xref: /linux-6.15/include/linux/device.h (revision a1cd4e43)
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 <linux/overflow.h>
29 #include <asm/device.h>
30 
31 struct device;
32 struct device_private;
33 struct device_driver;
34 struct driver_private;
35 struct module;
36 struct class;
37 struct subsys_private;
38 struct bus_type;
39 struct device_node;
40 struct fwnode_handle;
41 struct iommu_ops;
42 struct iommu_group;
43 struct iommu_fwspec;
44 struct dev_pin_info;
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_RW(_name) \
53 	struct bus_attribute bus_attr_##_name = __ATTR_RW(_name)
54 #define BUS_ATTR_RO(_name) \
55 	struct bus_attribute bus_attr_##_name = __ATTR_RO(_name)
56 #define BUS_ATTR_WO(_name) \
57 	struct bus_attribute bus_attr_##_name = __ATTR_WO(_name)
58 
59 extern int __must_check bus_create_file(struct bus_type *,
60 					struct bus_attribute *);
61 extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
62 
63 /**
64  * struct bus_type - The bus type of the device
65  *
66  * @name:	The name of the bus.
67  * @dev_name:	Used for subsystems to enumerate devices like ("foo%u", dev->id).
68  * @dev_root:	Default device to use as the parent.
69  * @bus_groups:	Default attributes of the bus.
70  * @dev_groups:	Default attributes of the devices on the bus.
71  * @drv_groups: Default attributes of the device drivers on the bus.
72  * @match:	Called, perhaps multiple times, whenever a new device or driver
73  *		is added for this bus. It should return a positive value if the
74  *		given device can be handled by the given driver and zero
75  *		otherwise. It may also return error code if determining that
76  *		the driver supports the device is not possible. In case of
77  *		-EPROBE_DEFER it will queue the device for deferred probing.
78  * @uevent:	Called when a device is added, removed, or a few other things
79  *		that generate uevents to add the environment variables.
80  * @probe:	Called when a new device or driver add to this bus, and callback
81  *		the specific driver's probe to initial the matched device.
82  * @remove:	Called when a device removed from this bus.
83  * @shutdown:	Called at shut-down time to quiesce the device.
84  *
85  * @online:	Called to put the device back online (after offlining it).
86  * @offline:	Called to put the device offline for hot-removal. May fail.
87  *
88  * @suspend:	Called when a device on this bus wants to go to sleep mode.
89  * @resume:	Called to bring a device on this bus out of sleep mode.
90  * @num_vf:	Called to find out how many virtual functions a device on this
91  *		bus supports.
92  * @dma_configure:	Called to setup DMA configuration on a device on
93  *			this bus.
94  * @pm:		Power management operations of this bus, callback the specific
95  *		device driver's pm-ops.
96  * @iommu_ops:  IOMMU specific operations for this bus, used to attach IOMMU
97  *              driver implementations to a bus and allow the driver to do
98  *              bus-specific setup
99  * @p:		The private data of the driver core, only the driver core can
100  *		touch this.
101  * @lock_key:	Lock class key for use by the lock validator
102  * @need_parent_lock:	When probing or removing a device on this bus, the
103  *			device core should lock the device's parent.
104  *
105  * A bus is a channel between the processor and one or more devices. For the
106  * purposes of the device model, all devices are connected via a bus, even if
107  * it is an internal, virtual, "platform" bus. Buses can plug into each other.
108  * A USB controller is usually a PCI device, for example. The device model
109  * represents the actual connections between buses and the devices they control.
110  * A bus is represented by the bus_type structure. It contains the name, the
111  * default attributes, the bus' methods, PM operations, and the driver core's
112  * private data.
113  */
114 struct bus_type {
115 	const char		*name;
116 	const char		*dev_name;
117 	struct device		*dev_root;
118 	const struct attribute_group **bus_groups;
119 	const struct attribute_group **dev_groups;
120 	const struct attribute_group **drv_groups;
121 
122 	int (*match)(struct device *dev, struct device_driver *drv);
123 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
124 	int (*probe)(struct device *dev);
125 	int (*remove)(struct device *dev);
126 	void (*shutdown)(struct device *dev);
127 
128 	int (*online)(struct device *dev);
129 	int (*offline)(struct device *dev);
130 
131 	int (*suspend)(struct device *dev, pm_message_t state);
132 	int (*resume)(struct device *dev);
133 
134 	int (*num_vf)(struct device *dev);
135 
136 	int (*dma_configure)(struct device *dev);
137 
138 	const struct dev_pm_ops *pm;
139 
140 	const struct iommu_ops *iommu_ops;
141 
142 	struct subsys_private *p;
143 	struct lock_class_key lock_key;
144 
145 	bool need_parent_lock;
146 };
147 
148 extern int __must_check bus_register(struct bus_type *bus);
149 
150 extern void bus_unregister(struct bus_type *bus);
151 
152 extern int __must_check bus_rescan_devices(struct bus_type *bus);
153 
154 /* iterator helpers for buses */
155 struct subsys_dev_iter {
156 	struct klist_iter		ki;
157 	const struct device_type	*type;
158 };
159 void subsys_dev_iter_init(struct subsys_dev_iter *iter,
160 			 struct bus_type *subsys,
161 			 struct device *start,
162 			 const struct device_type *type);
163 struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter);
164 void subsys_dev_iter_exit(struct subsys_dev_iter *iter);
165 
166 int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
167 		     int (*fn)(struct device *dev, void *data));
168 struct device *bus_find_device(struct bus_type *bus, struct device *start,
169 			       void *data,
170 			       int (*match)(struct device *dev, void *data));
171 struct device *bus_find_device_by_name(struct bus_type *bus,
172 				       struct device *start,
173 				       const char *name);
174 struct device *subsys_find_device_by_id(struct bus_type *bus, unsigned int id,
175 					struct device *hint);
176 int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
177 		     void *data, int (*fn)(struct device_driver *, void *));
178 void bus_sort_breadthfirst(struct bus_type *bus,
179 			   int (*compare)(const struct device *a,
180 					  const struct device *b));
181 /*
182  * Bus notifiers: Get notified of addition/removal of devices
183  * and binding/unbinding of drivers to devices.
184  * In the long run, it should be a replacement for the platform
185  * notify hooks.
186  */
187 struct notifier_block;
188 
189 extern int bus_register_notifier(struct bus_type *bus,
190 				 struct notifier_block *nb);
191 extern int bus_unregister_notifier(struct bus_type *bus,
192 				   struct notifier_block *nb);
193 
194 /* All 4 notifers below get called with the target struct device *
195  * as an argument. Note that those functions are likely to be called
196  * with the device lock held in the core, so be careful.
197  */
198 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
199 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device to be removed */
200 #define BUS_NOTIFY_REMOVED_DEVICE	0x00000003 /* device removed */
201 #define BUS_NOTIFY_BIND_DRIVER		0x00000004 /* driver about to be
202 						      bound */
203 #define BUS_NOTIFY_BOUND_DRIVER		0x00000005 /* driver bound to device */
204 #define BUS_NOTIFY_UNBIND_DRIVER	0x00000006 /* driver about to be
205 						      unbound */
206 #define BUS_NOTIFY_UNBOUND_DRIVER	0x00000007 /* driver is unbound
207 						      from the device */
208 #define BUS_NOTIFY_DRIVER_NOT_BOUND	0x00000008 /* driver fails to be bound */
209 
210 extern struct kset *bus_get_kset(struct bus_type *bus);
211 extern struct klist *bus_get_device_klist(struct bus_type *bus);
212 
213 /**
214  * enum probe_type - device driver probe type to try
215  *	Device drivers may opt in for special handling of their
216  *	respective probe routines. This tells the core what to
217  *	expect and prefer.
218  *
219  * @PROBE_DEFAULT_STRATEGY: Used by drivers that work equally well
220  *	whether probed synchronously or asynchronously.
221  * @PROBE_PREFER_ASYNCHRONOUS: Drivers for "slow" devices which
222  *	probing order is not essential for booting the system may
223  *	opt into executing their probes asynchronously.
224  * @PROBE_FORCE_SYNCHRONOUS: Use this to annotate drivers that need
225  *	their probe routines to run synchronously with driver and
226  *	device registration (with the exception of -EPROBE_DEFER
227  *	handling - re-probing always ends up being done asynchronously).
228  *
229  * Note that the end goal is to switch the kernel to use asynchronous
230  * probing by default, so annotating drivers with
231  * %PROBE_PREFER_ASYNCHRONOUS is a temporary measure that allows us
232  * to speed up boot process while we are validating the rest of the
233  * drivers.
234  */
235 enum probe_type {
236 	PROBE_DEFAULT_STRATEGY,
237 	PROBE_PREFER_ASYNCHRONOUS,
238 	PROBE_FORCE_SYNCHRONOUS,
239 };
240 
241 /**
242  * struct device_driver - The basic device driver structure
243  * @name:	Name of the device driver.
244  * @bus:	The bus which the device of this driver belongs to.
245  * @owner:	The module owner.
246  * @mod_name:	Used for built-in modules.
247  * @suppress_bind_attrs: Disables bind/unbind via sysfs.
248  * @probe_type:	Type of the probe (synchronous or asynchronous) to use.
249  * @of_match_table: The open firmware table.
250  * @acpi_match_table: The ACPI match table.
251  * @probe:	Called to query the existence of a specific device,
252  *		whether this driver can work with it, and bind the driver
253  *		to a specific device.
254  * @remove:	Called when the device is removed from the system to
255  *		unbind a device from this driver.
256  * @shutdown:	Called at shut-down time to quiesce the device.
257  * @suspend:	Called to put the device to sleep mode. Usually to a
258  *		low power state.
259  * @resume:	Called to bring a device from sleep mode.
260  * @groups:	Default attributes that get created by the driver core
261  *		automatically.
262  * @pm:		Power management operations of the device which matched
263  *		this driver.
264  * @coredump:	Called when sysfs entry is written to. The device driver
265  *		is expected to call the dev_coredump API resulting in a
266  *		uevent.
267  * @p:		Driver core's private data, no one other than the driver
268  *		core can touch this.
269  *
270  * The device driver-model tracks all of the drivers known to the system.
271  * The main reason for this tracking is to enable the driver core to match
272  * up drivers with new devices. Once drivers are known objects within the
273  * system, however, a number of other things become possible. Device drivers
274  * can export information and configuration variables that are independent
275  * of any specific device.
276  */
277 struct device_driver {
278 	const char		*name;
279 	struct bus_type		*bus;
280 
281 	struct module		*owner;
282 	const char		*mod_name;	/* used for built-in modules */
283 
284 	bool suppress_bind_attrs;	/* disables bind/unbind via sysfs */
285 	enum probe_type probe_type;
286 
287 	const struct of_device_id	*of_match_table;
288 	const struct acpi_device_id	*acpi_match_table;
289 
290 	int (*probe) (struct device *dev);
291 	int (*remove) (struct device *dev);
292 	void (*shutdown) (struct device *dev);
293 	int (*suspend) (struct device *dev, pm_message_t state);
294 	int (*resume) (struct device *dev);
295 	const struct attribute_group **groups;
296 
297 	const struct dev_pm_ops *pm;
298 	void (*coredump) (struct device *dev);
299 
300 	struct driver_private *p;
301 };
302 
303 
304 extern int __must_check driver_register(struct device_driver *drv);
305 extern void driver_unregister(struct device_driver *drv);
306 
307 extern struct device_driver *driver_find(const char *name,
308 					 struct bus_type *bus);
309 extern int driver_probe_done(void);
310 extern void wait_for_device_probe(void);
311 
312 /* sysfs interface for exporting driver attributes */
313 
314 struct driver_attribute {
315 	struct attribute attr;
316 	ssize_t (*show)(struct device_driver *driver, char *buf);
317 	ssize_t (*store)(struct device_driver *driver, const char *buf,
318 			 size_t count);
319 };
320 
321 #define DRIVER_ATTR_RW(_name) \
322 	struct driver_attribute driver_attr_##_name = __ATTR_RW(_name)
323 #define DRIVER_ATTR_RO(_name) \
324 	struct driver_attribute driver_attr_##_name = __ATTR_RO(_name)
325 #define DRIVER_ATTR_WO(_name) \
326 	struct driver_attribute driver_attr_##_name = __ATTR_WO(_name)
327 
328 extern int __must_check driver_create_file(struct device_driver *driver,
329 					const struct driver_attribute *attr);
330 extern void driver_remove_file(struct device_driver *driver,
331 			       const struct driver_attribute *attr);
332 
333 extern int __must_check driver_for_each_device(struct device_driver *drv,
334 					       struct device *start,
335 					       void *data,
336 					       int (*fn)(struct device *dev,
337 							 void *));
338 struct device *driver_find_device(struct device_driver *drv,
339 				  struct device *start, void *data,
340 				  int (*match)(struct device *dev, void *data));
341 
342 void driver_deferred_probe_add(struct device *dev);
343 int driver_deferred_probe_check_state(struct device *dev);
344 
345 /**
346  * struct subsys_interface - interfaces to device functions
347  * @name:       name of the device function
348  * @subsys:     subsytem of the devices to attach to
349  * @node:       the list of functions registered at the subsystem
350  * @add_dev:    device hookup to device function handler
351  * @remove_dev: device hookup to device function handler
352  *
353  * Simple interfaces attached to a subsystem. Multiple interfaces can
354  * attach to a subsystem and its devices. Unlike drivers, they do not
355  * exclusively claim or control devices. Interfaces usually represent
356  * a specific functionality of a subsystem/class of devices.
357  */
358 struct subsys_interface {
359 	const char *name;
360 	struct bus_type *subsys;
361 	struct list_head node;
362 	int (*add_dev)(struct device *dev, struct subsys_interface *sif);
363 	void (*remove_dev)(struct device *dev, struct subsys_interface *sif);
364 };
365 
366 int subsys_interface_register(struct subsys_interface *sif);
367 void subsys_interface_unregister(struct subsys_interface *sif);
368 
369 int subsys_system_register(struct bus_type *subsys,
370 			   const struct attribute_group **groups);
371 int subsys_virtual_register(struct bus_type *subsys,
372 			    const struct attribute_group **groups);
373 
374 /**
375  * struct class - device classes
376  * @name:	Name of the class.
377  * @owner:	The module owner.
378  * @class_groups: Default attributes of this class.
379  * @dev_groups:	Default attributes of the devices that belong to the class.
380  * @dev_kobj:	The kobject that represents this class and links it into the hierarchy.
381  * @dev_uevent:	Called when a device is added, removed from this class, or a
382  *		few other things that generate uevents to add the environment
383  *		variables.
384  * @devnode:	Callback to provide the devtmpfs.
385  * @class_release: Called to release this class.
386  * @dev_release: Called to release the device.
387  * @shutdown_pre: Called at shut-down time before driver shutdown.
388  * @ns_type:	Callbacks so sysfs can detemine namespaces.
389  * @namespace:	Namespace of the device belongs to this class.
390  * @get_ownership: Allows class to specify uid/gid of the sysfs directories
391  *		for the devices belonging to the class. Usually tied to
392  *		device's namespace.
393  * @pm:		The default device power management operations of this class.
394  * @p:		The private data of the driver core, no one other than the
395  *		driver core can touch this.
396  *
397  * A class is a higher-level view of a device that abstracts out low-level
398  * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
399  * at the class level, they are all simply disks. Classes allow user space
400  * to work with devices based on what they do, rather than how they are
401  * connected or how they work.
402  */
403 struct class {
404 	const char		*name;
405 	struct module		*owner;
406 
407 	const struct attribute_group	**class_groups;
408 	const struct attribute_group	**dev_groups;
409 	struct kobject			*dev_kobj;
410 
411 	int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
412 	char *(*devnode)(struct device *dev, umode_t *mode);
413 
414 	void (*class_release)(struct class *class);
415 	void (*dev_release)(struct device *dev);
416 
417 	int (*shutdown_pre)(struct device *dev);
418 
419 	const struct kobj_ns_type_operations *ns_type;
420 	const void *(*namespace)(struct device *dev);
421 
422 	void (*get_ownership)(struct device *dev, kuid_t *uid, kgid_t *gid);
423 
424 	const struct dev_pm_ops *pm;
425 
426 	struct subsys_private *p;
427 };
428 
429 struct class_dev_iter {
430 	struct klist_iter		ki;
431 	const struct device_type	*type;
432 };
433 
434 extern struct kobject *sysfs_dev_block_kobj;
435 extern struct kobject *sysfs_dev_char_kobj;
436 extern int __must_check __class_register(struct class *class,
437 					 struct lock_class_key *key);
438 extern void class_unregister(struct class *class);
439 
440 /* This is a #define to keep the compiler from merging different
441  * instances of the __key variable */
442 #define class_register(class)			\
443 ({						\
444 	static struct lock_class_key __key;	\
445 	__class_register(class, &__key);	\
446 })
447 
448 struct class_compat;
449 struct class_compat *class_compat_register(const char *name);
450 void class_compat_unregister(struct class_compat *cls);
451 int class_compat_create_link(struct class_compat *cls, struct device *dev,
452 			     struct device *device_link);
453 void class_compat_remove_link(struct class_compat *cls, struct device *dev,
454 			      struct device *device_link);
455 
456 extern void class_dev_iter_init(struct class_dev_iter *iter,
457 				struct class *class,
458 				struct device *start,
459 				const struct device_type *type);
460 extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
461 extern void class_dev_iter_exit(struct class_dev_iter *iter);
462 
463 extern int class_for_each_device(struct class *class, struct device *start,
464 				 void *data,
465 				 int (*fn)(struct device *dev, void *data));
466 extern struct device *class_find_device(struct class *class,
467 					struct device *start, const void *data,
468 					int (*match)(struct device *, const void *));
469 
470 struct class_attribute {
471 	struct attribute attr;
472 	ssize_t (*show)(struct class *class, struct class_attribute *attr,
473 			char *buf);
474 	ssize_t (*store)(struct class *class, struct class_attribute *attr,
475 			const char *buf, size_t count);
476 };
477 
478 #define CLASS_ATTR_RW(_name) \
479 	struct class_attribute class_attr_##_name = __ATTR_RW(_name)
480 #define CLASS_ATTR_RO(_name) \
481 	struct class_attribute class_attr_##_name = __ATTR_RO(_name)
482 #define CLASS_ATTR_WO(_name) \
483 	struct class_attribute class_attr_##_name = __ATTR_WO(_name)
484 
485 extern int __must_check class_create_file_ns(struct class *class,
486 					     const struct class_attribute *attr,
487 					     const void *ns);
488 extern void class_remove_file_ns(struct class *class,
489 				 const struct class_attribute *attr,
490 				 const void *ns);
491 
492 static inline int __must_check class_create_file(struct class *class,
493 					const struct class_attribute *attr)
494 {
495 	return class_create_file_ns(class, attr, NULL);
496 }
497 
498 static inline void class_remove_file(struct class *class,
499 				     const struct class_attribute *attr)
500 {
501 	return class_remove_file_ns(class, attr, NULL);
502 }
503 
504 /* Simple class attribute that is just a static string */
505 struct class_attribute_string {
506 	struct class_attribute attr;
507 	char *str;
508 };
509 
510 /* Currently read-only only */
511 #define _CLASS_ATTR_STRING(_name, _mode, _str) \
512 	{ __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
513 #define CLASS_ATTR_STRING(_name, _mode, _str) \
514 	struct class_attribute_string class_attr_##_name = \
515 		_CLASS_ATTR_STRING(_name, _mode, _str)
516 
517 extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
518                         char *buf);
519 
520 struct class_interface {
521 	struct list_head	node;
522 	struct class		*class;
523 
524 	int (*add_dev)		(struct device *, struct class_interface *);
525 	void (*remove_dev)	(struct device *, struct class_interface *);
526 };
527 
528 extern int __must_check class_interface_register(struct class_interface *);
529 extern void class_interface_unregister(struct class_interface *);
530 
531 extern struct class * __must_check __class_create(struct module *owner,
532 						  const char *name,
533 						  struct lock_class_key *key);
534 extern void class_destroy(struct class *cls);
535 
536 /* This is a #define to keep the compiler from merging different
537  * instances of the __key variable */
538 #define class_create(owner, name)		\
539 ({						\
540 	static struct lock_class_key __key;	\
541 	__class_create(owner, name, &__key);	\
542 })
543 
544 /*
545  * The type of device, "struct device" is embedded in. A class
546  * or bus can contain devices of different types
547  * like "partitions" and "disks", "mouse" and "event".
548  * This identifies the device type and carries type-specific
549  * information, equivalent to the kobj_type of a kobject.
550  * If "name" is specified, the uevent will contain it in
551  * the DEVTYPE variable.
552  */
553 struct device_type {
554 	const char *name;
555 	const struct attribute_group **groups;
556 	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
557 	char *(*devnode)(struct device *dev, umode_t *mode,
558 			 kuid_t *uid, kgid_t *gid);
559 	void (*release)(struct device *dev);
560 
561 	const struct dev_pm_ops *pm;
562 };
563 
564 /* interface for exporting device attributes */
565 struct device_attribute {
566 	struct attribute	attr;
567 	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
568 			char *buf);
569 	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
570 			 const char *buf, size_t count);
571 };
572 
573 struct dev_ext_attribute {
574 	struct device_attribute attr;
575 	void *var;
576 };
577 
578 ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
579 			  char *buf);
580 ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
581 			   const char *buf, size_t count);
582 ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
583 			char *buf);
584 ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
585 			 const char *buf, size_t count);
586 ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
587 			char *buf);
588 ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
589 			 const char *buf, size_t count);
590 
591 #define DEVICE_ATTR(_name, _mode, _show, _store) \
592 	struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
593 #define DEVICE_ATTR_PREALLOC(_name, _mode, _show, _store) \
594 	struct device_attribute dev_attr_##_name = \
595 		__ATTR_PREALLOC(_name, _mode, _show, _store)
596 #define DEVICE_ATTR_RW(_name) \
597 	struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
598 #define DEVICE_ATTR_RO(_name) \
599 	struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
600 #define DEVICE_ATTR_WO(_name) \
601 	struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
602 #define DEVICE_ULONG_ATTR(_name, _mode, _var) \
603 	struct dev_ext_attribute dev_attr_##_name = \
604 		{ __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
605 #define DEVICE_INT_ATTR(_name, _mode, _var) \
606 	struct dev_ext_attribute dev_attr_##_name = \
607 		{ __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
608 #define DEVICE_BOOL_ATTR(_name, _mode, _var) \
609 	struct dev_ext_attribute dev_attr_##_name = \
610 		{ __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
611 #define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
612 	struct device_attribute dev_attr_##_name =		\
613 		__ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
614 
615 extern int device_create_file(struct device *device,
616 			      const struct device_attribute *entry);
617 extern void device_remove_file(struct device *dev,
618 			       const struct device_attribute *attr);
619 extern bool device_remove_file_self(struct device *dev,
620 				    const struct device_attribute *attr);
621 extern int __must_check device_create_bin_file(struct device *dev,
622 					const struct bin_attribute *attr);
623 extern void device_remove_bin_file(struct device *dev,
624 				   const struct bin_attribute *attr);
625 
626 /* device resource management */
627 typedef void (*dr_release_t)(struct device *dev, void *res);
628 typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
629 
630 #ifdef CONFIG_DEBUG_DEVRES
631 extern void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
632 				 int nid, const char *name) __malloc;
633 #define devres_alloc(release, size, gfp) \
634 	__devres_alloc_node(release, size, gfp, NUMA_NO_NODE, #release)
635 #define devres_alloc_node(release, size, gfp, nid) \
636 	__devres_alloc_node(release, size, gfp, nid, #release)
637 #else
638 extern void *devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp,
639 			       int nid) __malloc;
640 static inline void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp)
641 {
642 	return devres_alloc_node(release, size, gfp, NUMA_NO_NODE);
643 }
644 #endif
645 
646 extern void devres_for_each_res(struct device *dev, dr_release_t release,
647 				dr_match_t match, void *match_data,
648 				void (*fn)(struct device *, void *, void *),
649 				void *data);
650 extern void devres_free(void *res);
651 extern void devres_add(struct device *dev, void *res);
652 extern void *devres_find(struct device *dev, dr_release_t release,
653 			 dr_match_t match, void *match_data);
654 extern void *devres_get(struct device *dev, void *new_res,
655 			dr_match_t match, void *match_data);
656 extern void *devres_remove(struct device *dev, dr_release_t release,
657 			   dr_match_t match, void *match_data);
658 extern int devres_destroy(struct device *dev, dr_release_t release,
659 			  dr_match_t match, void *match_data);
660 extern int devres_release(struct device *dev, dr_release_t release,
661 			  dr_match_t match, void *match_data);
662 
663 /* devres group */
664 extern void * __must_check devres_open_group(struct device *dev, void *id,
665 					     gfp_t gfp);
666 extern void devres_close_group(struct device *dev, void *id);
667 extern void devres_remove_group(struct device *dev, void *id);
668 extern int devres_release_group(struct device *dev, void *id);
669 
670 /* managed devm_k.alloc/kfree for device drivers */
671 extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __malloc;
672 extern __printf(3, 0)
673 char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt,
674 		      va_list ap) __malloc;
675 extern __printf(3, 4)
676 char *devm_kasprintf(struct device *dev, gfp_t gfp, const char *fmt, ...) __malloc;
677 static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
678 {
679 	return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
680 }
681 static inline void *devm_kmalloc_array(struct device *dev,
682 				       size_t n, size_t size, gfp_t flags)
683 {
684 	size_t bytes;
685 
686 	if (unlikely(check_mul_overflow(n, size, &bytes)))
687 		return NULL;
688 
689 	return devm_kmalloc(dev, bytes, flags);
690 }
691 static inline void *devm_kcalloc(struct device *dev,
692 				 size_t n, size_t size, gfp_t flags)
693 {
694 	return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
695 }
696 extern void devm_kfree(struct device *dev, const void *p);
697 extern char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
698 extern const char *devm_kstrdup_const(struct device *dev,
699 				      const char *s, gfp_t gfp);
700 extern void *devm_kmemdup(struct device *dev, const void *src, size_t len,
701 			  gfp_t gfp);
702 
703 extern unsigned long devm_get_free_pages(struct device *dev,
704 					 gfp_t gfp_mask, unsigned int order);
705 extern void devm_free_pages(struct device *dev, unsigned long addr);
706 
707 void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
708 
709 void __iomem *devm_of_iomap(struct device *dev,
710 			    struct device_node *node, int index,
711 			    resource_size_t *size);
712 
713 /* allows to add/remove a custom action to devres stack */
714 int devm_add_action(struct device *dev, void (*action)(void *), void *data);
715 void devm_remove_action(struct device *dev, void (*action)(void *), void *data);
716 void devm_release_action(struct device *dev, void (*action)(void *), void *data);
717 
718 static inline int devm_add_action_or_reset(struct device *dev,
719 					   void (*action)(void *), void *data)
720 {
721 	int ret;
722 
723 	ret = devm_add_action(dev, action, data);
724 	if (ret)
725 		action(data);
726 
727 	return ret;
728 }
729 
730 /**
731  * devm_alloc_percpu - Resource-managed alloc_percpu
732  * @dev: Device to allocate per-cpu memory for
733  * @type: Type to allocate per-cpu memory for
734  *
735  * Managed alloc_percpu. Per-cpu memory allocated with this function is
736  * automatically freed on driver detach.
737  *
738  * RETURNS:
739  * Pointer to allocated memory on success, NULL on failure.
740  */
741 #define devm_alloc_percpu(dev, type)      \
742 	((typeof(type) __percpu *)__devm_alloc_percpu((dev), sizeof(type), \
743 						      __alignof__(type)))
744 
745 void __percpu *__devm_alloc_percpu(struct device *dev, size_t size,
746 				   size_t align);
747 void devm_free_percpu(struct device *dev, void __percpu *pdata);
748 
749 struct device_dma_parameters {
750 	/*
751 	 * a low level driver may set these to teach IOMMU code about
752 	 * sg limitations.
753 	 */
754 	unsigned int max_segment_size;
755 	unsigned long segment_boundary_mask;
756 };
757 
758 /**
759  * struct device_connection - Device Connection Descriptor
760  * @fwnode: The device node of the connected device
761  * @endpoint: The names of the two devices connected together
762  * @id: Unique identifier for the connection
763  * @list: List head, private, for internal use only
764  *
765  * NOTE: @fwnode is not used together with @endpoint. @fwnode is used when
766  * platform firmware defines the connection. When the connection is registered
767  * with device_connection_add() @endpoint is used instead.
768  */
769 struct device_connection {
770 	struct fwnode_handle	*fwnode;
771 	const char		*endpoint[2];
772 	const char		*id;
773 	struct list_head	list;
774 };
775 
776 void *device_connection_find_match(struct device *dev, const char *con_id,
777 				void *data,
778 				void *(*match)(struct device_connection *con,
779 					       int ep, void *data));
780 
781 struct device *device_connection_find(struct device *dev, const char *con_id);
782 
783 void device_connection_add(struct device_connection *con);
784 void device_connection_remove(struct device_connection *con);
785 
786 /**
787  * device_connections_add - Add multiple device connections at once
788  * @cons: Zero terminated array of device connection descriptors
789  */
790 static inline void device_connections_add(struct device_connection *cons)
791 {
792 	struct device_connection *c;
793 
794 	for (c = cons; c->endpoint[0]; c++)
795 		device_connection_add(c);
796 }
797 
798 /**
799  * device_connections_remove - Remove multiple device connections at once
800  * @cons: Zero terminated array of device connection descriptors
801  */
802 static inline void device_connections_remove(struct device_connection *cons)
803 {
804 	struct device_connection *c;
805 
806 	for (c = cons; c->endpoint[0]; c++)
807 		device_connection_remove(c);
808 }
809 
810 /**
811  * enum device_link_state - Device link states.
812  * @DL_STATE_NONE: The presence of the drivers is not being tracked.
813  * @DL_STATE_DORMANT: None of the supplier/consumer drivers is present.
814  * @DL_STATE_AVAILABLE: The supplier driver is present, but the consumer is not.
815  * @DL_STATE_CONSUMER_PROBE: The consumer is probing (supplier driver present).
816  * @DL_STATE_ACTIVE: Both the supplier and consumer drivers are present.
817  * @DL_STATE_SUPPLIER_UNBIND: The supplier driver is unbinding.
818  */
819 enum device_link_state {
820 	DL_STATE_NONE = -1,
821 	DL_STATE_DORMANT = 0,
822 	DL_STATE_AVAILABLE,
823 	DL_STATE_CONSUMER_PROBE,
824 	DL_STATE_ACTIVE,
825 	DL_STATE_SUPPLIER_UNBIND,
826 };
827 
828 /*
829  * Device link flags.
830  *
831  * STATELESS: The core won't track the presence of supplier/consumer drivers.
832  * AUTOREMOVE_CONSUMER: Remove the link automatically on consumer driver unbind.
833  * PM_RUNTIME: If set, the runtime PM framework will use this link.
834  * RPM_ACTIVE: Run pm_runtime_get_sync() on the supplier during link creation.
835  * AUTOREMOVE_SUPPLIER: Remove the link automatically on supplier driver unbind.
836  * AUTOPROBE_CONSUMER: Probe consumer driver automatically after supplier binds.
837  */
838 #define DL_FLAG_STATELESS		BIT(0)
839 #define DL_FLAG_AUTOREMOVE_CONSUMER	BIT(1)
840 #define DL_FLAG_PM_RUNTIME		BIT(2)
841 #define DL_FLAG_RPM_ACTIVE		BIT(3)
842 #define DL_FLAG_AUTOREMOVE_SUPPLIER	BIT(4)
843 #define DL_FLAG_AUTOPROBE_CONSUMER	BIT(5)
844 
845 /**
846  * struct device_link - Device link representation.
847  * @supplier: The device on the supplier end of the link.
848  * @s_node: Hook to the supplier device's list of links to consumers.
849  * @consumer: The device on the consumer end of the link.
850  * @c_node: Hook to the consumer device's list of links to suppliers.
851  * @status: The state of the link (with respect to the presence of drivers).
852  * @flags: Link flags.
853  * @rpm_active: Whether or not the consumer device is runtime-PM-active.
854  * @kref: Count repeated addition of the same link.
855  * @rcu_head: An RCU head to use for deferred execution of SRCU callbacks.
856  * @supplier_preactivated: Supplier has been made active before consumer probe.
857  */
858 struct device_link {
859 	struct device *supplier;
860 	struct list_head s_node;
861 	struct device *consumer;
862 	struct list_head c_node;
863 	enum device_link_state status;
864 	u32 flags;
865 	refcount_t rpm_active;
866 	struct kref kref;
867 #ifdef CONFIG_SRCU
868 	struct rcu_head rcu_head;
869 #endif
870 	bool supplier_preactivated; /* Owned by consumer probe. */
871 };
872 
873 /**
874  * enum dl_dev_state - Device driver presence tracking information.
875  * @DL_DEV_NO_DRIVER: There is no driver attached to the device.
876  * @DL_DEV_PROBING: A driver is probing.
877  * @DL_DEV_DRIVER_BOUND: The driver has been bound to the device.
878  * @DL_DEV_UNBINDING: The driver is unbinding from the device.
879  */
880 enum dl_dev_state {
881 	DL_DEV_NO_DRIVER = 0,
882 	DL_DEV_PROBING,
883 	DL_DEV_DRIVER_BOUND,
884 	DL_DEV_UNBINDING,
885 };
886 
887 /**
888  * struct dev_links_info - Device data related to device links.
889  * @suppliers: List of links to supplier devices.
890  * @consumers: List of links to consumer devices.
891  * @status: Driver status information.
892  */
893 struct dev_links_info {
894 	struct list_head suppliers;
895 	struct list_head consumers;
896 	enum dl_dev_state status;
897 };
898 
899 /**
900  * struct device - The basic device structure
901  * @parent:	The device's "parent" device, the device to which it is attached.
902  * 		In most cases, a parent device is some sort of bus or host
903  * 		controller. If parent is NULL, the device, is a top-level device,
904  * 		which is not usually what you want.
905  * @p:		Holds the private data of the driver core portions of the device.
906  * 		See the comment of the struct device_private for detail.
907  * @kobj:	A top-level, abstract class from which other classes are derived.
908  * @init_name:	Initial name of the device.
909  * @type:	The type of device.
910  * 		This identifies the device type and carries type-specific
911  * 		information.
912  * @mutex:	Mutex to synchronize calls to its driver.
913  * @bus:	Type of bus device is on.
914  * @driver:	Which driver has allocated this
915  * @platform_data: Platform data specific to the device.
916  * 		Example: For devices on custom boards, as typical of embedded
917  * 		and SOC based hardware, Linux often uses platform_data to point
918  * 		to board-specific structures describing devices and how they
919  * 		are wired.  That can include what ports are available, chip
920  * 		variants, which GPIO pins act in what additional roles, and so
921  * 		on.  This shrinks the "Board Support Packages" (BSPs) and
922  * 		minimizes board-specific #ifdefs in drivers.
923  * @driver_data: Private pointer for driver specific info.
924  * @links:	Links to suppliers and consumers of this device.
925  * @power:	For device power management.
926  *		See Documentation/driver-api/pm/devices.rst for details.
927  * @pm_domain:	Provide callbacks that are executed during system suspend,
928  * 		hibernation, system resume and during runtime PM transitions
929  * 		along with subsystem-level and driver-level callbacks.
930  * @pins:	For device pin management.
931  *		See Documentation/driver-api/pinctl.rst for details.
932  * @msi_list:	Hosts MSI descriptors
933  * @msi_domain: The generic MSI domain this device is using.
934  * @numa_node:	NUMA node this device is close to.
935  * @dma_ops:    DMA mapping operations for this device.
936  * @dma_mask:	Dma mask (if dma'ble device).
937  * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
938  * 		hardware supports 64-bit addresses for consistent allocations
939  * 		such descriptors.
940  * @bus_dma_mask: Mask of an upstream bridge or bus which imposes a smaller DMA
941  *		limit than the device itself supports.
942  * @dma_pfn_offset: offset of DMA memory range relatively of RAM
943  * @dma_parms:	A low level driver may set these to teach IOMMU code about
944  * 		segment limitations.
945  * @dma_pools:	Dma pools (if dma'ble device).
946  * @dma_mem:	Internal for coherent mem override.
947  * @cma_area:	Contiguous memory area for dma allocations
948  * @archdata:	For arch-specific additions.
949  * @of_node:	Associated device tree node.
950  * @fwnode:	Associated device node supplied by platform firmware.
951  * @devt:	For creating the sysfs "dev".
952  * @id:		device instance
953  * @devres_lock: Spinlock to protect the resource of the device.
954  * @devres_head: The resources list of the device.
955  * @knode_class: The node used to add the device to the class list.
956  * @class:	The class of the device.
957  * @groups:	Optional attribute groups.
958  * @release:	Callback to free the device after all references have
959  * 		gone away. This should be set by the allocator of the
960  * 		device (i.e. the bus driver that discovered the device).
961  * @iommu_group: IOMMU group the device belongs to.
962  * @iommu_fwspec: IOMMU-specific properties supplied by firmware.
963  *
964  * @offline_disabled: If set, the device is permanently online.
965  * @offline:	Set after successful invocation of bus type's .offline().
966  * @of_node_reused: Set if the device-tree node is shared with an ancestor
967  *              device.
968  * @dma_coherent: this particular device is dma coherent, even if the
969  *		architecture supports non-coherent devices.
970  *
971  * At the lowest level, every device in a Linux system is represented by an
972  * instance of struct device. The device structure contains the information
973  * that the device model core needs to model the system. Most subsystems,
974  * however, track additional information about the devices they host. As a
975  * result, it is rare for devices to be represented by bare device structures;
976  * instead, that structure, like kobject structures, is usually embedded within
977  * a higher-level representation of the device.
978  */
979 struct device {
980 	struct kobject kobj;
981 	struct device		*parent;
982 
983 	struct device_private	*p;
984 
985 	const char		*init_name; /* initial name of the device */
986 	const struct device_type *type;
987 
988 	struct bus_type	*bus;		/* type of bus device is on */
989 	struct device_driver *driver;	/* which driver has allocated this
990 					   device */
991 	void		*platform_data;	/* Platform specific data, device
992 					   core doesn't touch it */
993 	void		*driver_data;	/* Driver data, set and get with
994 					   dev_set_drvdata/dev_get_drvdata */
995 	struct mutex		mutex;	/* mutex to synchronize calls to
996 					 * its driver.
997 					 */
998 
999 	struct dev_links_info	links;
1000 	struct dev_pm_info	power;
1001 	struct dev_pm_domain	*pm_domain;
1002 
1003 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
1004 	struct irq_domain	*msi_domain;
1005 #endif
1006 #ifdef CONFIG_PINCTRL
1007 	struct dev_pin_info	*pins;
1008 #endif
1009 #ifdef CONFIG_GENERIC_MSI_IRQ
1010 	struct list_head	msi_list;
1011 #endif
1012 
1013 	const struct dma_map_ops *dma_ops;
1014 	u64		*dma_mask;	/* dma mask (if dma'able device) */
1015 	u64		coherent_dma_mask;/* Like dma_mask, but for
1016 					     alloc_coherent mappings as
1017 					     not all hardware supports
1018 					     64 bit addresses for consistent
1019 					     allocations such descriptors. */
1020 	u64		bus_dma_mask;	/* upstream dma_mask constraint */
1021 	unsigned long	dma_pfn_offset;
1022 
1023 	struct device_dma_parameters *dma_parms;
1024 
1025 	struct list_head	dma_pools;	/* dma pools (if dma'ble) */
1026 
1027 #ifdef CONFIG_DMA_DECLARE_COHERENT
1028 	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
1029 					     override */
1030 #endif
1031 #ifdef CONFIG_DMA_CMA
1032 	struct cma *cma_area;		/* contiguous memory area for dma
1033 					   allocations */
1034 #endif
1035 	/* arch specific additions */
1036 	struct dev_archdata	archdata;
1037 
1038 	struct device_node	*of_node; /* associated device tree node */
1039 	struct fwnode_handle	*fwnode; /* firmware device node */
1040 
1041 #ifdef CONFIG_NUMA
1042 	int		numa_node;	/* NUMA node this device is close to */
1043 #endif
1044 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
1045 	u32			id;	/* device instance */
1046 
1047 	spinlock_t		devres_lock;
1048 	struct list_head	devres_head;
1049 
1050 	struct class		*class;
1051 	const struct attribute_group **groups;	/* optional groups */
1052 
1053 	void	(*release)(struct device *dev);
1054 	struct iommu_group	*iommu_group;
1055 	struct iommu_fwspec	*iommu_fwspec;
1056 
1057 	bool			offline_disabled:1;
1058 	bool			offline:1;
1059 	bool			of_node_reused:1;
1060 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
1061     defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
1062     defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
1063 	bool			dma_coherent:1;
1064 #endif
1065 };
1066 
1067 static inline struct device *kobj_to_dev(struct kobject *kobj)
1068 {
1069 	return container_of(kobj, struct device, kobj);
1070 }
1071 
1072 /**
1073  * device_iommu_mapped - Returns true when the device DMA is translated
1074  *			 by an IOMMU
1075  * @dev: Device to perform the check on
1076  */
1077 static inline bool device_iommu_mapped(struct device *dev)
1078 {
1079 	return (dev->iommu_group != NULL);
1080 }
1081 
1082 /* Get the wakeup routines, which depend on struct device */
1083 #include <linux/pm_wakeup.h>
1084 
1085 static inline const char *dev_name(const struct device *dev)
1086 {
1087 	/* Use the init name until the kobject becomes available */
1088 	if (dev->init_name)
1089 		return dev->init_name;
1090 
1091 	return kobject_name(&dev->kobj);
1092 }
1093 
1094 extern __printf(2, 3)
1095 int dev_set_name(struct device *dev, const char *name, ...);
1096 
1097 #ifdef CONFIG_NUMA
1098 static inline int dev_to_node(struct device *dev)
1099 {
1100 	return dev->numa_node;
1101 }
1102 static inline void set_dev_node(struct device *dev, int node)
1103 {
1104 	dev->numa_node = node;
1105 }
1106 #else
1107 static inline int dev_to_node(struct device *dev)
1108 {
1109 	return NUMA_NO_NODE;
1110 }
1111 static inline void set_dev_node(struct device *dev, int node)
1112 {
1113 }
1114 #endif
1115 
1116 static inline struct irq_domain *dev_get_msi_domain(const struct device *dev)
1117 {
1118 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
1119 	return dev->msi_domain;
1120 #else
1121 	return NULL;
1122 #endif
1123 }
1124 
1125 static inline void dev_set_msi_domain(struct device *dev, struct irq_domain *d)
1126 {
1127 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
1128 	dev->msi_domain = d;
1129 #endif
1130 }
1131 
1132 static inline void *dev_get_drvdata(const struct device *dev)
1133 {
1134 	return dev->driver_data;
1135 }
1136 
1137 static inline void dev_set_drvdata(struct device *dev, void *data)
1138 {
1139 	dev->driver_data = data;
1140 }
1141 
1142 static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
1143 {
1144 	return dev ? dev->power.subsys_data : NULL;
1145 }
1146 
1147 static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
1148 {
1149 	return dev->kobj.uevent_suppress;
1150 }
1151 
1152 static inline void dev_set_uevent_suppress(struct device *dev, int val)
1153 {
1154 	dev->kobj.uevent_suppress = val;
1155 }
1156 
1157 static inline int device_is_registered(struct device *dev)
1158 {
1159 	return dev->kobj.state_in_sysfs;
1160 }
1161 
1162 static inline void device_enable_async_suspend(struct device *dev)
1163 {
1164 	if (!dev->power.is_prepared)
1165 		dev->power.async_suspend = true;
1166 }
1167 
1168 static inline void device_disable_async_suspend(struct device *dev)
1169 {
1170 	if (!dev->power.is_prepared)
1171 		dev->power.async_suspend = false;
1172 }
1173 
1174 static inline bool device_async_suspend_enabled(struct device *dev)
1175 {
1176 	return !!dev->power.async_suspend;
1177 }
1178 
1179 static inline bool device_pm_not_required(struct device *dev)
1180 {
1181 	return dev->power.no_pm;
1182 }
1183 
1184 static inline void device_set_pm_not_required(struct device *dev)
1185 {
1186 	dev->power.no_pm = true;
1187 }
1188 
1189 static inline void dev_pm_syscore_device(struct device *dev, bool val)
1190 {
1191 #ifdef CONFIG_PM_SLEEP
1192 	dev->power.syscore = val;
1193 #endif
1194 }
1195 
1196 static inline void dev_pm_set_driver_flags(struct device *dev, u32 flags)
1197 {
1198 	dev->power.driver_flags = flags;
1199 }
1200 
1201 static inline bool dev_pm_test_driver_flags(struct device *dev, u32 flags)
1202 {
1203 	return !!(dev->power.driver_flags & flags);
1204 }
1205 
1206 static inline void device_lock(struct device *dev)
1207 {
1208 	mutex_lock(&dev->mutex);
1209 }
1210 
1211 static inline int device_lock_interruptible(struct device *dev)
1212 {
1213 	return mutex_lock_interruptible(&dev->mutex);
1214 }
1215 
1216 static inline int device_trylock(struct device *dev)
1217 {
1218 	return mutex_trylock(&dev->mutex);
1219 }
1220 
1221 static inline void device_unlock(struct device *dev)
1222 {
1223 	mutex_unlock(&dev->mutex);
1224 }
1225 
1226 static inline void device_lock_assert(struct device *dev)
1227 {
1228 	lockdep_assert_held(&dev->mutex);
1229 }
1230 
1231 static inline struct device_node *dev_of_node(struct device *dev)
1232 {
1233 	if (!IS_ENABLED(CONFIG_OF) || !dev)
1234 		return NULL;
1235 	return dev->of_node;
1236 }
1237 
1238 void driver_init(void);
1239 
1240 /*
1241  * High level routines for use by the bus drivers
1242  */
1243 extern int __must_check device_register(struct device *dev);
1244 extern void device_unregister(struct device *dev);
1245 extern void device_initialize(struct device *dev);
1246 extern int __must_check device_add(struct device *dev);
1247 extern void device_del(struct device *dev);
1248 extern int device_for_each_child(struct device *dev, void *data,
1249 		     int (*fn)(struct device *dev, void *data));
1250 extern int device_for_each_child_reverse(struct device *dev, void *data,
1251 		     int (*fn)(struct device *dev, void *data));
1252 extern struct device *device_find_child(struct device *dev, void *data,
1253 				int (*match)(struct device *dev, void *data));
1254 extern int device_rename(struct device *dev, const char *new_name);
1255 extern int device_move(struct device *dev, struct device *new_parent,
1256 		       enum dpm_order dpm_order);
1257 extern const char *device_get_devnode(struct device *dev,
1258 				      umode_t *mode, kuid_t *uid, kgid_t *gid,
1259 				      const char **tmp);
1260 
1261 static inline bool device_supports_offline(struct device *dev)
1262 {
1263 	return dev->bus && dev->bus->offline && dev->bus->online;
1264 }
1265 
1266 extern void lock_device_hotplug(void);
1267 extern void unlock_device_hotplug(void);
1268 extern int lock_device_hotplug_sysfs(void);
1269 extern int device_offline(struct device *dev);
1270 extern int device_online(struct device *dev);
1271 extern void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1272 extern void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
1273 void device_set_of_node_from_dev(struct device *dev, const struct device *dev2);
1274 
1275 static inline int dev_num_vf(struct device *dev)
1276 {
1277 	if (dev->bus && dev->bus->num_vf)
1278 		return dev->bus->num_vf(dev);
1279 	return 0;
1280 }
1281 
1282 /*
1283  * Root device objects for grouping under /sys/devices
1284  */
1285 extern struct device *__root_device_register(const char *name,
1286 					     struct module *owner);
1287 
1288 /* This is a macro to avoid include problems with THIS_MODULE */
1289 #define root_device_register(name) \
1290 	__root_device_register(name, THIS_MODULE)
1291 
1292 extern void root_device_unregister(struct device *root);
1293 
1294 static inline void *dev_get_platdata(const struct device *dev)
1295 {
1296 	return dev->platform_data;
1297 }
1298 
1299 /*
1300  * Manual binding of a device to driver. See drivers/base/bus.c
1301  * for information on use.
1302  */
1303 extern int __must_check device_bind_driver(struct device *dev);
1304 extern void device_release_driver(struct device *dev);
1305 extern int  __must_check device_attach(struct device *dev);
1306 extern int __must_check driver_attach(struct device_driver *drv);
1307 extern void device_initial_probe(struct device *dev);
1308 extern int __must_check device_reprobe(struct device *dev);
1309 
1310 extern bool device_is_bound(struct device *dev);
1311 
1312 /*
1313  * Easy functions for dynamically creating devices on the fly
1314  */
1315 extern __printf(5, 0)
1316 struct device *device_create_vargs(struct class *cls, struct device *parent,
1317 				   dev_t devt, void *drvdata,
1318 				   const char *fmt, va_list vargs);
1319 extern __printf(5, 6)
1320 struct device *device_create(struct class *cls, struct device *parent,
1321 			     dev_t devt, void *drvdata,
1322 			     const char *fmt, ...);
1323 extern __printf(6, 7)
1324 struct device *device_create_with_groups(struct class *cls,
1325 			     struct device *parent, dev_t devt, void *drvdata,
1326 			     const struct attribute_group **groups,
1327 			     const char *fmt, ...);
1328 extern void device_destroy(struct class *cls, dev_t devt);
1329 
1330 extern int __must_check device_add_groups(struct device *dev,
1331 					const struct attribute_group **groups);
1332 extern void device_remove_groups(struct device *dev,
1333 				 const struct attribute_group **groups);
1334 
1335 static inline int __must_check device_add_group(struct device *dev,
1336 					const struct attribute_group *grp)
1337 {
1338 	const struct attribute_group *groups[] = { grp, NULL };
1339 
1340 	return device_add_groups(dev, groups);
1341 }
1342 
1343 static inline void device_remove_group(struct device *dev,
1344 				       const struct attribute_group *grp)
1345 {
1346 	const struct attribute_group *groups[] = { grp, NULL };
1347 
1348 	return device_remove_groups(dev, groups);
1349 }
1350 
1351 extern int __must_check devm_device_add_groups(struct device *dev,
1352 					const struct attribute_group **groups);
1353 extern void devm_device_remove_groups(struct device *dev,
1354 				      const struct attribute_group **groups);
1355 extern int __must_check devm_device_add_group(struct device *dev,
1356 					const struct attribute_group *grp);
1357 extern void devm_device_remove_group(struct device *dev,
1358 				     const struct attribute_group *grp);
1359 
1360 /*
1361  * Platform "fixup" functions - allow the platform to have their say
1362  * about devices and actions that the general device layer doesn't
1363  * know about.
1364  */
1365 /* Notify platform of device discovery */
1366 extern int (*platform_notify)(struct device *dev);
1367 
1368 extern int (*platform_notify_remove)(struct device *dev);
1369 
1370 
1371 /*
1372  * get_device - atomically increment the reference count for the device.
1373  *
1374  */
1375 extern struct device *get_device(struct device *dev);
1376 extern void put_device(struct device *dev);
1377 
1378 #ifdef CONFIG_DEVTMPFS
1379 extern int devtmpfs_create_node(struct device *dev);
1380 extern int devtmpfs_delete_node(struct device *dev);
1381 extern int devtmpfs_mount(const char *mntdir);
1382 #else
1383 static inline int devtmpfs_create_node(struct device *dev) { return 0; }
1384 static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
1385 static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
1386 #endif
1387 
1388 /* drivers/base/power/shutdown.c */
1389 extern void device_shutdown(void);
1390 
1391 /* debugging and troubleshooting/diagnostic helpers. */
1392 extern const char *dev_driver_string(const struct device *dev);
1393 
1394 /* Device links interface. */
1395 struct device_link *device_link_add(struct device *consumer,
1396 				    struct device *supplier, u32 flags);
1397 void device_link_del(struct device_link *link);
1398 void device_link_remove(void *consumer, struct device *supplier);
1399 
1400 #ifndef dev_fmt
1401 #define dev_fmt(fmt) fmt
1402 #endif
1403 
1404 #ifdef CONFIG_PRINTK
1405 
1406 __printf(3, 0) __cold
1407 int dev_vprintk_emit(int level, const struct device *dev,
1408 		     const char *fmt, va_list args);
1409 __printf(3, 4) __cold
1410 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...);
1411 
1412 __printf(3, 4) __cold
1413 void dev_printk(const char *level, const struct device *dev,
1414 		const char *fmt, ...);
1415 __printf(2, 3) __cold
1416 void _dev_emerg(const struct device *dev, const char *fmt, ...);
1417 __printf(2, 3) __cold
1418 void _dev_alert(const struct device *dev, const char *fmt, ...);
1419 __printf(2, 3) __cold
1420 void _dev_crit(const struct device *dev, const char *fmt, ...);
1421 __printf(2, 3) __cold
1422 void _dev_err(const struct device *dev, const char *fmt, ...);
1423 __printf(2, 3) __cold
1424 void _dev_warn(const struct device *dev, const char *fmt, ...);
1425 __printf(2, 3) __cold
1426 void _dev_notice(const struct device *dev, const char *fmt, ...);
1427 __printf(2, 3) __cold
1428 void _dev_info(const struct device *dev, const char *fmt, ...);
1429 
1430 #else
1431 
1432 static inline __printf(3, 0)
1433 int dev_vprintk_emit(int level, const struct device *dev,
1434 		     const char *fmt, va_list args)
1435 { return 0; }
1436 static inline __printf(3, 4)
1437 int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
1438 { return 0; }
1439 
1440 static inline void __dev_printk(const char *level, const struct device *dev,
1441 				struct va_format *vaf)
1442 {}
1443 static inline __printf(3, 4)
1444 void dev_printk(const char *level, const struct device *dev,
1445 		 const char *fmt, ...)
1446 {}
1447 
1448 static inline __printf(2, 3)
1449 void _dev_emerg(const struct device *dev, const char *fmt, ...)
1450 {}
1451 static inline __printf(2, 3)
1452 void _dev_crit(const struct device *dev, const char *fmt, ...)
1453 {}
1454 static inline __printf(2, 3)
1455 void _dev_alert(const struct device *dev, const char *fmt, ...)
1456 {}
1457 static inline __printf(2, 3)
1458 void _dev_err(const struct device *dev, const char *fmt, ...)
1459 {}
1460 static inline __printf(2, 3)
1461 void _dev_warn(const struct device *dev, const char *fmt, ...)
1462 {}
1463 static inline __printf(2, 3)
1464 void _dev_notice(const struct device *dev, const char *fmt, ...)
1465 {}
1466 static inline __printf(2, 3)
1467 void _dev_info(const struct device *dev, const char *fmt, ...)
1468 {}
1469 
1470 #endif
1471 
1472 /*
1473  * #defines for all the dev_<level> macros to prefix with whatever
1474  * possible use of #define dev_fmt(fmt) ...
1475  */
1476 
1477 #define dev_emerg(dev, fmt, ...)					\
1478 	_dev_emerg(dev, dev_fmt(fmt), ##__VA_ARGS__)
1479 #define dev_crit(dev, fmt, ...)						\
1480 	_dev_crit(dev, dev_fmt(fmt), ##__VA_ARGS__)
1481 #define dev_alert(dev, fmt, ...)					\
1482 	_dev_alert(dev, dev_fmt(fmt), ##__VA_ARGS__)
1483 #define dev_err(dev, fmt, ...)						\
1484 	_dev_err(dev, dev_fmt(fmt), ##__VA_ARGS__)
1485 #define dev_warn(dev, fmt, ...)						\
1486 	_dev_warn(dev, dev_fmt(fmt), ##__VA_ARGS__)
1487 #define dev_notice(dev, fmt, ...)					\
1488 	_dev_notice(dev, dev_fmt(fmt), ##__VA_ARGS__)
1489 #define dev_info(dev, fmt, ...)						\
1490 	_dev_info(dev, dev_fmt(fmt), ##__VA_ARGS__)
1491 
1492 #if defined(CONFIG_DYNAMIC_DEBUG)
1493 #define dev_dbg(dev, fmt, ...)						\
1494 	dynamic_dev_dbg(dev, dev_fmt(fmt), ##__VA_ARGS__)
1495 #elif defined(DEBUG)
1496 #define dev_dbg(dev, fmt, ...)						\
1497 	dev_printk(KERN_DEBUG, dev, dev_fmt(fmt), ##__VA_ARGS__)
1498 #else
1499 #define dev_dbg(dev, fmt, ...)						\
1500 ({									\
1501 	if (0)								\
1502 		dev_printk(KERN_DEBUG, dev, dev_fmt(fmt), ##__VA_ARGS__); \
1503 })
1504 #endif
1505 
1506 #ifdef CONFIG_PRINTK
1507 #define dev_level_once(dev_level, dev, fmt, ...)			\
1508 do {									\
1509 	static bool __print_once __read_mostly;				\
1510 									\
1511 	if (!__print_once) {						\
1512 		__print_once = true;					\
1513 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1514 	}								\
1515 } while (0)
1516 #else
1517 #define dev_level_once(dev_level, dev, fmt, ...)			\
1518 do {									\
1519 	if (0)								\
1520 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1521 } while (0)
1522 #endif
1523 
1524 #define dev_emerg_once(dev, fmt, ...)					\
1525 	dev_level_once(dev_emerg, dev, fmt, ##__VA_ARGS__)
1526 #define dev_alert_once(dev, fmt, ...)					\
1527 	dev_level_once(dev_alert, dev, fmt, ##__VA_ARGS__)
1528 #define dev_crit_once(dev, fmt, ...)					\
1529 	dev_level_once(dev_crit, dev, fmt, ##__VA_ARGS__)
1530 #define dev_err_once(dev, fmt, ...)					\
1531 	dev_level_once(dev_err, dev, fmt, ##__VA_ARGS__)
1532 #define dev_warn_once(dev, fmt, ...)					\
1533 	dev_level_once(dev_warn, dev, fmt, ##__VA_ARGS__)
1534 #define dev_notice_once(dev, fmt, ...)					\
1535 	dev_level_once(dev_notice, dev, fmt, ##__VA_ARGS__)
1536 #define dev_info_once(dev, fmt, ...)					\
1537 	dev_level_once(dev_info, dev, fmt, ##__VA_ARGS__)
1538 #define dev_dbg_once(dev, fmt, ...)					\
1539 	dev_level_once(dev_dbg, dev, fmt, ##__VA_ARGS__)
1540 
1541 #define dev_level_ratelimited(dev_level, dev, fmt, ...)			\
1542 do {									\
1543 	static DEFINE_RATELIMIT_STATE(_rs,				\
1544 				      DEFAULT_RATELIMIT_INTERVAL,	\
1545 				      DEFAULT_RATELIMIT_BURST);		\
1546 	if (__ratelimit(&_rs))						\
1547 		dev_level(dev, fmt, ##__VA_ARGS__);			\
1548 } while (0)
1549 
1550 #define dev_emerg_ratelimited(dev, fmt, ...)				\
1551 	dev_level_ratelimited(dev_emerg, dev, fmt, ##__VA_ARGS__)
1552 #define dev_alert_ratelimited(dev, fmt, ...)				\
1553 	dev_level_ratelimited(dev_alert, dev, fmt, ##__VA_ARGS__)
1554 #define dev_crit_ratelimited(dev, fmt, ...)				\
1555 	dev_level_ratelimited(dev_crit, dev, fmt, ##__VA_ARGS__)
1556 #define dev_err_ratelimited(dev, fmt, ...)				\
1557 	dev_level_ratelimited(dev_err, dev, fmt, ##__VA_ARGS__)
1558 #define dev_warn_ratelimited(dev, fmt, ...)				\
1559 	dev_level_ratelimited(dev_warn, dev, fmt, ##__VA_ARGS__)
1560 #define dev_notice_ratelimited(dev, fmt, ...)				\
1561 	dev_level_ratelimited(dev_notice, dev, fmt, ##__VA_ARGS__)
1562 #define dev_info_ratelimited(dev, fmt, ...)				\
1563 	dev_level_ratelimited(dev_info, dev, fmt, ##__VA_ARGS__)
1564 #if defined(CONFIG_DYNAMIC_DEBUG)
1565 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
1566 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1567 do {									\
1568 	static DEFINE_RATELIMIT_STATE(_rs,				\
1569 				      DEFAULT_RATELIMIT_INTERVAL,	\
1570 				      DEFAULT_RATELIMIT_BURST);		\
1571 	DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);			\
1572 	if (DYNAMIC_DEBUG_BRANCH(descriptor) &&				\
1573 	    __ratelimit(&_rs))						\
1574 		__dynamic_dev_dbg(&descriptor, dev, dev_fmt(fmt),	\
1575 				  ##__VA_ARGS__);			\
1576 } while (0)
1577 #elif defined(DEBUG)
1578 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1579 do {									\
1580 	static DEFINE_RATELIMIT_STATE(_rs,				\
1581 				      DEFAULT_RATELIMIT_INTERVAL,	\
1582 				      DEFAULT_RATELIMIT_BURST);		\
1583 	if (__ratelimit(&_rs))						\
1584 		dev_printk(KERN_DEBUG, dev, dev_fmt(fmt), ##__VA_ARGS__); \
1585 } while (0)
1586 #else
1587 #define dev_dbg_ratelimited(dev, fmt, ...)				\
1588 do {									\
1589 	if (0)								\
1590 		dev_printk(KERN_DEBUG, dev, dev_fmt(fmt), ##__VA_ARGS__); \
1591 } while (0)
1592 #endif
1593 
1594 #ifdef VERBOSE_DEBUG
1595 #define dev_vdbg	dev_dbg
1596 #else
1597 #define dev_vdbg(dev, fmt, ...)						\
1598 ({									\
1599 	if (0)								\
1600 		dev_printk(KERN_DEBUG, dev, dev_fmt(fmt), ##__VA_ARGS__); \
1601 })
1602 #endif
1603 
1604 /*
1605  * dev_WARN*() acts like dev_printk(), but with the key difference of
1606  * using WARN/WARN_ONCE to include file/line information and a backtrace.
1607  */
1608 #define dev_WARN(dev, format, arg...) \
1609 	WARN(1, "%s %s: " format, dev_driver_string(dev), dev_name(dev), ## arg);
1610 
1611 #define dev_WARN_ONCE(dev, condition, format, arg...) \
1612 	WARN_ONCE(condition, "%s %s: " format, \
1613 			dev_driver_string(dev), dev_name(dev), ## arg)
1614 
1615 /* Create alias, so I can be autoloaded. */
1616 #define MODULE_ALIAS_CHARDEV(major,minor) \
1617 	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
1618 #define MODULE_ALIAS_CHARDEV_MAJOR(major) \
1619 	MODULE_ALIAS("char-major-" __stringify(major) "-*")
1620 
1621 #ifdef CONFIG_SYSFS_DEPRECATED
1622 extern long sysfs_deprecated;
1623 #else
1624 #define sysfs_deprecated 0
1625 #endif
1626 
1627 /**
1628  * module_driver() - Helper macro for drivers that don't do anything
1629  * special in module init/exit. This eliminates a lot of boilerplate.
1630  * Each module may only use this macro once, and calling it replaces
1631  * module_init() and module_exit().
1632  *
1633  * @__driver: driver name
1634  * @__register: register function for this driver type
1635  * @__unregister: unregister function for this driver type
1636  * @...: Additional arguments to be passed to __register and __unregister.
1637  *
1638  * Use this macro to construct bus specific macros for registering
1639  * drivers, and do not use it on its own.
1640  */
1641 #define module_driver(__driver, __register, __unregister, ...) \
1642 static int __init __driver##_init(void) \
1643 { \
1644 	return __register(&(__driver) , ##__VA_ARGS__); \
1645 } \
1646 module_init(__driver##_init); \
1647 static void __exit __driver##_exit(void) \
1648 { \
1649 	__unregister(&(__driver) , ##__VA_ARGS__); \
1650 } \
1651 module_exit(__driver##_exit);
1652 
1653 /**
1654  * builtin_driver() - Helper macro for drivers that don't do anything
1655  * special in init and have no exit. This eliminates some boilerplate.
1656  * Each driver may only use this macro once, and calling it replaces
1657  * device_initcall (or in some cases, the legacy __initcall).  This is
1658  * meant to be a direct parallel of module_driver() above but without
1659  * the __exit stuff that is not used for builtin cases.
1660  *
1661  * @__driver: driver name
1662  * @__register: register function for this driver type
1663  * @...: Additional arguments to be passed to __register
1664  *
1665  * Use this macro to construct bus specific macros for registering
1666  * drivers, and do not use it on its own.
1667  */
1668 #define builtin_driver(__driver, __register, ...) \
1669 static int __init __driver##_init(void) \
1670 { \
1671 	return __register(&(__driver) , ##__VA_ARGS__); \
1672 } \
1673 device_initcall(__driver##_init);
1674 
1675 #endif /* _DEVICE_H_ */
1676