xref: /linux-6.15/include/linux/device.h (revision 02bc11de)
1 /*
2  * device.h - generic, centralized driver model
3  *
4  * Copyright (c) 2001-2003 Patrick Mochel <[email protected]>
5  * Copyright (c) 2004-2009 Greg Kroah-Hartman <[email protected]>
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  * @dev_attrs:	Default attributes of the devices on the bus.
70  * @bus_groups:	Default attributes of the bus.
71  * @dev_groups:	Default attributes of the devices on the bus.
72  * @drv_groups: Default attributes of the device drivers on the bus.
73  * @match:	Called, perhaps multiple times, whenever a new device or driver
74  *		is added for this bus. It should return a positive value if the
75  *		given device can be handled by the given driver and zero
76  *		otherwise. It may also return error code if determining that
77  *		the driver supports the device is not possible. In case of
78  *		-EPROBE_DEFER it will queue the device for deferred probing.
79  * @uevent:	Called when a device is added, removed, or a few other things
80  *		that generate uevents to add the environment variables.
81  * @probe:	Called when a new device or driver add to this bus, and callback
82  *		the specific driver's probe to initial the matched device.
83  * @remove:	Called when a device removed from this bus.
84  * @shutdown:	Called at shut-down time to quiesce the device.
85  *
86  * @online:	Called to put the device back online (after offlining it).
87  * @offline:	Called to put the device offline for hot-removal. May fail.
88  *
89  * @suspend:	Called when a device on this bus wants to go to sleep mode.
90  * @resume:	Called to bring a device on this bus out of sleep mode.
91  * @pm:		Power management operations of this bus, callback the specific
92  *		device driver's pm-ops.
93  * @iommu_ops:  IOMMU specific operations for this bus, used to attach IOMMU
94  *              driver implementations to a bus and allow the driver to do
95  *              bus-specific setup
96  * @p:		The private data of the driver core, only the driver core can
97  *		touch this.
98  * @lock_key:	Lock class key for use by the lock validator
99  *
100  * A bus is a channel between the processor and one or more devices. For the
101  * purposes of the device model, all devices are connected via a bus, even if
102  * it is an internal, virtual, "platform" bus. Buses can plug into each other.
103  * A USB controller is usually a PCI device, for example. The device model
104  * represents the actual connections between buses and the devices they control.
105  * A bus is represented by the bus_type structure. It contains the name, the
106  * default attributes, the bus' methods, PM operations, and the driver core's
107  * private data.
108  */
109 struct bus_type {
110 	const char		*name;
111 	const char		*dev_name;
112 	struct device		*dev_root;
113 	struct device_attribute	*dev_attrs;	/* use dev_groups instead */
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 	const struct dev_pm_ops *pm;
131 
132 	const struct iommu_ops *iommu_ops;
133 
134 	struct subsys_private *p;
135 	struct lock_class_key lock_key;
136 };
137 
138 extern int __must_check bus_register(struct bus_type *bus);
139 
140 extern void bus_unregister(struct bus_type *bus);
141 
142 extern int __must_check bus_rescan_devices(struct bus_type *bus);
143 
144 /* iterator helpers for buses */
145 struct subsys_dev_iter {
146 	struct klist_iter		ki;
147 	const struct device_type	*type;
148 };
149 void subsys_dev_iter_init(struct subsys_dev_iter *iter,
150 			 struct bus_type *subsys,
151 			 struct device *start,
152 			 const struct device_type *type);
153 struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter);
154 void subsys_dev_iter_exit(struct subsys_dev_iter *iter);
155 
156 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
157 		     int (*fn)(struct device *dev, void *data));
158 struct device *bus_find_device(struct bus_type *bus, struct device *start,
159 			       void *data,
160 			       int (*match)(struct device *dev, void *data));
161 struct device *bus_find_device_by_name(struct bus_type *bus,
162 				       struct device *start,
163 				       const char *name);
164 struct device *subsys_find_device_by_id(struct bus_type *bus, unsigned int id,
165 					struct device *hint);
166 int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
167 		     void *data, int (*fn)(struct device_driver *, void *));
168 void bus_sort_breadthfirst(struct bus_type *bus,
169 			   int (*compare)(const struct device *a,
170 					  const struct device *b));
171 /*
172  * Bus notifiers: Get notified of addition/removal of devices
173  * and binding/unbinding of drivers to devices.
174  * In the long run, it should be a replacement for the platform
175  * notify hooks.
176  */
177 struct notifier_block;
178 
179 extern int bus_register_notifier(struct bus_type *bus,
180 				 struct notifier_block *nb);
181 extern int bus_unregister_notifier(struct bus_type *bus,
182 				   struct notifier_block *nb);
183 
184 /* All 4 notifers below get called with the target struct device *
185  * as an argument. Note that those functions are likely to be called
186  * with the device lock held in the core, so be careful.
187  */
188 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
189 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device to be removed */
190 #define BUS_NOTIFY_REMOVED_DEVICE	0x00000003 /* device removed */
191 #define BUS_NOTIFY_BIND_DRIVER		0x00000004 /* driver about to be
192 						      bound */
193 #define BUS_NOTIFY_BOUND_DRIVER		0x00000005 /* driver bound to device */
194 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000006 /* driver about to be
195 						      unbound */
196 #define BUS_NOTIFY_UNBOUND_DRIVER	0x00000007 /* driver is unbound
197 						      from the device */
198 #define BUS_NOTIFY_DRIVER_NOT_BOUND	0x00000008 /* driver fails to be bound */
199 
200 extern struct kset *bus_get_kset(struct bus_type *bus);
201 extern struct klist *bus_get_device_klist(struct bus_type *bus);
202 
203 /**
204  * enum probe_type - device driver probe type to try
205  *	Device drivers may opt in for special handling of their
206  *	respective probe routines. This tells the core what to
207  *	expect and prefer.
208  *
209  * @PROBE_DEFAULT_STRATEGY: Used by drivers that work equally well
210  *	whether probed synchronously or asynchronously.
211  * @PROBE_PREFER_ASYNCHRONOUS: Drivers for "slow" devices which
212  *	probing order is not essential for booting the system may
213  *	opt into executing their probes asynchronously.
214  * @PROBE_FORCE_SYNCHRONOUS: Use this to annotate drivers that need
215  *	their probe routines to run synchronously with driver and
216  *	device registration (with the exception of -EPROBE_DEFER
217  *	handling - re-probing always ends up being done asynchronously).
218  *
219  * Note that the end goal is to switch the kernel to use asynchronous
220  * probing by default, so annotating drivers with
221  * %PROBE_PREFER_ASYNCHRONOUS is a temporary measure that allows us
222  * to speed up boot process while we are validating the rest of the
223  * drivers.
224  */
225 enum probe_type {
226 	PROBE_DEFAULT_STRATEGY,
227 	PROBE_PREFER_ASYNCHRONOUS,
228 	PROBE_FORCE_SYNCHRONOUS,
229 };
230 
231 /**
232  * struct device_driver - The basic device driver structure
233  * @name:	Name of the device driver.
234  * @bus:	The bus which the device of this driver belongs to.
235  * @owner:	The module owner.
236  * @mod_name:	Used for built-in modules.
237  * @suppress_bind_attrs: Disables bind/unbind via sysfs.
238  * @probe_type:	Type of the probe (synchronous or asynchronous) to use.
239  * @of_match_table: The open firmware table.
240  * @acpi_match_table: The ACPI match table.
241  * @probe:	Called to query the existence of a specific device,
242  *		whether this driver can work with it, and bind the driver
243  *		to a specific device.
244  * @remove:	Called when the device is removed from the system to
245  *		unbind a device from this driver.
246  * @shutdown:	Called at shut-down time to quiesce the device.
247  * @suspend:	Called to put the device to sleep mode. Usually to a
248  *		low power state.
249  * @resume:	Called to bring a device from sleep mode.
250  * @groups:	Default attributes that get created by the driver core
251  *		automatically.
252  * @pm:		Power management operations of the device which matched
253  *		this driver.
254  * @p:		Driver core's private data, no one other than the driver
255  *		core can touch this.
256  *
257  * The device driver-model tracks all of the drivers known to the system.
258  * The main reason for this tracking is to enable the driver core to match
259  * up drivers with new devices. Once drivers are known objects within the
260  * system, however, a number of other things become possible. Device drivers
261  * can export information and configuration variables that are independent
262  * of any specific device.
263  */
264 struct device_driver {
265 	const char		*name;
266 	struct bus_type		*bus;
267 
268 	struct module		*owner;
269 	const char		*mod_name;	/* used for built-in modules */
270 
271 	bool suppress_bind_attrs;	/* disables bind/unbind via sysfs */
272 	enum probe_type probe_type;
273 
274 	const struct of_device_id	*of_match_table;
275 	const struct acpi_device_id	*acpi_match_table;
276 
277 	int (*probe) (struct device *dev);
278 	int (*remove) (struct device *dev);
279 	void (*shutdown) (struct device *dev);
280 	int (*suspend) (struct device *dev, pm_message_t state);
281 	int (*resume) (struct device *dev);
282 	const struct attribute_group **groups;
283 
284 	const struct dev_pm_ops *pm;
285 
286 	struct driver_private *p;
287 };
288 
289 
290 extern int __must_check driver_register(struct device_driver *drv);
291 extern void driver_unregister(struct device_driver *drv);
292 
293 extern struct device_driver *driver_find(const char *name,
294 					 struct bus_type *bus);
295 extern int driver_probe_done(void);
296 extern void wait_for_device_probe(void);
297 
298 
299 /* sysfs interface for exporting driver attributes */
300 
301 struct driver_attribute {
302 	struct attribute attr;
303 	ssize_t (*show)(struct device_driver *driver, char *buf);
304 	ssize_t (*store)(struct device_driver *driver, const char *buf,
305 			 size_t count);
306 };
307 
308 #define DRIVER_ATTR(_name, _mode, _show, _store) \
309 	struct driver_attribute driver_attr_##_name = __ATTR(_name, _mode, _show, _store)
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_attrs: 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  * @ns_type:	Callbacks so sysfs can detemine namespaces.
377  * @namespace:	Namespace of the device belongs to this class.
378  * @pm:		The default device power management operations of this class.
379  * @p:		The private data of the driver core, no one other than the
380  *		driver core can touch this.
381  *
382  * A class is a higher-level view of a device that abstracts out low-level
383  * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
384  * at the class level, they are all simply disks. Classes allow user space
385  * to work with devices based on what they do, rather than how they are
386  * connected or how they work.
387  */
388 struct class {
389 	const char		*name;
390 	struct module		*owner;
391 
392 	struct class_attribute		*class_attrs;
393 	const struct attribute_group	**dev_groups;
394 	struct kobject			*dev_kobj;
395 
396 	int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
397 	char *(*devnode)(struct device *dev, umode_t *mode);
398 
399 	void (*class_release)(struct class *class);
400 	void (*dev_release)(struct device *dev);
401 
402 	int (*suspend)(struct device *dev, pm_message_t state);
403 	int (*resume)(struct device *dev);
404 
405 	const struct kobj_ns_type_operations *ns_type;
406 	const void *(*namespace)(struct device *dev);
407 
408 	const struct dev_pm_ops *pm;
409 
410 	struct subsys_private *p;
411 };
412 
413 struct class_dev_iter {
414 	struct klist_iter		ki;
415 	const struct device_type	*type;
416 };
417 
418 extern struct kobject *sysfs_dev_block_kobj;
419 extern struct kobject *sysfs_dev_char_kobj;
420 extern int __must_check __class_register(struct class *class,
421 					 struct lock_class_key *key);
422 extern void class_unregister(struct class *class);
423 
424 /* This is a #define to keep the compiler from merging different
425  * instances of the __key variable */
426 #define class_register(class)			\
427 ({						\
428 	static struct lock_class_key __key;	\
429 	__class_register(class, &__key);	\
430 })
431 
432 struct class_compat;
433 struct class_compat *class_compat_register(const char *name);
434 void class_compat_unregister(struct class_compat *cls);
435 int class_compat_create_link(struct class_compat *cls, struct device *dev,
436 			     struct device *device_link);
437 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
438 			      struct device *device_link);
439 
440 extern void class_dev_iter_init(struct class_dev_iter *iter,
441 				struct class *class,
442 				struct device *start,
443 				const struct device_type *type);
444 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
445 extern void class_dev_iter_exit(struct class_dev_iter *iter);
446 
447 extern int class_for_each_device(struct class *class, struct device *start,
448 				 void *data,
449 				 int (*fn)(struct device *dev, void *data));
450 extern struct device *class_find_device(struct class *class,
451 					struct device *start, const void *data,
452 					int (*match)(struct device *, const void *));
453 
454 struct class_attribute {
455 	struct attribute attr;
456 	ssize_t (*show)(struct class *class, struct class_attribute *attr,
457 			char *buf);
458 	ssize_t (*store)(struct class *class, struct class_attribute *attr,
459 			const char *buf, size_t count);
460 };
461 
462 #define CLASS_ATTR(_name, _mode, _show, _store) \
463 	struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
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 
469 extern int __must_check class_create_file_ns(struct class *class,
470 					     const struct class_attribute *attr,
471 					     const void *ns);
472 extern void class_remove_file_ns(struct class *class,
473 				 const struct class_attribute *attr,
474 				 const void *ns);
475 
476 static inline int __must_check class_create_file(struct class *class,
477 					const struct class_attribute *attr)
478 {
479 	return class_create_file_ns(class, attr, NULL);
480 }
481 
482 static inline void class_remove_file(struct class *class,
483 				     const struct class_attribute *attr)
484 {
485 	return class_remove_file_ns(class, attr, NULL);
486 }
487 
488 /* Simple class attribute that is just a static string */
489 struct class_attribute_string {
490 	struct class_attribute attr;
491 	char *str;
492 };
493 
494 /* Currently read-only only */
495 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
496 	{ __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
497 #define CLASS_ATTR_STRING(_name, _mode, _str) \
498 	struct class_attribute_string class_attr_##_name = \
499 		_CLASS_ATTR_STRING(_name, _mode, _str)
500 
501 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
502                         char *buf);
503 
504 struct class_interface {
505 	struct list_head	node;
506 	struct class		*class;
507 
508 	int (*add_dev)		(struct device *, struct class_interface *);
509 	void (*remove_dev)	(struct device *, struct class_interface *);
510 };
511 
512 extern int __must_check class_interface_register(struct class_interface *);
513 extern void class_interface_unregister(struct class_interface *);
514 
515 extern struct class * __must_check __class_create(struct module *owner,
516 						  const char *name,
517 						  struct lock_class_key *key);
518 extern void class_destroy(struct class *cls);
519 
520 /* This is a #define to keep the compiler from merging different
521  * instances of the __key variable */
522 #define class_create(owner, name)		\
523 ({						\
524 	static struct lock_class_key __key;	\
525 	__class_create(owner, name, &__key);	\
526 })
527 
528 /*
529  * The type of device, "struct device" is embedded in. A class
530  * or bus can contain devices of different types
531  * like "partitions" and "disks", "mouse" and "event".
532  * This identifies the device type and carries type-specific
533  * information, equivalent to the kobj_type of a kobject.
534  * If "name" is specified, the uevent will contain it in
535  * the DEVTYPE variable.
536  */
537 struct device_type {
538 	const char *name;
539 	const struct attribute_group **groups;
540 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
541 	char *(*devnode)(struct device *dev, umode_t *mode,
542 			 kuid_t *uid, kgid_t *gid);
543 	void (*release)(struct device *dev);
544 
545 	const struct dev_pm_ops *pm;
546 };
547 
548 /* interface for exporting device attributes */
549 struct device_attribute {
550 	struct attribute	attr;
551 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
552 			char *buf);
553 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
554 			 const char *buf, size_t count);
555 };
556 
557 struct dev_ext_attribute {
558 	struct device_attribute attr;
559 	void *var;
560 };
561 
562 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
563 			  char *buf);
564 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
565 			   const char *buf, size_t count);
566 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
567 			char *buf);
568 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
569 			 const char *buf, size_t count);
570 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
571 			char *buf);
572 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
573 			 const char *buf, size_t count);
574 
575 #define DEVICE_ATTR(_name, _mode, _show, _store) \
576 	struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
577 #define DEVICE_ATTR_RW(_name) \
578 	struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
579 #define DEVICE_ATTR_RO(_name) \
580 	struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
581 #define DEVICE_ATTR_WO(_name) \
582 	struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
583 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
584 	struct dev_ext_attribute dev_attr_##_name = \
585 		{ __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
586 #define DEVICE_INT_ATTR(_name, _mode, _var) \
587 	struct dev_ext_attribute dev_attr_##_name = \
588 		{ __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
589 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
590 	struct dev_ext_attribute dev_attr_##_name = \
591 		{ __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
592 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
593 	struct device_attribute dev_attr_##_name =		\
594 		__ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
595 
596 extern int device_create_file(struct device *device,
597 			      const struct device_attribute *entry);
598 extern void device_remove_file(struct device *dev,
599 			       const struct device_attribute *attr);
600 extern bool device_remove_file_self(struct device *dev,
601 				    const struct device_attribute *attr);
602 extern int __must_check device_create_bin_file(struct device *dev,
603 					const struct bin_attribute *attr);
604 extern void device_remove_bin_file(struct device *dev,
605 				   const struct bin_attribute *attr);
606 
607 /* device resource management */
608 typedef void (*dr_release_t)(struct device *dev, void *res);
609 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
610 
611 #ifdef CONFIG_DEBUG_DEVRES
612 extern void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
613 				 int nid, const char *name) __malloc;
614 #define devres_alloc(release, size, gfp) \
615 	__devres_alloc_node(release, size, gfp, NUMA_NO_NODE, #release)
616 #define devres_alloc_node(release, size, gfp, nid) \
617 	__devres_alloc_node(release, size, gfp, nid, #release)
618 #else
619 extern void *devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
620 			       int nid) __malloc;
621 static inline void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp)
622 {
623 	return devres_alloc_node(release, size, gfp, NUMA_NO_NODE);
624 }
625 #endif
626 
627 extern void devres_for_each_res(struct device *dev, dr_release_t release,
628 				dr_match_t match, void *match_data,
629 				void (*fn)(struct device *, void *, void *),
630 				void *data);
631 extern void devres_free(void *res);
632 extern void devres_add(struct device *dev, void *res);
633 extern void *devres_find(struct device *dev, dr_release_t release,
634 			 dr_match_t match, void *match_data);
635 extern void *devres_get(struct device *dev, void *new_res,
636 			dr_match_t match, void *match_data);
637 extern void *devres_remove(struct device *dev, dr_release_t release,
638 			   dr_match_t match, void *match_data);
639 extern int devres_destroy(struct device *dev, dr_release_t release,
640 			  dr_match_t match, void *match_data);
641 extern int devres_release(struct device *dev, dr_release_t release,
642 			  dr_match_t match, void *match_data);
643 
644 /* devres group */
645 extern void * __must_check devres_open_group(struct device *dev, void *id,
646 					     gfp_t gfp);
647 extern void devres_close_group(struct device *dev, void *id);
648 extern void devres_remove_group(struct device *dev, void *id);
649 extern int devres_release_group(struct device *dev, void *id);
650 
651 /* managed devm_k.alloc/kfree for device drivers */
652 extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __malloc;
653 extern __printf(3, 0)
654 char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt,
655 		      va_list ap) __malloc;
656 extern __printf(3, 4)
657 char *devm_kasprintf(struct device *dev, gfp_t gfp, const char *fmt, ...) __malloc;
658 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
659 {
660 	return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
661 }
662 static inline void *devm_kmalloc_array(struct device *dev,
663 				       size_t n, size_t size, gfp_t flags)
664 {
665 	if (size != 0 && n > SIZE_MAX / size)
666 		return NULL;
667 	return devm_kmalloc(dev, n * size, flags);
668 }
669 static inline void *devm_kcalloc(struct device *dev,
670 				 size_t n, size_t size, gfp_t flags)
671 {
672 	return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
673 }
674 extern void devm_kfree(struct device *dev, void *p);
675 extern char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
676 extern void *devm_kmemdup(struct device *dev, const void *src, size_t len,
677 			  gfp_t gfp);
678 
679 extern unsigned long devm_get_free_pages(struct device *dev,
680 					 gfp_t gfp_mask, unsigned int order);
681 extern void devm_free_pages(struct device *dev, unsigned long addr);
682 
683 void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
684 
685 /* allows to add/remove a custom action to devres stack */
686 int devm_add_action(struct device *dev, void (*action)(void *), void *data);
687 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
688 
689 static inline int devm_add_action_or_reset(struct device *dev,
690 					   void (*action)(void *), void *data)
691 {
692 	int ret;
693 
694 	ret = devm_add_action(dev, action, data);
695 	if (ret)
696 		action(data);
697 
698 	return ret;
699 }
700 
701 struct device_dma_parameters {
702 	/*
703 	 * a low level driver may set these to teach IOMMU code about
704 	 * sg limitations.
705 	 */
706 	unsigned int max_segment_size;
707 	unsigned long segment_boundary_mask;
708 };
709 
710 /**
711  * struct device - The basic device structure
712  * @parent:	The device's "parent" device, the device to which it is attached.
713  * 		In most cases, a parent device is some sort of bus or host
714  * 		controller. If parent is NULL, the device, is a top-level device,
715  * 		which is not usually what you want.
716  * @p:		Holds the private data of the driver core portions of the device.
717  * 		See the comment of the struct device_private for detail.
718  * @kobj:	A top-level, abstract class from which other classes are derived.
719  * @init_name:	Initial name of the device.
720  * @type:	The type of device.
721  * 		This identifies the device type and carries type-specific
722  * 		information.
723  * @mutex:	Mutex to synchronize calls to its driver.
724  * @bus:	Type of bus device is on.
725  * @driver:	Which driver has allocated this
726  * @platform_data: Platform data specific to the device.
727  * 		Example: For devices on custom boards, as typical of embedded
728  * 		and SOC based hardware, Linux often uses platform_data to point
729  * 		to board-specific structures describing devices and how they
730  * 		are wired.  That can include what ports are available, chip
731  * 		variants, which GPIO pins act in what additional roles, and so
732  * 		on.  This shrinks the "Board Support Packages" (BSPs) and
733  * 		minimizes board-specific #ifdefs in drivers.
734  * @driver_data: Private pointer for driver specific info.
735  * @power:	For device power management.
736  * 		See Documentation/power/devices.txt for details.
737  * @pm_domain:	Provide callbacks that are executed during system suspend,
738  * 		hibernation, system resume and during runtime PM transitions
739  * 		along with subsystem-level and driver-level callbacks.
740  * @pins:	For device pin management.
741  *		See Documentation/pinctrl.txt for details.
742  * @msi_list:	Hosts MSI descriptors
743  * @msi_domain: The generic MSI domain this device is using.
744  * @numa_node:	NUMA node this device is close to.
745  * @dma_mask:	Dma mask (if dma'ble device).
746  * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
747  * 		hardware supports 64-bit addresses for consistent allocations
748  * 		such descriptors.
749  * @dma_pfn_offset: offset of DMA memory range relatively of RAM
750  * @dma_parms:	A low level driver may set these to teach IOMMU code about
751  * 		segment limitations.
752  * @dma_pools:	Dma pools (if dma'ble device).
753  * @dma_mem:	Internal for coherent mem override.
754  * @cma_area:	Contiguous memory area for dma allocations
755  * @archdata:	For arch-specific additions.
756  * @of_node:	Associated device tree node.
757  * @fwnode:	Associated device node supplied by platform firmware.
758  * @devt:	For creating the sysfs "dev".
759  * @id:		device instance
760  * @devres_lock: Spinlock to protect the resource of the device.
761  * @devres_head: The resources list of the device.
762  * @knode_class: The node used to add the device to the class list.
763  * @class:	The class of the device.
764  * @groups:	Optional attribute groups.
765  * @release:	Callback to free the device after all references have
766  * 		gone away. This should be set by the allocator of the
767  * 		device (i.e. the bus driver that discovered the device).
768  * @iommu_group: IOMMU group the device belongs to.
769  * @iommu_fwspec: IOMMU-specific properties supplied by firmware.
770  *
771  * @offline_disabled: If set, the device is permanently online.
772  * @offline:	Set after successful invocation of bus type's .offline().
773  *
774  * At the lowest level, every device in a Linux system is represented by an
775  * instance of struct device. The device structure contains the information
776  * that the device model core needs to model the system. Most subsystems,
777  * however, track additional information about the devices they host. As a
778  * result, it is rare for devices to be represented by bare device structures;
779  * instead, that structure, like kobject structures, is usually embedded within
780  * a higher-level representation of the device.
781  */
782 struct device {
783 	struct device		*parent;
784 
785 	struct device_private	*p;
786 
787 	struct kobject kobj;
788 	const char		*init_name; /* initial name of the device */
789 	const struct device_type *type;
790 
791 	struct mutex		mutex;	/* mutex to synchronize calls to
792 					 * its driver.
793 					 */
794 
795 	struct bus_type	*bus;		/* type of bus device is on */
796 	struct device_driver *driver;	/* which driver has allocated this
797 					   device */
798 	void		*platform_data;	/* Platform specific data, device
799 					   core doesn't touch it */
800 	void		*driver_data;	/* Driver data, set and get with
801 					   dev_set/get_drvdata */
802 	struct dev_pm_info	power;
803 	struct dev_pm_domain	*pm_domain;
804 
805 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
806 	struct irq_domain	*msi_domain;
807 #endif
808 #ifdef CONFIG_PINCTRL
809 	struct dev_pin_info	*pins;
810 #endif
811 #ifdef CONFIG_GENERIC_MSI_IRQ
812 	struct list_head	msi_list;
813 #endif
814 
815 #ifdef CONFIG_NUMA
816 	int		numa_node;	/* NUMA node this device is close to */
817 #endif
818 	u64		*dma_mask;	/* dma mask (if dma'able device) */
819 	u64		coherent_dma_mask;/* Like dma_mask, but for
820 					     alloc_coherent mappings as
821 					     not all hardware supports
822 					     64 bit addresses for consistent
823 					     allocations such descriptors. */
824 	unsigned long	dma_pfn_offset;
825 
826 	struct device_dma_parameters *dma_parms;
827 
828 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
829 
830 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
831 					     override */
832 #ifdef CONFIG_DMA_CMA
833 	struct cma *cma_area;		/* contiguous memory area for dma
834 					   allocations */
835 #endif
836 	/* arch specific additions */
837 	struct dev_archdata	archdata;
838 
839 	struct device_node	*of_node; /* associated device tree node */
840 	struct fwnode_handle	*fwnode; /* firmware device node */
841 
842 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
843 	u32			id;	/* device instance */
844 
845 	spinlock_t		devres_lock;
846 	struct list_head	devres_head;
847 
848 	struct klist_node	knode_class;
849 	struct class		*class;
850 	const struct attribute_group **groups;	/* optional groups */
851 
852 	void	(*release)(struct device *dev);
853 	struct iommu_group	*iommu_group;
854 	struct iommu_fwspec	*iommu_fwspec;
855 
856 	bool			offline_disabled:1;
857 	bool			offline:1;
858 };
859 
860 static inline struct device *kobj_to_dev(struct kobject *kobj)
861 {
862 	return container_of(kobj, struct device, kobj);
863 }
864 
865 /* Get the wakeup routines, which depend on struct device */
866 #include <linux/pm_wakeup.h>
867 
868 static inline const char *dev_name(const struct device *dev)
869 {
870 	/* Use the init name until the kobject becomes available */
871 	if (dev->init_name)
872 		return dev->init_name;
873 
874 	return kobject_name(&dev->kobj);
875 }
876 
877 extern __printf(2, 3)
878 int dev_set_name(struct device *dev, const char *name, ...);
879 
880 #ifdef CONFIG_NUMA
881 static inline int dev_to_node(struct device *dev)
882 {
883 	return dev->numa_node;
884 }
885 static inline void set_dev_node(struct device *dev, int node)
886 {
887 	dev->numa_node = node;
888 }
889 #else
890 static inline int dev_to_node(struct device *dev)
891 {
892 	return -1;
893 }
894 static inline void set_dev_node(struct device *dev, int node)
895 {
896 }
897 #endif
898 
899 static inline struct irq_domain *dev_get_msi_domain(const struct device *dev)
900 {
901 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
902 	return dev->msi_domain;
903 #else
904 	return NULL;
905 #endif
906 }
907 
908 static inline void dev_set_msi_domain(struct device *dev, struct irq_domain *d)
909 {
910 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
911 	dev->msi_domain = d;
912 #endif
913 }
914 
915 static inline void *dev_get_drvdata(const struct device *dev)
916 {
917 	return dev->driver_data;
918 }
919 
920 static inline void dev_set_drvdata(struct device *dev, void *data)
921 {
922 	dev->driver_data = data;
923 }
924 
925 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
926 {
927 	return dev ? dev->power.subsys_data : NULL;
928 }
929 
930 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
931 {
932 	return dev->kobj.uevent_suppress;
933 }
934 
935 static inline void dev_set_uevent_suppress(struct device *dev, int val)
936 {
937 	dev->kobj.uevent_suppress = val;
938 }
939 
940 static inline int device_is_registered(struct device *dev)
941 {
942 	return dev->kobj.state_in_sysfs;
943 }
944 
945 static inline void device_enable_async_suspend(struct device *dev)
946 {
947 	if (!dev->power.is_prepared)
948 		dev->power.async_suspend = true;
949 }
950 
951 static inline void device_disable_async_suspend(struct device *dev)
952 {
953 	if (!dev->power.is_prepared)
954 		dev->power.async_suspend = false;
955 }
956 
957 static inline bool device_async_suspend_enabled(struct device *dev)
958 {
959 	return !!dev->power.async_suspend;
960 }
961 
962 static inline void dev_pm_syscore_device(struct device *dev, bool val)
963 {
964 #ifdef CONFIG_PM_SLEEP
965 	dev->power.syscore = val;
966 #endif
967 }
968 
969 static inline void device_lock(struct device *dev)
970 {
971 	mutex_lock(&dev->mutex);
972 }
973 
974 static inline int device_lock_interruptible(struct device *dev)
975 {
976 	return mutex_lock_interruptible(&dev->mutex);
977 }
978 
979 static inline int device_trylock(struct device *dev)
980 {
981 	return mutex_trylock(&dev->mutex);
982 }
983 
984 static inline void device_unlock(struct device *dev)
985 {
986 	mutex_unlock(&dev->mutex);
987 }
988 
989 static inline void device_lock_assert(struct device *dev)
990 {
991 	lockdep_assert_held(&dev->mutex);
992 }
993 
994 static inline struct device_node *dev_of_node(struct device *dev)
995 {
996 	if (!IS_ENABLED(CONFIG_OF))
997 		return NULL;
998 	return dev->of_node;
999 }
1000 
1001 void driver_init(void);
1002 
1003 /*
1004  * High level routines for use by the bus drivers
1005  */
1006 extern int __must_check device_register(struct device *dev);
1007 extern void device_unregister(struct device *dev);
1008 extern void device_initialize(struct device *dev);
1009 extern int __must_check device_add(struct device *dev);
1010 extern void device_del(struct device *dev);
1011 extern int device_for_each_child(struct device *dev, void *data,
1012 		     int (*fn)(struct device *dev, void *data));
1013 extern int device_for_each_child_reverse(struct device *dev, void *data,
1014 		     int (*fn)(struct device *dev, void *data));
1015 extern struct device *device_find_child(struct device *dev, void *data,
1016 				int (*match)(struct device *dev, void *data));
1017 extern int device_rename(struct device *dev, const char *new_name);
1018 extern int device_move(struct device *dev, struct device *new_parent,
1019 		       enum dpm_order dpm_order);
1020 extern const char *device_get_devnode(struct device *dev,
1021 				      umode_t *mode, kuid_t *uid, kgid_t *gid,
1022 				      const char **tmp);
1023 
1024 static inline bool device_supports_offline(struct device *dev)
1025 {
1026 	return dev->bus && dev->bus->offline && dev->bus->online;
1027 }
1028 
1029 extern void lock_device_hotplug(void);
1030 extern void unlock_device_hotplug(void);
1031 extern int lock_device_hotplug_sysfs(void);
1032 extern int device_offline(struct device *dev);
1033 extern int device_online(struct device *dev);
1034 extern void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1035 extern void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1036 
1037 /*
1038  * Root device objects for grouping under /sys/devices
1039  */
1040 extern struct device *__root_device_register(const char *name,
1041 					     struct module *owner);
1042 
1043 /* This is a macro to avoid include problems with THIS_MODULE */
1044 #define root_device_register(name) \
1045 	__root_device_register(name, THIS_MODULE)
1046 
1047 extern void root_device_unregister(struct device *root);
1048 
1049 static inline void *dev_get_platdata(const struct device *dev)
1050 {
1051 	return dev->platform_data;
1052 }
1053 
1054 /*
1055  * Manual binding of a device to driver. See drivers/base/bus.c
1056  * for information on use.
1057  */
1058 extern int __must_check device_bind_driver(struct device *dev);
1059 extern void device_release_driver(struct device *dev);
1060 extern int  __must_check device_attach(struct device *dev);
1061 extern int __must_check driver_attach(struct device_driver *drv);
1062 extern void device_initial_probe(struct device *dev);
1063 extern int __must_check device_reprobe(struct device *dev);
1064 
1065 extern bool device_is_bound(struct device *dev);
1066 
1067 /*
1068  * Easy functions for dynamically creating devices on the fly
1069  */
1070 extern __printf(5, 0)
1071 struct device *device_create_vargs(struct class *cls, struct device *parent,
1072 				   dev_t devt, void *drvdata,
1073 				   const char *fmt, va_list vargs);
1074 extern __printf(5, 6)
1075 struct device *device_create(struct class *cls, struct device *parent,
1076 			     dev_t devt, void *drvdata,
1077 			     const char *fmt, ...);
1078 extern __printf(6, 7)
1079 struct device *device_create_with_groups(struct class *cls,
1080 			     struct device *parent, dev_t devt, void *drvdata,
1081 			     const struct attribute_group **groups,
1082 			     const char *fmt, ...);
1083 extern void device_destroy(struct class *cls, dev_t devt);
1084 
1085 /*
1086  * Platform "fixup" functions - allow the platform to have their say
1087  * about devices and actions that the general device layer doesn't
1088  * know about.
1089  */
1090 /* Notify platform of device discovery */
1091 extern int (*platform_notify)(struct device *dev);
1092 
1093 extern int (*platform_notify_remove)(struct device *dev);
1094 
1095 
1096 /*
1097  * get_device - atomically increment the reference count for the device.
1098  *
1099  */
1100 extern struct device *get_device(struct device *dev);
1101 extern void put_device(struct device *dev);
1102 
1103 #ifdef CONFIG_DEVTMPFS
1104 extern int devtmpfs_create_node(struct device *dev);
1105 extern int devtmpfs_delete_node(struct device *dev);
1106 extern int devtmpfs_mount(const char *mntdir);
1107 #else
1108 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
1109 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
1110 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
1111 #endif
1112 
1113 /* drivers/base/power/shutdown.c */
1114 extern void device_shutdown(void);
1115 
1116 /* debugging and troubleshooting/diagnostic helpers. */
1117 extern const char *dev_driver_string(const struct device *dev);
1118 
1119 
1120 #ifdef CONFIG_PRINTK
1121 
1122 extern __printf(3, 0)
1123 int dev_vprintk_emit(int level, const struct device *dev,
1124 		     const char *fmt, va_list args);
1125 extern __printf(3, 4)
1126 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...);
1127 
1128 extern __printf(3, 4)
1129 void dev_printk(const char *level, const struct device *dev,
1130 		const char *fmt, ...);
1131 extern __printf(2, 3)
1132 void dev_emerg(const struct device *dev, const char *fmt, ...);
1133 extern __printf(2, 3)
1134 void dev_alert(const struct device *dev, const char *fmt, ...);
1135 extern __printf(2, 3)
1136 void dev_crit(const struct device *dev, const char *fmt, ...);
1137 extern __printf(2, 3)
1138 void dev_err(const struct device *dev, const char *fmt, ...);
1139 extern __printf(2, 3)
1140 void dev_warn(const struct device *dev, const char *fmt, ...);
1141 extern __printf(2, 3)
1142 void dev_notice(const struct device *dev, const char *fmt, ...);
1143 extern __printf(2, 3)
1144 void _dev_info(const struct device *dev, const char *fmt, ...);
1145 
1146 #else
1147 
1148 static inline __printf(3, 0)
1149 int dev_vprintk_emit(int level, const struct device *dev,
1150 		     const char *fmt, va_list args)
1151 { return 0; }
1152 static inline __printf(3, 4)
1153 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
1154 { return 0; }
1155 
1156 static inline void __dev_printk(const char *level, const struct device *dev,
1157 				struct va_format *vaf)
1158 {}
1159 static inline __printf(3, 4)
1160 void dev_printk(const char *level, const struct device *dev,
1161 		const char *fmt, ...)
1162 {}
1163 
1164 static inline __printf(2, 3)
1165 void dev_emerg(const struct device *dev, const char *fmt, ...)
1166 {}
1167 static inline __printf(2, 3)
1168 void dev_crit(const struct device *dev, const char *fmt, ...)
1169 {}
1170 static inline __printf(2, 3)
1171 void dev_alert(const struct device *dev, const char *fmt, ...)
1172 {}
1173 static inline __printf(2, 3)
1174 void dev_err(const struct device *dev, const char *fmt, ...)
1175 {}
1176 static inline __printf(2, 3)
1177 void dev_warn(const struct device *dev, const char *fmt, ...)
1178 {}
1179 static inline __printf(2, 3)
1180 void dev_notice(const struct device *dev, const char *fmt, ...)
1181 {}
1182 static inline __printf(2, 3)
1183 void _dev_info(const struct device *dev, const char *fmt, ...)
1184 {}
1185 
1186 #endif
1187 
1188 /*
1189  * Stupid hackaround for existing uses of non-printk uses dev_info
1190  *
1191  * Note that the definition of dev_info below is actually _dev_info
1192  * and a macro is used to avoid redefining dev_info
1193  */
1194 
1195 #define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)
1196 
1197 #if defined(CONFIG_DYNAMIC_DEBUG)
1198 #define dev_dbg(dev, format, ...)		     \
1199 do {						     \
1200 	dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
1201 } while (0)
1202 #elif defined(DEBUG)
1203 #define dev_dbg(dev, format, arg...)		\
1204 	dev_printk(KERN_DEBUG, dev, format, ##arg)
1205 #else
1206 #define dev_dbg(dev, format, arg...)				\
1207 ({								\
1208 	if (0)							\
1209 		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
1210 })
1211 #endif
1212 
1213 #ifdef CONFIG_PRINTK
1214 #define dev_level_once(dev_level, dev, fmt, ...)			\
1215 do {									\
1216 	static bool __print_once __read_mostly;				\
1217 									\
1218 	if (!__print_once) {						\
1219 		__print_once = true;					\
1220 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1221 	}								\
1222 } while (0)
1223 #else
1224 #define dev_level_once(dev_level, dev, fmt, ...)			\
1225 do {									\
1226 	if (0)								\
1227 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1228 } while (0)
1229 #endif
1230 
1231 #define dev_emerg_once(dev, fmt, ...)					\
1232 	dev_level_once(dev_emerg, dev, fmt, ##__VA_ARGS__)
1233 #define dev_alert_once(dev, fmt, ...)					\
1234 	dev_level_once(dev_alert, dev, fmt, ##__VA_ARGS__)
1235 #define dev_crit_once(dev, fmt, ...)					\
1236 	dev_level_once(dev_crit, dev, fmt, ##__VA_ARGS__)
1237 #define dev_err_once(dev, fmt, ...)					\
1238 	dev_level_once(dev_err, dev, fmt, ##__VA_ARGS__)
1239 #define dev_warn_once(dev, fmt, ...)					\
1240 	dev_level_once(dev_warn, dev, fmt, ##__VA_ARGS__)
1241 #define dev_notice_once(dev, fmt, ...)					\
1242 	dev_level_once(dev_notice, dev, fmt, ##__VA_ARGS__)
1243 #define dev_info_once(dev, fmt, ...)					\
1244 	dev_level_once(dev_info, dev, fmt, ##__VA_ARGS__)
1245 #define dev_dbg_once(dev, fmt, ...)					\
1246 	dev_level_once(dev_dbg, dev, fmt, ##__VA_ARGS__)
1247 
1248 #define dev_level_ratelimited(dev_level, dev, fmt, ...)			\
1249 do {									\
1250 	static DEFINE_RATELIMIT_STATE(_rs,				\
1251 				      DEFAULT_RATELIMIT_INTERVAL,	\
1252 				      DEFAULT_RATELIMIT_BURST);		\
1253 	if (__ratelimit(&_rs))						\
1254 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1255 } while (0)
1256 
1257 #define dev_emerg_ratelimited(dev, fmt, ...)				\
1258 	dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__)
1259 #define dev_alert_ratelimited(dev, fmt, ...)				\
1260 	dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__)
1261 #define dev_crit_ratelimited(dev, fmt, ...)				\
1262 	dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__)
1263 #define dev_err_ratelimited(dev, fmt, ...)				\
1264 	dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__)
1265 #define dev_warn_ratelimited(dev, fmt, ...)				\
1266 	dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__)
1267 #define dev_notice_ratelimited(dev, fmt, ...)				\
1268 	dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__)
1269 #define dev_info_ratelimited(dev, fmt, ...)				\
1270 	dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__)
1271 #if defined(CONFIG_DYNAMIC_DEBUG)
1272 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
1273 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1274 do {									\
1275 	static DEFINE_RATELIMIT_STATE(_rs,				\
1276 				      DEFAULT_RATELIMIT_INTERVAL,	\
1277 				      DEFAULT_RATELIMIT_BURST);		\
1278 	DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);			\
1279 	if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) &&	\
1280 	    __ratelimit(&_rs))						\
1281 		__dynamic_dev_dbg(&descriptor, dev, fmt,		\
1282 				  ##__VA_ARGS__);			\
1283 } while (0)
1284 #elif defined(DEBUG)
1285 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1286 do {									\
1287 	static DEFINE_RATELIMIT_STATE(_rs,				\
1288 				      DEFAULT_RATELIMIT_INTERVAL,	\
1289 				      DEFAULT_RATELIMIT_BURST);		\
1290 	if (__ratelimit(&_rs))						\
1291 		dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__);	\
1292 } while (0)
1293 #else
1294 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1295 do {									\
1296 	if (0)								\
1297 		dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__);	\
1298 } while (0)
1299 #endif
1300 
1301 #ifdef VERBOSE_DEBUG
1302 #define dev_vdbg	dev_dbg
1303 #else
1304 #define dev_vdbg(dev, format, arg...)				\
1305 ({								\
1306 	if (0)							\
1307 		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
1308 })
1309 #endif
1310 
1311 /*
1312  * dev_WARN*() acts like dev_printk(), but with the key difference of
1313  * using WARN/WARN_ONCE to include file/line information and a backtrace.
1314  */
1315 #define dev_WARN(dev, format, arg...) \
1316 	WARN(1, "%s %s: " format, dev_driver_string(dev), dev_name(dev), ## arg);
1317 
1318 #define dev_WARN_ONCE(dev, condition, format, arg...) \
1319 	WARN_ONCE(condition, "%s %s: " format, \
1320 			dev_driver_string(dev), dev_name(dev), ## arg)
1321 
1322 /* Create alias, so I can be autoloaded. */
1323 #define MODULE_ALIAS_CHARDEV(major,minor) \
1324 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1325 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1326 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
1327 
1328 #ifdef CONFIG_SYSFS_DEPRECATED
1329 extern long sysfs_deprecated;
1330 #else
1331 #define sysfs_deprecated 0
1332 #endif
1333 
1334 /**
1335  * module_driver() - Helper macro for drivers that don't do anything
1336  * special in module init/exit. This eliminates a lot of boilerplate.
1337  * Each module may only use this macro once, and calling it replaces
1338  * module_init() and module_exit().
1339  *
1340  * @__driver: driver name
1341  * @__register: register function for this driver type
1342  * @__unregister: unregister function for this driver type
1343  * @...: Additional arguments to be passed to __register and __unregister.
1344  *
1345  * Use this macro to construct bus specific macros for registering
1346  * drivers, and do not use it on its own.
1347  */
1348 #define module_driver(__driver, __register, __unregister, ...) \
1349 static int __init __driver##_init(void) \
1350 { \
1351 	return __register(&(__driver) , ##__VA_ARGS__); \
1352 } \
1353 module_init(__driver##_init); \
1354 static void __exit __driver##_exit(void) \
1355 { \
1356 	__unregister(&(__driver) , ##__VA_ARGS__); \
1357 } \
1358 module_exit(__driver##_exit);
1359 
1360 /**
1361  * builtin_driver() - Helper macro for drivers that don't do anything
1362  * special in init and have no exit. This eliminates some boilerplate.
1363  * Each driver may only use this macro once, and calling it replaces
1364  * device_initcall (or in some cases, the legacy __initcall).  This is
1365  * meant to be a direct parallel of module_driver() above but without
1366  * the __exit stuff that is not used for builtin cases.
1367  *
1368  * @__driver: driver name
1369  * @__register: register function for this driver type
1370  * @...: Additional arguments to be passed to __register
1371  *
1372  * Use this macro to construct bus specific macros for registering
1373  * drivers, and do not use it on its own.
1374  */
1375 #define builtin_driver(__driver, __register, ...) \
1376 static int __init __driver##_init(void) \
1377 { \
1378 	return __register(&(__driver) , ##__VA_ARGS__); \
1379 } \
1380 device_initcall(__driver##_init);
1381 
1382 #endif /* _DEVICE_H_ */
1383