summaryrefslogtreecommitdiffstats
path: root/include/linux/device.h
blob: 8ff7dc801fd518544e1da601364ae3d18422503c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
/*
 * device.h - generic, centralized driver model
 *
 * Copyright (c) 2001-2003 Patrick Mochel <mochel@osdl.org>
 * Copyright (c) 2004-2009 Greg Kroah-Hartman <gregkh@suse.de>
 * Copyright (c) 2008-2009 Novell Inc.
 *
 * This file is released under the GPLv2
 *
 * See Documentation/driver-model/ for more information.
 */

#ifndef _DEVICE_H_
#define _DEVICE_H_

#include <linux/ioport.h>
#include <linux/kobject.h>
#include <linux/klist.h>
#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/compiler.h>
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/pm.h>
#include <linux/atomic.h>
#include <asm/device.h>

struct device;
struct device_private;
struct device_driver;
struct driver_private;
struct module;
struct class;
struct subsys_private;
struct bus_type;
struct device_node;
struct iommu_ops;

struct bus_attribute {
	struct attribute	attr;
	ssize_t (*show)(struct bus_type *bus, char *buf);
	ssize_t (*store)(struct bus_type *bus, const char *buf, size_t count);
};

#define BUS_ATTR(_name, _mode, _show, _store)	\
struct bus_attribute bus_attr_##_name = __ATTR(_name, _mode, _show, _store)

extern int __must_check bus_create_file(struct bus_type *,
					struct bus_attribute *);
extern void bus_remove_file(struct bus_type *, struct bus_attribute *);

/**
 * struct bus_type - The bus type of the device
 *
 * @name:	The name of the bus.
 * @bus_attrs:	Default attributes of the bus.
 * @dev_attrs:	Default attributes of the devices on the bus.
 * @drv_attrs:	Default attributes of the device drivers on the bus.
 * @match:	Called, perhaps multiple times, whenever a new device or driver
 *		is added for this bus. It should return a nonzero value if the
 *		given device can be handled by the given driver.
 * @uevent:	Called when a device is added, removed, or a few other things
 *		that generate uevents to add the environment variables.
 * @probe:	Called when a new device or driver add to this bus, and callback
 *		the specific driver's probe to initial the matched device.
 * @remove:	Called when a device removed from this bus.
 * @shutdown:	Called at shut-down time to quiesce the device.
 * @suspend:	Called when a device on this bus wants to go to sleep mode.
 * @resume:	Called to bring a device on this bus out of sleep mode.
 * @pm:		Power management operations of this bus, callback the specific
 *		device driver's pm-ops.
 * @iommu_ops   IOMMU specific operations for this bus, used to attach IOMMU
 *              driver implementations to a bus and allow the driver to do
 *              bus-specific setup
 * @p:		The private data of the driver core, only the driver core can
 *		touch this.
 *
 * A bus is a channel between the processor and one or more devices. For the
 * purposes of the device model, all devices are connected via a bus, even if
 * it is an internal, virtual, "platform" bus. Buses can plug into each other.
 * A USB controller is usually a PCI device, for example. The device model
 * represents the actual connections between buses and the devices they control.
 * A bus is represented by the bus_type structure. It contains the name, the
 * default attributes, the bus' methods, PM operations, and the driver core's
 * private data.
 */
struct bus_type {
	const char		*name;
	struct bus_attribute	*bus_attrs;
	struct device_attribute	*dev_attrs;
	struct driver_attribute	*drv_attrs;

	int (*match)(struct device *dev, struct device_driver *drv);
	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
	int (*probe)(struct device *dev);
	int (*remove)(struct device *dev);
	void (*shutdown)(struct device *dev);

	int (*suspend)(struct device *dev, pm_message_t state);
	int (*resume)(struct device *dev);

	const struct dev_pm_ops *pm;

	struct iommu_ops *iommu_ops;

	struct subsys_private *p;
};

extern int __must_check bus_register(struct bus_type *bus);
extern void bus_unregister(struct bus_type *bus);

extern int __must_check bus_rescan_devices(struct bus_type *bus);

/* iterator helpers for buses */

int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data,
		     int (*fn)(struct device *dev, void *data));
struct device *bus_find_device(struct bus_type *bus, struct device *start,
			       void *data,
			       int (*match)(struct device *dev, void *data));
struct device *bus_find_device_by_name(struct bus_type *bus,
				       struct device *start,
				       const char *name);

int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
		     void *data, int (*fn)(struct device_driver *, void *));

void bus_sort_breadthfirst(struct bus_type *bus,
			   int (*compare)(const struct device *a,
					  const struct device *b));
/*
 * Bus notifiers: Get notified of addition/removal of devices
 * and binding/unbinding of drivers to devices.
 * In the long run, it should be a replacement for the platform
 * notify hooks.
 */
struct notifier_block;

extern int bus_register_notifier(struct bus_type *bus,
				 struct notifier_block *nb);
extern int bus_unregister_notifier(struct bus_type *bus,
				   struct notifier_block *nb);

/* All 4 notifers below get called with the target struct device *
 * as an argument. Note that those functions are likely to be called
 * with the device lock held in the core, so be careful.
 */
#define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
#define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device removed */
#define BUS_NOTIFY_BIND_DRIVER		0x00000003 /* driver about to be
						      bound */
#define BUS_NOTIFY_BOUND_DRIVER		0x00000004 /* driver bound to device */
#define BUS_NOTIFY_UNBIND_DRIVER	0x00000005 /* driver about to be
						      unbound */
#define BUS_NOTIFY_UNBOUND_DRIVER	0x00000006 /* driver is unbound
						      from the device */

extern struct kset *bus_get_kset(struct bus_type *bus);
extern struct klist *bus_get_device_klist(struct bus_type *bus);

/**
 * struct device_driver - The basic device driver structure
 * @name:	Name of the device driver.
 * @bus:	The bus which the device of this driver belongs to.
 * @owner:	The module owner.
 * @mod_name:	Used for built-in modules.
 * @suppress_bind_attrs: Disables bind/unbind via sysfs.
 * @of_match_table: The open firmware table.
 * @probe:	Called to query the existence of a specific device,
 *		whether this driver can work with it, and bind the driver
 *		to a specific device.
 * @remove:	Called when the device is removed from the system to
 *		unbind a device from this driver.
 * @shutdown:	Called at shut-down time to quiesce the device.
 * @suspend:	Called to put the device to sleep mode. Usually to a
 *		low power state.
 * @resume:	Called to bring a device from sleep mode.
 * @groups:	Default attributes that get created by the driver core
 *		automatically.
 * @pm:		Power management operations of the device which matched
 *		this driver.
 * @p:		Driver core's private data, no one other than the driver
 *		core can touch this.
 *
 * The device driver-model tracks all of the drivers known to the system.
 * The main reason for this tracking is to enable the driver core to match
 * up drivers with new devices. Once drivers are known objects within the
 * system, however, a number of other things become possible. Device drivers
 * can export information and configuration variables that are independent
 * of any specific device.
 */
struct device_driver {
	const char		*name;
	struct bus_type		*bus;

	struct module		*owner;
	const char		*mod_name;	/* used for built-in modules */

	bool suppress_bind_attrs;	/* disables bind/unbind via sysfs */

	const struct of_device_id	*of_match_table;

	int (*probe) (struct device *dev);
	int (*remove) (struct device *dev);
	void (*shutdown) (struct device *dev);
	int (*suspend) (struct device *dev, pm_message_t state);
	int (*resume) (struct device *dev);
	const struct attribute_group **groups;

	const struct dev_pm_ops *pm;

	struct driver_private *p;
};


extern int __must_check driver_register(struct device_driver *drv);
extern void driver_unregister(struct device_driver *drv);

extern struct device_driver *get_driver(struct device_driver *drv);
extern void put_driver(struct device_driver *drv);
extern struct device_driver *driver_find(const char *name,
					 struct bus_type *bus);
extern int driver_probe_done(void);
extern void wait_for_device_probe(void);


/* sysfs interface for exporting driver attributes */

struct driver_attribute {
	struct attribute attr;
	ssize_t (*show)(struct device_driver *driver, char *buf);
	ssize_t (*store)(struct device_driver *driver, const char *buf,
			 size_t count);
};

#define DRIVER_ATTR(_name, _mode, _show, _store)	\
struct driver_attribute driver_attr_##_name =		\
	__ATTR(_name, _mode, _show, _store)

extern int __must_check driver_create_file(struct device_driver *driver,
					const struct driver_attribute *attr);
extern void driver_remove_file(struct device_driver *driver,
			       const struct driver_attribute *attr);

extern int __must_check driver_add_kobj(struct device_driver *drv,
					struct kobject *kobj,
					const char *fmt, ...);

extern int __must_check driver_for_each_device(struct device_driver *drv,
					       struct device *start,
					       void *data,
					       int (*fn)(struct device *dev,
							 void *));
struct device *driver_find_device(struct device_driver *drv,
				  struct device *start, void *data,
				  int (*match)(struct device *dev, void *data));

/**
 * struct class - device classes
 * @name:	Name of the class.
 * @owner:	The module owner.
 * @class_attrs: Default attributes of this class.
 * @dev_attrs:	Default attributes of the devices belong to the class.
 * @dev_bin_attrs: Default binary attributes of the devices belong to the class.
 * @dev_kobj:	The kobject that represents this class and links it into the hierarchy.
 * @dev_uevent:	Called when a device is added, removed from this class, or a
 *		few other things that generate uevents to add the environment
 *		variables.
 * @devnode:	Callback to provide the devtmpfs.
 * @class_release: Called to release this class.
 * @dev_release: Called to release the device.
 * @suspend:	Used to put the device to sleep mode, usually to a low power
 *		state.
 * @resume:	Used to bring the device from the sleep mode.
 * @ns_type:	Callbacks so sysfs can detemine namespaces.
 * @namespace:	Namespace of the device belongs to this class.
 * @pm:		The default device power management operations of this class.
 * @p:		The private data of the driver core, no one other than the
 *		driver core can touch this.
 *
 * A class is a higher-level view of a device that abstracts out low-level
 * implementation details. Drivers may see a SCSI disk or an ATA disk, but,
 * at the class level, they are all simply disks. Classes allow user space
 * to work with devices based on what they do, rather than how they are
 * connected or how they work.
 */
struct class {
	const char		*name;
	struct module		*owner;

	struct class_attribute		*class_attrs;
	struct device_attribute		*dev_attrs;
	struct bin_attribute		*dev_bin_attrs;
	struct kobject			*dev_kobj;

	int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env);
	char *(*devnode)(struct device *dev, mode_t *mode);

	void (*class_release)(struct class *class);
	void (*dev_release)(struct device *dev);

	int (*suspend)(struct device *dev, pm_message_t state);
	int (*resume)(struct device *dev);

	const struct kobj_ns_type_operations *ns_type;
	const void *(*namespace)(struct device *dev);

	const struct dev_pm_ops *pm;

	struct subsys_private *p;
};

struct class_dev_iter {
	struct klist_iter		ki;
	const struct device_type	*type;
};

extern struct kobject *sysfs_dev_block_kobj;
extern struct kobject *sysfs_dev_char_kobj;
extern int __must_check __class_register(struct class *class,
					 struct lock_class_key *key);
extern void class_unregister(struct class *class);

/* This is a #define to keep the compiler from merging different
 * instances of the __key variable */
#define class_register(class)			\
({						\
	static struct lock_class_key __key;	\
	__class_register(class, &__key);	\
})

struct class_compat;
struct class_compat *class_compat_register(const char *name);
void class_compat_unregister(struct class_compat *cls);
int class_compat_create_link(struct class_compat *cls, struct device *dev,
			     struct device *device_link);
void class_compat_remove_link(struct class_compat *cls, struct device *dev,
			      struct device *device_link);

extern void class_dev_iter_init(struct class_dev_iter *iter,
				struct class *class,
				struct device *start,
				const struct device_type *type);
extern struct device *class_dev_iter_next(struct class_dev_iter *iter);
extern void class_dev_iter_exit(struct class_dev_iter *iter);

extern int class_for_each_device(struct class *class, struct device *start,
				 void *data,
				 int (*fn)(struct device *dev, void *data));
extern struct device *class_find_device(struct class *class,
					struct device *start, void *data,
					int (*match)(struct device *, void *));

struct class_attribute {
	struct attribute attr;
	ssize_t (*show)(struct class *class, struct class_attribute *attr,
			char *buf);
	ssize_t (*store)(struct class *class, struct class_attribute *attr,
			const char *buf, size_t count);
	const void *(*namespace)(struct class *class,
				 const struct class_attribute *attr);
};

#define CLASS_ATTR(_name, _mode, _show, _store)			\
struct class_attribute class_attr_##_name = __ATTR(_name, _mode, _show, _store)

extern int __must_check class_create_file(struct class *class,
					  const struct class_attribute *attr);
extern void class_remove_file(struct class *class,
			      const struct class_attribute *attr);

/* Simple class attribute that is just a static string */

struct class_attribute_string {
	struct class_attribute attr;
	char *str;
};

/* Currently read-only only */
#define _CLASS_ATTR_STRING(_name, _mode, _str) \
	{ __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
#define CLASS_ATTR_STRING(_name, _mode, _str) \
	struct class_attribute_string class_attr_##_name = \
		_CLASS_ATTR_STRING(_name, _mode, _str)

extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
                        char *buf);

struct class_interface {
	struct list_head	node;
	struct class		*class;

	int (*add_dev)		(struct device *, struct class_interface *);
	void (*remove_dev)	(struct device *, struct class_interface *);
};

extern int __must_check class_interface_register(struct class_interface *);
extern void class_interface_unregister(struct class_interface *);

extern struct class * __must_check __class_create(struct module *owner,
						  const char *name,
						  struct lock_class_key *key);
extern void class_destroy(struct class *cls);

/* This is a #define to keep the compiler from merging different
 * instances of the __key variable */
#define class_create(owner, name)		\
({						\
	static struct lock_class_key __key;	\
	__class_create(owner, name, &__key);	\
})

/*
 * The type of device, "struct device" is embedded in. A class
 * or bus can contain devices of different types
 * like "partitions" and "disks", "mouse" and "event".
 * This identifies the device type and carries type-specific
 * information, equivalent to the kobj_type of a kobject.
 * If "name" is specified, the uevent will contain it in
 * the DEVTYPE variable.
 */
struct device_type {
	const char *name;
	const struct attribute_group **groups;
	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
	char *(*devnode)(struct device *dev, mode_t *mode);
	void (*release)(struct device *dev);

	const struct dev_pm_ops *pm;
};

/* interface for exporting device attributes */
struct device_attribute {
	struct attribute	attr;
	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
			char *buf);
	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
			 const char *buf, size_t count);
};

#define DEVICE_ATTR(_name, _mode, _show, _store) \
struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)

extern int __must_check device_create_file(struct device *device,
					const struct device_attribute *entry);
extern void device_remove_file(struct device *dev,
			       const struct device_attribute *attr);
extern int __must_check device_create_bin_file(struct device *dev,
					const struct bin_attribute *attr);
extern void device_remove_bin_file(struct device *dev,
				   const struct bin_attribute *attr);
extern int device_schedule_callback_owner(struct device *dev,
		void (*func)(struct device *dev), struct module *owner);

/* This is a macro to avoid include problems with THIS_MODULE */
#define device_schedule_callback(dev, func)			\
	device_schedule_callback_owner(dev, func, THIS_MODULE)

/* device resource management */
typedef void (*dr_release_t)(struct device *dev, void *res);
typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);

#ifdef CONFIG_DEBUG_DEVRES
extern void *__devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
			     const char *name);
#define devres_alloc(release, size, gfp) \
	__devres_alloc(release, size, gfp, #release)
#else
extern void *devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
#endif
extern void devres_free(void *res);
extern void devres_add(struct device *dev, void *res);
extern void *devres_find(struct device *dev, dr_release_t release,
			 dr_match_t match, void *match_data);
extern void *devres_get(struct device *dev, void *new_res,
			dr_match_t match, void *match_data);
extern void *devres_remove(struct device *dev, dr_release_t release,
			   dr_match_t match, void *match_data);
extern int devres_destroy(struct device *dev, dr_release_t release,
			  dr_match_t match, void *match_data);

/* devres group */
extern void * __must_check devres_open_group(struct device *dev, void *id,
					     gfp_t gfp);
extern void devres_close_group(struct device *dev, void *id);
extern void devres_remove_group(struct device *dev, void *id);
extern int devres_release_group(struct device *dev, void *id);

/* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
extern void devm_kfree(struct device *dev, void *p);

struct device_dma_parameters {
	/*
	 * a low level driver may set these to teach IOMMU code about
	 * sg limitations.
	 */
	unsigned int max_segment_size;
	unsigned long segment_boundary_mask;
};

/**
 * struct device - The basic device structure
 * @parent:	The device's "parent" device, the device to which it is attached.
 * 		In most cases, a parent device is some sort of bus or host
 * 		controller. If parent is NULL, the device, is a top-level device,
 * 		which is not usually what you want.
 * @p:		Holds the private data of the driver core portions of the device.
 * 		See the comment of the struct device_private for detail.
 * @kobj:	A top-level, abstract class from which other classes are derived.
 * @init_name:	Initial name of the device.
 * @type:	The type of device.
 * 		This identifies the device type and carries type-specific
 * 		information.
 * @mutex:	Mutex to synchronize calls to its driver.
 * @bus:	Type of bus device is on.
 * @driver:	Which driver has allocated this
 * @platform_data: Platform data specific to the device.
 * 		Example: For devices on custom boards, as typical of embedded
 * 		and SOC based hardware, Linux often uses platform_data to point
 * 		to board-specific structures describing devices and how they
 * 		are wired.  That can include what ports are available, chip
 * 		variants, which GPIO pins act in what additional roles, and so
 * 		on.  This shrinks the "Board Support Packages" (BSPs) and
 * 		minimizes board-specific #ifdefs in drivers.
 * @power:	For device power management.
 * 		See Documentation/power/devices.txt for details.
 * @pm_domain:	Provide callbacks that are executed during system suspend,
 * 		hibernation, system resume and during runtime PM transitions
 * 		along with subsystem-level and driver-level callbacks.
 * @numa_node:	NUMA node this device is close to.
 * @dma_mask:	Dma mask (if dma'ble device).
 * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all
 * 		hardware supports 64-bit addresses for consistent allocations
 * 		such descriptors.
 * @dma_parms:	A low level driver may set these to teach IOMMU code about
 * 		segment limitations.
 * @dma_pools:	Dma pools (if dma'ble device).
 * @dma_mem:	Internal for coherent mem override.
 * @archdata:	For arch-specific additions.
 * @of_node:	Associated device tree node.
 * @devt:	For creating the sysfs "dev".
 * @devres_lock: Spinlock to protect the resource of the device.
 * @devres_head: The resources list of the device.
 * @knode_class: The node used to add the device to the class list.
 * @class:	The class of the device.
 * @groups:	Optional attribute groups.
 * @release:	Callback to free the device after all references have
 * 		gone away. This should be set by the allocator of the
 * 		device (i.e. the bus driver that discovered the device).
 *
 * At the lowest level, every device in a Linux system is represented by an
 * instance of struct device. The device structure contains the information
 * that the device model core needs to model the system. Most subsystems,
 * however, track additional information about the devices they host. As a
 * result, it is rare for devices to be represented by bare device structures;
 * instead, that structure, like kobject structures, is usually embedded within
 * a higher-level representation of the device.
 */
struct device {
	struct device		*parent;

	struct device_private	*p;

	struct kobject kobj;
	const char		*init_name; /* initial name of the device */
	const struct device_type *type;

	struct mutex		mutex;	/* mutex to synchronize calls to
					 * its driver.
					 */

	struct bus_type	*bus;		/* type of bus device is on */
	struct device_driver *driver;	/* which driver has allocated this
					   device */
	void		*platform_data;	/* Platform specific data, device
					   core doesn't touch it */
	struct dev_pm_info	power;
	struct dev_pm_domain	*pm_domain;

#ifdef CONFIG_NUMA
	int		numa_node;	/* NUMA node this device is close to */
#endif
	u64		*dma_mask;	/* dma mask (if dma'able device) */
	u64		coherent_dma_mask;/* Like dma_mask, but for
					     alloc_coherent mappings as
					     not all hardware supports
					     64 bit addresses for consistent
					     allocations such descriptors. */

	struct device_dma_parameters *dma_parms;

	struct list_head	dma_pools;	/* dma pools (if dma'ble) */

	struct dma_coherent_mem	*dma_mem; /* internal for coherent mem
					     override */
	/* arch specific additions */
	struct dev_archdata	archdata;

	struct device_node	*of_node; /* associated device tree node */

	dev_t			devt;	/* dev_t, creates the sysfs "dev" */

	spinlock_t		devres_lock;
	struct list_head	devres_head;

	struct klist_node	knode_class;
	struct class		*class;
	const struct attribute_group **groups;	/* optional groups */

	void	(*release)(struct device *dev);
};

/* Get the wakeup routines, which depend on struct device */
#include <linux/pm_wakeup.h>

static inline const char *dev_name(const struct device *dev)
{
	/* Use the init name until the kobject becomes available */
	if (dev->init_name)
		return dev->init_name;

	return kobject_name(&dev->kobj);
}

extern int dev_set_name(struct device *dev, const char *name, ...)
			__attribute__((format(printf, 2, 3)));

#ifdef CONFIG_NUMA
static inline int dev_to_node(struct device *dev)
{
	return dev->numa_node;
}
static inline void set_dev_node(struct device *dev, int node)
{
	dev->numa_node = node;
}
#else
static inline int dev_to_node(struct device *dev)
{
	return -1;
}
static inline void set_dev_node(struct device *dev, int node)
{
}
#endif

static inline struct pm_subsys_data *dev_to_psd(struct device *dev)
{
	return dev ? dev->power.subsys_data : NULL;
}

static inline unsigned int dev_get_uevent_suppress(const struct device *dev)
{
	return dev->kobj.uevent_suppress;
}

static inline void dev_set_uevent_suppress(struct device *dev, int val)
{
	dev->kobj.uevent_suppress = val;
}

static inline int device_is_registered(struct device *dev)
{
	return dev->kobj.state_in_sysfs;
}

static inline void device_enable_async_suspend(struct device *dev)
{
	if (!dev->power.is_prepared)
		dev->power.async_suspend = true;
}

static inline void device_disable_async_suspend(struct device *dev)
{
	if (!dev->power.is_prepared)
		dev->power.async_suspend = false;
}

static inline bool device_async_suspend_enabled(struct device *dev)
{
	return !!dev->power.async_suspend;
}

static inline void device_lock(struct device *dev)
{
	mutex_lock(&dev->mutex);
}

static inline int device_trylock(struct device *dev)
{
	return mutex_trylock(&dev->mutex);
}

static inline void device_unlock(struct device *dev)
{
	mutex_unlock(&dev->mutex);
}

void driver_init(void);

/*
 * High level routines for use by the bus drivers
 */
extern int __must_check device_register(struct device *dev);
extern void device_unregister(struct device *dev);
extern void device_initialize(struct device *dev);
extern int __must_check device_add(struct device *dev);
extern void device_del(struct device *dev);
extern int device_for_each_child(struct device *dev, void *data,
		     int (*fn)(struct device *dev, void *data));
extern struct device *device_find_child(struct device *dev, void *data,
				int (*match)(struct device *dev, void *data));
extern int device_rename(struct device *dev, const char *new_name);
extern int device_move(struct device *dev, struct device *new_parent,
		       enum dpm_order dpm_order);
extern const char *device_get_devnode(struct device *dev,
				      mode_t *mode, const char **tmp);
extern void *dev_get_drvdata(const struct device *dev);
extern int dev_set_drvdata(struct device *dev, void *data);

/*
 * Root device objects for grouping under /sys/devices
 */
extern struct device *__root_device_register(const char *name,
					     struct module *owner);

/*
 * This is a macro to avoid include problems with THIS_MODULE,
 * just as per what is done for device_schedule_callback() above.
 */
#define root_device_register(name) \
	__root_device_register(name, THIS_MODULE)

extern void root_device_unregister(struct device *root);

static inline void *dev_get_platdata(const struct device *dev)
{
	return dev->platform_data;
}

/*
 * Manual binding of a device to driver. See drivers/base/bus.c
 * for information on use.
 */
extern int __must_check device_bind_driver(struct device *dev);
extern void device_release_driver(struct device *dev);
extern int  __must_check device_attach(struct device *dev);
extern int __must_check driver_attach(struct device_driver *drv);
extern int __must_check device_reprobe(struct device *dev);

/*
 * Easy functions for dynamically creating devices on the fly
 */
extern struct device *device_create_vargs(struct class *cls,
					  struct device *parent,
					  dev_t devt,
					  void *drvdata,
					  const char *fmt,
					  va_list vargs);
extern struct device *device_create(struct class *cls, struct device *parent,
				    dev_t devt, void *drvdata,
				    const char *fmt, ...)
				    __attribute__((format(printf, 5, 6)));
extern void device_destroy(struct class *cls, dev_t devt);

/*
 * Platform "fixup" functions - allow the platform to have their say
 * about devices and actions that the general device layer doesn't
 * know about.
 */
/* Notify platform of device discovery */
extern int (*platform_notify)(struct device *dev);

extern int (*platform_notify_remove)(struct device *dev);


/*
 * get_device - atomically increment the reference count for the device.
 *
 */
extern struct device *get_device(struct device *dev);
extern void put_device(struct device *dev);

extern void wait_for_device_probe(void);

#ifdef CONFIG_DEVTMPFS
extern int devtmpfs_create_node(struct device *dev);
extern int devtmpfs_delete_node(struct device *dev);
extern int devtmpfs_mount(const char *mntdir);
#else
static inline int devtmpfs_create_node(struct device *dev) { return 0; }
static inline int devtmpfs_delete_node(struct device *dev) { return 0; }
static inline int devtmpfs_mount(const char *mountpoint) { return 0; }
#endif

/* drivers/base/power/shutdown.c */
extern void device_shutdown(void);

/* debugging and troubleshooting/diagnostic helpers. */
extern const char *dev_driver_string(const struct device *dev);


#ifdef CONFIG_PRINTK

extern int __dev_printk(const char *level, const struct device *dev,
			struct va_format *vaf);
extern int dev_printk(const char *level, const struct device *dev,
		      const char *fmt, ...)
	__attribute__ ((format (printf, 3, 4)));
extern int dev_emerg(const struct device *dev, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
extern int dev_alert(const struct device *dev, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
extern int dev_crit(const struct device *dev, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
extern int dev_err(const struct device *dev, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
extern int dev_warn(const struct device *dev, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
extern int dev_notice(const struct device *dev, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
extern int _dev_info(const struct device *dev, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));

#else

static inline int __dev_printk(const char *level, const struct device *dev,
			       struct va_format *vaf)
	 { return 0; }
static inline int dev_printk(const char *level, const struct device *dev,
		      const char *fmt, ...)
	__attribute__ ((format (printf, 3, 4)));
static inline int dev_printk(const char *level, const struct device *dev,
		      const char *fmt, ...)
	 { return 0; }

static inline int dev_emerg(const struct device *dev, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
static inline int dev_emerg(const struct device *dev, const char *fmt, ...)
	{ return 0; }
static inline int dev_crit(const struct device *dev, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
static inline int dev_crit(const struct device *dev, const char *fmt, ...)
	{ return 0; }
static inline int dev_alert(const struct device *dev, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
static inline int dev_alert(const struct device *dev, const char *fmt, ...)
	{ return 0; }
static inline int dev_err(const struct device *dev, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
static inline int dev_err(const struct device *dev, const char *fmt, ...)
	{ return 0; }
static inline int dev_warn(const struct device *dev, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
static inline int dev_warn(const struct device *dev, const char *fmt, ...)
	{ return 0; }
static inline int dev_notice(const struct device *dev, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
static inline int dev_notice(const struct device *dev, const char *fmt, ...)
	{ return 0; }
static inline int _dev_info(const struct device *dev, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
static inline int _dev_info(const struct device *dev, const char *fmt, ...)
	{ return 0; }

#endif

/*
 * Stupid hackaround for existing uses of non-printk uses dev_info
 *
 * Note that the definition of dev_info below is actually _dev_info
 * and a macro is used to avoid redefining dev_info
 */

#define dev_info(dev, fmt, arg...) _dev_info(dev, fmt, ##arg)

#if defined(DEBUG)
#define dev_dbg(dev, format, arg...)		\
	dev_printk(KERN_DEBUG, dev, format, ##arg)
#elif defined(CONFIG_DYNAMIC_DEBUG)
#define dev_dbg(dev, format, ...)		     \
do {						     \
	dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
} while (0)
#else
#define dev_dbg(dev, format, arg...)				\
({								\
	if (0)							\
		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
	0;							\
})
#endif

#ifdef VERBOSE_DEBUG
#define dev_vdbg	dev_dbg
#else
#define dev_vdbg(dev, format, arg...)				\
({								\
	if (0)							\
		dev_printk(KERN_DEBUG, dev, format, ##arg);	\
	0;							\
})
#endif

/*
 * dev_WARN*() acts like dev_printk(), but with the key difference
 * of using a WARN/WARN_ON to get the message out, including the
 * file/line information and a backtrace.
 */
#define dev_WARN(dev, format, arg...) \
	WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg);

#define dev_WARN_ONCE(dev, condition, format, arg...) \
	WARN_ONCE(condition, "Device %s\n" format, \
			dev_driver_string(dev), ## arg)

/* Create alias, so I can be autoloaded. */
#define MODULE_ALIAS_CHARDEV(major,minor) \
	MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
#define MODULE_ALIAS_CHARDEV_MAJOR(major) \
	MODULE_ALIAS("char-major-" __stringify(major) "-*")

#ifdef CONFIG_SYSFS_DEPRECATED
extern long sysfs_deprecated;
#else
#define sysfs_deprecated 0
#endif

#endif /* _DEVICE_H_ */
OpenPOWER on IntegriCloud