xref: /linux-6.15/include/linux/device.h (revision 4e57b681)
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		(*hotplug) (struct device *dev, char **envp,
51 				    int num_envp, char *buffer, int buffer_size);
52 	int		(*suspend)(struct device * dev, pm_message_t state);
53 	int		(*resume)(struct device * dev);
54 };
55 
56 extern int bus_register(struct bus_type * bus);
57 extern void bus_unregister(struct bus_type * bus);
58 
59 extern void bus_rescan_devices(struct bus_type * bus);
60 
61 extern struct bus_type * get_bus(struct bus_type * bus);
62 extern void put_bus(struct bus_type * bus);
63 
64 extern struct bus_type * find_bus(char * name);
65 
66 /* iterator helpers for buses */
67 
68 int bus_for_each_dev(struct bus_type * bus, struct device * start, void * data,
69 		     int (*fn)(struct device *, void *));
70 struct device * bus_find_device(struct bus_type *bus, struct device *start,
71 				void *data, int (*match)(struct device *, void *));
72 
73 int bus_for_each_drv(struct bus_type * bus, struct device_driver * start,
74 		     void * data, int (*fn)(struct device_driver *, void *));
75 
76 
77 /* driverfs interface for exporting bus attributes */
78 
79 struct bus_attribute {
80 	struct attribute	attr;
81 	ssize_t (*show)(struct bus_type *, char * buf);
82 	ssize_t (*store)(struct bus_type *, const char * buf, size_t count);
83 };
84 
85 #define BUS_ATTR(_name,_mode,_show,_store)	\
86 struct bus_attribute bus_attr_##_name = __ATTR(_name,_mode,_show,_store)
87 
88 extern int bus_create_file(struct bus_type *, struct bus_attribute *);
89 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
90 
91 struct device_driver {
92 	const char		* name;
93 	struct bus_type		* bus;
94 
95 	struct completion	unloaded;
96 	struct kobject		kobj;
97 	struct klist		klist_devices;
98 	struct klist_node	knode_bus;
99 
100 	struct module		* owner;
101 
102 	int	(*probe)	(struct device * dev);
103 	int	(*remove)	(struct device * dev);
104 	void	(*shutdown)	(struct device * dev);
105 	int	(*suspend)	(struct device * dev, pm_message_t state);
106 	int	(*resume)	(struct device * dev);
107 };
108 
109 
110 extern int driver_register(struct device_driver * drv);
111 extern void driver_unregister(struct device_driver * drv);
112 
113 extern struct device_driver * get_driver(struct device_driver * drv);
114 extern void put_driver(struct device_driver * drv);
115 extern struct device_driver *driver_find(const char *name, struct bus_type *bus);
116 
117 
118 /* driverfs interface for exporting driver attributes */
119 
120 struct driver_attribute {
121 	struct attribute	attr;
122 	ssize_t (*show)(struct device_driver *, char * buf);
123 	ssize_t (*store)(struct device_driver *, const char * buf, size_t count);
124 };
125 
126 #define DRIVER_ATTR(_name,_mode,_show,_store)	\
127 struct driver_attribute driver_attr_##_name = __ATTR(_name,_mode,_show,_store)
128 
129 extern int driver_create_file(struct device_driver *, struct driver_attribute *);
130 extern void driver_remove_file(struct device_driver *, struct driver_attribute *);
131 
132 extern int driver_for_each_device(struct device_driver * drv, struct device * start,
133 				  void * data, int (*fn)(struct device *, void *));
134 struct device * driver_find_device(struct device_driver *drv,
135 				   struct device *start, void *data,
136 				   int (*match)(struct device *, void *));
137 
138 
139 /*
140  * device classes
141  */
142 struct class {
143 	const char		* name;
144 	struct module		* owner;
145 
146 	struct subsystem	subsys;
147 	struct list_head	children;
148 	struct list_head	interfaces;
149 	struct semaphore	sem;	/* locks both the children and interfaces lists */
150 
151 	struct class_attribute		* class_attrs;
152 	struct class_device_attribute	* class_dev_attrs;
153 
154 	int	(*hotplug)(struct class_device *dev, char **envp,
155 			   int num_envp, char *buffer, int buffer_size);
156 
157 	void	(*release)(struct class_device *dev);
158 	void	(*class_release)(struct class *class);
159 };
160 
161 extern int class_register(struct class *);
162 extern void class_unregister(struct class *);
163 
164 extern struct class * class_get(struct class *);
165 extern void class_put(struct class *);
166 
167 
168 struct class_attribute {
169 	struct attribute	attr;
170 	ssize_t (*show)(struct class *, char * buf);
171 	ssize_t (*store)(struct class *, const char * buf, size_t count);
172 };
173 
174 #define CLASS_ATTR(_name,_mode,_show,_store)			\
175 struct class_attribute class_attr_##_name = __ATTR(_name,_mode,_show,_store)
176 
177 extern int class_create_file(struct class *, const struct class_attribute *);
178 extern void class_remove_file(struct class *, const struct class_attribute *);
179 
180 struct class_device_attribute {
181 	struct attribute	attr;
182 	ssize_t (*show)(struct class_device *, char * buf);
183 	ssize_t (*store)(struct class_device *, const char * buf, size_t count);
184 };
185 
186 #define CLASS_DEVICE_ATTR(_name,_mode,_show,_store)		\
187 struct class_device_attribute class_device_attr_##_name = 	\
188 	__ATTR(_name,_mode,_show,_store)
189 
190 extern int class_device_create_file(struct class_device *,
191 				    const struct class_device_attribute *);
192 
193 /**
194  * struct class_device - class devices
195  * @class: pointer to the parent class for this class device.  This is required.
196  * @devt: for internal use by the driver core only.
197  * @node: for internal use by the driver core only.
198  * @kobj: for internal use by the driver core only.
199  * @devt_attr: for internal use by the driver core only.
200  * @dev: if set, a symlink to the struct device is created in the sysfs
201  * directory for this struct class device.
202  * @class_data: pointer to whatever you want to store here for this struct
203  * class_device.  Use class_get_devdata() and class_set_devdata() to get and
204  * set this pointer.
205  * @parent: pointer to a struct class_device that is the parent of this struct
206  * class_device.  If NULL, this class_device will show up at the root of the
207  * struct class in sysfs (which is probably what you want to have happen.)
208  * @release: pointer to a release function for this struct class_device.  If
209  * set, this will be called instead of the class specific release function.
210  * Only use this if you want to override the default release function, like
211  * when you are nesting class_device structures.
212  * @hotplug: pointer to a hotplug function for this struct class_device.  If
213  * set, this will be called instead of the class specific hotplug function.
214  * Only use this if you want to override the default hotplug function, like
215  * when you are nesting class_device structures.
216  */
217 struct class_device {
218 	struct list_head	node;
219 
220 	struct kobject		kobj;
221 	struct class		* class;	/* required */
222 	dev_t			devt;		/* dev_t, creates the sysfs "dev" */
223 	struct class_device_attribute *devt_attr;
224 	struct class_device_attribute uevent_attr;
225 	struct device		* dev;		/* not necessary, but nice to have */
226 	void			* class_data;	/* class-specific data */
227 	struct class_device	*parent;	/* parent of this child device, if there is one */
228 
229 	void	(*release)(struct class_device *dev);
230 	int	(*hotplug)(struct class_device *dev, char **envp,
231 			   int num_envp, char *buffer, int buffer_size);
232 	char	class_id[BUS_ID_SIZE];	/* unique to this class */
233 };
234 
235 static inline void *
236 class_get_devdata (struct class_device *dev)
237 {
238 	return dev->class_data;
239 }
240 
241 static inline void
242 class_set_devdata (struct class_device *dev, void *data)
243 {
244 	dev->class_data = data;
245 }
246 
247 
248 extern int class_device_register(struct class_device *);
249 extern void class_device_unregister(struct class_device *);
250 extern void class_device_initialize(struct class_device *);
251 extern int class_device_add(struct class_device *);
252 extern void class_device_del(struct class_device *);
253 
254 extern int class_device_rename(struct class_device *, char *);
255 
256 extern struct class_device * class_device_get(struct class_device *);
257 extern void class_device_put(struct class_device *);
258 
259 extern void class_device_remove_file(struct class_device *,
260 				     const struct class_device_attribute *);
261 extern int class_device_create_bin_file(struct class_device *,
262 					struct bin_attribute *);
263 extern void class_device_remove_bin_file(struct class_device *,
264 					 struct bin_attribute *);
265 
266 struct class_interface {
267 	struct list_head	node;
268 	struct class		*class;
269 
270 	int (*add)	(struct class_device *, struct class_interface *);
271 	void (*remove)	(struct class_device *, struct class_interface *);
272 };
273 
274 extern int class_interface_register(struct class_interface *);
275 extern void class_interface_unregister(struct class_interface *);
276 
277 extern struct class *class_create(struct module *owner, char *name);
278 extern void class_destroy(struct class *cls);
279 extern struct class_device *class_device_create(struct class *cls,
280 						struct class_device *parent,
281 						dev_t devt,
282 						struct device *device,
283 						char *fmt, ...)
284 					__attribute__((format(printf,5,6)));
285 extern void class_device_destroy(struct class *cls, dev_t devt);
286 
287 
288 /* interface for exporting device attributes */
289 struct device_attribute {
290 	struct attribute	attr;
291 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
292 			char *buf);
293 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
294 			 const char *buf, size_t count);
295 };
296 
297 #define DEVICE_ATTR(_name,_mode,_show,_store) \
298 struct device_attribute dev_attr_##_name = __ATTR(_name,_mode,_show,_store)
299 
300 extern int device_create_file(struct device *device, struct device_attribute * entry);
301 extern void device_remove_file(struct device * dev, struct device_attribute * attr);
302 struct device {
303 	struct klist		klist_children;
304 	struct klist_node	knode_parent;		/* node in sibling list */
305 	struct klist_node	knode_driver;
306 	struct klist_node	knode_bus;
307 	struct device 	* parent;
308 
309 	struct kobject kobj;
310 	char	bus_id[BUS_ID_SIZE];	/* position on parent bus */
311 	struct device_attribute uevent_attr;
312 
313 	struct semaphore	sem;	/* semaphore to synchronize calls to
314 					 * its driver.
315 					 */
316 
317 	struct bus_type	* bus;		/* type of bus device is on */
318 	struct device_driver *driver;	/* which driver has allocated this
319 					   device */
320 	void		*driver_data;	/* data private to the driver */
321 	void		*platform_data;	/* Platform specific data, device
322 					   core doesn't touch it */
323 	void		*firmware_data; /* Firmware specific data (e.g. ACPI,
324 					   BIOS data),reserved for device core*/
325 	struct dev_pm_info	power;
326 
327 	u64		*dma_mask;	/* dma mask (if dma'able device) */
328 	u64		coherent_dma_mask;/* Like dma_mask, but for
329 					     alloc_coherent mappings as
330 					     not all hardware supports
331 					     64 bit addresses for consistent
332 					     allocations such descriptors. */
333 
334 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
335 
336 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
337 					     override */
338 
339 	void	(*release)(struct device * dev);
340 };
341 
342 static inline void *
343 dev_get_drvdata (struct device *dev)
344 {
345 	return dev->driver_data;
346 }
347 
348 static inline void
349 dev_set_drvdata (struct device *dev, void *data)
350 {
351 	dev->driver_data = data;
352 }
353 
354 static inline int device_is_registered(struct device *dev)
355 {
356 	return klist_node_attached(&dev->knode_bus);
357 }
358 
359 /*
360  * High level routines for use by the bus drivers
361  */
362 extern int device_register(struct device * dev);
363 extern void device_unregister(struct device * dev);
364 extern void device_initialize(struct device * dev);
365 extern int device_add(struct device * dev);
366 extern void device_del(struct device * dev);
367 extern int device_for_each_child(struct device *, void *,
368 		     int (*fn)(struct device *, void *));
369 
370 /*
371  * Manual binding of a device to driver. See drivers/base/bus.c
372  * for information on use.
373  */
374 extern void device_bind_driver(struct device * dev);
375 extern void device_release_driver(struct device * dev);
376 extern int  device_attach(struct device * dev);
377 extern void driver_attach(struct device_driver * drv);
378 
379 
380 /*
381  * Platform "fixup" functions - allow the platform to have their say
382  * about devices and actions that the general device layer doesn't
383  * know about.
384  */
385 /* Notify platform of device discovery */
386 extern int (*platform_notify)(struct device * dev);
387 
388 extern int (*platform_notify_remove)(struct device * dev);
389 
390 
391 /**
392  * get_device - atomically increment the reference count for the device.
393  *
394  */
395 extern struct device * get_device(struct device * dev);
396 extern void put_device(struct device * dev);
397 
398 
399 /* drivers/base/platform.c */
400 
401 struct platform_device {
402 	const char	* name;
403 	u32		id;
404 	struct device	dev;
405 	u32		num_resources;
406 	struct resource	* resource;
407 };
408 
409 #define to_platform_device(x) container_of((x), struct platform_device, dev)
410 
411 extern int platform_device_register(struct platform_device *);
412 extern void platform_device_unregister(struct platform_device *);
413 
414 extern struct bus_type platform_bus_type;
415 extern struct device platform_bus;
416 
417 extern struct resource *platform_get_resource(struct platform_device *, unsigned int, unsigned int);
418 extern int platform_get_irq(struct platform_device *, unsigned int);
419 extern struct resource *platform_get_resource_byname(struct platform_device *, unsigned int, char *);
420 extern int platform_get_irq_byname(struct platform_device *, char *);
421 extern int platform_add_devices(struct platform_device **, int);
422 
423 extern struct platform_device *platform_device_register_simple(char *, unsigned int, struct resource *, unsigned int);
424 
425 /* drivers/base/power.c */
426 extern void device_shutdown(void);
427 
428 
429 /* drivers/base/firmware.c */
430 extern int firmware_register(struct subsystem *);
431 extern void firmware_unregister(struct subsystem *);
432 
433 /* debugging and troubleshooting/diagnostic helpers. */
434 #define dev_printk(level, dev, format, arg...)	\
435 	printk(level "%s %s: " format , (dev)->driver ? (dev)->driver->name : "" , (dev)->bus_id , ## arg)
436 
437 #ifdef DEBUG
438 #define dev_dbg(dev, format, arg...)		\
439 	dev_printk(KERN_DEBUG , dev , format , ## arg)
440 #else
441 #define dev_dbg(dev, format, arg...) do { (void)(dev); } while (0)
442 #endif
443 
444 #define dev_err(dev, format, arg...)		\
445 	dev_printk(KERN_ERR , dev , format , ## arg)
446 #define dev_info(dev, format, arg...)		\
447 	dev_printk(KERN_INFO , dev , format , ## arg)
448 #define dev_warn(dev, format, arg...)		\
449 	dev_printk(KERN_WARNING , dev , format , ## arg)
450 
451 /* Create alias, so I can be autoloaded. */
452 #define MODULE_ALIAS_CHARDEV(major,minor) \
453 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
454 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
455 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
456 #endif /* _DEVICE_H_ */
457