xref: /linux-6.15/include/linux/device.h (revision 00a62703)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * device.h - generic, centralized driver model
4  *
5  * Copyright (c) 2001-2003 Patrick Mochel <[email protected]>
6  * Copyright (c) 2004-2009 Greg Kroah-Hartman <[email protected]>
7  * Copyright (c) 2008-2009 Novell Inc.
8  *
9  * See Documentation/driver-model/ for more information.
10  */
11 
12 #ifndef _DEVICE_H_
13 #define _DEVICE_H_
14 
15 #include <linux/ioport.h>
16 #include <linux/kobject.h>
17 #include <linux/klist.h>
18 #include <linux/list.h>
19 #include <linux/lockdep.h>
20 #include <linux/compiler.h>
21 #include <linux/types.h>
22 #include <linux/mutex.h>
23 #include <linux/pm.h>
24 #include <linux/atomic.h>
25 #include <linux/ratelimit.h>
26 #include <linux/uidgid.h>
27 #include <linux/gfp.h>
28 #include <asm/device.h>
29 
30 struct device;
31 struct device_private;
32 struct device_driver;
33 struct driver_private;
34 struct module;
35 struct class;
36 struct subsys_private;
37 struct bus_type;
38 struct device_node;
39 struct fwnode_handle;
40 struct iommu_ops;
41 struct iommu_group;
42 struct iommu_fwspec;
43 struct dev_pin_info;
44 
45 struct bus_attribute {
46 	struct attribute	attr;
47 	ssize_t (*show)(struct bus_type *bus, char *buf);
48 	ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
49 };
50 
51 #define BUS_ATTR(_name, _mode, _show, _store)	\
52 	struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)
53 #define BUS_ATTR_RW(_name) \
54 	struct bus_attribute bus_attr_##_name = __ATTR_RW(_name)
55 #define BUS_ATTR_RO(_name) \
56 	struct bus_attribute bus_attr_##_name = __ATTR_RO(_name)
57 
58 extern int __must_check bus_create_file(struct bus_type *,
59 					struct bus_attribute *);
60 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
61 
62 /**
63  * struct bus_type - The bus type of the device
64  *
65  * @name:	The name of the bus.
66  * @dev_name:	Used for subsystems to enumerate devices like ("foo%u", dev->id).
67  * @dev_root:	Default device to use as the parent.
68  * @bus_groups:	Default attributes of the bus.
69  * @dev_groups:	Default attributes of the devices on the bus.
70  * @drv_groups: Default attributes of the device drivers on the bus.
71  * @match:	Called, perhaps multiple times, whenever a new device or driver
72  *		is added for this bus. It should return a positive value if the
73  *		given device can be handled by the given driver and zero
74  *		otherwise. It may also return error code if determining that
75  *		the driver supports the device is not possible. In case of
76  *		-EPROBE_DEFER it will queue the device for deferred probing.
77  * @uevent:	Called when a device is added, removed, or a few other things
78  *		that generate uevents to add the environment variables.
79  * @probe:	Called when a new device or driver add to this bus, and callback
80  *		the specific driver's probe to initial the matched device.
81  * @remove:	Called when a device removed from this bus.
82  * @shutdown:	Called at shut-down time to quiesce the device.
83  *
84  * @online:	Called to put the device back online (after offlining it).
85  * @offline:	Called to put the device offline for hot-removal. May fail.
86  *
87  * @suspend:	Called when a device on this bus wants to go to sleep mode.
88  * @resume:	Called to bring a device on this bus out of sleep mode.
89  * @num_vf:	Called to find out how many virtual functions a device on this
90  *		bus supports.
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  * @force_dma:	Assume devices on this bus should be set up by dma_configure()
100  * 		even if DMA capability is not explicitly described by firmware.
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 	const struct attribute_group **bus_groups;
116 	const struct attribute_group **dev_groups;
117 	const struct attribute_group **drv_groups;
118 
119 	int (*match)(struct device *dev, struct device_driver *drv);
120 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
121 	int (*probe)(struct device *dev);
122 	int (*remove)(struct device *dev);
123 	void (*shutdown)(struct device *dev);
124 
125 	int (*online)(struct device *dev);
126 	int (*offline)(struct device *dev);
127 
128 	int (*suspend)(struct device *dev, pm_message_t state);
129 	int (*resume)(struct device *dev);
130 
131 	int (*num_vf)(struct device *dev);
132 
133 	const struct dev_pm_ops *pm;
134 
135 	const struct iommu_ops *iommu_ops;
136 
137 	struct subsys_private *p;
138 	struct lock_class_key lock_key;
139 
140 	bool force_dma;
141 };
142 
143 extern int __must_check bus_register(struct bus_type *bus);
144 
145 extern void bus_unregister(struct bus_type *bus);
146 
147 extern int __must_check bus_rescan_devices(struct bus_type *bus);
148 
149 /* iterator helpers for buses */
150 struct subsys_dev_iter {
151 	struct klist_iter		ki;
152 	const struct device_type	*type;
153 };
154 void subsys_dev_iter_init(struct subsys_dev_iter *iter,
155 			 struct bus_type *subsys,
156 			 struct device *start,
157 			 const struct device_type *type);
158 struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter);
159 void subsys_dev_iter_exit(struct subsys_dev_iter *iter);
160 
161 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
162 		     int (*fn)(struct device *dev, void *data));
163 struct device *bus_find_device(struct bus_type *bus, struct device *start,
164 			       void *data,
165 			       int (*match)(struct device *dev, void *data));
166 struct device *bus_find_device_by_name(struct bus_type *bus,
167 				       struct device *start,
168 				       const char *name);
169 struct device *subsys_find_device_by_id(struct bus_type *bus, unsigned int id,
170 					struct device *hint);
171 int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
172 		     void *data, int (*fn)(struct device_driver *, void *));
173 void bus_sort_breadthfirst(struct bus_type *bus,
174 			   int (*compare)(const struct device *a,
175 					  const struct device *b));
176 /*
177  * Bus notifiers: Get notified of addition/removal of devices
178  * and binding/unbinding of drivers to devices.
179  * In the long run, it should be a replacement for the platform
180  * notify hooks.
181  */
182 struct notifier_block;
183 
184 extern int bus_register_notifier(struct bus_type *bus,
185 				 struct notifier_block *nb);
186 extern int bus_unregister_notifier(struct bus_type *bus,
187 				   struct notifier_block *nb);
188 
189 /* All 4 notifers below get called with the target struct device *
190  * as an argument. Note that those functions are likely to be called
191  * with the device lock held in the core, so be careful.
192  */
193 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
194 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device to be removed */
195 #define BUS_NOTIFY_REMOVED_DEVICE	0x00000003 /* device removed */
196 #define BUS_NOTIFY_BIND_DRIVER		0x00000004 /* driver about to be
197 						      bound */
198 #define BUS_NOTIFY_BOUND_DRIVER		0x00000005 /* driver bound to device */
199 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000006 /* driver about to be
200 						      unbound */
201 #define BUS_NOTIFY_UNBOUND_DRIVER	0x00000007 /* driver is unbound
202 						      from the device */
203 #define BUS_NOTIFY_DRIVER_NOT_BOUND	0x00000008 /* driver fails to be bound */
204 
205 extern struct kset *bus_get_kset(struct bus_type *bus);
206 extern struct klist *bus_get_device_klist(struct bus_type *bus);
207 
208 /**
209  * enum probe_type - device driver probe type to try
210  *	Device drivers may opt in for special handling of their
211  *	respective probe routines. This tells the core what to
212  *	expect and prefer.
213  *
214  * @PROBE_DEFAULT_STRATEGY: Used by drivers that work equally well
215  *	whether probed synchronously or asynchronously.
216  * @PROBE_PREFER_ASYNCHRONOUS: Drivers for "slow" devices which
217  *	probing order is not essential for booting the system may
218  *	opt into executing their probes asynchronously.
219  * @PROBE_FORCE_SYNCHRONOUS: Use this to annotate drivers that need
220  *	their probe routines to run synchronously with driver and
221  *	device registration (with the exception of -EPROBE_DEFER
222  *	handling - re-probing always ends up being done asynchronously).
223  *
224  * Note that the end goal is to switch the kernel to use asynchronous
225  * probing by default, so annotating drivers with
226  * %PROBE_PREFER_ASYNCHRONOUS is a temporary measure that allows us
227  * to speed up boot process while we are validating the rest of the
228  * drivers.
229  */
230 enum probe_type {
231 	PROBE_DEFAULT_STRATEGY,
232 	PROBE_PREFER_ASYNCHRONOUS,
233 	PROBE_FORCE_SYNCHRONOUS,
234 };
235 
236 /**
237  * struct device_driver - The basic device driver structure
238  * @name:	Name of the device driver.
239  * @bus:	The bus which the device of this driver belongs to.
240  * @owner:	The module owner.
241  * @mod_name:	Used for built-in modules.
242  * @suppress_bind_attrs: Disables bind/unbind via sysfs.
243  * @probe_type:	Type of the probe (synchronous or asynchronous) to use.
244  * @of_match_table: The open firmware table.
245  * @acpi_match_table: The ACPI match table.
246  * @probe:	Called to query the existence of a specific device,
247  *		whether this driver can work with it, and bind the driver
248  *		to a specific device.
249  * @remove:	Called when the device is removed from the system to
250  *		unbind a device from this driver.
251  * @shutdown:	Called at shut-down time to quiesce the device.
252  * @suspend:	Called to put the device to sleep mode. Usually to a
253  *		low power state.
254  * @resume:	Called to bring a device from sleep mode.
255  * @groups:	Default attributes that get created by the driver core
256  *		automatically.
257  * @pm:		Power management operations of the device which matched
258  *		this driver.
259  * @coredump:	Called when sysfs entry is written to. The device driver
260  *		is expected to call the dev_coredump API resulting in a
261  *		uevent.
262  * @p:		Driver core's private data, no one other than the driver
263  *		core can touch this.
264  *
265  * The device driver-model tracks all of the drivers known to the system.
266  * The main reason for this tracking is to enable the driver core to match
267  * up drivers with new devices. Once drivers are known objects within the
268  * system, however, a number of other things become possible. Device drivers
269  * can export information and configuration variables that are independent
270  * of any specific device.
271  */
272 struct device_driver {
273 	const char		*name;
274 	struct bus_type		*bus;
275 
276 	struct module		*owner;
277 	const char		*mod_name;	/* used for built-in modules */
278 
279 	bool suppress_bind_attrs;	/* disables bind/unbind via sysfs */
280 	enum probe_type probe_type;
281 
282 	const struct of_device_id	*of_match_table;
283 	const struct acpi_device_id	*acpi_match_table;
284 
285 	int (*probe) (struct device *dev);
286 	int (*remove) (struct device *dev);
287 	void (*shutdown) (struct device *dev);
288 	int (*suspend) (struct device *dev, pm_message_t state);
289 	int (*resume) (struct device *dev);
290 	const struct attribute_group **groups;
291 
292 	const struct dev_pm_ops *pm;
293 	void (*coredump) (struct device *dev);
294 
295 	struct driver_private *p;
296 };
297 
298 
299 extern int __must_check driver_register(struct device_driver *drv);
300 extern void driver_unregister(struct device_driver *drv);
301 
302 extern struct device_driver *driver_find(const char *name,
303 					 struct bus_type *bus);
304 extern int driver_probe_done(void);
305 extern void wait_for_device_probe(void);
306 
307 /* sysfs interface for exporting driver attributes */
308 
309 struct driver_attribute {
310 	struct attribute attr;
311 	ssize_t (*show)(struct device_driver *driver, char *buf);
312 	ssize_t (*store)(struct device_driver *driver, const char *buf,
313 			 size_t count);
314 };
315 
316 #define DRIVER_ATTR_RW(_name) \
317 	struct driver_attribute driver_attr_##_name = __ATTR_RW(_name)
318 #define DRIVER_ATTR_RO(_name) \
319 	struct driver_attribute driver_attr_##_name = __ATTR_RO(_name)
320 #define DRIVER_ATTR_WO(_name) \
321 	struct driver_attribute driver_attr_##_name = __ATTR_WO(_name)
322 
323 extern int __must_check driver_create_file(struct device_driver *driver,
324 					const struct driver_attribute *attr);
325 extern void driver_remove_file(struct device_driver *driver,
326 			       const struct driver_attribute *attr);
327 
328 extern int __must_check driver_for_each_device(struct device_driver *drv,
329 					       struct device *start,
330 					       void *data,
331 					       int (*fn)(struct device *dev,
332 							 void *));
333 struct device *driver_find_device(struct device_driver *drv,
334 				  struct device *start, void *data,
335 				  int (*match)(struct device *dev, void *data));
336 
337 /**
338  * struct subsys_interface - interfaces to device functions
339  * @name:       name of the device function
340  * @subsys:     subsytem of the devices to attach to
341  * @node:       the list of functions registered at the subsystem
342  * @add_dev:    device hookup to device function handler
343  * @remove_dev: device hookup to device function handler
344  *
345  * Simple interfaces attached to a subsystem. Multiple interfaces can
346  * attach to a subsystem and its devices. Unlike drivers, they do not
347  * exclusively claim or control devices. Interfaces usually represent
348  * a specific functionality of a subsystem/class of devices.
349  */
350 struct subsys_interface {
351 	const char *name;
352 	struct bus_type *subsys;
353 	struct list_head node;
354 	int (*add_dev)(struct device *dev, struct subsys_interface *sif);
355 	void (*remove_dev)(struct device *dev, struct subsys_interface *sif);
356 };
357 
358 int subsys_interface_register(struct subsys_interface *sif);
359 void subsys_interface_unregister(struct subsys_interface *sif);
360 
361 int subsys_system_register(struct bus_type *subsys,
362 			   const struct attribute_group **groups);
363 int subsys_virtual_register(struct bus_type *subsys,
364 			    const struct attribute_group **groups);
365 
366 /**
367  * struct class - device classes
368  * @name:	Name of the class.
369  * @owner:	The module owner.
370  * @class_groups: Default attributes of this class.
371  * @dev_groups:	Default attributes of the devices that belong to the class.
372  * @dev_kobj:	The kobject that represents this class and links it into the hierarchy.
373  * @dev_uevent:	Called when a device is added, removed from this class, or a
374  *		few other things that generate uevents to add the environment
375  *		variables.
376  * @devnode:	Callback to provide the devtmpfs.
377  * @class_release: Called to release this class.
378  * @dev_release: Called to release the device.
379  * @shutdown_pre: Called at shut-down time before driver shutdown.
380  * @ns_type:	Callbacks so sysfs can detemine namespaces.
381  * @namespace:	Namespace of the device belongs to this class.
382  * @pm:		The default device power management operations of this class.
383  * @p:		The private data of the driver core, no one other than the
384  *		driver core can touch this.
385  *
386  * A class is a higher-level view of a device that abstracts out low-level
387  * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
388  * at the class level, they are all simply disks. Classes allow user space
389  * to work with devices based on what they do, rather than how they are
390  * connected or how they work.
391  */
392 struct class {
393 	const char		*name;
394 	struct module		*owner;
395 
396 	const struct attribute_group	**class_groups;
397 	const struct attribute_group	**dev_groups;
398 	struct kobject			*dev_kobj;
399 
400 	int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
401 	char *(*devnode)(struct device *dev, umode_t *mode);
402 
403 	void (*class_release)(struct class *class);
404 	void (*dev_release)(struct device *dev);
405 
406 	int (*shutdown_pre)(struct device *dev);
407 
408 	const struct kobj_ns_type_operations *ns_type;
409 	const void *(*namespace)(struct device *dev);
410 
411 	const struct dev_pm_ops *pm;
412 
413 	struct subsys_private *p;
414 };
415 
416 struct class_dev_iter {
417 	struct klist_iter		ki;
418 	const struct device_type	*type;
419 };
420 
421 extern struct kobject *sysfs_dev_block_kobj;
422 extern struct kobject *sysfs_dev_char_kobj;
423 extern int __must_check __class_register(struct class *class,
424 					 struct lock_class_key *key);
425 extern void class_unregister(struct class *class);
426 
427 /* This is a #define to keep the compiler from merging different
428  * instances of the __key variable */
429 #define class_register(class)			\
430 ({						\
431 	static struct lock_class_key __key;	\
432 	__class_register(class, &__key);	\
433 })
434 
435 struct class_compat;
436 struct class_compat *class_compat_register(const char *name);
437 void class_compat_unregister(struct class_compat *cls);
438 int class_compat_create_link(struct class_compat *cls, struct device *dev,
439 			     struct device *device_link);
440 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
441 			      struct device *device_link);
442 
443 extern void class_dev_iter_init(struct class_dev_iter *iter,
444 				struct class *class,
445 				struct device *start,
446 				const struct device_type *type);
447 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
448 extern void class_dev_iter_exit(struct class_dev_iter *iter);
449 
450 extern int class_for_each_device(struct class *class, struct device *start,
451 				 void *data,
452 				 int (*fn)(struct device *dev, void *data));
453 extern struct device *class_find_device(struct class *class,
454 					struct device *start, const void *data,
455 					int (*match)(struct device *, const void *));
456 
457 struct class_attribute {
458 	struct attribute attr;
459 	ssize_t (*show)(struct class *class, struct class_attribute *attr,
460 			char *buf);
461 	ssize_t (*store)(struct class *class, struct class_attribute *attr,
462 			const char *buf, size_t count);
463 };
464 
465 #define CLASS_ATTR_RW(_name) \
466 	struct class_attribute class_attr_##_name = __ATTR_RW(_name)
467 #define CLASS_ATTR_RO(_name) \
468 	struct class_attribute class_attr_##_name = __ATTR_RO(_name)
469 #define CLASS_ATTR_WO(_name) \
470 	struct class_attribute class_attr_##_name = __ATTR_WO(_name)
471 
472 extern int __must_check class_create_file_ns(struct class *class,
473 					     const struct class_attribute *attr,
474 					     const void *ns);
475 extern void class_remove_file_ns(struct class *class,
476 				 const struct class_attribute *attr,
477 				 const void *ns);
478 
479 static inline int __must_check class_create_file(struct class *class,
480 					const struct class_attribute *attr)
481 {
482 	return class_create_file_ns(class, attr, NULL);
483 }
484 
485 static inline void class_remove_file(struct class *class,
486 				     const struct class_attribute *attr)
487 {
488 	return class_remove_file_ns(class, attr, NULL);
489 }
490 
491 /* Simple class attribute that is just a static string */
492 struct class_attribute_string {
493 	struct class_attribute attr;
494 	char *str;
495 };
496 
497 /* Currently read-only only */
498 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
499 	{ __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
500 #define CLASS_ATTR_STRING(_name, _mode, _str) \
501 	struct class_attribute_string class_attr_##_name = \
502 		_CLASS_ATTR_STRING(_name, _mode, _str)
503 
504 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
505                         char *buf);
506 
507 struct class_interface {
508 	struct list_head	node;
509 	struct class		*class;
510 
511 	int (*add_dev)		(struct device *, struct class_interface *);
512 	void (*remove_dev)	(struct device *, struct class_interface *);
513 };
514 
515 extern int __must_check class_interface_register(struct class_interface *);
516 extern void class_interface_unregister(struct class_interface *);
517 
518 extern struct class * __must_check __class_create(struct module *owner,
519 						  const char *name,
520 						  struct lock_class_key *key);
521 extern void class_destroy(struct class *cls);
522 
523 /* This is a #define to keep the compiler from merging different
524  * instances of the __key variable */
525 #define class_create(owner, name)		\
526 ({						\
527 	static struct lock_class_key __key;	\
528 	__class_create(owner, name, &__key);	\
529 })
530 
531 /*
532  * The type of device, "struct device" is embedded in. A class
533  * or bus can contain devices of different types
534  * like "partitions" and "disks", "mouse" and "event".
535  * This identifies the device type and carries type-specific
536  * information, equivalent to the kobj_type of a kobject.
537  * If "name" is specified, the uevent will contain it in
538  * the DEVTYPE variable.
539  */
540 struct device_type {
541 	const char *name;
542 	const struct attribute_group **groups;
543 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
544 	char *(*devnode)(struct device *dev, umode_t *mode,
545 			 kuid_t *uid, kgid_t *gid);
546 	void (*release)(struct device *dev);
547 
548 	const struct dev_pm_ops *pm;
549 };
550 
551 /* interface for exporting device attributes */
552 struct device_attribute {
553 	struct attribute	attr;
554 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
555 			char *buf);
556 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
557 			 const char *buf, size_t count);
558 };
559 
560 struct dev_ext_attribute {
561 	struct device_attribute attr;
562 	void *var;
563 };
564 
565 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
566 			  char *buf);
567 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
568 			   const char *buf, size_t count);
569 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
570 			char *buf);
571 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
572 			 const char *buf, size_t count);
573 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
574 			char *buf);
575 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
576 			 const char *buf, size_t count);
577 
578 #define DEVICE_ATTR(_name, _mode, _show, _store) \
579 	struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
580 #define DEVICE_ATTR_PREALLOC(_name, _mode, _show, _store) \
581 	struct device_attribute dev_attr_##_name = \
582 		__ATTR_PREALLOC(_name, _mode, _show, _store)
583 #define DEVICE_ATTR_RW(_name) \
584 	struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
585 #define DEVICE_ATTR_RO(_name) \
586 	struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
587 #define DEVICE_ATTR_WO(_name) \
588 	struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
589 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
590 	struct dev_ext_attribute dev_attr_##_name = \
591 		{ __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
592 #define DEVICE_INT_ATTR(_name, _mode, _var) \
593 	struct dev_ext_attribute dev_attr_##_name = \
594 		{ __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
595 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
596 	struct dev_ext_attribute dev_attr_##_name = \
597 		{ __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
598 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
599 	struct device_attribute dev_attr_##_name =		\
600 		__ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
601 
602 extern int device_create_file(struct device *device,
603 			      const struct device_attribute *entry);
604 extern void device_remove_file(struct device *dev,
605 			       const struct device_attribute *attr);
606 extern bool device_remove_file_self(struct device *dev,
607 				    const struct device_attribute *attr);
608 extern int __must_check device_create_bin_file(struct device *dev,
609 					const struct bin_attribute *attr);
610 extern void device_remove_bin_file(struct device *dev,
611 				   const struct bin_attribute *attr);
612 
613 /* device resource management */
614 typedef void (*dr_release_t)(struct device *dev, void *res);
615 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
616 
617 #ifdef CONFIG_DEBUG_DEVRES
618 extern void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
619 				 int nid, const char *name) __malloc;
620 #define devres_alloc(release, size, gfp) \
621 	__devres_alloc_node(release, size, gfp, NUMA_NO_NODE, #release)
622 #define devres_alloc_node(release, size, gfp, nid) \
623 	__devres_alloc_node(release, size, gfp, nid, #release)
624 #else
625 extern void *devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
626 			       int nid) __malloc;
627 static inline void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp)
628 {
629 	return devres_alloc_node(release, size, gfp, NUMA_NO_NODE);
630 }
631 #endif
632 
633 extern void devres_for_each_res(struct device *dev, dr_release_t release,
634 				dr_match_t match, void *match_data,
635 				void (*fn)(struct device *, void *, void *),
636 				void *data);
637 extern void devres_free(void *res);
638 extern void devres_add(struct device *dev, void *res);
639 extern void *devres_find(struct device *dev, dr_release_t release,
640 			 dr_match_t match, void *match_data);
641 extern void *devres_get(struct device *dev, void *new_res,
642 			dr_match_t match, void *match_data);
643 extern void *devres_remove(struct device *dev, dr_release_t release,
644 			   dr_match_t match, void *match_data);
645 extern int devres_destroy(struct device *dev, dr_release_t release,
646 			  dr_match_t match, void *match_data);
647 extern int devres_release(struct device *dev, dr_release_t release,
648 			  dr_match_t match, void *match_data);
649 
650 /* devres group */
651 extern void * __must_check devres_open_group(struct device *dev, void *id,
652 					     gfp_t gfp);
653 extern void devres_close_group(struct device *dev, void *id);
654 extern void devres_remove_group(struct device *dev, void *id);
655 extern int devres_release_group(struct device *dev, void *id);
656 
657 /* managed devm_k.alloc/kfree for device drivers */
658 extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __malloc;
659 extern __printf(3, 0)
660 char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt,
661 		      va_list ap) __malloc;
662 extern __printf(3, 4)
663 char *devm_kasprintf(struct device *dev, gfp_t gfp, const char *fmt, ...) __malloc;
664 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
665 {
666 	return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
667 }
668 static inline void *devm_kmalloc_array(struct device *dev,
669 				       size_t n, size_t size, gfp_t flags)
670 {
671 	if (size != 0 && n > SIZE_MAX / size)
672 		return NULL;
673 	return devm_kmalloc(dev, n * size, flags);
674 }
675 static inline void *devm_kcalloc(struct device *dev,
676 				 size_t n, size_t size, gfp_t flags)
677 {
678 	return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
679 }
680 extern void devm_kfree(struct device *dev, void *p);
681 extern char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
682 extern void *devm_kmemdup(struct device *dev, const void *src, size_t len,
683 			  gfp_t gfp);
684 
685 extern unsigned long devm_get_free_pages(struct device *dev,
686 					 gfp_t gfp_mask, unsigned int order);
687 extern void devm_free_pages(struct device *dev, unsigned long addr);
688 
689 void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
690 
691 /* allows to add/remove a custom action to devres stack */
692 int devm_add_action(struct device *dev, void (*action)(void *), void *data);
693 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
694 
695 static inline int devm_add_action_or_reset(struct device *dev,
696 					   void (*action)(void *), void *data)
697 {
698 	int ret;
699 
700 	ret = devm_add_action(dev, action, data);
701 	if (ret)
702 		action(data);
703 
704 	return ret;
705 }
706 
707 /**
708  * devm_alloc_percpu - Resource-managed alloc_percpu
709  * @dev: Device to allocate per-cpu memory for
710  * @type: Type to allocate per-cpu memory for
711  *
712  * Managed alloc_percpu. Per-cpu memory allocated with this function is
713  * automatically freed on driver detach.
714  *
715  * RETURNS:
716  * Pointer to allocated memory on success, NULL on failure.
717  */
718 #define devm_alloc_percpu(dev, type)      \
719 	((typeof(type) __percpu *)__devm_alloc_percpu((dev), sizeof(type), \
720 						      __alignof__(type)))
721 
722 void __percpu *__devm_alloc_percpu(struct device *dev, size_t size,
723 				   size_t align);
724 void devm_free_percpu(struct device *dev, void __percpu *pdata);
725 
726 struct device_dma_parameters {
727 	/*
728 	 * a low level driver may set these to teach IOMMU code about
729 	 * sg limitations.
730 	 */
731 	unsigned int max_segment_size;
732 	unsigned long segment_boundary_mask;
733 };
734 
735 /**
736  * struct device_connection - Device Connection Descriptor
737  * @endpoint: The names of the two devices connected together
738  * @id: Unique identifier for the connection
739  * @list: List head, private, for internal use only
740  */
741 struct device_connection {
742 	const char		*endpoint[2];
743 	const char		*id;
744 	struct list_head	list;
745 };
746 
747 void *device_connection_find_match(struct device *dev, const char *con_id,
748 				void *data,
749 				void *(*match)(struct device_connection *con,
750 					       int ep, void *data));
751 
752 struct device *device_connection_find(struct device *dev, const char *con_id);
753 
754 void device_connection_add(struct device_connection *con);
755 void device_connection_remove(struct device_connection *con);
756 
757 /**
758  * enum device_link_state - Device link states.
759  * @DL_STATE_NONE: The presence of the drivers is not being tracked.
760  * @DL_STATE_DORMANT: None of the supplier/consumer drivers is present.
761  * @DL_STATE_AVAILABLE: The supplier driver is present, but the consumer is not.
762  * @DL_STATE_CONSUMER_PROBE: The consumer is probing (supplier driver present).
763  * @DL_STATE_ACTIVE: Both the supplier and consumer drivers are present.
764  * @DL_STATE_SUPPLIER_UNBIND: The supplier driver is unbinding.
765  */
766 enum device_link_state {
767 	DL_STATE_NONE = -1,
768 	DL_STATE_DORMANT = 0,
769 	DL_STATE_AVAILABLE,
770 	DL_STATE_CONSUMER_PROBE,
771 	DL_STATE_ACTIVE,
772 	DL_STATE_SUPPLIER_UNBIND,
773 };
774 
775 /*
776  * Device link flags.
777  *
778  * STATELESS: The core won't track the presence of supplier/consumer drivers.
779  * AUTOREMOVE: Remove this link automatically on consumer driver unbind.
780  * PM_RUNTIME: If set, the runtime PM framework will use this link.
781  * RPM_ACTIVE: Run pm_runtime_get_sync() on the supplier during link creation.
782  */
783 #define DL_FLAG_STATELESS	BIT(0)
784 #define DL_FLAG_AUTOREMOVE	BIT(1)
785 #define DL_FLAG_PM_RUNTIME	BIT(2)
786 #define DL_FLAG_RPM_ACTIVE	BIT(3)
787 
788 /**
789  * struct device_link - Device link representation.
790  * @supplier: The device on the supplier end of the link.
791  * @s_node: Hook to the supplier device's list of links to consumers.
792  * @consumer: The device on the consumer end of the link.
793  * @c_node: Hook to the consumer device's list of links to suppliers.
794  * @status: The state of the link (with respect to the presence of drivers).
795  * @flags: Link flags.
796  * @rpm_active: Whether or not the consumer device is runtime-PM-active.
797  * @kref: Count repeated addition of the same link.
798  * @rcu_head: An RCU head to use for deferred execution of SRCU callbacks.
799  */
800 struct device_link {
801 	struct device *supplier;
802 	struct list_head s_node;
803 	struct device *consumer;
804 	struct list_head c_node;
805 	enum device_link_state status;
806 	u32 flags;
807 	bool rpm_active;
808 	struct kref kref;
809 #ifdef CONFIG_SRCU
810 	struct rcu_head rcu_head;
811 #endif
812 };
813 
814 /**
815  * enum dl_dev_state - Device driver presence tracking information.
816  * @DL_DEV_NO_DRIVER: There is no driver attached to the device.
817  * @DL_DEV_PROBING: A driver is probing.
818  * @DL_DEV_DRIVER_BOUND: The driver has been bound to the device.
819  * @DL_DEV_UNBINDING: The driver is unbinding from the device.
820  */
821 enum dl_dev_state {
822 	DL_DEV_NO_DRIVER = 0,
823 	DL_DEV_PROBING,
824 	DL_DEV_DRIVER_BOUND,
825 	DL_DEV_UNBINDING,
826 };
827 
828 /**
829  * struct dev_links_info - Device data related to device links.
830  * @suppliers: List of links to supplier devices.
831  * @consumers: List of links to consumer devices.
832  * @status: Driver status information.
833  */
834 struct dev_links_info {
835 	struct list_head suppliers;
836 	struct list_head consumers;
837 	enum dl_dev_state status;
838 };
839 
840 /**
841  * struct device - The basic device structure
842  * @parent:	The device's "parent" device, the device to which it is attached.
843  * 		In most cases, a parent device is some sort of bus or host
844  * 		controller. If parent is NULL, the device, is a top-level device,
845  * 		which is not usually what you want.
846  * @p:		Holds the private data of the driver core portions of the device.
847  * 		See the comment of the struct device_private for detail.
848  * @kobj:	A top-level, abstract class from which other classes are derived.
849  * @init_name:	Initial name of the device.
850  * @type:	The type of device.
851  * 		This identifies the device type and carries type-specific
852  * 		information.
853  * @mutex:	Mutex to synchronize calls to its driver.
854  * @bus:	Type of bus device is on.
855  * @driver:	Which driver has allocated this
856  * @platform_data: Platform data specific to the device.
857  * 		Example: For devices on custom boards, as typical of embedded
858  * 		and SOC based hardware, Linux often uses platform_data to point
859  * 		to board-specific structures describing devices and how they
860  * 		are wired.  That can include what ports are available, chip
861  * 		variants, which GPIO pins act in what additional roles, and so
862  * 		on.  This shrinks the "Board Support Packages" (BSPs) and
863  * 		minimizes board-specific #ifdefs in drivers.
864  * @driver_data: Private pointer for driver specific info.
865  * @links:	Links to suppliers and consumers of this device.
866  * @power:	For device power management.
867  *		See Documentation/driver-api/pm/devices.rst for details.
868  * @pm_domain:	Provide callbacks that are executed during system suspend,
869  * 		hibernation, system resume and during runtime PM transitions
870  * 		along with subsystem-level and driver-level callbacks.
871  * @pins:	For device pin management.
872  *		See Documentation/driver-api/pinctl.rst for details.
873  * @msi_list:	Hosts MSI descriptors
874  * @msi_domain: The generic MSI domain this device is using.
875  * @numa_node:	NUMA node this device is close to.
876  * @dma_ops:    DMA mapping operations for this device.
877  * @dma_mask:	Dma mask (if dma'ble device).
878  * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
879  * 		hardware supports 64-bit addresses for consistent allocations
880  * 		such descriptors.
881  * @dma_pfn_offset: offset of DMA memory range relatively of RAM
882  * @dma_parms:	A low level driver may set these to teach IOMMU code about
883  * 		segment limitations.
884  * @dma_pools:	Dma pools (if dma'ble device).
885  * @dma_mem:	Internal for coherent mem override.
886  * @cma_area:	Contiguous memory area for dma allocations
887  * @archdata:	For arch-specific additions.
888  * @of_node:	Associated device tree node.
889  * @fwnode:	Associated device node supplied by platform firmware.
890  * @devt:	For creating the sysfs "dev".
891  * @id:		device instance
892  * @devres_lock: Spinlock to protect the resource of the device.
893  * @devres_head: The resources list of the device.
894  * @knode_class: The node used to add the device to the class list.
895  * @class:	The class of the device.
896  * @groups:	Optional attribute groups.
897  * @release:	Callback to free the device after all references have
898  * 		gone away. This should be set by the allocator of the
899  * 		device (i.e. the bus driver that discovered the device).
900  * @iommu_group: IOMMU group the device belongs to.
901  * @iommu_fwspec: IOMMU-specific properties supplied by firmware.
902  *
903  * @offline_disabled: If set, the device is permanently online.
904  * @offline:	Set after successful invocation of bus type's .offline().
905  * @of_node_reused: Set if the device-tree node is shared with an ancestor
906  *              device.
907  *
908  * At the lowest level, every device in a Linux system is represented by an
909  * instance of struct device. The device structure contains the information
910  * that the device model core needs to model the system. Most subsystems,
911  * however, track additional information about the devices they host. As a
912  * result, it is rare for devices to be represented by bare device structures;
913  * instead, that structure, like kobject structures, is usually embedded within
914  * a higher-level representation of the device.
915  */
916 struct device {
917 	struct device		*parent;
918 
919 	struct device_private	*p;
920 
921 	struct kobject kobj;
922 	const char		*init_name; /* initial name of the device */
923 	const struct device_type *type;
924 
925 	struct mutex		mutex;	/* mutex to synchronize calls to
926 					 * its driver.
927 					 */
928 
929 	struct bus_type	*bus;		/* type of bus device is on */
930 	struct device_driver *driver;	/* which driver has allocated this
931 					   device */
932 	void		*platform_data;	/* Platform specific data, device
933 					   core doesn't touch it */
934 	void		*driver_data;	/* Driver data, set and get with
935 					   dev_set/get_drvdata */
936 	struct dev_links_info	links;
937 	struct dev_pm_info	power;
938 	struct dev_pm_domain	*pm_domain;
939 
940 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
941 	struct irq_domain	*msi_domain;
942 #endif
943 #ifdef CONFIG_PINCTRL
944 	struct dev_pin_info	*pins;
945 #endif
946 #ifdef CONFIG_GENERIC_MSI_IRQ
947 	struct list_head	msi_list;
948 #endif
949 
950 #ifdef CONFIG_NUMA
951 	int		numa_node;	/* NUMA node this device is close to */
952 #endif
953 	const struct dma_map_ops *dma_ops;
954 	u64		*dma_mask;	/* dma mask (if dma'able device) */
955 	u64		coherent_dma_mask;/* Like dma_mask, but for
956 					     alloc_coherent mappings as
957 					     not all hardware supports
958 					     64 bit addresses for consistent
959 					     allocations such descriptors. */
960 	unsigned long	dma_pfn_offset;
961 
962 	struct device_dma_parameters *dma_parms;
963 
964 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
965 
966 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
967 					     override */
968 #ifdef CONFIG_DMA_CMA
969 	struct cma *cma_area;		/* contiguous memory area for dma
970 					   allocations */
971 #endif
972 	/* arch specific additions */
973 	struct dev_archdata	archdata;
974 
975 	struct device_node	*of_node; /* associated device tree node */
976 	struct fwnode_handle	*fwnode; /* firmware device node */
977 
978 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
979 	u32			id;	/* device instance */
980 
981 	spinlock_t		devres_lock;
982 	struct list_head	devres_head;
983 
984 	struct klist_node	knode_class;
985 	struct class		*class;
986 	const struct attribute_group **groups;	/* optional groups */
987 
988 	void	(*release)(struct device *dev);
989 	struct iommu_group	*iommu_group;
990 	struct iommu_fwspec	*iommu_fwspec;
991 
992 	bool			offline_disabled:1;
993 	bool			offline:1;
994 	bool			of_node_reused:1;
995 };
996 
997 static inline struct device *kobj_to_dev(struct kobject *kobj)
998 {
999 	return container_of(kobj, struct device, kobj);
1000 }
1001 
1002 /* Get the wakeup routines, which depend on struct device */
1003 #include <linux/pm_wakeup.h>
1004 
1005 static inline const char *dev_name(const struct device *dev)
1006 {
1007 	/* Use the init name until the kobject becomes available */
1008 	if (dev->init_name)
1009 		return dev->init_name;
1010 
1011 	return kobject_name(&dev->kobj);
1012 }
1013 
1014 extern __printf(2, 3)
1015 int dev_set_name(struct device *dev, const char *name, ...);
1016 
1017 #ifdef CONFIG_NUMA
1018 static inline int dev_to_node(struct device *dev)
1019 {
1020 	return dev->numa_node;
1021 }
1022 static inline void set_dev_node(struct device *dev, int node)
1023 {
1024 	dev->numa_node = node;
1025 }
1026 #else
1027 static inline int dev_to_node(struct device *dev)
1028 {
1029 	return -1;
1030 }
1031 static inline void set_dev_node(struct device *dev, int node)
1032 {
1033 }
1034 #endif
1035 
1036 static inline struct irq_domain *dev_get_msi_domain(const struct device *dev)
1037 {
1038 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
1039 	return dev->msi_domain;
1040 #else
1041 	return NULL;
1042 #endif
1043 }
1044 
1045 static inline void dev_set_msi_domain(struct device *dev, struct irq_domain *d)
1046 {
1047 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
1048 	dev->msi_domain = d;
1049 #endif
1050 }
1051 
1052 static inline void *dev_get_drvdata(const struct device *dev)
1053 {
1054 	return dev->driver_data;
1055 }
1056 
1057 static inline void dev_set_drvdata(struct device *dev, void *data)
1058 {
1059 	dev->driver_data = data;
1060 }
1061 
1062 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
1063 {
1064 	return dev ? dev->power.subsys_data : NULL;
1065 }
1066 
1067 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
1068 {
1069 	return dev->kobj.uevent_suppress;
1070 }
1071 
1072 static inline void dev_set_uevent_suppress(struct device *dev, int val)
1073 {
1074 	dev->kobj.uevent_suppress = val;
1075 }
1076 
1077 static inline int device_is_registered(struct device *dev)
1078 {
1079 	return dev->kobj.state_in_sysfs;
1080 }
1081 
1082 static inline void device_enable_async_suspend(struct device *dev)
1083 {
1084 	if (!dev->power.is_prepared)
1085 		dev->power.async_suspend = true;
1086 }
1087 
1088 static inline void device_disable_async_suspend(struct device *dev)
1089 {
1090 	if (!dev->power.is_prepared)
1091 		dev->power.async_suspend = false;
1092 }
1093 
1094 static inline bool device_async_suspend_enabled(struct device *dev)
1095 {
1096 	return !!dev->power.async_suspend;
1097 }
1098 
1099 static inline void dev_pm_syscore_device(struct device *dev, bool val)
1100 {
1101 #ifdef CONFIG_PM_SLEEP
1102 	dev->power.syscore = val;
1103 #endif
1104 }
1105 
1106 static inline void dev_pm_set_driver_flags(struct device *dev, u32 flags)
1107 {
1108 	dev->power.driver_flags = flags;
1109 }
1110 
1111 static inline bool dev_pm_test_driver_flags(struct device *dev, u32 flags)
1112 {
1113 	return !!(dev->power.driver_flags & flags);
1114 }
1115 
1116 static inline void device_lock(struct device *dev)
1117 {
1118 	mutex_lock(&dev->mutex);
1119 }
1120 
1121 static inline int device_lock_interruptible(struct device *dev)
1122 {
1123 	return mutex_lock_interruptible(&dev->mutex);
1124 }
1125 
1126 static inline int device_trylock(struct device *dev)
1127 {
1128 	return mutex_trylock(&dev->mutex);
1129 }
1130 
1131 static inline void device_unlock(struct device *dev)
1132 {
1133 	mutex_unlock(&dev->mutex);
1134 }
1135 
1136 static inline void device_lock_assert(struct device *dev)
1137 {
1138 	lockdep_assert_held(&dev->mutex);
1139 }
1140 
1141 static inline struct device_node *dev_of_node(struct device *dev)
1142 {
1143 	if (!IS_ENABLED(CONFIG_OF))
1144 		return NULL;
1145 	return dev->of_node;
1146 }
1147 
1148 void driver_init(void);
1149 
1150 /*
1151  * High level routines for use by the bus drivers
1152  */
1153 extern int __must_check device_register(struct device *dev);
1154 extern void device_unregister(struct device *dev);
1155 extern void device_initialize(struct device *dev);
1156 extern int __must_check device_add(struct device *dev);
1157 extern void device_del(struct device *dev);
1158 extern int device_for_each_child(struct device *dev, void *data,
1159 		     int (*fn)(struct device *dev, void *data));
1160 extern int device_for_each_child_reverse(struct device *dev, void *data,
1161 		     int (*fn)(struct device *dev, void *data));
1162 extern struct device *device_find_child(struct device *dev, void *data,
1163 				int (*match)(struct device *dev, void *data));
1164 extern int device_rename(struct device *dev, const char *new_name);
1165 extern int device_move(struct device *dev, struct device *new_parent,
1166 		       enum dpm_order dpm_order);
1167 extern const char *device_get_devnode(struct device *dev,
1168 				      umode_t *mode, kuid_t *uid, kgid_t *gid,
1169 				      const char **tmp);
1170 
1171 static inline bool device_supports_offline(struct device *dev)
1172 {
1173 	return dev->bus && dev->bus->offline && dev->bus->online;
1174 }
1175 
1176 extern void lock_device_hotplug(void);
1177 extern void unlock_device_hotplug(void);
1178 extern int lock_device_hotplug_sysfs(void);
1179 extern int device_offline(struct device *dev);
1180 extern int device_online(struct device *dev);
1181 extern void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1182 extern void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1183 void device_set_of_node_from_dev(struct device *dev, const struct device *dev2);
1184 
1185 static inline int dev_num_vf(struct device *dev)
1186 {
1187 	if (dev->bus && dev->bus->num_vf)
1188 		return dev->bus->num_vf(dev);
1189 	return 0;
1190 }
1191 
1192 /*
1193  * Root device objects for grouping under /sys/devices
1194  */
1195 extern struct device *__root_device_register(const char *name,
1196 					     struct module *owner);
1197 
1198 /* This is a macro to avoid include problems with THIS_MODULE */
1199 #define root_device_register(name) \
1200 	__root_device_register(name, THIS_MODULE)
1201 
1202 extern void root_device_unregister(struct device *root);
1203 
1204 static inline void *dev_get_platdata(const struct device *dev)
1205 {
1206 	return dev->platform_data;
1207 }
1208 
1209 /*
1210  * Manual binding of a device to driver. See drivers/base/bus.c
1211  * for information on use.
1212  */
1213 extern int __must_check device_bind_driver(struct device *dev);
1214 extern void device_release_driver(struct device *dev);
1215 extern int  __must_check device_attach(struct device *dev);
1216 extern int __must_check driver_attach(struct device_driver *drv);
1217 extern void device_initial_probe(struct device *dev);
1218 extern int __must_check device_reprobe(struct device *dev);
1219 
1220 extern bool device_is_bound(struct device *dev);
1221 
1222 /*
1223  * Easy functions for dynamically creating devices on the fly
1224  */
1225 extern __printf(5, 0)
1226 struct device *device_create_vargs(struct class *cls, struct device *parent,
1227 				   dev_t devt, void *drvdata,
1228 				   const char *fmt, va_list vargs);
1229 extern __printf(5, 6)
1230 struct device *device_create(struct class *cls, struct device *parent,
1231 			     dev_t devt, void *drvdata,
1232 			     const char *fmt, ...);
1233 extern __printf(6, 7)
1234 struct device *device_create_with_groups(struct class *cls,
1235 			     struct device *parent, dev_t devt, void *drvdata,
1236 			     const struct attribute_group **groups,
1237 			     const char *fmt, ...);
1238 extern void device_destroy(struct class *cls, dev_t devt);
1239 
1240 extern int __must_check device_add_groups(struct device *dev,
1241 					const struct attribute_group **groups);
1242 extern void device_remove_groups(struct device *dev,
1243 				 const struct attribute_group **groups);
1244 
1245 static inline int __must_check device_add_group(struct device *dev,
1246 					const struct attribute_group *grp)
1247 {
1248 	const struct attribute_group *groups[] = { grp, NULL };
1249 
1250 	return device_add_groups(dev, groups);
1251 }
1252 
1253 static inline void device_remove_group(struct device *dev,
1254 				       const struct attribute_group *grp)
1255 {
1256 	const struct attribute_group *groups[] = { grp, NULL };
1257 
1258 	return device_remove_groups(dev, groups);
1259 }
1260 
1261 extern int __must_check devm_device_add_groups(struct device *dev,
1262 					const struct attribute_group **groups);
1263 extern void devm_device_remove_groups(struct device *dev,
1264 				      const struct attribute_group **groups);
1265 extern int __must_check devm_device_add_group(struct device *dev,
1266 					const struct attribute_group *grp);
1267 extern void devm_device_remove_group(struct device *dev,
1268 				     const struct attribute_group *grp);
1269 
1270 /*
1271  * Platform "fixup" functions - allow the platform to have their say
1272  * about devices and actions that the general device layer doesn't
1273  * know about.
1274  */
1275 /* Notify platform of device discovery */
1276 extern int (*platform_notify)(struct device *dev);
1277 
1278 extern int (*platform_notify_remove)(struct device *dev);
1279 
1280 
1281 /*
1282  * get_device - atomically increment the reference count for the device.
1283  *
1284  */
1285 extern struct device *get_device(struct device *dev);
1286 extern void put_device(struct device *dev);
1287 
1288 #ifdef CONFIG_DEVTMPFS
1289 extern int devtmpfs_create_node(struct device *dev);
1290 extern int devtmpfs_delete_node(struct device *dev);
1291 extern int devtmpfs_mount(const char *mntdir);
1292 #else
1293 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
1294 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
1295 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
1296 #endif
1297 
1298 /* drivers/base/power/shutdown.c */
1299 extern void device_shutdown(void);
1300 
1301 /* debugging and troubleshooting/diagnostic helpers. */
1302 extern const char *dev_driver_string(const struct device *dev);
1303 
1304 /* Device links interface. */
1305 struct device_link *device_link_add(struct device *consumer,
1306 				    struct device *supplier, u32 flags);
1307 void device_link_del(struct device_link *link);
1308 
1309 #ifdef CONFIG_PRINTK
1310 
1311 extern __printf(3, 0)
1312 int dev_vprintk_emit(int level, const struct device *dev,
1313 		     const char *fmt, va_list args);
1314 extern __printf(3, 4)
1315 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...);
1316 
1317 extern __printf(3, 4)
1318 void dev_printk(const char *level, const struct device *dev,
1319 		const char *fmt, ...);
1320 extern __printf(2, 3)
1321 void dev_emerg(const struct device *dev, const char *fmt, ...);
1322 extern __printf(2, 3)
1323 void dev_alert(const struct device *dev, const char *fmt, ...);
1324 extern __printf(2, 3)
1325 void dev_crit(const struct device *dev, const char *fmt, ...);
1326 extern __printf(2, 3)
1327 void dev_err(const struct device *dev, const char *fmt, ...);
1328 extern __printf(2, 3)
1329 void dev_warn(const struct device *dev, const char *fmt, ...);
1330 extern __printf(2, 3)
1331 void dev_notice(const struct device *dev, const char *fmt, ...);
1332 extern __printf(2, 3)
1333 void _dev_info(const struct device *dev, const char *fmt, ...);
1334 
1335 #else
1336 
1337 static inline __printf(3, 0)
1338 int dev_vprintk_emit(int level, const struct device *dev,
1339 		     const char *fmt, va_list args)
1340 { return 0; }
1341 static inline __printf(3, 4)
1342 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
1343 { return 0; }
1344 
1345 static inline void __dev_printk(const char *level, const struct device *dev,
1346 				struct va_format *vaf)
1347 {}
1348 static inline __printf(3, 4)
1349 void dev_printk(const char *level, const struct device *dev,
1350 		const char *fmt, ...)
1351 {}
1352 
1353 static inline __printf(2, 3)
1354 void dev_emerg(const struct device *dev, const char *fmt, ...)
1355 {}
1356 static inline __printf(2, 3)
1357 void dev_crit(const struct device *dev, const char *fmt, ...)
1358 {}
1359 static inline __printf(2, 3)
1360 void dev_alert(const struct device *dev, const char *fmt, ...)
1361 {}
1362 static inline __printf(2, 3)
1363 void dev_err(const struct device *dev, const char *fmt, ...)
1364 {}
1365 static inline __printf(2, 3)
1366 void dev_warn(const struct device *dev, const char *fmt, ...)
1367 {}
1368 static inline __printf(2, 3)
1369 void dev_notice(const struct device *dev, const char *fmt, ...)
1370 {}
1371 static inline __printf(2, 3)
1372 void _dev_info(const struct device *dev, const char *fmt, ...)
1373 {}
1374 
1375 #endif
1376 
1377 /*
1378  * Stupid hackaround for existing uses of non-printk uses dev_info
1379  *
1380  * Note that the definition of dev_info below is actually _dev_info
1381  * and a macro is used to avoid redefining dev_info
1382  */
1383 
1384 #define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)
1385 
1386 #if defined(CONFIG_DYNAMIC_DEBUG)
1387 #define dev_dbg(dev, format, ...)		     \
1388 do {						     \
1389 	dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
1390 } while (0)
1391 #elif defined(DEBUG)
1392 #define dev_dbg(dev, format, arg...)		\
1393 	dev_printk(KERN_DEBUG, dev, format, ##arg)
1394 #else
1395 #define dev_dbg(dev, format, arg...)				\
1396 ({								\
1397 	if (0)							\
1398 		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
1399 })
1400 #endif
1401 
1402 #ifdef CONFIG_PRINTK
1403 #define dev_level_once(dev_level, dev, fmt, ...)			\
1404 do {									\
1405 	static bool __print_once __read_mostly;				\
1406 									\
1407 	if (!__print_once) {						\
1408 		__print_once = true;					\
1409 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1410 	}								\
1411 } while (0)
1412 #else
1413 #define dev_level_once(dev_level, dev, fmt, ...)			\
1414 do {									\
1415 	if (0)								\
1416 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1417 } while (0)
1418 #endif
1419 
1420 #define dev_emerg_once(dev, fmt, ...)					\
1421 	dev_level_once(dev_emerg, dev, fmt, ##__VA_ARGS__)
1422 #define dev_alert_once(dev, fmt, ...)					\
1423 	dev_level_once(dev_alert, dev, fmt, ##__VA_ARGS__)
1424 #define dev_crit_once(dev, fmt, ...)					\
1425 	dev_level_once(dev_crit, dev, fmt, ##__VA_ARGS__)
1426 #define dev_err_once(dev, fmt, ...)					\
1427 	dev_level_once(dev_err, dev, fmt, ##__VA_ARGS__)
1428 #define dev_warn_once(dev, fmt, ...)					\
1429 	dev_level_once(dev_warn, dev, fmt, ##__VA_ARGS__)
1430 #define dev_notice_once(dev, fmt, ...)					\
1431 	dev_level_once(dev_notice, dev, fmt, ##__VA_ARGS__)
1432 #define dev_info_once(dev, fmt, ...)					\
1433 	dev_level_once(dev_info, dev, fmt, ##__VA_ARGS__)
1434 #define dev_dbg_once(dev, fmt, ...)					\
1435 	dev_level_once(dev_dbg, dev, fmt, ##__VA_ARGS__)
1436 
1437 #define dev_level_ratelimited(dev_level, dev, fmt, ...)			\
1438 do {									\
1439 	static DEFINE_RATELIMIT_STATE(_rs,				\
1440 				      DEFAULT_RATELIMIT_INTERVAL,	\
1441 				      DEFAULT_RATELIMIT_BURST);		\
1442 	if (__ratelimit(&_rs))						\
1443 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1444 } while (0)
1445 
1446 #define dev_emerg_ratelimited(dev, fmt, ...)				\
1447 	dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__)
1448 #define dev_alert_ratelimited(dev, fmt, ...)				\
1449 	dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__)
1450 #define dev_crit_ratelimited(dev, fmt, ...)				\
1451 	dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__)
1452 #define dev_err_ratelimited(dev, fmt, ...)				\
1453 	dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__)
1454 #define dev_warn_ratelimited(dev, fmt, ...)				\
1455 	dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__)
1456 #define dev_notice_ratelimited(dev, fmt, ...)				\
1457 	dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__)
1458 #define dev_info_ratelimited(dev, fmt, ...)				\
1459 	dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__)
1460 #if defined(CONFIG_DYNAMIC_DEBUG)
1461 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
1462 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1463 do {									\
1464 	static DEFINE_RATELIMIT_STATE(_rs,				\
1465 				      DEFAULT_RATELIMIT_INTERVAL,	\
1466 				      DEFAULT_RATELIMIT_BURST);		\
1467 	DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);			\
1468 	if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) &&	\
1469 	    __ratelimit(&_rs))						\
1470 		__dynamic_dev_dbg(&descriptor, dev, fmt,		\
1471 				  ##__VA_ARGS__);			\
1472 } while (0)
1473 #elif defined(DEBUG)
1474 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1475 do {									\
1476 	static DEFINE_RATELIMIT_STATE(_rs,				\
1477 				      DEFAULT_RATELIMIT_INTERVAL,	\
1478 				      DEFAULT_RATELIMIT_BURST);		\
1479 	if (__ratelimit(&_rs))						\
1480 		dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__);	\
1481 } while (0)
1482 #else
1483 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1484 do {									\
1485 	if (0)								\
1486 		dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__);	\
1487 } while (0)
1488 #endif
1489 
1490 #ifdef VERBOSE_DEBUG
1491 #define dev_vdbg	dev_dbg
1492 #else
1493 #define dev_vdbg(dev, format, arg...)				\
1494 ({								\
1495 	if (0)							\
1496 		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
1497 })
1498 #endif
1499 
1500 /*
1501  * dev_WARN*() acts like dev_printk(), but with the key difference of
1502  * using WARN/WARN_ONCE to include file/line information and a backtrace.
1503  */
1504 #define dev_WARN(dev, format, arg...) \
1505 	WARN(1, "%s %s: " format, dev_driver_string(dev), dev_name(dev), ## arg);
1506 
1507 #define dev_WARN_ONCE(dev, condition, format, arg...) \
1508 	WARN_ONCE(condition, "%s %s: " format, \
1509 			dev_driver_string(dev), dev_name(dev), ## arg)
1510 
1511 /* Create alias, so I can be autoloaded. */
1512 #define MODULE_ALIAS_CHARDEV(major,minor) \
1513 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1514 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1515 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
1516 
1517 #ifdef CONFIG_SYSFS_DEPRECATED
1518 extern long sysfs_deprecated;
1519 #else
1520 #define sysfs_deprecated 0
1521 #endif
1522 
1523 /**
1524  * module_driver() - Helper macro for drivers that don't do anything
1525  * special in module init/exit. This eliminates a lot of boilerplate.
1526  * Each module may only use this macro once, and calling it replaces
1527  * module_init() and module_exit().
1528  *
1529  * @__driver: driver name
1530  * @__register: register function for this driver type
1531  * @__unregister: unregister function for this driver type
1532  * @...: Additional arguments to be passed to __register and __unregister.
1533  *
1534  * Use this macro to construct bus specific macros for registering
1535  * drivers, and do not use it on its own.
1536  */
1537 #define module_driver(__driver, __register, __unregister, ...) \
1538 static int __init __driver##_init(void) \
1539 { \
1540 	return __register(&(__driver) , ##__VA_ARGS__); \
1541 } \
1542 module_init(__driver##_init); \
1543 static void __exit __driver##_exit(void) \
1544 { \
1545 	__unregister(&(__driver) , ##__VA_ARGS__); \
1546 } \
1547 module_exit(__driver##_exit);
1548 
1549 /**
1550  * builtin_driver() - Helper macro for drivers that don't do anything
1551  * special in init and have no exit. This eliminates some boilerplate.
1552  * Each driver may only use this macro once, and calling it replaces
1553  * device_initcall (or in some cases, the legacy __initcall).  This is
1554  * meant to be a direct parallel of module_driver() above but without
1555  * the __exit stuff that is not used for builtin cases.
1556  *
1557  * @__driver: driver name
1558  * @__register: register function for this driver type
1559  * @...: Additional arguments to be passed to __register
1560  *
1561  * Use this macro to construct bus specific macros for registering
1562  * drivers, and do not use it on its own.
1563  */
1564 #define builtin_driver(__driver, __register, ...) \
1565 static int __init __driver##_init(void) \
1566 { \
1567 	return __register(&(__driver) , ##__VA_ARGS__); \
1568 } \
1569 device_initcall(__driver##_init);
1570 
1571 #endif /* _DEVICE_H_ */
1572