
402 {
403 	return dev->numa_node;
404 }
405 static inline void set_dev_node(struct device *dev, int node)
406 {
407 	dev->numa_node = node;
408 }
409 #else
410 static inline int dev_to_node(struct device *dev)
411 {
412 	return -1;
413 }
414 static inline void set_dev_node(struct device *dev, int node)
415 {
416 }
417 #endif
418 
419 static inline void *
420 dev_get_drvdata (struct device *dev)
421 {
422 	return dev->driver_data;
423 }
424 
425 static inline void
426 dev_set_drvdata (struct device *dev, void *data)
427 {
428 	dev->driver_data = data;
429 }
430 
431 static inline int device_is_registered(struct device *dev)
432 {
433 	return dev->is_registered;
434 }
435 
436 /*
437  * High level routines for use by the bus drivers
438  */
439 extern int __must_check device_register(struct device * dev);
440 extern void device_unregister(struct device * dev);
441 extern void device_initialize(struct device * dev);
442 extern int __must_check device_add(struct device * dev);
443 extern void device_del(struct device * dev);
444 extern int device_for_each_child(struct device *, void *,
445 		     int (*fn)(struct device *, void *));
446 extern struct device *device_find_child(struct device *, void *data,
447 					int (*match)(struct device *, void *));
448 extern int device_rename(struct device *dev, char *new_name);
449 extern int device_move(struct device *dev, struct device *new_parent);
450 
451 /*
452  * Manual binding of a device to driver. See drivers/base/bus.c
453  * for information on use.
454  */
455 extern int __must_check device_bind_driver(struct device *dev);
456 extern void device_release_driver(struct device * dev);
457 extern int  __must_check device_attach(struct device * dev);
458 extern int __must_check driver_attach(struct device_driver *drv);
459 extern int __must_check device_reprobe(struct device *dev);
460 
461 /*
462  * Easy functions for dynamically creating devices on the fly
463  */
464 extern struct device *device_create(struct class *cls, struct device *parent,
465 				    dev_t devt, const char *fmt, ...)
466 				    __attribute__((format(printf,4,5)));
467 extern void device_destroy(struct class *cls, dev_t devt);
468 
469 /*
470  * Platform "fixup" functions - allow the platform to have their say
471  * about devices and actions that the general device layer doesn't
472  * know about.
473  */
474 /* Notify platform of device discovery */
475 extern int (*platform_notify)(struct device * dev);
476 
477 extern int (*platform_notify_remove)(struct device * dev);
478 
479 
480 /**
481  * get_device - atomically increment the reference count for the device.
482  *
483  */
484 extern struct device * get_device(struct device * dev);
485 extern void put_device(struct device * dev);
486 
487 
488 /* drivers/base/power/shutdown.c */
489 extern void device_shutdown(void);
490 
491 
492 /* drivers/base/firmware.c */
493 extern int __must_check firmware_register(struct subsystem *);
494 extern void firmware_unregister(struct subsystem *);
495 
496 /* debugging and troubleshooting/diagnostic helpers. */
497 extern const char *dev_driver_string(struct device *dev);
498 #define dev_printk(level, dev, format, arg...)	\
499 	printk(level "%s %s: " format , dev_driver_string(dev) , (dev)->bus_id , ## arg)
500 
501 #ifdef DEBUG
502 #define dev_dbg(dev, format, arg...)		\
503 	dev_printk(KERN_DEBUG , dev , format , ## arg)
504 #else
505 #define dev_dbg(dev, format, arg...) do { (void)(dev); } while (0)
506 #endif
507 
508 #define dev_err(dev, format, arg...)		\
509 	dev_printk(KERN_ERR , dev , format , ## arg)
510 #define dev_info(dev, format, arg...)		\
511 	dev_printk(KERN_INFO , dev , format , ## arg)
512 #define dev_warn(dev, format, arg...)		\
513 	dev_printk(KERN_WARNING , dev , format , ## arg)
514 #define dev_notice(dev, format, arg...)		\
515 	dev_printk(KERN_NOTICE , dev , format , ## arg)
516 
517 /* Create alias, so I can be autoloaded. */
518 #define MODULE_ALIAS_CHARDEV(major,minor) \
519 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
520 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
521 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
522 #endif /* _DEVICE_H_ */
523