xref: /linux-6.15/include/linux/device.h (revision 18c99362)
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 <linux/semaphore.h>
24 #include <asm/atomic.h>
25 #include <asm/device.h>
26 
27 #define DEVICE_NAME_SIZE	50
28 /* DEVICE_NAME_HALF is really less than half to accommodate slop */
29 #define DEVICE_NAME_HALF	__stringify(20)
30 #define DEVICE_ID_SIZE		32
31 #define BUS_ID_SIZE		KOBJ_NAME_LEN
32 
33 
34 struct device;
35 struct device_driver;
36 struct driver_private;
37 struct class;
38 struct bus_type;
39 struct bus_type_private;
40 
41 struct bus_attribute {
42 	struct attribute	attr;
43 	ssize_t (*show)(struct bus_type *bus, char *buf);
44 	ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
45 };
46 
47 #define BUS_ATTR(_name, _mode, _show, _store)	\
48 struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)
49 
50 extern int __must_check bus_create_file(struct bus_type *,
51 					struct bus_attribute *);
52 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
53 
54 struct bus_type {
55 	const char		*name;
56 	struct bus_attribute	*bus_attrs;
57 	struct device_attribute	*dev_attrs;
58 	struct driver_attribute	*drv_attrs;
59 
60 	int (*match)(struct device *dev, struct device_driver *drv);
61 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
62 	int (*probe)(struct device *dev);
63 	int (*remove)(struct device *dev);
64 	void (*shutdown)(struct device *dev);
65 
66 	int (*suspend)(struct device *dev, pm_message_t state);
67 	int (*suspend_late)(struct device *dev, pm_message_t state);
68 	int (*resume_early)(struct device *dev);
69 	int (*resume)(struct device *dev);
70 
71 	struct pm_ext_ops *pm;
72 
73 	struct bus_type_private *p;
74 };
75 
76 extern int __must_check bus_register(struct bus_type *bus);
77 extern void bus_unregister(struct bus_type *bus);
78 
79 extern int __must_check bus_rescan_devices(struct bus_type *bus);
80 
81 /* iterator helpers for buses */
82 
83 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
84 		     int (*fn)(struct device *dev, void *data));
85 struct device *bus_find_device(struct bus_type *bus, struct device *start,
86 			       void *data,
87 			       int (*match)(struct device *dev, void *data));
88 struct device *bus_find_device_by_name(struct bus_type *bus,
89 				       struct device *start,
90 				       const char *name);
91 
92 int __must_check bus_for_each_drv(struct bus_type *bus,
93 				  struct device_driver *start, void *data,
94 				  int (*fn)(struct device_driver *, void *));
95 
96 /*
97  * Bus notifiers: Get notified of addition/removal of devices
98  * and binding/unbinding of drivers to devices.
99  * In the long run, it should be a replacement for the platform
100  * notify hooks.
101  */
102 struct notifier_block;
103 
104 extern int bus_register_notifier(struct bus_type *bus,
105 				 struct notifier_block *nb);
106 extern int bus_unregister_notifier(struct bus_type *bus,
107 				   struct notifier_block *nb);
108 
109 /* All 4 notifers below get called with the target struct device *
110  * as an argument. Note that those functions are likely to be called
111  * with the device semaphore held in the core, so be careful.
112  */
113 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
114 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device removed */
115 #define BUS_NOTIFY_BOUND_DRIVER		0x00000003 /* driver bound to device */
116 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000004 /* driver about to be
117 						      unbound */
118 
119 extern struct kset *bus_get_kset(struct bus_type *bus);
120 extern struct klist *bus_get_device_klist(struct bus_type *bus);
121 
122 struct device_driver {
123 	const char		*name;
124 	struct bus_type		*bus;
125 
126 	struct module		*owner;
127 	const char 		*mod_name;	/* used for built-in modules */
128 
129 	int (*probe) (struct device *dev);
130 	int (*remove) (struct device *dev);
131 	void (*shutdown) (struct device *dev);
132 	int (*suspend) (struct device *dev, pm_message_t state);
133 	int (*resume) (struct device *dev);
134 	struct attribute_group **groups;
135 
136 	struct pm_ops *pm;
137 
138 	struct driver_private *p;
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,
148 					 struct bus_type *bus);
149 extern int driver_probe_done(void);
150 
151 /* sysfs interface for exporting driver attributes */
152 
153 struct driver_attribute {
154 	struct attribute attr;
155 	ssize_t (*show)(struct device_driver *driver, char *buf);
156 	ssize_t (*store)(struct device_driver *driver, const char *buf,
157 			 size_t count);
158 };
159 
160 #define DRIVER_ATTR(_name, _mode, _show, _store)	\
161 struct driver_attribute driver_attr_##_name =		\
162 	__ATTR(_name, _mode, _show, _store)
163 
164 extern int __must_check driver_create_file(struct device_driver *driver,
165 					   struct driver_attribute *attr);
166 extern void driver_remove_file(struct device_driver *driver,
167 			       struct driver_attribute *attr);
168 
169 extern int __must_check driver_add_kobj(struct device_driver *drv,
170 					struct kobject *kobj,
171 					const char *fmt, ...);
172 
173 extern int __must_check driver_for_each_device(struct device_driver *drv,
174 					       struct device *start,
175 					       void *data,
176 					       int (*fn)(struct device *dev,
177 							 void *));
178 struct device *driver_find_device(struct device_driver *drv,
179 				  struct device *start, void *data,
180 				  int (*match)(struct device *dev, void *data));
181 
182 /*
183  * device classes
184  */
185 struct class {
186 	const char		*name;
187 	struct module		*owner;
188 
189 	struct kset		subsys;
190 	struct list_head	devices;
191 	struct list_head	interfaces;
192 	struct kset		class_dirs;
193 	struct semaphore	sem; /* locks children, devices, interfaces */
194 	struct class_attribute		*class_attrs;
195 	struct device_attribute		*dev_attrs;
196 
197 	int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
198 
199 	void (*class_release)(struct class *class);
200 	void (*dev_release)(struct device *dev);
201 
202 	int (*suspend)(struct device *dev, pm_message_t state);
203 	int (*resume)(struct device *dev);
204 
205 	struct pm_ops *pm;
206 };
207 
208 extern int __must_check class_register(struct class *class);
209 extern void class_unregister(struct class *class);
210 extern int class_for_each_device(struct class *class, void *data,
211 				 int (*fn)(struct device *dev, void *data));
212 extern struct device *class_find_device(struct class *class, void *data,
213 					int (*match)(struct device *, void *));
214 
215 struct class_attribute {
216 	struct attribute attr;
217 	ssize_t (*show)(struct class *class, char *buf);
218 	ssize_t (*store)(struct class *class, const char *buf, size_t count);
219 };
220 
221 #define CLASS_ATTR(_name, _mode, _show, _store)			\
222 struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
223 
224 extern int __must_check class_create_file(struct class *class,
225 					  const struct class_attribute *attr);
226 extern void class_remove_file(struct class *class,
227 			      const struct class_attribute *attr);
228 
229 struct class_interface {
230 	struct list_head	node;
231 	struct class		*class;
232 
233 	int (*add_dev)		(struct device *, struct class_interface *);
234 	void (*remove_dev)	(struct device *, struct class_interface *);
235 };
236 
237 extern int __must_check class_interface_register(struct class_interface *);
238 extern void class_interface_unregister(struct class_interface *);
239 
240 extern struct class *class_create(struct module *owner, const char *name);
241 extern void class_destroy(struct class *cls);
242 
243 /*
244  * The type of device, "struct device" is embedded in. A class
245  * or bus can contain devices of different types
246  * like "partitions" and "disks", "mouse" and "event".
247  * This identifies the device type and carries type-specific
248  * information, equivalent to the kobj_type of a kobject.
249  * If "name" is specified, the uevent will contain it in
250  * the DEVTYPE variable.
251  */
252 struct device_type {
253 	const char *name;
254 	struct attribute_group **groups;
255 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
256 	void (*release)(struct device *dev);
257 
258 	int (*suspend)(struct device *dev, pm_message_t state);
259 	int (*resume)(struct device *dev);
260 
261 	struct pm_ops *pm;
262 };
263 
264 /* interface for exporting device attributes */
265 struct device_attribute {
266 	struct attribute	attr;
267 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
268 			char *buf);
269 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
270 			 const char *buf, size_t count);
271 };
272 
273 #define DEVICE_ATTR(_name, _mode, _show, _store) \
274 struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
275 
276 extern int __must_check device_create_file(struct device *device,
277 					   struct device_attribute *entry);
278 extern void device_remove_file(struct device *dev,
279 			       struct device_attribute *attr);
280 extern int __must_check device_create_bin_file(struct device *dev,
281 					       struct bin_attribute *attr);
282 extern void device_remove_bin_file(struct device *dev,
283 				   struct bin_attribute *attr);
284 extern int device_schedule_callback_owner(struct device *dev,
285 		void (*func)(struct device *dev), struct module *owner);
286 
287 /* This is a macro to avoid include problems with THIS_MODULE */
288 #define device_schedule_callback(dev, func)			\
289 	device_schedule_callback_owner(dev, func, THIS_MODULE)
290 
291 /* device resource management */
292 typedef void (*dr_release_t)(struct device *dev, void *res);
293 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
294 
295 #ifdef CONFIG_DEBUG_DEVRES
296 extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
297 			     const char *name);
298 #define devres_alloc(release, size, gfp) \
299 	__devres_alloc(release, size, gfp, #release)
300 #else
301 extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
302 #endif
303 extern void devres_free(void *res);
304 extern void devres_add(struct device *dev, void *res);
305 extern void *devres_find(struct device *dev, dr_release_t release,
306 			 dr_match_t match, void *match_data);
307 extern void *devres_get(struct device *dev, void *new_res,
308 			dr_match_t match, void *match_data);
309 extern void *devres_remove(struct device *dev, dr_release_t release,
310 			   dr_match_t match, void *match_data);
311 extern int devres_destroy(struct device *dev, dr_release_t release,
312 			  dr_match_t match, void *match_data);
313 
314 /* devres group */
315 extern void * __must_check devres_open_group(struct device *dev, void *id,
316 					     gfp_t gfp);
317 extern void devres_close_group(struct device *dev, void *id);
318 extern void devres_remove_group(struct device *dev, void *id);
319 extern int devres_release_group(struct device *dev, void *id);
320 
321 /* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
322 extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
323 extern void devm_kfree(struct device *dev, void *p);
324 
325 struct device_dma_parameters {
326 	/*
327 	 * a low level driver may set these to teach IOMMU code about
328 	 * sg limitations.
329 	 */
330 	unsigned int max_segment_size;
331 	unsigned long segment_boundary_mask;
332 };
333 
334 struct device {
335 	struct klist		klist_children;
336 	struct klist_node	knode_parent;	/* node in sibling list */
337 	struct klist_node	knode_driver;
338 	struct klist_node	knode_bus;
339 	struct device		*parent;
340 
341 	struct kobject kobj;
342 	char	bus_id[BUS_ID_SIZE];	/* position on parent bus */
343 	struct device_type	*type;
344 	unsigned		uevent_suppress:1;
345 
346 	struct semaphore	sem;	/* semaphore to synchronize calls to
347 					 * its driver.
348 					 */
349 
350 	struct bus_type	*bus;		/* type of bus device is on */
351 	struct device_driver *driver;	/* which driver has allocated this
352 					   device */
353 	void		*driver_data;	/* data private to the driver */
354 	void		*platform_data;	/* Platform specific data, device
355 					   core doesn't touch it */
356 	struct dev_pm_info	power;
357 
358 #ifdef CONFIG_NUMA
359 	int		numa_node;	/* NUMA node this device is close to */
360 #endif
361 	u64		*dma_mask;	/* dma mask (if dma'able device) */
362 	u64		coherent_dma_mask;/* Like dma_mask, but for
363 					     alloc_coherent mappings as
364 					     not all hardware supports
365 					     64 bit addresses for consistent
366 					     allocations such descriptors. */
367 
368 	struct device_dma_parameters *dma_parms;
369 
370 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
371 
372 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
373 					     override */
374 	/* arch specific additions */
375 	struct dev_archdata	archdata;
376 
377 	spinlock_t		devres_lock;
378 	struct list_head	devres_head;
379 
380 	struct list_head	node;
381 	struct class		*class;
382 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
383 	struct attribute_group	**groups;	/* optional groups */
384 
385 	void	(*release)(struct device *dev);
386 };
387 
388 /* Get the wakeup routines, which depend on struct device */
389 #include <linux/pm_wakeup.h>
390 
391 static inline const char *dev_name(struct device *dev)
392 {
393 	/* will be changed into kobject_name(&dev->kobj) in the near future */
394 	return dev->bus_id;
395 }
396 
397 extern int dev_set_name(struct device *dev, const char *name, ...)
398 			__attribute__((format(printf, 2, 3)));
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 *dev_get_drvdata(struct device *dev)
420 {
421 	return dev->driver_data;
422 }
423 
424 static inline void dev_set_drvdata(struct device *dev, void *data)
425 {
426 	dev->driver_data = data;
427 }
428 
429 static inline int device_is_registered(struct device *dev)
430 {
431 	return dev->kobj.state_in_sysfs;
432 }
433 
434 void driver_init(void);
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 *dev, void *data,
445 		     int (*fn)(struct device *dev, void *data));
446 extern struct device *device_find_child(struct device *dev, void *data,
447 				int (*match)(struct device *dev, void *data));
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_vargs(struct class *cls,
465 					  struct device *parent,
466 					  dev_t devt,
467 					  void *drvdata,
468 					  const char *fmt,
469 					  va_list vargs);
470 extern struct device *device_create(struct class *cls, struct device *parent,
471 				    dev_t devt, const char *fmt, ...)
472 				    __attribute__((format(printf, 4, 5)));
473 extern struct device *device_create_drvdata(struct class *cls,
474 					    struct device *parent,
475 					    dev_t devt,
476 					    void *drvdata,
477 					    const char *fmt, ...)
478 				    __attribute__((format(printf, 5, 6)));
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 /* drivers/base/sys.c */
504 extern void sysdev_shutdown(void);
505 
506 /* debugging and troubleshooting/diagnostic helpers. */
507 extern const char *dev_driver_string(struct device *dev);
508 #define dev_printk(level, dev, format, arg...)	\
509 	printk(level "%s %s: " format , dev_driver_string(dev) , \
510 	       dev_name(dev) , ## arg)
511 
512 #define dev_emerg(dev, format, arg...)		\
513 	dev_printk(KERN_EMERG , dev , format , ## arg)
514 #define dev_alert(dev, format, arg...)		\
515 	dev_printk(KERN_ALERT , dev , format , ## arg)
516 #define dev_crit(dev, format, arg...)		\
517 	dev_printk(KERN_CRIT , dev , format , ## arg)
518 #define dev_err(dev, format, arg...)		\
519 	dev_printk(KERN_ERR , dev , format , ## arg)
520 #define dev_warn(dev, format, arg...)		\
521 	dev_printk(KERN_WARNING , dev , format , ## arg)
522 #define dev_notice(dev, format, arg...)		\
523 	dev_printk(KERN_NOTICE , dev , format , ## arg)
524 #define dev_info(dev, format, arg...)		\
525 	dev_printk(KERN_INFO , dev , format , ## arg)
526 
527 #ifdef DEBUG
528 #define dev_dbg(dev, format, arg...)		\
529 	dev_printk(KERN_DEBUG , dev , format , ## arg)
530 #else
531 #define dev_dbg(dev, format, arg...)		\
532 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
533 #endif
534 
535 #ifdef VERBOSE_DEBUG
536 #define dev_vdbg	dev_dbg
537 #else
538 
539 #define dev_vdbg(dev, format, arg...)		\
540 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
541 #endif
542 
543 /* Create alias, so I can be autoloaded. */
544 #define MODULE_ALIAS_CHARDEV(major,minor) \
545 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
546 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
547 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
548 #endif /* _DEVICE_H_ */
549