xref: /linux-6.15/include/linux/device.h (revision 2d6ffcca)
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/lockdep.h>
20 #include <linux/compiler.h>
21 #include <linux/types.h>
22 #include <linux/module.h>
23 #include <linux/pm.h>
24 #include <linux/semaphore.h>
25 #include <asm/atomic.h>
26 #include <asm/device.h>
27 
28 #define BUS_ID_SIZE		20
29 
30 struct device;
31 struct device_driver;
32 struct driver_private;
33 struct class;
34 struct class_private;
35 struct bus_type;
36 struct bus_type_private;
37 
38 struct bus_attribute {
39 	struct attribute	attr;
40 	ssize_t (*show)(struct bus_type *bus, char *buf);
41 	ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
42 };
43 
44 #define BUS_ATTR(_name, _mode, _show, _store)	\
45 struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)
46 
47 extern int __must_check bus_create_file(struct bus_type *,
48 					struct bus_attribute *);
49 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
50 
51 struct bus_type {
52 	const char		*name;
53 	struct bus_attribute	*bus_attrs;
54 	struct device_attribute	*dev_attrs;
55 	struct driver_attribute	*drv_attrs;
56 
57 	int (*match)(struct device *dev, struct device_driver *drv);
58 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
59 	int (*probe)(struct device *dev);
60 	int (*remove)(struct device *dev);
61 	void (*shutdown)(struct device *dev);
62 
63 	int (*suspend)(struct device *dev, pm_message_t state);
64 	int (*suspend_late)(struct device *dev, pm_message_t state);
65 	int (*resume_early)(struct device *dev);
66 	int (*resume)(struct device *dev);
67 
68 	struct pm_ext_ops *pm;
69 
70 	struct bus_type_private *p;
71 };
72 
73 extern int __must_check bus_register(struct bus_type *bus);
74 extern void bus_unregister(struct bus_type *bus);
75 
76 extern int __must_check bus_rescan_devices(struct bus_type *bus);
77 
78 /* iterator helpers for buses */
79 
80 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
81 		     int (*fn)(struct device *dev, void *data));
82 struct device *bus_find_device(struct bus_type *bus, struct device *start,
83 			       void *data,
84 			       int (*match)(struct device *dev, void *data));
85 struct device *bus_find_device_by_name(struct bus_type *bus,
86 				       struct device *start,
87 				       const char *name);
88 
89 int __must_check bus_for_each_drv(struct bus_type *bus,
90 				  struct device_driver *start, void *data,
91 				  int (*fn)(struct device_driver *, void *));
92 
93 /*
94  * Bus notifiers: Get notified of addition/removal of devices
95  * and binding/unbinding of drivers to devices.
96  * In the long run, it should be a replacement for the platform
97  * notify hooks.
98  */
99 struct notifier_block;
100 
101 extern int bus_register_notifier(struct bus_type *bus,
102 				 struct notifier_block *nb);
103 extern int bus_unregister_notifier(struct bus_type *bus,
104 				   struct notifier_block *nb);
105 
106 /* All 4 notifers below get called with the target struct device *
107  * as an argument. Note that those functions are likely to be called
108  * with the device semaphore held in the core, so be careful.
109  */
110 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
111 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device removed */
112 #define BUS_NOTIFY_BOUND_DRIVER		0x00000003 /* driver bound to device */
113 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000004 /* driver about to be
114 						      unbound */
115 
116 extern struct kset *bus_get_kset(struct bus_type *bus);
117 extern struct klist *bus_get_device_klist(struct bus_type *bus);
118 
119 struct device_driver {
120 	const char		*name;
121 	struct bus_type		*bus;
122 
123 	struct module		*owner;
124 	const char 		*mod_name;	/* used for built-in modules */
125 
126 	int (*probe) (struct device *dev);
127 	int (*remove) (struct device *dev);
128 	void (*shutdown) (struct device *dev);
129 	int (*suspend) (struct device *dev, pm_message_t state);
130 	int (*resume) (struct device *dev);
131 	struct attribute_group **groups;
132 
133 	struct pm_ops *pm;
134 
135 	struct driver_private *p;
136 };
137 
138 
139 extern int __must_check driver_register(struct device_driver *drv);
140 extern void driver_unregister(struct device_driver *drv);
141 
142 extern struct device_driver *get_driver(struct device_driver *drv);
143 extern void put_driver(struct device_driver *drv);
144 extern struct device_driver *driver_find(const char *name,
145 					 struct bus_type *bus);
146 extern int driver_probe_done(void);
147 
148 /* sysfs interface for exporting driver attributes */
149 
150 struct driver_attribute {
151 	struct attribute attr;
152 	ssize_t (*show)(struct device_driver *driver, char *buf);
153 	ssize_t (*store)(struct device_driver *driver, const char *buf,
154 			 size_t count);
155 };
156 
157 #define DRIVER_ATTR(_name, _mode, _show, _store)	\
158 struct driver_attribute driver_attr_##_name =		\
159 	__ATTR(_name, _mode, _show, _store)
160 
161 extern int __must_check driver_create_file(struct device_driver *driver,
162 					   struct driver_attribute *attr);
163 extern void driver_remove_file(struct device_driver *driver,
164 			       struct driver_attribute *attr);
165 
166 extern int __must_check driver_add_kobj(struct device_driver *drv,
167 					struct kobject *kobj,
168 					const char *fmt, ...);
169 
170 extern int __must_check driver_for_each_device(struct device_driver *drv,
171 					       struct device *start,
172 					       void *data,
173 					       int (*fn)(struct device *dev,
174 							 void *));
175 struct device *driver_find_device(struct device_driver *drv,
176 				  struct device *start, void *data,
177 				  int (*match)(struct device *dev, void *data));
178 
179 /*
180  * device classes
181  */
182 struct class {
183 	const char		*name;
184 	struct module		*owner;
185 
186 	struct class_attribute		*class_attrs;
187 	struct device_attribute		*dev_attrs;
188 	struct kobject			*dev_kobj;
189 
190 	int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
191 
192 	void (*class_release)(struct class *class);
193 	void (*dev_release)(struct device *dev);
194 
195 	int (*suspend)(struct device *dev, pm_message_t state);
196 	int (*resume)(struct device *dev);
197 
198 	struct pm_ops *pm;
199 	struct class_private *p;
200 };
201 
202 extern struct kobject *sysfs_dev_block_kobj;
203 extern struct kobject *sysfs_dev_char_kobj;
204 extern int __must_check __class_register(struct class *class,
205 					 struct lock_class_key *key);
206 extern void class_unregister(struct class *class);
207 
208 /* This is a #define to keep the compiler from merging different
209  * instances of the __key variable */
210 #define class_register(class)			\
211 ({						\
212 	static struct lock_class_key __key;	\
213 	__class_register(class, &__key);	\
214 })
215 
216 extern int class_for_each_device(struct class *class, struct device *start,
217 				 void *data,
218 				 int (*fn)(struct device *dev, void *data));
219 extern struct device *class_find_device(struct class *class,
220 					struct device *start, void *data,
221 					int (*match)(struct device *, void *));
222 
223 struct class_attribute {
224 	struct attribute attr;
225 	ssize_t (*show)(struct class *class, char *buf);
226 	ssize_t (*store)(struct class *class, const char *buf, size_t count);
227 };
228 
229 #define CLASS_ATTR(_name, _mode, _show, _store)			\
230 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
231 
232 extern int __must_check class_create_file(struct class *class,
233 					  const struct class_attribute *attr);
234 extern void class_remove_file(struct class *class,
235 			      const struct class_attribute *attr);
236 
237 struct class_interface {
238 	struct list_head	node;
239 	struct class		*class;
240 
241 	int (*add_dev)		(struct device *, struct class_interface *);
242 	void (*remove_dev)	(struct device *, struct class_interface *);
243 };
244 
245 extern int __must_check class_interface_register(struct class_interface *);
246 extern void class_interface_unregister(struct class_interface *);
247 
248 extern struct class * __must_check __class_create(struct module *owner,
249 						  const char *name,
250 						  struct lock_class_key *key);
251 extern void class_destroy(struct class *cls);
252 
253 /* This is a #define to keep the compiler from merging different
254  * instances of the __key variable */
255 #define class_create(owner, name)		\
256 ({						\
257 	static struct lock_class_key __key;	\
258 	__class_create(owner, name, &__key);	\
259 })
260 
261 /*
262  * The type of device, "struct device" is embedded in. A class
263  * or bus can contain devices of different types
264  * like "partitions" and "disks", "mouse" and "event".
265  * This identifies the device type and carries type-specific
266  * information, equivalent to the kobj_type of a kobject.
267  * If "name" is specified, the uevent will contain it in
268  * the DEVTYPE variable.
269  */
270 struct device_type {
271 	const char *name;
272 	struct attribute_group **groups;
273 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
274 	void (*release)(struct device *dev);
275 
276 	int (*suspend)(struct device *dev, pm_message_t state);
277 	int (*resume)(struct device *dev);
278 
279 	struct pm_ops *pm;
280 };
281 
282 /* interface for exporting device attributes */
283 struct device_attribute {
284 	struct attribute	attr;
285 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
286 			char *buf);
287 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
288 			 const char *buf, size_t count);
289 };
290 
291 #define DEVICE_ATTR(_name, _mode, _show, _store) \
292 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
293 
294 extern int __must_check device_create_file(struct device *device,
295 					   struct device_attribute *entry);
296 extern void device_remove_file(struct device *dev,
297 			       struct device_attribute *attr);
298 extern int __must_check device_create_bin_file(struct device *dev,
299 					       struct bin_attribute *attr);
300 extern void device_remove_bin_file(struct device *dev,
301 				   struct bin_attribute *attr);
302 extern int device_schedule_callback_owner(struct device *dev,
303 		void (*func)(struct device *dev), struct module *owner);
304 
305 /* This is a macro to avoid include problems with THIS_MODULE */
306 #define device_schedule_callback(dev, func)			\
307 	device_schedule_callback_owner(dev, func, THIS_MODULE)
308 
309 /* device resource management */
310 typedef void (*dr_release_t)(struct device *dev, void *res);
311 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
312 
313 #ifdef CONFIG_DEBUG_DEVRES
314 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
315 			     const char *name);
316 #define devres_alloc(release, size, gfp) \
317 	__devres_alloc(release, size, gfp, #release)
318 #else
319 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
320 #endif
321 extern void devres_free(void *res);
322 extern void devres_add(struct device *dev, void *res);
323 extern void *devres_find(struct device *dev, dr_release_t release,
324 			 dr_match_t match, void *match_data);
325 extern void *devres_get(struct device *dev, void *new_res,
326 			dr_match_t match, void *match_data);
327 extern void *devres_remove(struct device *dev, dr_release_t release,
328 			   dr_match_t match, void *match_data);
329 extern int devres_destroy(struct device *dev, dr_release_t release,
330 			  dr_match_t match, void *match_data);
331 
332 /* devres group */
333 extern void * __must_check devres_open_group(struct device *dev, void *id,
334 					     gfp_t gfp);
335 extern void devres_close_group(struct device *dev, void *id);
336 extern void devres_remove_group(struct device *dev, void *id);
337 extern int devres_release_group(struct device *dev, void *id);
338 
339 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
340 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
341 extern void devm_kfree(struct device *dev, void *p);
342 
343 struct device_dma_parameters {
344 	/*
345 	 * a low level driver may set these to teach IOMMU code about
346 	 * sg limitations.
347 	 */
348 	unsigned int max_segment_size;
349 	unsigned long segment_boundary_mask;
350 };
351 
352 struct device {
353 	struct klist		klist_children;
354 	struct klist_node	knode_parent;	/* node in sibling list */
355 	struct klist_node	knode_driver;
356 	struct klist_node	knode_bus;
357 	struct device		*parent;
358 
359 	struct kobject kobj;
360 	char	bus_id[BUS_ID_SIZE];	/* position on parent bus */
361 	struct device_type	*type;
362 	unsigned		uevent_suppress:1;
363 
364 	struct semaphore	sem;	/* semaphore to synchronize calls to
365 					 * its driver.
366 					 */
367 
368 	struct bus_type	*bus;		/* type of bus device is on */
369 	struct device_driver *driver;	/* which driver has allocated this
370 					   device */
371 	void		*driver_data;	/* data private to the driver */
372 	void		*platform_data;	/* Platform specific data, device
373 					   core doesn't touch it */
374 	struct dev_pm_info	power;
375 
376 #ifdef CONFIG_NUMA
377 	int		numa_node;	/* NUMA node this device is close to */
378 #endif
379 	u64		*dma_mask;	/* dma mask (if dma'able device) */
380 	u64		coherent_dma_mask;/* Like dma_mask, but for
381 					     alloc_coherent mappings as
382 					     not all hardware supports
383 					     64 bit addresses for consistent
384 					     allocations such descriptors. */
385 
386 	struct device_dma_parameters *dma_parms;
387 
388 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
389 
390 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
391 					     override */
392 	/* arch specific additions */
393 	struct dev_archdata	archdata;
394 
395 	spinlock_t		devres_lock;
396 	struct list_head	devres_head;
397 
398 	struct list_head	node;
399 	struct class		*class;
400 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
401 	struct attribute_group	**groups;	/* optional groups */
402 
403 	void	(*release)(struct device *dev);
404 };
405 
406 /* Get the wakeup routines, which depend on struct device */
407 #include <linux/pm_wakeup.h>
408 
409 static inline const char *dev_name(struct device *dev)
410 {
411 	/* will be changed into kobject_name(&dev->kobj) in the near future */
412 	return dev->bus_id;
413 }
414 
415 extern int dev_set_name(struct device *dev, const char *name, ...)
416 			__attribute__((format(printf, 2, 3)));
417 
418 #ifdef CONFIG_NUMA
419 static inline int dev_to_node(struct device *dev)
420 {
421 	return dev->numa_node;
422 }
423 static inline void set_dev_node(struct device *dev, int node)
424 {
425 	dev->numa_node = node;
426 }
427 #else
428 static inline int dev_to_node(struct device *dev)
429 {
430 	return -1;
431 }
432 static inline void set_dev_node(struct device *dev, int node)
433 {
434 }
435 #endif
436 
437 static inline void *dev_get_drvdata(struct device *dev)
438 {
439 	return dev->driver_data;
440 }
441 
442 static inline void dev_set_drvdata(struct device *dev, void *data)
443 {
444 	dev->driver_data = data;
445 }
446 
447 static inline int device_is_registered(struct device *dev)
448 {
449 	return dev->kobj.state_in_sysfs;
450 }
451 
452 void driver_init(void);
453 
454 /*
455  * High level routines for use by the bus drivers
456  */
457 extern int __must_check device_register(struct device *dev);
458 extern void device_unregister(struct device *dev);
459 extern void device_initialize(struct device *dev);
460 extern int __must_check device_add(struct device *dev);
461 extern void device_del(struct device *dev);
462 extern int device_for_each_child(struct device *dev, void *data,
463 		     int (*fn)(struct device *dev, void *data));
464 extern struct device *device_find_child(struct device *dev, void *data,
465 				int (*match)(struct device *dev, void *data));
466 extern int device_rename(struct device *dev, char *new_name);
467 extern int device_move(struct device *dev, struct device *new_parent);
468 
469 /*
470  * Manual binding of a device to driver. See drivers/base/bus.c
471  * for information on use.
472  */
473 extern int __must_check device_bind_driver(struct device *dev);
474 extern void device_release_driver(struct device *dev);
475 extern int  __must_check device_attach(struct device *dev);
476 extern int __must_check driver_attach(struct device_driver *drv);
477 extern int __must_check device_reprobe(struct device *dev);
478 
479 /*
480  * Easy functions for dynamically creating devices on the fly
481  */
482 extern struct device *device_create_vargs(struct class *cls,
483 					  struct device *parent,
484 					  dev_t devt,
485 					  void *drvdata,
486 					  const char *fmt,
487 					  va_list vargs);
488 extern struct device *device_create(struct class *cls, struct device *parent,
489 				    dev_t devt, void *drvdata,
490 				    const char *fmt, ...)
491 				    __attribute__((format(printf, 5, 6)));
492 #define device_create_drvdata	device_create
493 extern void device_destroy(struct class *cls, dev_t devt);
494 
495 /*
496  * Platform "fixup" functions - allow the platform to have their say
497  * about devices and actions that the general device layer doesn't
498  * know about.
499  */
500 /* Notify platform of device discovery */
501 extern int (*platform_notify)(struct device *dev);
502 
503 extern int (*platform_notify_remove)(struct device *dev);
504 
505 
506 /**
507  * get_device - atomically increment the reference count for the device.
508  *
509  */
510 extern struct device *get_device(struct device *dev);
511 extern void put_device(struct device *dev);
512 
513 
514 /* drivers/base/power/shutdown.c */
515 extern void device_shutdown(void);
516 
517 /* drivers/base/sys.c */
518 extern void sysdev_shutdown(void);
519 
520 /* debugging and troubleshooting/diagnostic helpers. */
521 extern const char *dev_driver_string(struct device *dev);
522 #define dev_printk(level, dev, format, arg...)	\
523 	printk(level "%s %s: " format , dev_driver_string(dev) , \
524 	       dev_name(dev) , ## arg)
525 
526 #define dev_emerg(dev, format, arg...)		\
527 	dev_printk(KERN_EMERG , dev , format , ## arg)
528 #define dev_alert(dev, format, arg...)		\
529 	dev_printk(KERN_ALERT , dev , format , ## arg)
530 #define dev_crit(dev, format, arg...)		\
531 	dev_printk(KERN_CRIT , dev , format , ## arg)
532 #define dev_err(dev, format, arg...)		\
533 	dev_printk(KERN_ERR , dev , format , ## arg)
534 #define dev_warn(dev, format, arg...)		\
535 	dev_printk(KERN_WARNING , dev , format , ## arg)
536 #define dev_notice(dev, format, arg...)		\
537 	dev_printk(KERN_NOTICE , dev , format , ## arg)
538 #define dev_info(dev, format, arg...)		\
539 	dev_printk(KERN_INFO , dev , format , ## arg)
540 
541 #ifdef DEBUG
542 #define dev_dbg(dev, format, arg...)		\
543 	dev_printk(KERN_DEBUG , dev , format , ## arg)
544 #else
545 #define dev_dbg(dev, format, arg...)		\
546 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
547 #endif
548 
549 #ifdef VERBOSE_DEBUG
550 #define dev_vdbg	dev_dbg
551 #else
552 
553 #define dev_vdbg(dev, format, arg...)		\
554 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
555 #endif
556 
557 /* Create alias, so I can be autoloaded. */
558 #define MODULE_ALIAS_CHARDEV(major,minor) \
559 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
560 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
561 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
562 #endif /* _DEVICE_H_ */
563