xref: /linux-6.15/include/linux/device.h (revision de2fe5e0)
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/config.h>
15 #include <linux/ioport.h>
16 #include <linux/kobject.h>
17 #include <linux/klist.h>
18 #include <linux/list.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 
25 #define DEVICE_NAME_SIZE	50
26 #define DEVICE_NAME_HALF	__stringify(20)	/* Less than half to accommodate slop */
27 #define DEVICE_ID_SIZE		32
28 #define BUS_ID_SIZE		KOBJ_NAME_LEN
29 
30 
31 struct device;
32 struct device_driver;
33 struct class;
34 struct class_device;
35 
36 struct bus_type {
37 	const char		* name;
38 
39 	struct subsystem	subsys;
40 	struct kset		drivers;
41 	struct kset		devices;
42 	struct klist		klist_devices;
43 	struct klist		klist_drivers;
44 
45 	struct bus_attribute	* bus_attrs;
46 	struct device_attribute	* dev_attrs;
47 	struct driver_attribute	* drv_attrs;
48 
49 	int		(*match)(struct device * dev, struct device_driver * drv);
50 	int		(*uevent)(struct device *dev, char **envp,
51 				  int num_envp, char *buffer, int buffer_size);
52 	int		(*probe)(struct device * dev);
53 	int		(*remove)(struct device * dev);
54 	void		(*shutdown)(struct device * dev);
55 	int		(*suspend)(struct device * dev, pm_message_t state);
56 	int		(*resume)(struct device * dev);
57 };
58 
59 extern int bus_register(struct bus_type * bus);
60 extern void bus_unregister(struct bus_type * bus);
61 
62 extern void bus_rescan_devices(struct bus_type * bus);
63 
64 extern struct bus_type * get_bus(struct bus_type * bus);
65 extern void put_bus(struct bus_type * bus);
66 
67 extern struct bus_type * find_bus(char * name);
68 
69 /* iterator helpers for buses */
70 
71 int bus_for_each_dev(struct bus_type * bus, struct device * start, void * data,
72 		     int (*fn)(struct device *, void *));
73 struct device * bus_find_device(struct bus_type *bus, struct device *start,
74 				void *data, int (*match)(struct device *, void *));
75 
76 int bus_for_each_drv(struct bus_type * bus, struct device_driver * start,
77 		     void * data, int (*fn)(struct device_driver *, void *));
78 
79 
80 /* driverfs interface for exporting bus attributes */
81 
82 struct bus_attribute {
83 	struct attribute	attr;
84 	ssize_t (*show)(struct bus_type *, char * buf);
85 	ssize_t (*store)(struct bus_type *, const char * buf, size_t count);
86 };
87 
88 #define BUS_ATTR(_name,_mode,_show,_store)	\
89 struct bus_attribute bus_attr_##_name = __ATTR(_name,_mode,_show,_store)
90 
91 extern int bus_create_file(struct bus_type *, struct bus_attribute *);
92 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
93 
94 struct device_driver {
95 	const char		* name;
96 	struct bus_type		* bus;
97 
98 	struct completion	unloaded;
99 	struct kobject		kobj;
100 	struct klist		klist_devices;
101 	struct klist_node	knode_bus;
102 
103 	struct module		* owner;
104 
105 	int	(*probe)	(struct device * dev);
106 	int	(*remove)	(struct device * dev);
107 	void	(*shutdown)	(struct device * dev);
108 	int	(*suspend)	(struct device * dev, pm_message_t state);
109 	int	(*resume)	(struct device * dev);
110 };
111 
112 
113 extern int driver_register(struct device_driver * drv);
114 extern void driver_unregister(struct device_driver * drv);
115 
116 extern struct device_driver * get_driver(struct device_driver * drv);
117 extern void put_driver(struct device_driver * drv);
118 extern struct device_driver *driver_find(const char *name, struct bus_type *bus);
119 
120 
121 /* driverfs interface for exporting driver attributes */
122 
123 struct driver_attribute {
124 	struct attribute	attr;
125 	ssize_t (*show)(struct device_driver *, char * buf);
126 	ssize_t (*store)(struct device_driver *, const char * buf, size_t count);
127 };
128 
129 #define DRIVER_ATTR(_name,_mode,_show,_store)	\
130 struct driver_attribute driver_attr_##_name = __ATTR(_name,_mode,_show,_store)
131 
132 extern int driver_create_file(struct device_driver *, struct driver_attribute *);
133 extern void driver_remove_file(struct device_driver *, struct driver_attribute *);
134 
135 extern int driver_for_each_device(struct device_driver * drv, struct device * start,
136 				  void * data, int (*fn)(struct device *, void *));
137 struct device * driver_find_device(struct device_driver *drv,
138 				   struct device *start, void *data,
139 				   int (*match)(struct device *, void *));
140 
141 
142 /*
143  * device classes
144  */
145 struct class {
146 	const char		* name;
147 	struct module		* owner;
148 
149 	struct subsystem	subsys;
150 	struct list_head	children;
151 	struct list_head	interfaces;
152 	struct semaphore	sem;	/* locks both the children and interfaces lists */
153 
154 	struct class_attribute		* class_attrs;
155 	struct class_device_attribute	* class_dev_attrs;
156 
157 	int	(*uevent)(struct class_device *dev, char **envp,
158 			   int num_envp, char *buffer, int buffer_size);
159 
160 	void	(*release)(struct class_device *dev);
161 	void	(*class_release)(struct class *class);
162 };
163 
164 extern int class_register(struct class *);
165 extern void class_unregister(struct class *);
166 
167 extern struct class * class_get(struct class *);
168 extern void class_put(struct class *);
169 
170 
171 struct class_attribute {
172 	struct attribute	attr;
173 	ssize_t (*show)(struct class *, char * buf);
174 	ssize_t (*store)(struct class *, const char * buf, size_t count);
175 };
176 
177 #define CLASS_ATTR(_name,_mode,_show,_store)			\
178 struct class_attribute class_attr_##_name = __ATTR(_name,_mode,_show,_store)
179 
180 extern int class_create_file(struct class *, const struct class_attribute *);
181 extern void class_remove_file(struct class *, const struct class_attribute *);
182 
183 struct class_device_attribute {
184 	struct attribute	attr;
185 	ssize_t (*show)(struct class_device *, char * buf);
186 	ssize_t (*store)(struct class_device *, const char * buf, size_t count);
187 };
188 
189 #define CLASS_DEVICE_ATTR(_name,_mode,_show,_store)		\
190 struct class_device_attribute class_device_attr_##_name = 	\
191 	__ATTR(_name,_mode,_show,_store)
192 
193 extern int class_device_create_file(struct class_device *,
194 				    const struct class_device_attribute *);
195 
196 /**
197  * struct class_device - class devices
198  * @class: pointer to the parent class for this class device.  This is required.
199  * @devt: for internal use by the driver core only.
200  * @node: for internal use by the driver core only.
201  * @kobj: for internal use by the driver core only.
202  * @devt_attr: for internal use by the driver core only.
203  * @dev: if set, a symlink to the struct device is created in the sysfs
204  * directory for this struct class device.
205  * @class_data: pointer to whatever you want to store here for this struct
206  * class_device.  Use class_get_devdata() and class_set_devdata() to get and
207  * set this pointer.
208  * @parent: pointer to a struct class_device that is the parent of this struct
209  * class_device.  If NULL, this class_device will show up at the root of the
210  * struct class in sysfs (which is probably what you want to have happen.)
211  * @release: pointer to a release function for this struct class_device.  If
212  * set, this will be called instead of the class specific release function.
213  * Only use this if you want to override the default release function, like
214  * when you are nesting class_device structures.
215  * @uevent: pointer to a uevent function for this struct class_device.  If
216  * set, this will be called instead of the class specific uevent function.
217  * Only use this if you want to override the default uevent function, like
218  * when you are nesting class_device structures.
219  */
220 struct class_device {
221 	struct list_head	node;
222 
223 	struct kobject		kobj;
224 	struct class		* class;	/* required */
225 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
226 	struct class_device_attribute *devt_attr;
227 	struct class_device_attribute uevent_attr;
228 	struct device		* dev;		/* not necessary, but nice to have */
229 	void			* class_data;	/* class-specific data */
230 	struct class_device	*parent;	/* parent of this child device, if there is one */
231 
232 	void	(*release)(struct class_device *dev);
233 	int	(*uevent)(struct class_device *dev, char **envp,
234 			   int num_envp, char *buffer, int buffer_size);
235 	char	class_id[BUS_ID_SIZE];	/* unique to this class */
236 };
237 
238 static inline void *
239 class_get_devdata (struct class_device *dev)
240 {
241 	return dev->class_data;
242 }
243 
244 static inline void
245 class_set_devdata (struct class_device *dev, void *data)
246 {
247 	dev->class_data = data;
248 }
249 
250 
251 extern int class_device_register(struct class_device *);
252 extern void class_device_unregister(struct class_device *);
253 extern void class_device_initialize(struct class_device *);
254 extern int class_device_add(struct class_device *);
255 extern void class_device_del(struct class_device *);
256 
257 extern int class_device_rename(struct class_device *, char *);
258 
259 extern struct class_device * class_device_get(struct class_device *);
260 extern void class_device_put(struct class_device *);
261 
262 extern void class_device_remove_file(struct class_device *,
263 				     const struct class_device_attribute *);
264 extern int class_device_create_bin_file(struct class_device *,
265 					struct bin_attribute *);
266 extern void class_device_remove_bin_file(struct class_device *,
267 					 struct bin_attribute *);
268 
269 struct class_interface {
270 	struct list_head	node;
271 	struct class		*class;
272 
273 	int (*add)	(struct class_device *, struct class_interface *);
274 	void (*remove)	(struct class_device *, struct class_interface *);
275 };
276 
277 extern int class_interface_register(struct class_interface *);
278 extern void class_interface_unregister(struct class_interface *);
279 
280 extern struct class *class_create(struct module *owner, char *name);
281 extern void class_destroy(struct class *cls);
282 extern struct class_device *class_device_create(struct class *cls,
283 						struct class_device *parent,
284 						dev_t devt,
285 						struct device *device,
286 						char *fmt, ...)
287 					__attribute__((format(printf,5,6)));
288 extern void class_device_destroy(struct class *cls, dev_t devt);
289 
290 
291 /* interface for exporting device attributes */
292 struct device_attribute {
293 	struct attribute	attr;
294 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
295 			char *buf);
296 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
297 			 const char *buf, size_t count);
298 };
299 
300 #define DEVICE_ATTR(_name,_mode,_show,_store) \
301 struct device_attribute dev_attr_##_name = __ATTR(_name,_mode,_show,_store)
302 
303 extern int device_create_file(struct device *device, struct device_attribute * entry);
304 extern void device_remove_file(struct device * dev, struct device_attribute * attr);
305 struct device {
306 	struct klist		klist_children;
307 	struct klist_node	knode_parent;		/* node in sibling list */
308 	struct klist_node	knode_driver;
309 	struct klist_node	knode_bus;
310 	struct device 	* parent;
311 
312 	struct kobject kobj;
313 	char	bus_id[BUS_ID_SIZE];	/* position on parent bus */
314 	struct device_attribute uevent_attr;
315 
316 	struct semaphore	sem;	/* semaphore to synchronize calls to
317 					 * its driver.
318 					 */
319 
320 	struct bus_type	* bus;		/* type of bus device is on */
321 	struct device_driver *driver;	/* which driver has allocated this
322 					   device */
323 	void		*driver_data;	/* data private to the driver */
324 	void		*platform_data;	/* Platform specific data, device
325 					   core doesn't touch it */
326 	void		*firmware_data; /* Firmware specific data (e.g. ACPI,
327 					   BIOS data),reserved for device core*/
328 	struct dev_pm_info	power;
329 
330 	u64		*dma_mask;	/* dma mask (if dma'able device) */
331 	u64		coherent_dma_mask;/* Like dma_mask, but for
332 					     alloc_coherent mappings as
333 					     not all hardware supports
334 					     64 bit addresses for consistent
335 					     allocations such descriptors. */
336 
337 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
338 
339 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
340 					     override */
341 
342 	void	(*release)(struct device * dev);
343 };
344 
345 static inline void *
346 dev_get_drvdata (struct device *dev)
347 {
348 	return dev->driver_data;
349 }
350 
351 static inline void
352 dev_set_drvdata (struct device *dev, void *data)
353 {
354 	dev->driver_data = data;
355 }
356 
357 static inline int device_is_registered(struct device *dev)
358 {
359 	return klist_node_attached(&dev->knode_bus);
360 }
361 
362 /*
363  * High level routines for use by the bus drivers
364  */
365 extern int device_register(struct device * dev);
366 extern void device_unregister(struct device * dev);
367 extern void device_initialize(struct device * dev);
368 extern int device_add(struct device * dev);
369 extern void device_del(struct device * dev);
370 extern int device_for_each_child(struct device *, void *,
371 		     int (*fn)(struct device *, void *));
372 
373 /*
374  * Manual binding of a device to driver. See drivers/base/bus.c
375  * for information on use.
376  */
377 extern void device_bind_driver(struct device * dev);
378 extern void device_release_driver(struct device * dev);
379 extern int  device_attach(struct device * dev);
380 extern void driver_attach(struct device_driver * drv);
381 extern void device_reprobe(struct device *dev);
382 
383 
384 /*
385  * Platform "fixup" functions - allow the platform to have their say
386  * about devices and actions that the general device layer doesn't
387  * know about.
388  */
389 /* Notify platform of device discovery */
390 extern int (*platform_notify)(struct device * dev);
391 
392 extern int (*platform_notify_remove)(struct device * dev);
393 
394 
395 /**
396  * get_device - atomically increment the reference count for the device.
397  *
398  */
399 extern struct device * get_device(struct device * dev);
400 extern void put_device(struct device * dev);
401 
402 
403 /* drivers/base/power/shutdown.c */
404 extern void device_shutdown(void);
405 
406 
407 /* drivers/base/firmware.c */
408 extern int firmware_register(struct subsystem *);
409 extern void firmware_unregister(struct subsystem *);
410 
411 /* debugging and troubleshooting/diagnostic helpers. */
412 #define dev_printk(level, dev, format, arg...)	\
413 	printk(level "%s %s: " format , (dev)->driver ? (dev)->driver->name : "" , (dev)->bus_id , ## arg)
414 
415 #ifdef DEBUG
416 #define dev_dbg(dev, format, arg...)		\
417 	dev_printk(KERN_DEBUG , dev , format , ## arg)
418 #else
419 #define dev_dbg(dev, format, arg...) do { (void)(dev); } while (0)
420 #endif
421 
422 #define dev_err(dev, format, arg...)		\
423 	dev_printk(KERN_ERR , dev , format , ## arg)
424 #define dev_info(dev, format, arg...)		\
425 	dev_printk(KERN_INFO , dev , format , ## arg)
426 #define dev_warn(dev, format, arg...)		\
427 	dev_printk(KERN_WARNING , dev , format , ## arg)
428 #define dev_notice(dev, format, arg...)		\
429 	dev_printk(KERN_NOTICE , dev , format , ## arg)
430 
431 /* Create alias, so I can be autoloaded. */
432 #define MODULE_ALIAS_CHARDEV(major,minor) \
433 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
434 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
435 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
436 #endif /* _DEVICE_H_ */
437