xref: /linux-6.15/include/linux/device.h (revision 6ae0a628)
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  * @num_vf:	Called to find out how many virtual functions a device on this
92  *		bus supports.
93  * @pm:		Power management operations of this bus, callback the specific
94  *		device driver's pm-ops.
95  * @iommu_ops:  IOMMU specific operations for this bus, used to attach IOMMU
96  *              driver implementations to a bus and allow the driver to do
97  *              bus-specific setup
98  * @p:		The private data of the driver core, only the driver core can
99  *		touch this.
100  * @lock_key:	Lock class key for use by the lock validator
101  *
102  * A bus is a channel between the processor and one or more devices. For the
103  * purposes of the device model, all devices are connected via a bus, even if
104  * it is an internal, virtual, "platform" bus. Buses can plug into each other.
105  * A USB controller is usually a PCI device, for example. The device model
106  * represents the actual connections between buses and the devices they control.
107  * A bus is represented by the bus_type structure. It contains the name, the
108  * default attributes, the bus' methods, PM operations, and the driver core's
109  * private data.
110  */
111 struct bus_type {
112 	const char		*name;
113 	const char		*dev_name;
114 	struct device		*dev_root;
115 	struct device_attribute	*dev_attrs;	/* use dev_groups instead */
116 	const struct attribute_group **bus_groups;
117 	const struct attribute_group **dev_groups;
118 	const struct attribute_group **drv_groups;
119 
120 	int (*match)(struct device *dev, struct device_driver *drv);
121 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
122 	int (*probe)(struct device *dev);
123 	int (*remove)(struct device *dev);
124 	void (*shutdown)(struct device *dev);
125 
126 	int (*online)(struct device *dev);
127 	int (*offline)(struct device *dev);
128 
129 	int (*suspend)(struct device *dev, pm_message_t state);
130 	int (*resume)(struct device *dev);
131 
132 	int (*num_vf)(struct device *dev);
133 
134 	const struct dev_pm_ops *pm;
135 
136 	const struct iommu_ops *iommu_ops;
137 
138 	struct subsys_private *p;
139 	struct lock_class_key lock_key;
140 };
141 
142 extern int __must_check bus_register(struct bus_type *bus);
143 
144 extern void bus_unregister(struct bus_type *bus);
145 
146 extern int __must_check bus_rescan_devices(struct bus_type *bus);
147 
148 /* iterator helpers for buses */
149 struct subsys_dev_iter {
150 	struct klist_iter		ki;
151 	const struct device_type	*type;
152 };
153 void subsys_dev_iter_init(struct subsys_dev_iter *iter,
154 			 struct bus_type *subsys,
155 			 struct device *start,
156 			 const struct device_type *type);
157 struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter);
158 void subsys_dev_iter_exit(struct subsys_dev_iter *iter);
159 
160 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
161 		     int (*fn)(struct device *dev, void *data));
162 struct device *bus_find_device(struct bus_type *bus, struct device *start,
163 			       void *data,
164 			       int (*match)(struct device *dev, void *data));
165 struct device *bus_find_device_by_name(struct bus_type *bus,
166 				       struct device *start,
167 				       const char *name);
168 struct device *subsys_find_device_by_id(struct bus_type *bus, unsigned int id,
169 					struct device *hint);
170 int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
171 		     void *data, int (*fn)(struct device_driver *, void *));
172 void bus_sort_breadthfirst(struct bus_type *bus,
173 			   int (*compare)(const struct device *a,
174 					  const struct device *b));
175 /*
176  * Bus notifiers: Get notified of addition/removal of devices
177  * and binding/unbinding of drivers to devices.
178  * In the long run, it should be a replacement for the platform
179  * notify hooks.
180  */
181 struct notifier_block;
182 
183 extern int bus_register_notifier(struct bus_type *bus,
184 				 struct notifier_block *nb);
185 extern int bus_unregister_notifier(struct bus_type *bus,
186 				   struct notifier_block *nb);
187 
188 /* All 4 notifers below get called with the target struct device *
189  * as an argument. Note that those functions are likely to be called
190  * with the device lock held in the core, so be careful.
191  */
192 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
193 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device to be removed */
194 #define BUS_NOTIFY_REMOVED_DEVICE	0x00000003 /* device removed */
195 #define BUS_NOTIFY_BIND_DRIVER		0x00000004 /* driver about to be
196 						      bound */
197 #define BUS_NOTIFY_BOUND_DRIVER		0x00000005 /* driver bound to device */
198 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000006 /* driver about to be
199 						      unbound */
200 #define BUS_NOTIFY_UNBOUND_DRIVER	0x00000007 /* driver is unbound
201 						      from the device */
202 #define BUS_NOTIFY_DRIVER_NOT_BOUND	0x00000008 /* driver fails to be bound */
203 
204 extern struct kset *bus_get_kset(struct bus_type *bus);
205 extern struct klist *bus_get_device_klist(struct bus_type *bus);
206 
207 /**
208  * enum probe_type - device driver probe type to try
209  *	Device drivers may opt in for special handling of their
210  *	respective probe routines. This tells the core what to
211  *	expect and prefer.
212  *
213  * @PROBE_DEFAULT_STRATEGY: Used by drivers that work equally well
214  *	whether probed synchronously or asynchronously.
215  * @PROBE_PREFER_ASYNCHRONOUS: Drivers for "slow" devices which
216  *	probing order is not essential for booting the system may
217  *	opt into executing their probes asynchronously.
218  * @PROBE_FORCE_SYNCHRONOUS: Use this to annotate drivers that need
219  *	their probe routines to run synchronously with driver and
220  *	device registration (with the exception of -EPROBE_DEFER
221  *	handling - re-probing always ends up being done asynchronously).
222  *
223  * Note that the end goal is to switch the kernel to use asynchronous
224  * probing by default, so annotating drivers with
225  * %PROBE_PREFER_ASYNCHRONOUS is a temporary measure that allows us
226  * to speed up boot process while we are validating the rest of the
227  * drivers.
228  */
229 enum probe_type {
230 	PROBE_DEFAULT_STRATEGY,
231 	PROBE_PREFER_ASYNCHRONOUS,
232 	PROBE_FORCE_SYNCHRONOUS,
233 };
234 
235 /**
236  * struct device_driver - The basic device driver structure
237  * @name:	Name of the device driver.
238  * @bus:	The bus which the device of this driver belongs to.
239  * @owner:	The module owner.
240  * @mod_name:	Used for built-in modules.
241  * @suppress_bind_attrs: Disables bind/unbind via sysfs.
242  * @probe_type:	Type of the probe (synchronous or asynchronous) to use.
243  * @of_match_table: The open firmware table.
244  * @acpi_match_table: The ACPI match table.
245  * @probe:	Called to query the existence of a specific device,
246  *		whether this driver can work with it, and bind the driver
247  *		to a specific device.
248  * @remove:	Called when the device is removed from the system to
249  *		unbind a device from this driver.
250  * @shutdown:	Called at shut-down time to quiesce the device.
251  * @suspend:	Called to put the device to sleep mode. Usually to a
252  *		low power state.
253  * @resume:	Called to bring a device from sleep mode.
254  * @groups:	Default attributes that get created by the driver core
255  *		automatically.
256  * @pm:		Power management operations of the device which matched
257  *		this driver.
258  * @p:		Driver core's private data, no one other than the driver
259  *		core can touch this.
260  *
261  * The device driver-model tracks all of the drivers known to the system.
262  * The main reason for this tracking is to enable the driver core to match
263  * up drivers with new devices. Once drivers are known objects within the
264  * system, however, a number of other things become possible. Device drivers
265  * can export information and configuration variables that are independent
266  * of any specific device.
267  */
268 struct device_driver {
269 	const char		*name;
270 	struct bus_type		*bus;
271 
272 	struct module		*owner;
273 	const char		*mod_name;	/* used for built-in modules */
274 
275 	bool suppress_bind_attrs;	/* disables bind/unbind via sysfs */
276 	enum probe_type probe_type;
277 
278 	const struct of_device_id	*of_match_table;
279 	const struct acpi_device_id	*acpi_match_table;
280 
281 	int (*probe) (struct device *dev);
282 	int (*remove) (struct device *dev);
283 	void (*shutdown) (struct device *dev);
284 	int (*suspend) (struct device *dev, pm_message_t state);
285 	int (*resume) (struct device *dev);
286 	const struct attribute_group **groups;
287 
288 	const struct dev_pm_ops *pm;
289 
290 	struct driver_private *p;
291 };
292 
293 
294 extern int __must_check driver_register(struct device_driver *drv);
295 extern void driver_unregister(struct device_driver *drv);
296 
297 extern struct device_driver *driver_find(const char *name,
298 					 struct bus_type *bus);
299 extern int driver_probe_done(void);
300 extern void wait_for_device_probe(void);
301 
302 
303 /* sysfs interface for exporting driver attributes */
304 
305 struct driver_attribute {
306 	struct attribute attr;
307 	ssize_t (*show)(struct device_driver *driver, char *buf);
308 	ssize_t (*store)(struct device_driver *driver, const char *buf,
309 			 size_t count);
310 };
311 
312 #define DRIVER_ATTR(_name, _mode, _show, _store) \
313 	struct driver_attribute driver_attr_##_name = __ATTR(_name, _mode, _show, _store)
314 #define DRIVER_ATTR_RW(_name) \
315 	struct driver_attribute driver_attr_##_name = __ATTR_RW(_name)
316 #define DRIVER_ATTR_RO(_name) \
317 	struct driver_attribute driver_attr_##_name = __ATTR_RO(_name)
318 #define DRIVER_ATTR_WO(_name) \
319 	struct driver_attribute driver_attr_##_name = __ATTR_WO(_name)
320 
321 extern int __must_check driver_create_file(struct device_driver *driver,
322 					const struct driver_attribute *attr);
323 extern void driver_remove_file(struct device_driver *driver,
324 			       const struct driver_attribute *attr);
325 
326 extern int __must_check driver_for_each_device(struct device_driver *drv,
327 					       struct device *start,
328 					       void *data,
329 					       int (*fn)(struct device *dev,
330 							 void *));
331 struct device *driver_find_device(struct device_driver *drv,
332 				  struct device *start, void *data,
333 				  int (*match)(struct device *dev, void *data));
334 
335 /**
336  * struct subsys_interface - interfaces to device functions
337  * @name:       name of the device function
338  * @subsys:     subsytem of the devices to attach to
339  * @node:       the list of functions registered at the subsystem
340  * @add_dev:    device hookup to device function handler
341  * @remove_dev: device hookup to device function handler
342  *
343  * Simple interfaces attached to a subsystem. Multiple interfaces can
344  * attach to a subsystem and its devices. Unlike drivers, they do not
345  * exclusively claim or control devices. Interfaces usually represent
346  * a specific functionality of a subsystem/class of devices.
347  */
348 struct subsys_interface {
349 	const char *name;
350 	struct bus_type *subsys;
351 	struct list_head node;
352 	int (*add_dev)(struct device *dev, struct subsys_interface *sif);
353 	void (*remove_dev)(struct device *dev, struct subsys_interface *sif);
354 };
355 
356 int subsys_interface_register(struct subsys_interface *sif);
357 void subsys_interface_unregister(struct subsys_interface *sif);
358 
359 int subsys_system_register(struct bus_type *subsys,
360 			   const struct attribute_group **groups);
361 int subsys_virtual_register(struct bus_type *subsys,
362 			    const struct attribute_group **groups);
363 
364 /**
365  * struct class - device classes
366  * @name:	Name of the class.
367  * @owner:	The module owner.
368  * @class_attrs: Default attributes of this class.
369  * @class_groups: Default attributes of this class.
370  * @dev_groups:	Default attributes of the devices that belong to the class.
371  * @dev_kobj:	The kobject that represents this class and links it into the hierarchy.
372  * @dev_uevent:	Called when a device is added, removed from this class, or a
373  *		few other things that generate uevents to add the environment
374  *		variables.
375  * @devnode:	Callback to provide the devtmpfs.
376  * @class_release: Called to release this class.
377  * @dev_release: Called to release the device.
378  * @suspend:	Used to put the device to sleep mode, usually to a low power
379  *		state.
380  * @resume:	Used to bring the device from the sleep mode.
381  * @ns_type:	Callbacks so sysfs can detemine namespaces.
382  * @namespace:	Namespace of the device belongs to this class.
383  * @pm:		The default device power management operations of this class.
384  * @p:		The private data of the driver core, no one other than the
385  *		driver core can touch this.
386  *
387  * A class is a higher-level view of a device that abstracts out low-level
388  * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
389  * at the class level, they are all simply disks. Classes allow user space
390  * to work with devices based on what they do, rather than how they are
391  * connected or how they work.
392  */
393 struct class {
394 	const char		*name;
395 	struct module		*owner;
396 
397 	struct class_attribute		*class_attrs;
398 	const struct attribute_group	**class_groups;
399 	const struct attribute_group	**dev_groups;
400 	struct kobject			*dev_kobj;
401 
402 	int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
403 	char *(*devnode)(struct device *dev, umode_t *mode);
404 
405 	void (*class_release)(struct class *class);
406 	void (*dev_release)(struct device *dev);
407 
408 	int (*suspend)(struct device *dev, pm_message_t state);
409 	int (*resume)(struct device *dev);
410 
411 	const struct kobj_ns_type_operations *ns_type;
412 	const void *(*namespace)(struct device *dev);
413 
414 	const struct dev_pm_ops *pm;
415 
416 	struct subsys_private *p;
417 };
418 
419 struct class_dev_iter {
420 	struct klist_iter		ki;
421 	const struct device_type	*type;
422 };
423 
424 extern struct kobject *sysfs_dev_block_kobj;
425 extern struct kobject *sysfs_dev_char_kobj;
426 extern int __must_check __class_register(struct class *class,
427 					 struct lock_class_key *key);
428 extern void class_unregister(struct class *class);
429 
430 /* This is a #define to keep the compiler from merging different
431  * instances of the __key variable */
432 #define class_register(class)			\
433 ({						\
434 	static struct lock_class_key __key;	\
435 	__class_register(class, &__key);	\
436 })
437 
438 struct class_compat;
439 struct class_compat *class_compat_register(const char *name);
440 void class_compat_unregister(struct class_compat *cls);
441 int class_compat_create_link(struct class_compat *cls, struct device *dev,
442 			     struct device *device_link);
443 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
444 			      struct device *device_link);
445 
446 extern void class_dev_iter_init(struct class_dev_iter *iter,
447 				struct class *class,
448 				struct device *start,
449 				const struct device_type *type);
450 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
451 extern void class_dev_iter_exit(struct class_dev_iter *iter);
452 
453 extern int class_for_each_device(struct class *class, struct device *start,
454 				 void *data,
455 				 int (*fn)(struct device *dev, void *data));
456 extern struct device *class_find_device(struct class *class,
457 					struct device *start, const void *data,
458 					int (*match)(struct device *, const void *));
459 
460 struct class_attribute {
461 	struct attribute attr;
462 	ssize_t (*show)(struct class *class, struct class_attribute *attr,
463 			char *buf);
464 	ssize_t (*store)(struct class *class, struct class_attribute *attr,
465 			const char *buf, size_t count);
466 };
467 
468 #define CLASS_ATTR(_name, _mode, _show, _store) \
469 	struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)
470 #define CLASS_ATTR_RW(_name) \
471 	struct class_attribute class_attr_##_name = __ATTR_RW(_name)
472 #define CLASS_ATTR_RO(_name) \
473 	struct class_attribute class_attr_##_name = __ATTR_RO(_name)
474 #define CLASS_ATTR_WO(_name) \
475 	struct class_attribute class_attr_##_name = __ATTR_WO(_name)
476 
477 extern int __must_check class_create_file_ns(struct class *class,
478 					     const struct class_attribute *attr,
479 					     const void *ns);
480 extern void class_remove_file_ns(struct class *class,
481 				 const struct class_attribute *attr,
482 				 const void *ns);
483 
484 static inline int __must_check class_create_file(struct class *class,
485 					const struct class_attribute *attr)
486 {
487 	return class_create_file_ns(class, attr, NULL);
488 }
489 
490 static inline void class_remove_file(struct class *class,
491 				     const struct class_attribute *attr)
492 {
493 	return class_remove_file_ns(class, attr, NULL);
494 }
495 
496 /* Simple class attribute that is just a static string */
497 struct class_attribute_string {
498 	struct class_attribute attr;
499 	char *str;
500 };
501 
502 /* Currently read-only only */
503 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
504 	{ __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
505 #define CLASS_ATTR_STRING(_name, _mode, _str) \
506 	struct class_attribute_string class_attr_##_name = \
507 		_CLASS_ATTR_STRING(_name, _mode, _str)
508 
509 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
510                         char *buf);
511 
512 struct class_interface {
513 	struct list_head	node;
514 	struct class		*class;
515 
516 	int (*add_dev)		(struct device *, struct class_interface *);
517 	void (*remove_dev)	(struct device *, struct class_interface *);
518 };
519 
520 extern int __must_check class_interface_register(struct class_interface *);
521 extern void class_interface_unregister(struct class_interface *);
522 
523 extern struct class * __must_check __class_create(struct module *owner,
524 						  const char *name,
525 						  struct lock_class_key *key);
526 extern void class_destroy(struct class *cls);
527 
528 /* This is a #define to keep the compiler from merging different
529  * instances of the __key variable */
530 #define class_create(owner, name)		\
531 ({						\
532 	static struct lock_class_key __key;	\
533 	__class_create(owner, name, &__key);	\
534 })
535 
536 /*
537  * The type of device, "struct device" is embedded in. A class
538  * or bus can contain devices of different types
539  * like "partitions" and "disks", "mouse" and "event".
540  * This identifies the device type and carries type-specific
541  * information, equivalent to the kobj_type of a kobject.
542  * If "name" is specified, the uevent will contain it in
543  * the DEVTYPE variable.
544  */
545 struct device_type {
546 	const char *name;
547 	const struct attribute_group **groups;
548 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
549 	char *(*devnode)(struct device *dev, umode_t *mode,
550 			 kuid_t *uid, kgid_t *gid);
551 	void (*release)(struct device *dev);
552 
553 	const struct dev_pm_ops *pm;
554 };
555 
556 /* interface for exporting device attributes */
557 struct device_attribute {
558 	struct attribute	attr;
559 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
560 			char *buf);
561 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
562 			 const char *buf, size_t count);
563 };
564 
565 struct dev_ext_attribute {
566 	struct device_attribute attr;
567 	void *var;
568 };
569 
570 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
571 			  char *buf);
572 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
573 			   const char *buf, size_t count);
574 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
575 			char *buf);
576 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
577 			 const char *buf, size_t count);
578 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
579 			char *buf);
580 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
581 			 const char *buf, size_t count);
582 
583 #define DEVICE_ATTR(_name, _mode, _show, _store) \
584 	struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
585 #define DEVICE_ATTR_RW(_name) \
586 	struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
587 #define DEVICE_ATTR_RO(_name) \
588 	struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
589 #define DEVICE_ATTR_WO(_name) \
590 	struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
591 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
592 	struct dev_ext_attribute dev_attr_##_name = \
593 		{ __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
594 #define DEVICE_INT_ATTR(_name, _mode, _var) \
595 	struct dev_ext_attribute dev_attr_##_name = \
596 		{ __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
597 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
598 	struct dev_ext_attribute dev_attr_##_name = \
599 		{ __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
600 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
601 	struct device_attribute dev_attr_##_name =		\
602 		__ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
603 
604 extern int device_create_file(struct device *device,
605 			      const struct device_attribute *entry);
606 extern void device_remove_file(struct device *dev,
607 			       const struct device_attribute *attr);
608 extern bool device_remove_file_self(struct device *dev,
609 				    const struct device_attribute *attr);
610 extern int __must_check device_create_bin_file(struct device *dev,
611 					const struct bin_attribute *attr);
612 extern void device_remove_bin_file(struct device *dev,
613 				   const struct bin_attribute *attr);
614 
615 /* device resource management */
616 typedef void (*dr_release_t)(struct device *dev, void *res);
617 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
618 
619 #ifdef CONFIG_DEBUG_DEVRES
620 extern void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
621 				 int nid, const char *name) __malloc;
622 #define devres_alloc(release, size, gfp) \
623 	__devres_alloc_node(release, size, gfp, NUMA_NO_NODE, #release)
624 #define devres_alloc_node(release, size, gfp, nid) \
625 	__devres_alloc_node(release, size, gfp, nid, #release)
626 #else
627 extern void *devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
628 			       int nid) __malloc;
629 static inline void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp)
630 {
631 	return devres_alloc_node(release, size, gfp, NUMA_NO_NODE);
632 }
633 #endif
634 
635 extern void devres_for_each_res(struct device *dev, dr_release_t release,
636 				dr_match_t match, void *match_data,
637 				void (*fn)(struct device *, void *, void *),
638 				void *data);
639 extern void devres_free(void *res);
640 extern void devres_add(struct device *dev, void *res);
641 extern void *devres_find(struct device *dev, dr_release_t release,
642 			 dr_match_t match, void *match_data);
643 extern void *devres_get(struct device *dev, void *new_res,
644 			dr_match_t match, void *match_data);
645 extern void *devres_remove(struct device *dev, dr_release_t release,
646 			   dr_match_t match, void *match_data);
647 extern int devres_destroy(struct device *dev, dr_release_t release,
648 			  dr_match_t match, void *match_data);
649 extern int devres_release(struct device *dev, dr_release_t release,
650 			  dr_match_t match, void *match_data);
651 
652 /* devres group */
653 extern void * __must_check devres_open_group(struct device *dev, void *id,
654 					     gfp_t gfp);
655 extern void devres_close_group(struct device *dev, void *id);
656 extern void devres_remove_group(struct device *dev, void *id);
657 extern int devres_release_group(struct device *dev, void *id);
658 
659 /* managed devm_k.alloc/kfree for device drivers */
660 extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __malloc;
661 extern __printf(3, 0)
662 char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt,
663 		      va_list ap) __malloc;
664 extern __printf(3, 4)
665 char *devm_kasprintf(struct device *dev, gfp_t gfp, const char *fmt, ...) __malloc;
666 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
667 {
668 	return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
669 }
670 static inline void *devm_kmalloc_array(struct device *dev,
671 				       size_t n, size_t size, gfp_t flags)
672 {
673 	if (size != 0 && n > SIZE_MAX / size)
674 		return NULL;
675 	return devm_kmalloc(dev, n * size, flags);
676 }
677 static inline void *devm_kcalloc(struct device *dev,
678 				 size_t n, size_t size, gfp_t flags)
679 {
680 	return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
681 }
682 extern void devm_kfree(struct device *dev, void *p);
683 extern char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
684 extern void *devm_kmemdup(struct device *dev, const void *src, size_t len,
685 			  gfp_t gfp);
686 
687 extern unsigned long devm_get_free_pages(struct device *dev,
688 					 gfp_t gfp_mask, unsigned int order);
689 extern void devm_free_pages(struct device *dev, unsigned long addr);
690 
691 void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
692 
693 /* allows to add/remove a custom action to devres stack */
694 int devm_add_action(struct device *dev, void (*action)(void *), void *data);
695 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
696 
697 static inline int devm_add_action_or_reset(struct device *dev,
698 					   void (*action)(void *), void *data)
699 {
700 	int ret;
701 
702 	ret = devm_add_action(dev, action, data);
703 	if (ret)
704 		action(data);
705 
706 	return ret;
707 }
708 
709 /**
710  * devm_alloc_percpu - Resource-managed alloc_percpu
711  * @dev: Device to allocate per-cpu memory for
712  * @type: Type to allocate per-cpu memory for
713  *
714  * Managed alloc_percpu. Per-cpu memory allocated with this function is
715  * automatically freed on driver detach.
716  *
717  * RETURNS:
718  * Pointer to allocated memory on success, NULL on failure.
719  */
720 #define devm_alloc_percpu(dev, type)      \
721 	((typeof(type) __percpu *)__devm_alloc_percpu((dev), sizeof(type), \
722 						      __alignof__(type)))
723 
724 void __percpu *__devm_alloc_percpu(struct device *dev, size_t size,
725 				   size_t align);
726 void devm_free_percpu(struct device *dev, void __percpu *pdata);
727 
728 struct device_dma_parameters {
729 	/*
730 	 * a low level driver may set these to teach IOMMU code about
731 	 * sg limitations.
732 	 */
733 	unsigned int max_segment_size;
734 	unsigned long segment_boundary_mask;
735 };
736 
737 /**
738  * enum device_link_state - Device link states.
739  * @DL_STATE_NONE: The presence of the drivers is not being tracked.
740  * @DL_STATE_DORMANT: None of the supplier/consumer drivers is present.
741  * @DL_STATE_AVAILABLE: The supplier driver is present, but the consumer is not.
742  * @DL_STATE_CONSUMER_PROBE: The consumer is probing (supplier driver present).
743  * @DL_STATE_ACTIVE: Both the supplier and consumer drivers are present.
744  * @DL_STATE_SUPPLIER_UNBIND: The supplier driver is unbinding.
745  */
746 enum device_link_state {
747 	DL_STATE_NONE = -1,
748 	DL_STATE_DORMANT = 0,
749 	DL_STATE_AVAILABLE,
750 	DL_STATE_CONSUMER_PROBE,
751 	DL_STATE_ACTIVE,
752 	DL_STATE_SUPPLIER_UNBIND,
753 };
754 
755 /*
756  * Device link flags.
757  *
758  * STATELESS: The core won't track the presence of supplier/consumer drivers.
759  * AUTOREMOVE: Remove this link automatically on consumer driver unbind.
760  * PM_RUNTIME: If set, the runtime PM framework will use this link.
761  * RPM_ACTIVE: Run pm_runtime_get_sync() on the supplier during link creation.
762  */
763 #define DL_FLAG_STATELESS	BIT(0)
764 #define DL_FLAG_AUTOREMOVE	BIT(1)
765 #define DL_FLAG_PM_RUNTIME	BIT(2)
766 #define DL_FLAG_RPM_ACTIVE	BIT(3)
767 
768 /**
769  * struct device_link - Device link representation.
770  * @supplier: The device on the supplier end of the link.
771  * @s_node: Hook to the supplier device's list of links to consumers.
772  * @consumer: The device on the consumer end of the link.
773  * @c_node: Hook to the consumer device's list of links to suppliers.
774  * @status: The state of the link (with respect to the presence of drivers).
775  * @flags: Link flags.
776  * @rpm_active: Whether or not the consumer device is runtime-PM-active.
777  * @rcu_head: An RCU head to use for deferred execution of SRCU callbacks.
778  */
779 struct device_link {
780 	struct device *supplier;
781 	struct list_head s_node;
782 	struct device *consumer;
783 	struct list_head c_node;
784 	enum device_link_state status;
785 	u32 flags;
786 	bool rpm_active;
787 #ifdef CONFIG_SRCU
788 	struct rcu_head rcu_head;
789 #endif
790 };
791 
792 /**
793  * enum dl_dev_state - Device driver presence tracking information.
794  * @DL_DEV_NO_DRIVER: There is no driver attached to the device.
795  * @DL_DEV_PROBING: A driver is probing.
796  * @DL_DEV_DRIVER_BOUND: The driver has been bound to the device.
797  * @DL_DEV_UNBINDING: The driver is unbinding from the device.
798  */
799 enum dl_dev_state {
800 	DL_DEV_NO_DRIVER = 0,
801 	DL_DEV_PROBING,
802 	DL_DEV_DRIVER_BOUND,
803 	DL_DEV_UNBINDING,
804 };
805 
806 /**
807  * struct dev_links_info - Device data related to device links.
808  * @suppliers: List of links to supplier devices.
809  * @consumers: List of links to consumer devices.
810  * @status: Driver status information.
811  */
812 struct dev_links_info {
813 	struct list_head suppliers;
814 	struct list_head consumers;
815 	enum dl_dev_state status;
816 };
817 
818 /**
819  * struct device - The basic device structure
820  * @parent:	The device's "parent" device, the device to which it is attached.
821  * 		In most cases, a parent device is some sort of bus or host
822  * 		controller. If parent is NULL, the device, is a top-level device,
823  * 		which is not usually what you want.
824  * @p:		Holds the private data of the driver core portions of the device.
825  * 		See the comment of the struct device_private for detail.
826  * @kobj:	A top-level, abstract class from which other classes are derived.
827  * @init_name:	Initial name of the device.
828  * @type:	The type of device.
829  * 		This identifies the device type and carries type-specific
830  * 		information.
831  * @mutex:	Mutex to synchronize calls to its driver.
832  * @bus:	Type of bus device is on.
833  * @driver:	Which driver has allocated this
834  * @platform_data: Platform data specific to the device.
835  * 		Example: For devices on custom boards, as typical of embedded
836  * 		and SOC based hardware, Linux often uses platform_data to point
837  * 		to board-specific structures describing devices and how they
838  * 		are wired.  That can include what ports are available, chip
839  * 		variants, which GPIO pins act in what additional roles, and so
840  * 		on.  This shrinks the "Board Support Packages" (BSPs) and
841  * 		minimizes board-specific #ifdefs in drivers.
842  * @driver_data: Private pointer for driver specific info.
843  * @links:	Links to suppliers and consumers of this device.
844  * @power:	For device power management.
845  * 		See Documentation/power/admin-guide/devices.rst for details.
846  * @pm_domain:	Provide callbacks that are executed during system suspend,
847  * 		hibernation, system resume and during runtime PM transitions
848  * 		along with subsystem-level and driver-level callbacks.
849  * @pins:	For device pin management.
850  *		See Documentation/pinctrl.txt for details.
851  * @msi_list:	Hosts MSI descriptors
852  * @msi_domain: The generic MSI domain this device is using.
853  * @numa_node:	NUMA node this device is close to.
854  * @dma_mask:	Dma mask (if dma'ble device).
855  * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
856  * 		hardware supports 64-bit addresses for consistent allocations
857  * 		such descriptors.
858  * @dma_pfn_offset: offset of DMA memory range relatively of RAM
859  * @dma_parms:	A low level driver may set these to teach IOMMU code about
860  * 		segment limitations.
861  * @dma_pools:	Dma pools (if dma'ble device).
862  * @dma_mem:	Internal for coherent mem override.
863  * @cma_area:	Contiguous memory area for dma allocations
864  * @archdata:	For arch-specific additions.
865  * @of_node:	Associated device tree node.
866  * @fwnode:	Associated device node supplied by platform firmware.
867  * @devt:	For creating the sysfs "dev".
868  * @id:		device instance
869  * @devres_lock: Spinlock to protect the resource of the device.
870  * @devres_head: The resources list of the device.
871  * @knode_class: The node used to add the device to the class list.
872  * @class:	The class of the device.
873  * @groups:	Optional attribute groups.
874  * @release:	Callback to free the device after all references have
875  * 		gone away. This should be set by the allocator of the
876  * 		device (i.e. the bus driver that discovered the device).
877  * @iommu_group: IOMMU group the device belongs to.
878  * @iommu_fwspec: IOMMU-specific properties supplied by firmware.
879  *
880  * @offline_disabled: If set, the device is permanently online.
881  * @offline:	Set after successful invocation of bus type's .offline().
882  *
883  * At the lowest level, every device in a Linux system is represented by an
884  * instance of struct device. The device structure contains the information
885  * that the device model core needs to model the system. Most subsystems,
886  * however, track additional information about the devices they host. As a
887  * result, it is rare for devices to be represented by bare device structures;
888  * instead, that structure, like kobject structures, is usually embedded within
889  * a higher-level representation of the device.
890  */
891 struct device {
892 	struct device		*parent;
893 
894 	struct device_private	*p;
895 
896 	struct kobject kobj;
897 	const char		*init_name; /* initial name of the device */
898 	const struct device_type *type;
899 
900 	struct mutex		mutex;	/* mutex to synchronize calls to
901 					 * its driver.
902 					 */
903 
904 	struct bus_type	*bus;		/* type of bus device is on */
905 	struct device_driver *driver;	/* which driver has allocated this
906 					   device */
907 	void		*platform_data;	/* Platform specific data, device
908 					   core doesn't touch it */
909 	void		*driver_data;	/* Driver data, set and get with
910 					   dev_set/get_drvdata */
911 	struct dev_links_info	links;
912 	struct dev_pm_info	power;
913 	struct dev_pm_domain	*pm_domain;
914 
915 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
916 	struct irq_domain	*msi_domain;
917 #endif
918 #ifdef CONFIG_PINCTRL
919 	struct dev_pin_info	*pins;
920 #endif
921 #ifdef CONFIG_GENERIC_MSI_IRQ
922 	struct list_head	msi_list;
923 #endif
924 
925 #ifdef CONFIG_NUMA
926 	int		numa_node;	/* NUMA node this device is close to */
927 #endif
928 	u64		*dma_mask;	/* dma mask (if dma'able device) */
929 	u64		coherent_dma_mask;/* Like dma_mask, but for
930 					     alloc_coherent mappings as
931 					     not all hardware supports
932 					     64 bit addresses for consistent
933 					     allocations such descriptors. */
934 	unsigned long	dma_pfn_offset;
935 
936 	struct device_dma_parameters *dma_parms;
937 
938 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
939 
940 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
941 					     override */
942 #ifdef CONFIG_DMA_CMA
943 	struct cma *cma_area;		/* contiguous memory area for dma
944 					   allocations */
945 #endif
946 	/* arch specific additions */
947 	struct dev_archdata	archdata;
948 
949 	struct device_node	*of_node; /* associated device tree node */
950 	struct fwnode_handle	*fwnode; /* firmware device node */
951 
952 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
953 	u32			id;	/* device instance */
954 
955 	spinlock_t		devres_lock;
956 	struct list_head	devres_head;
957 
958 	struct klist_node	knode_class;
959 	struct class		*class;
960 	const struct attribute_group **groups;	/* optional groups */
961 
962 	void	(*release)(struct device *dev);
963 	struct iommu_group	*iommu_group;
964 	struct iommu_fwspec	*iommu_fwspec;
965 
966 	bool			offline_disabled:1;
967 	bool			offline:1;
968 };
969 
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 
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
991 static inline int dev_to_node(struct device *dev)
992 {
993 	return dev->numa_node;
994 }
995 static inline void set_dev_node(struct device *dev, int node)
996 {
997 	dev->numa_node = node;
998 }
999 #else
1000 static inline int dev_to_node(struct device *dev)
1001 {
1002 	return -1;
1003 }
1004 static inline void set_dev_node(struct device *dev, int node)
1005 {
1006 }
1007 #endif
1008 
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 
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 
1025 static inline void *dev_get_drvdata(const struct device *dev)
1026 {
1027 	return dev->driver_data;
1028 }
1029 
1030 static inline void dev_set_drvdata(struct device *dev, void *data)
1031 {
1032 	dev->driver_data = data;
1033 }
1034 
1035 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
1036 {
1037 	return dev ? dev->power.subsys_data : NULL;
1038 }
1039 
1040 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
1041 {
1042 	return dev->kobj.uevent_suppress;
1043 }
1044 
1045 static inline void dev_set_uevent_suppress(struct device *dev, int val)
1046 {
1047 	dev->kobj.uevent_suppress = val;
1048 }
1049 
1050 static inline int device_is_registered(struct device *dev)
1051 {
1052 	return dev->kobj.state_in_sysfs;
1053 }
1054 
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 
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 
1067 static inline bool device_async_suspend_enabled(struct device *dev)
1068 {
1069 	return !!dev->power.async_suspend;
1070 }
1071 
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 
1079 static inline void device_lock(struct device *dev)
1080 {
1081 	mutex_lock(&dev->mutex);
1082 }
1083 
1084 static inline int device_lock_interruptible(struct device *dev)
1085 {
1086 	return mutex_lock_interruptible(&dev->mutex);
1087 }
1088 
1089 static inline int device_trylock(struct device *dev)
1090 {
1091 	return mutex_trylock(&dev->mutex);
1092 }
1093 
1094 static inline void device_unlock(struct device *dev)
1095 {
1096 	mutex_unlock(&dev->mutex);
1097 }
1098 
1099 static inline void device_lock_assert(struct device *dev)
1100 {
1101 	lockdep_assert_held(&dev->mutex);
1102 }
1103 
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 
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 
1147 static inline int dev_num_vf(struct device *dev)
1148 {
1149 	if (dev->bus && dev->bus->num_vf)
1150 		return dev->bus->num_vf(dev);
1151 	return 0;
1152 }
1153 
1154 /*
1155  * Root device objects for grouping under /sys/devices
1156  */
1157 extern struct device *__root_device_register(const char *name,
1158 					     struct module *owner);
1159 
1160 /* This is a macro to avoid include problems with THIS_MODULE */
1161 #define root_device_register(name) \
1162 	__root_device_register(name, THIS_MODULE)
1163 
1164 extern void root_device_unregister(struct device *root);
1165 
1166 static inline void *dev_get_platdata(const struct device *dev)
1167 {
1168 	return dev->platform_data;
1169 }
1170 
1171 /*
1172  * Manual binding of a device to driver. See drivers/base/bus.c
1173  * for information on use.
1174  */
1175 extern int __must_check device_bind_driver(struct device *dev);
1176 extern void device_release_driver(struct device *dev);
1177 extern int  __must_check device_attach(struct device *dev);
1178 extern int __must_check driver_attach(struct device_driver *drv);
1179 extern void device_initial_probe(struct device *dev);
1180 extern int __must_check device_reprobe(struct device *dev);
1181 
1182 extern bool device_is_bound(struct device *dev);
1183 
1184 /*
1185  * Easy functions for dynamically creating devices on the fly
1186  */
1187 extern __printf(5, 0)
1188 struct device *device_create_vargs(struct class *cls, struct device *parent,
1189 				   dev_t devt, void *drvdata,
1190 				   const char *fmt, va_list vargs);
1191 extern __printf(5, 6)
1192 struct device *device_create(struct class *cls, struct device *parent,
1193 			     dev_t devt, void *drvdata,
1194 			     const char *fmt, ...);
1195 extern __printf(6, 7)
1196 struct device *device_create_with_groups(struct class *cls,
1197 			     struct device *parent, dev_t devt, void *drvdata,
1198 			     const struct attribute_group **groups,
1199 			     const char *fmt, ...);
1200 extern void device_destroy(struct class *cls, dev_t devt);
1201 
1202 /*
1203  * Platform "fixup" functions - allow the platform to have their say
1204  * about devices and actions that the general device layer doesn't
1205  * know about.
1206  */
1207 /* Notify platform of device discovery */
1208 extern int (*platform_notify)(struct device *dev);
1209 
1210 extern int (*platform_notify_remove)(struct device *dev);
1211 
1212 
1213 /*
1214  * get_device - atomically increment the reference count for the device.
1215  *
1216  */
1217 extern struct device *get_device(struct device *dev);
1218 extern void put_device(struct device *dev);
1219 
1220 #ifdef CONFIG_DEVTMPFS
1221 extern int devtmpfs_create_node(struct device *dev);
1222 extern int devtmpfs_delete_node(struct device *dev);
1223 extern int devtmpfs_mount(const char *mntdir);
1224 #else
1225 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
1226 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
1227 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
1228 #endif
1229 
1230 /* drivers/base/power/shutdown.c */
1231 extern void device_shutdown(void);
1232 
1233 /* debugging and troubleshooting/diagnostic helpers. */
1234 extern const char *dev_driver_string(const struct device *dev);
1235 
1236 /* Device links interface. */
1237 struct device_link *device_link_add(struct device *consumer,
1238 				    struct device *supplier, u32 flags);
1239 void device_link_del(struct device_link *link);
1240 
1241 #ifdef CONFIG_PRINTK
1242 
1243 extern __printf(3, 0)
1244 int dev_vprintk_emit(int level, const struct device *dev,
1245 		     const char *fmt, va_list args);
1246 extern __printf(3, 4)
1247 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...);
1248 
1249 extern __printf(3, 4)
1250 void dev_printk(const char *level, const struct device *dev,
1251 		const char *fmt, ...);
1252 extern __printf(2, 3)
1253 void dev_emerg(const struct device *dev, const char *fmt, ...);
1254 extern __printf(2, 3)
1255 void dev_alert(const struct device *dev, const char *fmt, ...);
1256 extern __printf(2, 3)
1257 void dev_crit(const struct device *dev, const char *fmt, ...);
1258 extern __printf(2, 3)
1259 void dev_err(const struct device *dev, const char *fmt, ...);
1260 extern __printf(2, 3)
1261 void dev_warn(const struct device *dev, const char *fmt, ...);
1262 extern __printf(2, 3)
1263 void dev_notice(const struct device *dev, const char *fmt, ...);
1264 extern __printf(2, 3)
1265 void _dev_info(const struct device *dev, const char *fmt, ...);
1266 
1267 #else
1268 
1269 static inline __printf(3, 0)
1270 int dev_vprintk_emit(int level, const struct device *dev,
1271 		     const char *fmt, va_list args)
1272 { return 0; }
1273 static inline __printf(3, 4)
1274 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
1275 { return 0; }
1276 
1277 static inline void __dev_printk(const char *level, const struct device *dev,
1278 				struct va_format *vaf)
1279 {}
1280 static inline __printf(3, 4)
1281 void dev_printk(const char *level, const struct device *dev,
1282 		const char *fmt, ...)
1283 {}
1284 
1285 static inline __printf(2, 3)
1286 void dev_emerg(const struct device *dev, const char *fmt, ...)
1287 {}
1288 static inline __printf(2, 3)
1289 void dev_crit(const struct device *dev, const char *fmt, ...)
1290 {}
1291 static inline __printf(2, 3)
1292 void dev_alert(const struct device *dev, const char *fmt, ...)
1293 {}
1294 static inline __printf(2, 3)
1295 void dev_err(const struct device *dev, const char *fmt, ...)
1296 {}
1297 static inline __printf(2, 3)
1298 void dev_warn(const struct device *dev, const char *fmt, ...)
1299 {}
1300 static inline __printf(2, 3)
1301 void dev_notice(const struct device *dev, const char *fmt, ...)
1302 {}
1303 static inline __printf(2, 3)
1304 void _dev_info(const struct device *dev, const char *fmt, ...)
1305 {}
1306 
1307 #endif
1308 
1309 /*
1310  * Stupid hackaround for existing uses of non-printk uses dev_info
1311  *
1312  * Note that the definition of dev_info below is actually _dev_info
1313  * and a macro is used to avoid redefining dev_info
1314  */
1315 
1316 #define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)
1317 
1318 #if defined(CONFIG_DYNAMIC_DEBUG)
1319 #define dev_dbg(dev, format, ...)		     \
1320 do {						     \
1321 	dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
1322 } while (0)
1323 #elif defined(DEBUG)
1324 #define dev_dbg(dev, format, arg...)		\
1325 	dev_printk(KERN_DEBUG, dev, format, ##arg)
1326 #else
1327 #define dev_dbg(dev, format, arg...)				\
1328 ({								\
1329 	if (0)							\
1330 		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
1331 })
1332 #endif
1333 
1334 #ifdef CONFIG_PRINTK
1335 #define dev_level_once(dev_level, dev, fmt, ...)			\
1336 do {									\
1337 	static bool __print_once __read_mostly;				\
1338 									\
1339 	if (!__print_once) {						\
1340 		__print_once = true;					\
1341 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1342 	}								\
1343 } while (0)
1344 #else
1345 #define dev_level_once(dev_level, dev, fmt, ...)			\
1346 do {									\
1347 	if (0)								\
1348 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1349 } while (0)
1350 #endif
1351 
1352 #define dev_emerg_once(dev, fmt, ...)					\
1353 	dev_level_once(dev_emerg, dev, fmt, ##__VA_ARGS__)
1354 #define dev_alert_once(dev, fmt, ...)					\
1355 	dev_level_once(dev_alert, dev, fmt, ##__VA_ARGS__)
1356 #define dev_crit_once(dev, fmt, ...)					\
1357 	dev_level_once(dev_crit, dev, fmt, ##__VA_ARGS__)
1358 #define dev_err_once(dev, fmt, ...)					\
1359 	dev_level_once(dev_err, dev, fmt, ##__VA_ARGS__)
1360 #define dev_warn_once(dev, fmt, ...)					\
1361 	dev_level_once(dev_warn, dev, fmt, ##__VA_ARGS__)
1362 #define dev_notice_once(dev, fmt, ...)					\
1363 	dev_level_once(dev_notice, dev, fmt, ##__VA_ARGS__)
1364 #define dev_info_once(dev, fmt, ...)					\
1365 	dev_level_once(dev_info, dev, fmt, ##__VA_ARGS__)
1366 #define dev_dbg_once(dev, fmt, ...)					\
1367 	dev_level_once(dev_dbg, dev, fmt, ##__VA_ARGS__)
1368 
1369 #define dev_level_ratelimited(dev_level, dev, fmt, ...)			\
1370 do {									\
1371 	static DEFINE_RATELIMIT_STATE(_rs,				\
1372 				      DEFAULT_RATELIMIT_INTERVAL,	\
1373 				      DEFAULT_RATELIMIT_BURST);		\
1374 	if (__ratelimit(&_rs))						\
1375 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1376 } while (0)
1377 
1378 #define dev_emerg_ratelimited(dev, fmt, ...)				\
1379 	dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__)
1380 #define dev_alert_ratelimited(dev, fmt, ...)				\
1381 	dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__)
1382 #define dev_crit_ratelimited(dev, fmt, ...)				\
1383 	dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__)
1384 #define dev_err_ratelimited(dev, fmt, ...)				\
1385 	dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__)
1386 #define dev_warn_ratelimited(dev, fmt, ...)				\
1387 	dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__)
1388 #define dev_notice_ratelimited(dev, fmt, ...)				\
1389 	dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__)
1390 #define dev_info_ratelimited(dev, fmt, ...)				\
1391 	dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__)
1392 #if defined(CONFIG_DYNAMIC_DEBUG)
1393 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
1394 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1395 do {									\
1396 	static DEFINE_RATELIMIT_STATE(_rs,				\
1397 				      DEFAULT_RATELIMIT_INTERVAL,	\
1398 				      DEFAULT_RATELIMIT_BURST);		\
1399 	DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);			\
1400 	if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) &&	\
1401 	    __ratelimit(&_rs))						\
1402 		__dynamic_dev_dbg(&descriptor, dev, fmt,		\
1403 				  ##__VA_ARGS__);			\
1404 } while (0)
1405 #elif defined(DEBUG)
1406 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1407 do {									\
1408 	static DEFINE_RATELIMIT_STATE(_rs,				\
1409 				      DEFAULT_RATELIMIT_INTERVAL,	\
1410 				      DEFAULT_RATELIMIT_BURST);		\
1411 	if (__ratelimit(&_rs))						\
1412 		dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__);	\
1413 } while (0)
1414 #else
1415 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1416 do {									\
1417 	if (0)								\
1418 		dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__);	\
1419 } while (0)
1420 #endif
1421 
1422 #ifdef VERBOSE_DEBUG
1423 #define dev_vdbg	dev_dbg
1424 #else
1425 #define dev_vdbg(dev, format, arg...)				\
1426 ({								\
1427 	if (0)							\
1428 		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
1429 })
1430 #endif
1431 
1432 /*
1433  * dev_WARN*() acts like dev_printk(), but with the key difference of
1434  * using WARN/WARN_ONCE to include file/line information and a backtrace.
1435  */
1436 #define dev_WARN(dev, format, arg...) \
1437 	WARN(1, "%s %s: " format, dev_driver_string(dev), dev_name(dev), ## arg);
1438 
1439 #define dev_WARN_ONCE(dev, condition, format, arg...) \
1440 	WARN_ONCE(condition, "%s %s: " format, \
1441 			dev_driver_string(dev), dev_name(dev), ## arg)
1442 
1443 /* Create alias, so I can be autoloaded. */
1444 #define MODULE_ALIAS_CHARDEV(major,minor) \
1445 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1446 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1447 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
1448 
1449 #ifdef CONFIG_SYSFS_DEPRECATED
1450 extern long sysfs_deprecated;
1451 #else
1452 #define sysfs_deprecated 0
1453 #endif
1454 
1455 /**
1456  * module_driver() - Helper macro for drivers that don't do anything
1457  * special in module init/exit. This eliminates a lot of boilerplate.
1458  * Each module may only use this macro once, and calling it replaces
1459  * module_init() and module_exit().
1460  *
1461  * @__driver: driver name
1462  * @__register: register function for this driver type
1463  * @__unregister: unregister function for this driver type
1464  * @...: Additional arguments to be passed to __register and __unregister.
1465  *
1466  * Use this macro to construct bus specific macros for registering
1467  * drivers, and do not use it on its own.
1468  */
1469 #define module_driver(__driver, __register, __unregister, ...) \
1470 static int __init __driver##_init(void) \
1471 { \
1472 	return __register(&(__driver) , ##__VA_ARGS__); \
1473 } \
1474 module_init(__driver##_init); \
1475 static void __exit __driver##_exit(void) \
1476 { \
1477 	__unregister(&(__driver) , ##__VA_ARGS__); \
1478 } \
1479 module_exit(__driver##_exit);
1480 
1481 /**
1482  * builtin_driver() - Helper macro for drivers that don't do anything
1483  * special in init and have no exit. This eliminates some boilerplate.
1484  * Each driver may only use this macro once, and calling it replaces
1485  * device_initcall (or in some cases, the legacy __initcall).  This is
1486  * meant to be a direct parallel of module_driver() above but without
1487  * the __exit stuff that is not used for builtin cases.
1488  *
1489  * @__driver: driver name
1490  * @__register: register function for this driver type
1491  * @...: Additional arguments to be passed to __register
1492  *
1493  * Use this macro to construct bus specific macros for registering
1494  * drivers, and do not use it on its own.
1495  */
1496 #define builtin_driver(__driver, __register, ...) \
1497 static int __init __driver##_init(void) \
1498 { \
1499 	return __register(&(__driver) , ##__VA_ARGS__); \
1500 } \
1501 device_initcall(__driver##_init);
1502 
1503 #endif /* _DEVICE_H_ */
1504