• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * device.h - generic, centralized driver model
3  *
4  * Copyright (c) 2001-2003 Patrick Mochel <mochel@osdl.org>
5  * Copyright (c) 2004-2009 Greg Kroah-Hartman <gregkh@suse.de>
6  * Copyright (c) 2008-2009 Novell Inc.
7  *
8  * This file is released under the GPLv2
9  *
10  * See Documentation/driver-model/ for more information.
11  */
12 
13 #ifndef _DEVICE_H_
14 #define _DEVICE_H_
15 
16 #include <linux/ioport.h>
17 #include <linux/kobject.h>
18 #include <linux/klist.h>
19 #include <linux/list.h>
20 #include <linux/lockdep.h>
21 #include <linux/compiler.h>
22 #include <linux/types.h>
23 #include <linux/mutex.h>
24 #include <linux/pinctrl/devinfo.h>
25 #include <linux/pm.h>
26 #include <linux/atomic.h>
27 #include <linux/ratelimit.h>
28 #include <linux/uidgid.h>
29 #include <linux/gfp.h>
30 #include <asm/device.h>
31 
32 struct device;
33 struct device_private;
34 struct device_driver;
35 struct driver_private;
36 struct module;
37 struct class;
38 struct subsys_private;
39 struct bus_type;
40 struct device_node;
41 struct fwnode_handle;
42 struct iommu_ops;
43 struct iommu_group;
44 struct iommu_fwspec;
45 
46 struct bus_attribute {
47 	struct attribute	attr;
48 	ssize_t (*show)(struct bus_type *bus, char *buf);
49 	ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
50 };
51 
52 #define BUS_ATTR(_name, _mode, _show, _store)	\
53 	struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)
54 #define BUS_ATTR_RW(_name) \
55 	struct bus_attribute bus_attr_##_name = __ATTR_RW(_name)
56 #define BUS_ATTR_RO(_name) \
57 	struct bus_attribute bus_attr_##_name = __ATTR_RO(_name)
58 
59 extern int __must_check bus_create_file(struct bus_type *,
60 					struct bus_attribute *);
61 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
62 
63 /**
64  * struct bus_type - The bus type of the device
65  *
66  * @name:	The name of the bus.
67  * @dev_name:	Used for subsystems to enumerate devices like ("foo%u", dev->id).
68  * @dev_root:	Default device to use as the parent.
69  * @bus_groups:	Default attributes of the bus.
70  * @dev_groups:	Default attributes of the devices on the bus.
71  * @drv_groups: Default attributes of the device drivers on the bus.
72  * @match:	Called, perhaps multiple times, whenever a new device or driver
73  *		is added for this bus. It should return a positive value if the
74  *		given device can be handled by the given driver and zero
75  *		otherwise. It may also return error code if determining that
76  *		the driver supports the device is not possible. In case of
77  *		-EPROBE_DEFER it will queue the device for deferred probing.
78  * @uevent:	Called when a device is added, removed, or a few other things
79  *		that generate uevents to add the environment variables.
80  * @probe:	Called when a new device or driver add to this bus, and callback
81  *		the specific driver's probe to initial the matched device.
82  * @remove:	Called when a device removed from this bus.
83  * @shutdown:	Called at shut-down time to quiesce the device.
84  *
85  * @online:	Called to put the device back online (after offlining it).
86  * @offline:	Called to put the device offline for hot-removal. May fail.
87  *
88  * @suspend:	Called when a device on this bus wants to go to sleep mode.
89  * @resume:	Called to bring a device on this bus out of sleep mode.
90  * @num_vf:	Called to find out how many virtual functions a device on this
91  *		bus supports.
92  * @pm:		Power management operations of this bus, callback the specific
93  *		device driver's pm-ops.
94  * @iommu_ops:  IOMMU specific operations for this bus, used to attach IOMMU
95  *              driver implementations to a bus and allow the driver to do
96  *              bus-specific setup
97  * @p:		The private data of the driver core, only the driver core can
98  *		touch this.
99  * @lock_key:	Lock class key for use by the lock validator
100  *
101  * A bus is a channel between the processor and one or more devices. For the
102  * purposes of the device model, all devices are connected via a bus, even if
103  * it is an internal, virtual, "platform" bus. Buses can plug into each other.
104  * A USB controller is usually a PCI device, for example. The device model
105  * represents the actual connections between buses and the devices they control.
106  * A bus is represented by the bus_type structure. It contains the name, the
107  * default attributes, the bus' methods, PM operations, and the driver core's
108  * private data.
109  */
110 struct bus_type {
111 	const char		*name;
112 	const char		*dev_name;
113 	struct device		*dev_root;
114 	const struct attribute_group **bus_groups;
115 	const struct attribute_group **dev_groups;
116 	const struct attribute_group **drv_groups;
117 
118 	int (*match)(struct device *dev, struct device_driver *drv);
119 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
120 	int (*probe)(struct device *dev);
121 	int (*remove)(struct device *dev);
122 	void (*shutdown)(struct device *dev);
123 
124 	int (*online)(struct device *dev);
125 	int (*offline)(struct device *dev);
126 
127 	int (*suspend)(struct device *dev, pm_message_t state);
128 	int (*resume)(struct device *dev);
129 
130 	int (*num_vf)(struct device *dev);
131 
132 	const struct dev_pm_ops *pm;
133 
134 	const struct iommu_ops *iommu_ops;
135 
136 	struct subsys_private *p;
137 	struct lock_class_key lock_key;
138 };
139 
140 extern int __must_check bus_register(struct bus_type *bus);
141 
142 extern void bus_unregister(struct bus_type *bus);
143 
144 extern int __must_check bus_rescan_devices(struct bus_type *bus);
145 
146 /* iterator helpers for buses */
147 struct subsys_dev_iter {
148 	struct klist_iter		ki;
149 	const struct device_type	*type;
150 };
151 void subsys_dev_iter_init(struct subsys_dev_iter *iter,
152 			 struct bus_type *subsys,
153 			 struct device *start,
154 			 const struct device_type *type);
155 struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter);
156 void subsys_dev_iter_exit(struct subsys_dev_iter *iter);
157 
158 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
159 		     int (*fn)(struct device *dev, void *data));
160 struct device *bus_find_device(struct bus_type *bus, struct device *start,
161 			       void *data,
162 			       int (*match)(struct device *dev, void *data));
163 struct device *bus_find_device_by_name(struct bus_type *bus,
164 				       struct device *start,
165 				       const char *name);
166 struct device *subsys_find_device_by_id(struct bus_type *bus, unsigned int id,
167 					struct device *hint);
168 int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
169 		     void *data, int (*fn)(struct device_driver *, void *));
170 void bus_sort_breadthfirst(struct bus_type *bus,
171 			   int (*compare)(const struct device *a,
172 					  const struct device *b));
173 /*
174  * Bus notifiers: Get notified of addition/removal of devices
175  * and binding/unbinding of drivers to devices.
176  * In the long run, it should be a replacement for the platform
177  * notify hooks.
178  */
179 struct notifier_block;
180 
181 extern int bus_register_notifier(struct bus_type *bus,
182 				 struct notifier_block *nb);
183 extern int bus_unregister_notifier(struct bus_type *bus,
184 				   struct notifier_block *nb);
185 
186 /* All 4 notifers below get called with the target struct device *
187  * as an argument. Note that those functions are likely to be called
188  * with the device lock held in the core, so be careful.
189  */
190 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
191 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device to be removed */
192 #define BUS_NOTIFY_REMOVED_DEVICE	0x00000003 /* device removed */
193 #define BUS_NOTIFY_BIND_DRIVER		0x00000004 /* driver about to be
194 						      bound */
195 #define BUS_NOTIFY_BOUND_DRIVER		0x00000005 /* driver bound to device */
196 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000006 /* driver about to be
197 						      unbound */
198 #define BUS_NOTIFY_UNBOUND_DRIVER	0x00000007 /* driver is unbound
199 						      from the device */
200 #define BUS_NOTIFY_DRIVER_NOT_BOUND	0x00000008 /* driver fails to be bound */
201 
202 extern struct kset *bus_get_kset(struct bus_type *bus);
203 extern struct klist *bus_get_device_klist(struct bus_type *bus);
204 
205 /**
206  * enum probe_type - device driver probe type to try
207  *	Device drivers may opt in for special handling of their
208  *	respective probe routines. This tells the core what to
209  *	expect and prefer.
210  *
211  * @PROBE_DEFAULT_STRATEGY: Used by drivers that work equally well
212  *	whether probed synchronously or asynchronously.
213  * @PROBE_PREFER_ASYNCHRONOUS: Drivers for "slow" devices which
214  *	probing order is not essential for booting the system may
215  *	opt into executing their probes asynchronously.
216  * @PROBE_FORCE_SYNCHRONOUS: Use this to annotate drivers that need
217  *	their probe routines to run synchronously with driver and
218  *	device registration (with the exception of -EPROBE_DEFER
219  *	handling - re-probing always ends up being done asynchronously).
220  *
221  * Note that the end goal is to switch the kernel to use asynchronous
222  * probing by default, so annotating drivers with
223  * %PROBE_PREFER_ASYNCHRONOUS is a temporary measure that allows us
224  * to speed up boot process while we are validating the rest of the
225  * drivers.
226  */
227 enum probe_type {
228 	PROBE_DEFAULT_STRATEGY,
229 	PROBE_PREFER_ASYNCHRONOUS,
230 	PROBE_FORCE_SYNCHRONOUS,
231 };
232 
233 /**
234  * struct device_driver - The basic device driver structure
235  * @name:	Name of the device driver.
236  * @bus:	The bus which the device of this driver belongs to.
237  * @owner:	The module owner.
238  * @mod_name:	Used for built-in modules.
239  * @suppress_bind_attrs: Disables bind/unbind via sysfs.
240  * @probe_type:	Type of the probe (synchronous or asynchronous) to use.
241  * @of_match_table: The open firmware table.
242  * @acpi_match_table: The ACPI match table.
243  * @probe:	Called to query the existence of a specific device,
244  *		whether this driver can work with it, and bind the driver
245  *		to a specific device.
246  * @remove:	Called when the device is removed from the system to
247  *		unbind a device from this driver.
248  * @shutdown:	Called at shut-down time to quiesce the device.
249  * @suspend:	Called to put the device to sleep mode. Usually to a
250  *		low power state.
251  * @resume:	Called to bring a device from sleep mode.
252  * @groups:	Default attributes that get created by the driver core
253  *		automatically.
254  * @pm:		Power management operations of the device which matched
255  *		this driver.
256  * @p:		Driver core's private data, no one other than the driver
257  *		core can touch this.
258  *
259  * The device driver-model tracks all of the drivers known to the system.
260  * The main reason for this tracking is to enable the driver core to match
261  * up drivers with new devices. Once drivers are known objects within the
262  * system, however, a number of other things become possible. Device drivers
263  * can export information and configuration variables that are independent
264  * of any specific device.
265  */
266 struct device_driver {
267 	const char		*name;
268 	struct bus_type		*bus;
269 
270 	struct module		*owner;
271 	const char		*mod_name;	/* used for built-in modules */
272 
273 	bool suppress_bind_attrs;	/* disables bind/unbind via sysfs */
274 	enum probe_type probe_type;
275 
276 	const struct of_device_id	*of_match_table;
277 	const struct acpi_device_id	*acpi_match_table;
278 
279 	int (*probe) (struct device *dev);
280 	int (*remove) (struct device *dev);
281 	void (*shutdown) (struct device *dev);
282 	int (*suspend) (struct device *dev, pm_message_t state);
283 	int (*resume) (struct device *dev);
284 	const struct attribute_group **groups;
285 
286 	const struct dev_pm_ops *pm;
287 
288 	struct driver_private *p;
289 };
290 
291 
292 extern int __must_check driver_register(struct device_driver *drv);
293 extern void driver_unregister(struct device_driver *drv);
294 
295 extern struct device_driver *driver_find(const char *name,
296 					 struct bus_type *bus);
297 extern int driver_probe_done(void);
298 extern void wait_for_device_probe(void);
299 
300 
301 /* sysfs interface for exporting driver attributes */
302 
303 struct driver_attribute {
304 	struct attribute attr;
305 	ssize_t (*show)(struct device_driver *driver, char *buf);
306 	ssize_t (*store)(struct device_driver *driver, const char *buf,
307 			 size_t count);
308 };
309 
310 #define DRIVER_ATTR_RW(_name) \
311 	struct driver_attribute driver_attr_##_name = __ATTR_RW(_name)
312 #define DRIVER_ATTR_RO(_name) \
313 	struct driver_attribute driver_attr_##_name = __ATTR_RO(_name)
314 #define DRIVER_ATTR_WO(_name) \
315 	struct driver_attribute driver_attr_##_name = __ATTR_WO(_name)
316 
317 extern int __must_check driver_create_file(struct device_driver *driver,
318 					const struct driver_attribute *attr);
319 extern void driver_remove_file(struct device_driver *driver,
320 			       const struct driver_attribute *attr);
321 
322 extern int __must_check driver_for_each_device(struct device_driver *drv,
323 					       struct device *start,
324 					       void *data,
325 					       int (*fn)(struct device *dev,
326 							 void *));
327 struct device *driver_find_device(struct device_driver *drv,
328 				  struct device *start, void *data,
329 				  int (*match)(struct device *dev, void *data));
330 
331 /**
332  * struct subsys_interface - interfaces to device functions
333  * @name:       name of the device function
334  * @subsys:     subsytem of the devices to attach to
335  * @node:       the list of functions registered at the subsystem
336  * @add_dev:    device hookup to device function handler
337  * @remove_dev: device hookup to device function handler
338  *
339  * Simple interfaces attached to a subsystem. Multiple interfaces can
340  * attach to a subsystem and its devices. Unlike drivers, they do not
341  * exclusively claim or control devices. Interfaces usually represent
342  * a specific functionality of a subsystem/class of devices.
343  */
344 struct subsys_interface {
345 	const char *name;
346 	struct bus_type *subsys;
347 	struct list_head node;
348 	int (*add_dev)(struct device *dev, struct subsys_interface *sif);
349 	void (*remove_dev)(struct device *dev, struct subsys_interface *sif);
350 };
351 
352 int subsys_interface_register(struct subsys_interface *sif);
353 void subsys_interface_unregister(struct subsys_interface *sif);
354 
355 int subsys_system_register(struct bus_type *subsys,
356 			   const struct attribute_group **groups);
357 int subsys_virtual_register(struct bus_type *subsys,
358 			    const struct attribute_group **groups);
359 
360 /**
361  * struct class - device classes
362  * @name:	Name of the class.
363  * @owner:	The module owner.
364  * @class_groups: Default attributes of this class.
365  * @dev_groups:	Default attributes of the devices that belong to the class.
366  * @dev_kobj:	The kobject that represents this class and links it into the hierarchy.
367  * @dev_uevent:	Called when a device is added, removed from this class, or a
368  *		few other things that generate uevents to add the environment
369  *		variables.
370  * @devnode:	Callback to provide the devtmpfs.
371  * @class_release: Called to release this class.
372  * @dev_release: Called to release the device.
373  * @suspend:	Used to put the device to sleep mode, usually to a low power
374  *		state.
375  * @resume:	Used to bring the device from the sleep mode.
376  * @shutdown_pre: Called at shut-down time before driver shutdown.
377  * @ns_type:	Callbacks so sysfs can detemine namespaces.
378  * @namespace:	Namespace of the device belongs to this class.
379  * @pm:		The default device power management operations of this class.
380  * @p:		The private data of the driver core, no one other than the
381  *		driver core can touch this.
382  *
383  * A class is a higher-level view of a device that abstracts out low-level
384  * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
385  * at the class level, they are all simply disks. Classes allow user space
386  * to work with devices based on what they do, rather than how they are
387  * connected or how they work.
388  */
389 struct class {
390 	const char		*name;
391 	struct module		*owner;
392 
393 	const struct attribute_group	**class_groups;
394 	const struct attribute_group	**dev_groups;
395 	struct kobject			*dev_kobj;
396 
397 	int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
398 	char *(*devnode)(struct device *dev, umode_t *mode);
399 
400 	void (*class_release)(struct class *class);
401 	void (*dev_release)(struct device *dev);
402 
403 	int (*suspend)(struct device *dev, pm_message_t state);
404 	int (*resume)(struct device *dev);
405 	int (*shutdown_pre)(struct device *dev);
406 
407 	const struct kobj_ns_type_operations *ns_type;
408 	const void *(*namespace)(struct device *dev);
409 
410 	const struct dev_pm_ops *pm;
411 
412 	struct subsys_private *p;
413 };
414 
415 struct class_dev_iter {
416 	struct klist_iter		ki;
417 	const struct device_type	*type;
418 };
419 
420 extern struct kobject *sysfs_dev_block_kobj;
421 extern struct kobject *sysfs_dev_char_kobj;
422 extern int __must_check __class_register(struct class *class,
423 					 struct lock_class_key *key);
424 extern void class_unregister(struct class *class);
425 
426 /* This is a #define to keep the compiler from merging different
427  * instances of the __key variable */
428 #define class_register(class)			\
429 ({						\
430 	static struct lock_class_key __key;	\
431 	__class_register(class, &__key);	\
432 })
433 
434 struct class_compat;
435 struct class_compat *class_compat_register(const char *name);
436 void class_compat_unregister(struct class_compat *cls);
437 int class_compat_create_link(struct class_compat *cls, struct device *dev,
438 			     struct device *device_link);
439 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
440 			      struct device *device_link);
441 
442 extern void class_dev_iter_init(struct class_dev_iter *iter,
443 				struct class *class,
444 				struct device *start,
445 				const struct device_type *type);
446 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
447 extern void class_dev_iter_exit(struct class_dev_iter *iter);
448 
449 extern int class_for_each_device(struct class *class, struct device *start,
450 				 void *data,
451 				 int (*fn)(struct device *dev, void *data));
452 extern struct device *class_find_device(struct class *class,
453 					struct device *start, const void *data,
454 					int (*match)(struct device *, const void *));
455 
456 struct class_attribute {
457 	struct attribute attr;
458 	ssize_t (*show)(struct class *class, struct class_attribute *attr,
459 			char *buf);
460 	ssize_t (*store)(struct class *class, struct class_attribute *attr,
461 			const char *buf, size_t count);
462 };
463 
464 #define CLASS_ATTR_RW(_name) \
465 	struct class_attribute class_attr_##_name = __ATTR_RW(_name)
466 #define CLASS_ATTR_RO(_name) \
467 	struct class_attribute class_attr_##_name = __ATTR_RO(_name)
468 #define CLASS_ATTR_WO(_name) \
469 	struct class_attribute class_attr_##_name = __ATTR_WO(_name)
470 
471 extern int __must_check class_create_file_ns(struct class *class,
472 					     const struct class_attribute *attr,
473 					     const void *ns);
474 extern void class_remove_file_ns(struct class *class,
475 				 const struct class_attribute *attr,
476 				 const void *ns);
477 
class_create_file(struct class * class,const struct class_attribute * attr)478 static inline int __must_check class_create_file(struct class *class,
479 					const struct class_attribute *attr)
480 {
481 	return class_create_file_ns(class, attr, NULL);
482 }
483 
class_remove_file(struct class * class,const struct class_attribute * attr)484 static inline void class_remove_file(struct class *class,
485 				     const struct class_attribute *attr)
486 {
487 	return class_remove_file_ns(class, attr, NULL);
488 }
489 
490 /* Simple class attribute that is just a static string */
491 struct class_attribute_string {
492 	struct class_attribute attr;
493 	char *str;
494 };
495 
496 /* Currently read-only only */
497 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
498 	{ __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
499 #define CLASS_ATTR_STRING(_name, _mode, _str) \
500 	struct class_attribute_string class_attr_##_name = \
501 		_CLASS_ATTR_STRING(_name, _mode, _str)
502 
503 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
504                         char *buf);
505 
506 struct class_interface {
507 	struct list_head	node;
508 	struct class		*class;
509 
510 	int (*add_dev)		(struct device *, struct class_interface *);
511 	void (*remove_dev)	(struct device *, struct class_interface *);
512 };
513 
514 extern int __must_check class_interface_register(struct class_interface *);
515 extern void class_interface_unregister(struct class_interface *);
516 
517 extern struct class * __must_check __class_create(struct module *owner,
518 						  const char *name,
519 						  struct lock_class_key *key);
520 extern void class_destroy(struct class *cls);
521 
522 /* This is a #define to keep the compiler from merging different
523  * instances of the __key variable */
524 #define class_create(owner, name)		\
525 ({						\
526 	static struct lock_class_key __key;	\
527 	__class_create(owner, name, &__key);	\
528 })
529 
530 /*
531  * The type of device, "struct device" is embedded in. A class
532  * or bus can contain devices of different types
533  * like "partitions" and "disks", "mouse" and "event".
534  * This identifies the device type and carries type-specific
535  * information, equivalent to the kobj_type of a kobject.
536  * If "name" is specified, the uevent will contain it in
537  * the DEVTYPE variable.
538  */
539 struct device_type {
540 	const char *name;
541 	const struct attribute_group **groups;
542 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
543 	char *(*devnode)(struct device *dev, umode_t *mode,
544 			 kuid_t *uid, kgid_t *gid);
545 	void (*release)(struct device *dev);
546 
547 	const struct dev_pm_ops *pm;
548 };
549 
550 /* interface for exporting device attributes */
551 struct device_attribute {
552 	struct attribute	attr;
553 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
554 			char *buf);
555 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
556 			 const char *buf, size_t count);
557 };
558 
559 struct dev_ext_attribute {
560 	struct device_attribute attr;
561 	void *var;
562 };
563 
564 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
565 			  char *buf);
566 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
567 			   const char *buf, size_t count);
568 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
569 			char *buf);
570 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
571 			 const char *buf, size_t count);
572 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
573 			char *buf);
574 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
575 			 const char *buf, size_t count);
576 
577 #define DEVICE_ATTR(_name, _mode, _show, _store) \
578 	struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
579 #define DEVICE_ATTR_RW(_name) \
580 	struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
581 #define DEVICE_ATTR_RO(_name) \
582 	struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
583 #define DEVICE_ATTR_WO(_name) \
584 	struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
585 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
586 	struct dev_ext_attribute dev_attr_##_name = \
587 		{ __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
588 #define DEVICE_INT_ATTR(_name, _mode, _var) \
589 	struct dev_ext_attribute dev_attr_##_name = \
590 		{ __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
591 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
592 	struct dev_ext_attribute dev_attr_##_name = \
593 		{ __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
594 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
595 	struct device_attribute dev_attr_##_name =		\
596 		__ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
597 
598 extern int device_create_file(struct device *device,
599 			      const struct device_attribute *entry);
600 extern void device_remove_file(struct device *dev,
601 			       const struct device_attribute *attr);
602 extern bool device_remove_file_self(struct device *dev,
603 				    const struct device_attribute *attr);
604 extern int __must_check device_create_bin_file(struct device *dev,
605 					const struct bin_attribute *attr);
606 extern void device_remove_bin_file(struct device *dev,
607 				   const struct bin_attribute *attr);
608 
609 /* device resource management */
610 typedef void (*dr_release_t)(struct device *dev, void *res);
611 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
612 
613 #ifdef CONFIG_DEBUG_DEVRES
614 extern void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
615 				 int nid, const char *name) __malloc;
616 #define devres_alloc(release, size, gfp) \
617 	__devres_alloc_node(release, size, gfp, NUMA_NO_NODE, #release)
618 #define devres_alloc_node(release, size, gfp, nid) \
619 	__devres_alloc_node(release, size, gfp, nid, #release)
620 #else
621 extern void *devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
622 			       int nid) __malloc;
devres_alloc(dr_release_t release,size_t size,gfp_t gfp)623 static inline void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp)
624 {
625 	return devres_alloc_node(release, size, gfp, NUMA_NO_NODE);
626 }
627 #endif
628 
629 extern void devres_for_each_res(struct device *dev, dr_release_t release,
630 				dr_match_t match, void *match_data,
631 				void (*fn)(struct device *, void *, void *),
632 				void *data);
633 extern void devres_free(void *res);
634 extern void devres_add(struct device *dev, void *res);
635 extern void *devres_find(struct device *dev, dr_release_t release,
636 			 dr_match_t match, void *match_data);
637 extern void *devres_get(struct device *dev, void *new_res,
638 			dr_match_t match, void *match_data);
639 extern void *devres_remove(struct device *dev, dr_release_t release,
640 			   dr_match_t match, void *match_data);
641 extern int devres_destroy(struct device *dev, dr_release_t release,
642 			  dr_match_t match, void *match_data);
643 extern int devres_release(struct device *dev, dr_release_t release,
644 			  dr_match_t match, void *match_data);
645 
646 /* devres group */
647 extern void * __must_check devres_open_group(struct device *dev, void *id,
648 					     gfp_t gfp);
649 extern void devres_close_group(struct device *dev, void *id);
650 extern void devres_remove_group(struct device *dev, void *id);
651 extern int devres_release_group(struct device *dev, void *id);
652 
653 /* managed devm_k.alloc/kfree for device drivers */
654 extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __malloc;
655 extern __printf(3, 0)
656 char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt,
657 		      va_list ap) __malloc;
658 extern __printf(3, 4)
659 char *devm_kasprintf(struct device *dev, gfp_t gfp, const char *fmt, ...) __malloc;
devm_kzalloc(struct device * dev,size_t size,gfp_t gfp)660 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
661 {
662 	return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
663 }
devm_kmalloc_array(struct device * dev,size_t n,size_t size,gfp_t flags)664 static inline void *devm_kmalloc_array(struct device *dev,
665 				       size_t n, size_t size, gfp_t flags)
666 {
667 	if (size != 0 && n > SIZE_MAX / size)
668 		return NULL;
669 	return devm_kmalloc(dev, n * size, flags);
670 }
devm_kcalloc(struct device * dev,size_t n,size_t size,gfp_t flags)671 static inline void *devm_kcalloc(struct device *dev,
672 				 size_t n, size_t size, gfp_t flags)
673 {
674 	return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
675 }
676 extern void devm_kfree(struct device *dev, void *p);
677 extern char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
678 extern void *devm_kmemdup(struct device *dev, const void *src, size_t len,
679 			  gfp_t gfp);
680 
681 extern unsigned long devm_get_free_pages(struct device *dev,
682 					 gfp_t gfp_mask, unsigned int order);
683 extern void devm_free_pages(struct device *dev, unsigned long addr);
684 
685 void __iomem *devm_ioremap_resource(struct device *dev,
686 				    const struct resource *res);
687 
688 /* allows to add/remove a custom action to devres stack */
689 int devm_add_action(struct device *dev, void (*action)(void *), void *data);
690 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
691 
devm_add_action_or_reset(struct device * dev,void (* action)(void *),void * data)692 static inline int devm_add_action_or_reset(struct device *dev,
693 					   void (*action)(void *), void *data)
694 {
695 	int ret;
696 
697 	ret = devm_add_action(dev, action, data);
698 	if (ret)
699 		action(data);
700 
701 	return ret;
702 }
703 
704 /**
705  * devm_alloc_percpu - Resource-managed alloc_percpu
706  * @dev: Device to allocate per-cpu memory for
707  * @type: Type to allocate per-cpu memory for
708  *
709  * Managed alloc_percpu. Per-cpu memory allocated with this function is
710  * automatically freed on driver detach.
711  *
712  * RETURNS:
713  * Pointer to allocated memory on success, NULL on failure.
714  */
715 #define devm_alloc_percpu(dev, type)      \
716 	((typeof(type) __percpu *)__devm_alloc_percpu((dev), sizeof(type), \
717 						      __alignof__(type)))
718 
719 void __percpu *__devm_alloc_percpu(struct device *dev, size_t size,
720 				   size_t align);
721 void devm_free_percpu(struct device *dev, void __percpu *pdata);
722 
723 struct device_dma_parameters {
724 	/*
725 	 * a low level driver may set these to teach IOMMU code about
726 	 * sg limitations.
727 	 */
728 	unsigned int max_segment_size;
729 	unsigned long segment_boundary_mask;
730 };
731 
732 /**
733  * enum device_link_state - Device link states.
734  * @DL_STATE_NONE: The presence of the drivers is not being tracked.
735  * @DL_STATE_DORMANT: None of the supplier/consumer drivers is present.
736  * @DL_STATE_AVAILABLE: The supplier driver is present, but the consumer is not.
737  * @DL_STATE_CONSUMER_PROBE: The consumer is probing (supplier driver present).
738  * @DL_STATE_ACTIVE: Both the supplier and consumer drivers are present.
739  * @DL_STATE_SUPPLIER_UNBIND: The supplier driver is unbinding.
740  */
741 enum device_link_state {
742 	DL_STATE_NONE = -1,
743 	DL_STATE_DORMANT = 0,
744 	DL_STATE_AVAILABLE,
745 	DL_STATE_CONSUMER_PROBE,
746 	DL_STATE_ACTIVE,
747 	DL_STATE_SUPPLIER_UNBIND,
748 };
749 
750 /*
751  * Device link flags.
752  *
753  * STATELESS: The core won't track the presence of supplier/consumer drivers.
754  * AUTOREMOVE: Remove this link automatically on consumer driver unbind.
755  * PM_RUNTIME: If set, the runtime PM framework will use this link.
756  * RPM_ACTIVE: Run pm_runtime_get_sync() on the supplier during link creation.
757  */
758 #define DL_FLAG_STATELESS	BIT(0)
759 #define DL_FLAG_AUTOREMOVE	BIT(1)
760 #define DL_FLAG_PM_RUNTIME	BIT(2)
761 #define DL_FLAG_RPM_ACTIVE	BIT(3)
762 
763 /**
764  * struct device_link - Device link representation.
765  * @supplier: The device on the supplier end of the link.
766  * @s_node: Hook to the supplier device's list of links to consumers.
767  * @consumer: The device on the consumer end of the link.
768  * @c_node: Hook to the consumer device's list of links to suppliers.
769  * @status: The state of the link (with respect to the presence of drivers).
770  * @flags: Link flags.
771  * @rpm_active: Whether or not the consumer device is runtime-PM-active.
772  * @rcu_head: An RCU head to use for deferred execution of SRCU callbacks.
773  */
774 struct device_link {
775 	struct device *supplier;
776 	struct list_head s_node;
777 	struct device *consumer;
778 	struct list_head c_node;
779 	enum device_link_state status;
780 	u32 flags;
781 	bool rpm_active;
782 #ifdef CONFIG_SRCU
783 	struct rcu_head rcu_head;
784 #endif
785 };
786 
787 /**
788  * enum dl_dev_state - Device driver presence tracking information.
789  * @DL_DEV_NO_DRIVER: There is no driver attached to the device.
790  * @DL_DEV_PROBING: A driver is probing.
791  * @DL_DEV_DRIVER_BOUND: The driver has been bound to the device.
792  * @DL_DEV_UNBINDING: The driver is unbinding from the device.
793  */
794 enum dl_dev_state {
795 	DL_DEV_NO_DRIVER = 0,
796 	DL_DEV_PROBING,
797 	DL_DEV_DRIVER_BOUND,
798 	DL_DEV_UNBINDING,
799 };
800 
801 /**
802  * struct dev_links_info - Device data related to device links.
803  * @suppliers: List of links to supplier devices.
804  * @consumers: List of links to consumer devices.
805  * @status: Driver status information.
806  */
807 struct dev_links_info {
808 	struct list_head suppliers;
809 	struct list_head consumers;
810 	enum dl_dev_state status;
811 };
812 
813 /**
814  * struct device - The basic device structure
815  * @parent:	The device's "parent" device, the device to which it is attached.
816  * 		In most cases, a parent device is some sort of bus or host
817  * 		controller. If parent is NULL, the device, is a top-level device,
818  * 		which is not usually what you want.
819  * @p:		Holds the private data of the driver core portions of the device.
820  * 		See the comment of the struct device_private for detail.
821  * @kobj:	A top-level, abstract class from which other classes are derived.
822  * @init_name:	Initial name of the device.
823  * @type:	The type of device.
824  * 		This identifies the device type and carries type-specific
825  * 		information.
826  * @mutex:	Mutex to synchronize calls to its driver.
827  * @bus:	Type of bus device is on.
828  * @driver:	Which driver has allocated this
829  * @platform_data: Platform data specific to the device.
830  * 		Example: For devices on custom boards, as typical of embedded
831  * 		and SOC based hardware, Linux often uses platform_data to point
832  * 		to board-specific structures describing devices and how they
833  * 		are wired.  That can include what ports are available, chip
834  * 		variants, which GPIO pins act in what additional roles, and so
835  * 		on.  This shrinks the "Board Support Packages" (BSPs) and
836  * 		minimizes board-specific #ifdefs in drivers.
837  * @driver_data: Private pointer for driver specific info.
838  * @links:	Links to suppliers and consumers of this device.
839  * @power:	For device power management.
840  *		See Documentation/driver-api/pm/devices.rst for details.
841  * @pm_domain:	Provide callbacks that are executed during system suspend,
842  * 		hibernation, system resume and during runtime PM transitions
843  * 		along with subsystem-level and driver-level callbacks.
844  * @pins:	For device pin management.
845  *		See Documentation/driver-api/pinctl.rst for details.
846  * @msi_list:	Hosts MSI descriptors
847  * @msi_domain: The generic MSI domain this device is using.
848  * @numa_node:	NUMA node this device is close to.
849  * @dma_ops:    DMA mapping operations for this device.
850  * @dma_mask:	Dma mask (if dma'ble device).
851  * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
852  * 		hardware supports 64-bit addresses for consistent allocations
853  * 		such descriptors.
854  * @dma_pfn_offset: offset of DMA memory range relatively of RAM
855  * @dma_parms:	A low level driver may set these to teach IOMMU code about
856  * 		segment limitations.
857  * @dma_pools:	Dma pools (if dma'ble device).
858  * @dma_mem:	Internal for coherent mem override.
859  * @cma_area:	Contiguous memory area for dma allocations
860  * @archdata:	For arch-specific additions.
861  * @of_node:	Associated device tree node.
862  * @fwnode:	Associated device node supplied by platform firmware.
863  * @devt:	For creating the sysfs "dev".
864  * @id:		device instance
865  * @devres_lock: Spinlock to protect the resource of the device.
866  * @devres_head: The resources list of the device.
867  * @knode_class: The node used to add the device to the class list.
868  * @class:	The class of the device.
869  * @groups:	Optional attribute groups.
870  * @release:	Callback to free the device after all references have
871  * 		gone away. This should be set by the allocator of the
872  * 		device (i.e. the bus driver that discovered the device).
873  * @iommu_group: IOMMU group the device belongs to.
874  * @iommu_fwspec: IOMMU-specific properties supplied by firmware.
875  *
876  * @offline_disabled: If set, the device is permanently online.
877  * @offline:	Set after successful invocation of bus type's .offline().
878  * @of_node_reused: Set if the device-tree node is shared with an ancestor
879  *              device.
880  *
881  * At the lowest level, every device in a Linux system is represented by an
882  * instance of struct device. The device structure contains the information
883  * that the device model core needs to model the system. Most subsystems,
884  * however, track additional information about the devices they host. As a
885  * result, it is rare for devices to be represented by bare device structures;
886  * instead, that structure, like kobject structures, is usually embedded within
887  * a higher-level representation of the device.
888  */
889 struct device {
890 	struct device		*parent;
891 
892 	struct device_private	*p;
893 
894 	struct kobject kobj;
895 	const char		*init_name; /* initial name of the device */
896 	const struct device_type *type;
897 
898 	struct mutex		mutex;	/* mutex to synchronize calls to
899 					 * its driver.
900 					 */
901 
902 	struct bus_type	*bus;		/* type of bus device is on */
903 	struct device_driver *driver;	/* which driver has allocated this
904 					   device */
905 	void		*platform_data;	/* Platform specific data, device
906 					   core doesn't touch it */
907 	void		*driver_data;	/* Driver data, set and get with
908 					   dev_set/get_drvdata */
909 	struct dev_links_info	links;
910 	struct dev_pm_info	power;
911 	struct dev_pm_domain	*pm_domain;
912 
913 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
914 	struct irq_domain	*msi_domain;
915 #endif
916 #ifdef CONFIG_PINCTRL
917 	struct dev_pin_info	*pins;
918 #endif
919 #ifdef CONFIG_GENERIC_MSI_IRQ
920 	struct list_head	msi_list;
921 #endif
922 
923 #ifdef CONFIG_NUMA
924 	int		numa_node;	/* NUMA node this device is close to */
925 #endif
926 	const struct dma_map_ops *dma_ops;
927 	u64		*dma_mask;	/* dma mask (if dma'able device) */
928 	u64		coherent_dma_mask;/* Like dma_mask, but for
929 					     alloc_coherent mappings as
930 					     not all hardware supports
931 					     64 bit addresses for consistent
932 					     allocations such descriptors. */
933 	unsigned long	dma_pfn_offset;
934 
935 	struct device_dma_parameters *dma_parms;
936 
937 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
938 
939 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
940 					     override */
941 #ifdef CONFIG_DMA_CMA
942 	struct cma *cma_area;		/* contiguous memory area for dma
943 					   allocations */
944 #endif
945 	/* arch specific additions */
946 	struct dev_archdata	archdata;
947 
948 	struct device_node	*of_node; /* associated device tree node */
949 	struct fwnode_handle	*fwnode; /* firmware device node */
950 
951 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
952 	u32			id;	/* device instance */
953 
954 	spinlock_t		devres_lock;
955 	struct list_head	devres_head;
956 
957 	struct klist_node	knode_class;
958 	struct class		*class;
959 	const struct attribute_group **groups;	/* optional groups */
960 
961 	void	(*release)(struct device *dev);
962 	struct iommu_group	*iommu_group;
963 	struct iommu_fwspec	*iommu_fwspec;
964 
965 	bool			offline_disabled:1;
966 	bool			offline:1;
967 	bool			of_node_reused:1;
968 };
969 
kobj_to_dev(struct kobject * kobj)970 static inline struct device *kobj_to_dev(struct kobject *kobj)
971 {
972 	return container_of(kobj, struct device, kobj);
973 }
974 
975 /* Get the wakeup routines, which depend on struct device */
976 #include <linux/pm_wakeup.h>
977 
dev_name(const struct device * dev)978 static inline const char *dev_name(const struct device *dev)
979 {
980 	/* Use the init name until the kobject becomes available */
981 	if (dev->init_name)
982 		return dev->init_name;
983 
984 	return kobject_name(&dev->kobj);
985 }
986 
987 extern __printf(2, 3)
988 int dev_set_name(struct device *dev, const char *name, ...);
989 
990 #ifdef CONFIG_NUMA
dev_to_node(struct device * dev)991 static inline int dev_to_node(struct device *dev)
992 {
993 	return dev->numa_node;
994 }
set_dev_node(struct device * dev,int node)995 static inline void set_dev_node(struct device *dev, int node)
996 {
997 	dev->numa_node = node;
998 }
999 #else
dev_to_node(struct device * dev)1000 static inline int dev_to_node(struct device *dev)
1001 {
1002 	return -1;
1003 }
set_dev_node(struct device * dev,int node)1004 static inline void set_dev_node(struct device *dev, int node)
1005 {
1006 }
1007 #endif
1008 
dev_get_msi_domain(const struct device * dev)1009 static inline struct irq_domain *dev_get_msi_domain(const struct device *dev)
1010 {
1011 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
1012 	return dev->msi_domain;
1013 #else
1014 	return NULL;
1015 #endif
1016 }
1017 
dev_set_msi_domain(struct device * dev,struct irq_domain * d)1018 static inline void dev_set_msi_domain(struct device *dev, struct irq_domain *d)
1019 {
1020 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
1021 	dev->msi_domain = d;
1022 #endif
1023 }
1024 
dev_get_drvdata(const struct device * dev)1025 static inline void *dev_get_drvdata(const struct device *dev)
1026 {
1027 	return dev->driver_data;
1028 }
1029 
dev_set_drvdata(struct device * dev,void * data)1030 static inline void dev_set_drvdata(struct device *dev, void *data)
1031 {
1032 	dev->driver_data = data;
1033 }
1034 
dev_to_psd(struct device * dev)1035 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
1036 {
1037 	return dev ? dev->power.subsys_data : NULL;
1038 }
1039 
dev_get_uevent_suppress(const struct device * dev)1040 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
1041 {
1042 	return dev->kobj.uevent_suppress;
1043 }
1044 
dev_set_uevent_suppress(struct device * dev,int val)1045 static inline void dev_set_uevent_suppress(struct device *dev, int val)
1046 {
1047 	dev->kobj.uevent_suppress = val;
1048 }
1049 
device_is_registered(struct device * dev)1050 static inline int device_is_registered(struct device *dev)
1051 {
1052 	return dev->kobj.state_in_sysfs;
1053 }
1054 
device_enable_async_suspend(struct device * dev)1055 static inline void device_enable_async_suspend(struct device *dev)
1056 {
1057 	if (!dev->power.is_prepared)
1058 		dev->power.async_suspend = true;
1059 }
1060 
device_disable_async_suspend(struct device * dev)1061 static inline void device_disable_async_suspend(struct device *dev)
1062 {
1063 	if (!dev->power.is_prepared)
1064 		dev->power.async_suspend = false;
1065 }
1066 
device_async_suspend_enabled(struct device * dev)1067 static inline bool device_async_suspend_enabled(struct device *dev)
1068 {
1069 	return !!dev->power.async_suspend;
1070 }
1071 
dev_pm_syscore_device(struct device * dev,bool val)1072 static inline void dev_pm_syscore_device(struct device *dev, bool val)
1073 {
1074 #ifdef CONFIG_PM_SLEEP
1075 	dev->power.syscore = val;
1076 #endif
1077 }
1078 
device_lock(struct device * dev)1079 static inline void device_lock(struct device *dev)
1080 {
1081 	mutex_lock(&dev->mutex);
1082 }
1083 
device_lock_interruptible(struct device * dev)1084 static inline int device_lock_interruptible(struct device *dev)
1085 {
1086 	return mutex_lock_interruptible(&dev->mutex);
1087 }
1088 
device_trylock(struct device * dev)1089 static inline int device_trylock(struct device *dev)
1090 {
1091 	return mutex_trylock(&dev->mutex);
1092 }
1093 
device_unlock(struct device * dev)1094 static inline void device_unlock(struct device *dev)
1095 {
1096 	mutex_unlock(&dev->mutex);
1097 }
1098 
device_lock_assert(struct device * dev)1099 static inline void device_lock_assert(struct device *dev)
1100 {
1101 	lockdep_assert_held(&dev->mutex);
1102 }
1103 
dev_of_node(struct device * dev)1104 static inline struct device_node *dev_of_node(struct device *dev)
1105 {
1106 	if (!IS_ENABLED(CONFIG_OF))
1107 		return NULL;
1108 	return dev->of_node;
1109 }
1110 
1111 void driver_init(void);
1112 
1113 /*
1114  * High level routines for use by the bus drivers
1115  */
1116 extern int __must_check device_register(struct device *dev);
1117 extern void device_unregister(struct device *dev);
1118 extern void device_initialize(struct device *dev);
1119 extern int __must_check device_add(struct device *dev);
1120 extern void device_del(struct device *dev);
1121 extern int device_for_each_child(struct device *dev, void *data,
1122 		     int (*fn)(struct device *dev, void *data));
1123 extern int device_for_each_child_reverse(struct device *dev, void *data,
1124 		     int (*fn)(struct device *dev, void *data));
1125 extern struct device *device_find_child(struct device *dev, void *data,
1126 				int (*match)(struct device *dev, void *data));
1127 extern int device_rename(struct device *dev, const char *new_name);
1128 extern int device_move(struct device *dev, struct device *new_parent,
1129 		       enum dpm_order dpm_order);
1130 extern const char *device_get_devnode(struct device *dev,
1131 				      umode_t *mode, kuid_t *uid, kgid_t *gid,
1132 				      const char **tmp);
1133 
device_supports_offline(struct device * dev)1134 static inline bool device_supports_offline(struct device *dev)
1135 {
1136 	return dev->bus && dev->bus->offline && dev->bus->online;
1137 }
1138 
1139 extern void lock_device_hotplug(void);
1140 extern void unlock_device_hotplug(void);
1141 extern int lock_device_hotplug_sysfs(void);
1142 extern int device_offline(struct device *dev);
1143 extern int device_online(struct device *dev);
1144 extern void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1145 extern void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1146 void device_set_of_node_from_dev(struct device *dev, const struct device *dev2);
1147 
dev_num_vf(struct device * dev)1148 static inline int dev_num_vf(struct device *dev)
1149 {
1150 	if (dev->bus && dev->bus->num_vf)
1151 		return dev->bus->num_vf(dev);
1152 	return 0;
1153 }
1154 
1155 /*
1156  * Root device objects for grouping under /sys/devices
1157  */
1158 extern struct device *__root_device_register(const char *name,
1159 					     struct module *owner);
1160 
1161 /* This is a macro to avoid include problems with THIS_MODULE */
1162 #define root_device_register(name) \
1163 	__root_device_register(name, THIS_MODULE)
1164 
1165 extern void root_device_unregister(struct device *root);
1166 
dev_get_platdata(const struct device * dev)1167 static inline void *dev_get_platdata(const struct device *dev)
1168 {
1169 	return dev->platform_data;
1170 }
1171 
1172 /*
1173  * Manual binding of a device to driver. See drivers/base/bus.c
1174  * for information on use.
1175  */
1176 extern int __must_check device_bind_driver(struct device *dev);
1177 extern void device_release_driver(struct device *dev);
1178 extern int  __must_check device_attach(struct device *dev);
1179 extern int __must_check driver_attach(struct device_driver *drv);
1180 extern void device_initial_probe(struct device *dev);
1181 extern int __must_check device_reprobe(struct device *dev);
1182 
1183 extern bool device_is_bound(struct device *dev);
1184 
1185 /*
1186  * Easy functions for dynamically creating devices on the fly
1187  */
1188 extern __printf(5, 0)
1189 struct device *device_create_vargs(struct class *cls, struct device *parent,
1190 				   dev_t devt, void *drvdata,
1191 				   const char *fmt, va_list vargs);
1192 extern __printf(5, 6)
1193 struct device *device_create(struct class *cls, struct device *parent,
1194 			     dev_t devt, void *drvdata,
1195 			     const char *fmt, ...);
1196 extern __printf(6, 7)
1197 struct device *device_create_with_groups(struct class *cls,
1198 			     struct device *parent, dev_t devt, void *drvdata,
1199 			     const struct attribute_group **groups,
1200 			     const char *fmt, ...);
1201 extern void device_destroy(struct class *cls, dev_t devt);
1202 
1203 extern int __must_check device_add_groups(struct device *dev,
1204 					const struct attribute_group **groups);
1205 extern void device_remove_groups(struct device *dev,
1206 				 const struct attribute_group **groups);
1207 
device_add_group(struct device * dev,const struct attribute_group * grp)1208 static inline int __must_check device_add_group(struct device *dev,
1209 					const struct attribute_group *grp)
1210 {
1211 	const struct attribute_group *groups[] = { grp, NULL };
1212 
1213 	return device_add_groups(dev, groups);
1214 }
1215 
device_remove_group(struct device * dev,const struct attribute_group * grp)1216 static inline void device_remove_group(struct device *dev,
1217 				       const struct attribute_group *grp)
1218 {
1219 	const struct attribute_group *groups[] = { grp, NULL };
1220 
1221 	return device_remove_groups(dev, groups);
1222 }
1223 
1224 extern int __must_check devm_device_add_groups(struct device *dev,
1225 					const struct attribute_group **groups);
1226 extern void devm_device_remove_groups(struct device *dev,
1227 				      const struct attribute_group **groups);
1228 extern int __must_check devm_device_add_group(struct device *dev,
1229 					const struct attribute_group *grp);
1230 extern void devm_device_remove_group(struct device *dev,
1231 				     const struct attribute_group *grp);
1232 
1233 /*
1234  * Platform "fixup" functions - allow the platform to have their say
1235  * about devices and actions that the general device layer doesn't
1236  * know about.
1237  */
1238 /* Notify platform of device discovery */
1239 extern int (*platform_notify)(struct device *dev);
1240 
1241 extern int (*platform_notify_remove)(struct device *dev);
1242 
1243 
1244 /*
1245  * get_device - atomically increment the reference count for the device.
1246  *
1247  */
1248 extern struct device *get_device(struct device *dev);
1249 extern void put_device(struct device *dev);
1250 
1251 #ifdef CONFIG_DEVTMPFS
1252 extern int devtmpfs_create_node(struct device *dev);
1253 extern int devtmpfs_delete_node(struct device *dev);
1254 extern int devtmpfs_mount(const char *mntdir);
1255 #else
devtmpfs_create_node(struct device * dev)1256 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
devtmpfs_delete_node(struct device * dev)1257 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
devtmpfs_mount(const char * mountpoint)1258 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
1259 #endif
1260 
1261 /* drivers/base/power/shutdown.c */
1262 extern void device_shutdown(void);
1263 
1264 /* debugging and troubleshooting/diagnostic helpers. */
1265 extern const char *dev_driver_string(const struct device *dev);
1266 
1267 /* Device links interface. */
1268 struct device_link *device_link_add(struct device *consumer,
1269 				    struct device *supplier, u32 flags);
1270 void device_link_del(struct device_link *link);
1271 
1272 #ifdef CONFIG_PRINTK
1273 
1274 extern __printf(3, 0)
1275 int dev_vprintk_emit(int level, const struct device *dev,
1276 		     const char *fmt, va_list args);
1277 extern __printf(3, 4)
1278 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...);
1279 
1280 extern __printf(3, 4)
1281 void dev_printk(const char *level, const struct device *dev,
1282 		const char *fmt, ...);
1283 extern __printf(2, 3)
1284 void dev_emerg(const struct device *dev, const char *fmt, ...);
1285 extern __printf(2, 3)
1286 void dev_alert(const struct device *dev, const char *fmt, ...);
1287 extern __printf(2, 3)
1288 void dev_crit(const struct device *dev, const char *fmt, ...);
1289 extern __printf(2, 3)
1290 void dev_err(const struct device *dev, const char *fmt, ...);
1291 extern __printf(2, 3)
1292 void dev_warn(const struct device *dev, const char *fmt, ...);
1293 extern __printf(2, 3)
1294 void dev_notice(const struct device *dev, const char *fmt, ...);
1295 extern __printf(2, 3)
1296 void _dev_info(const struct device *dev, const char *fmt, ...);
1297 
1298 #else
1299 
1300 static inline __printf(3, 0)
dev_vprintk_emit(int level,const struct device * dev,const char * fmt,va_list args)1301 int dev_vprintk_emit(int level, const struct device *dev,
1302 		     const char *fmt, va_list args)
1303 { return 0; }
1304 static inline __printf(3, 4)
dev_printk_emit(int level,const struct device * dev,const char * fmt,...)1305 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
1306 { return 0; }
1307 
__dev_printk(const char * level,const struct device * dev,struct va_format * vaf)1308 static inline void __dev_printk(const char *level, const struct device *dev,
1309 				struct va_format *vaf)
1310 {}
1311 static inline __printf(3, 4)
dev_printk(const char * level,const struct device * dev,const char * fmt,...)1312 void dev_printk(const char *level, const struct device *dev,
1313 		const char *fmt, ...)
1314 {}
1315 
1316 static inline __printf(2, 3)
dev_emerg(const struct device * dev,const char * fmt,...)1317 void dev_emerg(const struct device *dev, const char *fmt, ...)
1318 {}
1319 static inline __printf(2, 3)
dev_crit(const struct device * dev,const char * fmt,...)1320 void dev_crit(const struct device *dev, const char *fmt, ...)
1321 {}
1322 static inline __printf(2, 3)
dev_alert(const struct device * dev,const char * fmt,...)1323 void dev_alert(const struct device *dev, const char *fmt, ...)
1324 {}
1325 static inline __printf(2, 3)
dev_err(const struct device * dev,const char * fmt,...)1326 void dev_err(const struct device *dev, const char *fmt, ...)
1327 {}
1328 static inline __printf(2, 3)
dev_warn(const struct device * dev,const char * fmt,...)1329 void dev_warn(const struct device *dev, const char *fmt, ...)
1330 {}
1331 static inline __printf(2, 3)
dev_notice(const struct device * dev,const char * fmt,...)1332 void dev_notice(const struct device *dev, const char *fmt, ...)
1333 {}
1334 static inline __printf(2, 3)
_dev_info(const struct device * dev,const char * fmt,...)1335 void _dev_info(const struct device *dev, const char *fmt, ...)
1336 {}
1337 
1338 #endif
1339 
1340 /*
1341  * Stupid hackaround for existing uses of non-printk uses dev_info
1342  *
1343  * Note that the definition of dev_info below is actually _dev_info
1344  * and a macro is used to avoid redefining dev_info
1345  */
1346 
1347 #define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)
1348 
1349 #if defined(CONFIG_DYNAMIC_DEBUG)
1350 #define dev_dbg(dev, format, ...)		     \
1351 do {						     \
1352 	dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
1353 } while (0)
1354 #elif defined(DEBUG)
1355 #define dev_dbg(dev, format, arg...)		\
1356 	dev_printk(KERN_DEBUG, dev, format, ##arg)
1357 #else
1358 #define dev_dbg(dev, format, arg...)				\
1359 ({								\
1360 	if (0)							\
1361 		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
1362 })
1363 #endif
1364 
1365 #ifdef CONFIG_PRINTK
1366 #define dev_level_once(dev_level, dev, fmt, ...)			\
1367 do {									\
1368 	static bool __print_once __read_mostly;				\
1369 									\
1370 	if (!__print_once) {						\
1371 		__print_once = true;					\
1372 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1373 	}								\
1374 } while (0)
1375 #else
1376 #define dev_level_once(dev_level, dev, fmt, ...)			\
1377 do {									\
1378 	if (0)								\
1379 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1380 } while (0)
1381 #endif
1382 
1383 #define dev_emerg_once(dev, fmt, ...)					\
1384 	dev_level_once(dev_emerg, dev, fmt, ##__VA_ARGS__)
1385 #define dev_alert_once(dev, fmt, ...)					\
1386 	dev_level_once(dev_alert, dev, fmt, ##__VA_ARGS__)
1387 #define dev_crit_once(dev, fmt, ...)					\
1388 	dev_level_once(dev_crit, dev, fmt, ##__VA_ARGS__)
1389 #define dev_err_once(dev, fmt, ...)					\
1390 	dev_level_once(dev_err, dev, fmt, ##__VA_ARGS__)
1391 #define dev_warn_once(dev, fmt, ...)					\
1392 	dev_level_once(dev_warn, dev, fmt, ##__VA_ARGS__)
1393 #define dev_notice_once(dev, fmt, ...)					\
1394 	dev_level_once(dev_notice, dev, fmt, ##__VA_ARGS__)
1395 #define dev_info_once(dev, fmt, ...)					\
1396 	dev_level_once(dev_info, dev, fmt, ##__VA_ARGS__)
1397 #define dev_dbg_once(dev, fmt, ...)					\
1398 	dev_level_once(dev_dbg, dev, fmt, ##__VA_ARGS__)
1399 
1400 #define dev_level_ratelimited(dev_level, dev, fmt, ...)			\
1401 do {									\
1402 	static DEFINE_RATELIMIT_STATE(_rs,				\
1403 				      DEFAULT_RATELIMIT_INTERVAL,	\
1404 				      DEFAULT_RATELIMIT_BURST);		\
1405 	if (__ratelimit(&_rs))						\
1406 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1407 } while (0)
1408 
1409 #define dev_emerg_ratelimited(dev, fmt, ...)				\
1410 	dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__)
1411 #define dev_alert_ratelimited(dev, fmt, ...)				\
1412 	dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__)
1413 #define dev_crit_ratelimited(dev, fmt, ...)				\
1414 	dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__)
1415 #define dev_err_ratelimited(dev, fmt, ...)				\
1416 	dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__)
1417 #define dev_warn_ratelimited(dev, fmt, ...)				\
1418 	dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__)
1419 #define dev_notice_ratelimited(dev, fmt, ...)				\
1420 	dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__)
1421 #define dev_info_ratelimited(dev, fmt, ...)				\
1422 	dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__)
1423 #if defined(CONFIG_DYNAMIC_DEBUG)
1424 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
1425 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1426 do {									\
1427 	static DEFINE_RATELIMIT_STATE(_rs,				\
1428 				      DEFAULT_RATELIMIT_INTERVAL,	\
1429 				      DEFAULT_RATELIMIT_BURST);		\
1430 	DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);			\
1431 	if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) &&	\
1432 	    __ratelimit(&_rs))						\
1433 		__dynamic_dev_dbg(&descriptor, dev, fmt,		\
1434 				  ##__VA_ARGS__);			\
1435 } while (0)
1436 #elif defined(DEBUG)
1437 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1438 do {									\
1439 	static DEFINE_RATELIMIT_STATE(_rs,				\
1440 				      DEFAULT_RATELIMIT_INTERVAL,	\
1441 				      DEFAULT_RATELIMIT_BURST);		\
1442 	if (__ratelimit(&_rs))						\
1443 		dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__);	\
1444 } while (0)
1445 #else
1446 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1447 do {									\
1448 	if (0)								\
1449 		dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__);	\
1450 } while (0)
1451 #endif
1452 
1453 #ifdef VERBOSE_DEBUG
1454 #define dev_vdbg	dev_dbg
1455 #else
1456 #define dev_vdbg(dev, format, arg...)				\
1457 ({								\
1458 	if (0)							\
1459 		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
1460 })
1461 #endif
1462 
1463 /*
1464  * dev_WARN*() acts like dev_printk(), but with the key difference of
1465  * using WARN/WARN_ONCE to include file/line information and a backtrace.
1466  */
1467 #define dev_WARN(dev, format, arg...) \
1468 	WARN(1, "%s %s: " format, dev_driver_string(dev), dev_name(dev), ## arg);
1469 
1470 #define dev_WARN_ONCE(dev, condition, format, arg...) \
1471 	WARN_ONCE(condition, "%s %s: " format, \
1472 			dev_driver_string(dev), dev_name(dev), ## arg)
1473 
1474 /* Create alias, so I can be autoloaded. */
1475 #define MODULE_ALIAS_CHARDEV(major,minor) \
1476 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1477 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1478 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
1479 
1480 #ifdef CONFIG_SYSFS_DEPRECATED
1481 extern long sysfs_deprecated;
1482 #else
1483 #define sysfs_deprecated 0
1484 #endif
1485 
1486 /**
1487  * module_driver() - Helper macro for drivers that don't do anything
1488  * special in module init/exit. This eliminates a lot of boilerplate.
1489  * Each module may only use this macro once, and calling it replaces
1490  * module_init() and module_exit().
1491  *
1492  * @__driver: driver name
1493  * @__register: register function for this driver type
1494  * @__unregister: unregister function for this driver type
1495  * @...: Additional arguments to be passed to __register and __unregister.
1496  *
1497  * Use this macro to construct bus specific macros for registering
1498  * drivers, and do not use it on its own.
1499  */
1500 #define module_driver(__driver, __register, __unregister, ...) \
1501 static int __init __driver##_init(void) \
1502 { \
1503 	return __register(&(__driver) , ##__VA_ARGS__); \
1504 } \
1505 module_init(__driver##_init); \
1506 static void __exit __driver##_exit(void) \
1507 { \
1508 	__unregister(&(__driver) , ##__VA_ARGS__); \
1509 } \
1510 module_exit(__driver##_exit);
1511 
1512 /**
1513  * builtin_driver() - Helper macro for drivers that don't do anything
1514  * special in init and have no exit. This eliminates some boilerplate.
1515  * Each driver may only use this macro once, and calling it replaces
1516  * device_initcall (or in some cases, the legacy __initcall).  This is
1517  * meant to be a direct parallel of module_driver() above but without
1518  * the __exit stuff that is not used for builtin cases.
1519  *
1520  * @__driver: driver name
1521  * @__register: register function for this driver type
1522  * @...: Additional arguments to be passed to __register
1523  *
1524  * Use this macro to construct bus specific macros for registering
1525  * drivers, and do not use it on its own.
1526  */
1527 #define builtin_driver(__driver, __register, ...) \
1528 static int __init __driver##_init(void) \
1529 { \
1530 	return __register(&(__driver) , ##__VA_ARGS__); \
1531 } \
1532 device_initcall(__driver##_init);
1533 
1534 #endif /* _DEVICE_H_ */
1535