forked from torvalds/linux
-
Notifications
You must be signed in to change notification settings - Fork 1
/
Copy pathinput.c
2135 lines (1753 loc) · 51.4 KB
/
input.c
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
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* The input core
*
* Copyright (c) 1999-2002 Vojtech Pavlik
*/
/*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*/
#define pr_fmt(fmt) KBUILD_BASENAME ": " fmt
#include <linux/init.h>
#include <linux/types.h>
#include <linux/input/mt.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/random.h>
#include <linux/major.h>
#include <linux/proc_fs.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/poll.h>
#include <linux/device.h>
#include <linux/mutex.h>
#include <linux/rcupdate.h>
#include "input-compat.h"
MODULE_AUTHOR("Vojtech Pavlik <[email protected]>");
MODULE_DESCRIPTION("Input core");
MODULE_LICENSE("GPL");
#define INPUT_DEVICES 256
static LIST_HEAD(input_dev_list);
static LIST_HEAD(input_handler_list);
/*
* input_mutex protects access to both input_dev_list and input_handler_list.
* This also causes input_[un]register_device and input_[un]register_handler
* be mutually exclusive which simplifies locking in drivers implementing
* input handlers.
*/
static DEFINE_MUTEX(input_mutex);
static struct input_handler *input_table[8];
static inline int is_event_supported(unsigned int code,
unsigned long *bm, unsigned int max)
{
return code <= max && test_bit(code, bm);
}
static int input_defuzz_abs_event(int value, int old_val, int fuzz)
{
if (fuzz) {
if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
return old_val;
if (value > old_val - fuzz && value < old_val + fuzz)
return (old_val * 3 + value) / 4;
if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
return (old_val + value) / 2;
}
return value;
}
/*
* Pass event first through all filters and then, if event has not been
* filtered out, through all open handles. This function is called with
* dev->event_lock held and interrupts disabled.
*/
static void input_pass_event(struct input_dev *dev,
unsigned int type, unsigned int code, int value)
{
struct input_handler *handler;
struct input_handle *handle;
rcu_read_lock();
handle = rcu_dereference(dev->grab);
if (handle)
handle->handler->event(handle, type, code, value);
else {
bool filtered = false;
list_for_each_entry_rcu(handle, &dev->h_list, d_node) {
if (!handle->open)
continue;
handler = handle->handler;
if (!handler->filter) {
if (filtered)
break;
handler->event(handle, type, code, value);
} else if (handler->filter(handle, type, code, value))
filtered = true;
}
}
rcu_read_unlock();
}
/*
* Generate software autorepeat event. Note that we take
* dev->event_lock here to avoid racing with input_event
* which may cause keys get "stuck".
*/
static void input_repeat_key(unsigned long data)
{
struct input_dev *dev = (void *) data;
unsigned long flags;
spin_lock_irqsave(&dev->event_lock, flags);
if (test_bit(dev->repeat_key, dev->key) &&
is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
input_pass_event(dev, EV_KEY, dev->repeat_key, 2);
if (dev->sync) {
/*
* Only send SYN_REPORT if we are not in a middle
* of driver parsing a new hardware packet.
* Otherwise assume that the driver will send
* SYN_REPORT once it's done.
*/
input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
}
if (dev->rep[REP_PERIOD])
mod_timer(&dev->timer, jiffies +
msecs_to_jiffies(dev->rep[REP_PERIOD]));
}
spin_unlock_irqrestore(&dev->event_lock, flags);
}
static void input_start_autorepeat(struct input_dev *dev, int code)
{
if (test_bit(EV_REP, dev->evbit) &&
dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
dev->timer.data) {
dev->repeat_key = code;
mod_timer(&dev->timer,
jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
}
}
static void input_stop_autorepeat(struct input_dev *dev)
{
del_timer(&dev->timer);
}
#define INPUT_IGNORE_EVENT 0
#define INPUT_PASS_TO_HANDLERS 1
#define INPUT_PASS_TO_DEVICE 2
#define INPUT_PASS_TO_ALL (INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
static int input_handle_abs_event(struct input_dev *dev,
unsigned int code, int *pval)
{
bool is_mt_event;
int *pold;
if (code == ABS_MT_SLOT) {
/*
* "Stage" the event; we'll flush it later, when we
* get actual touch data.
*/
if (*pval >= 0 && *pval < dev->mtsize)
dev->slot = *pval;
return INPUT_IGNORE_EVENT;
}
is_mt_event = code >= ABS_MT_FIRST && code <= ABS_MT_LAST;
if (!is_mt_event) {
pold = &dev->absinfo[code].value;
} else if (dev->mt) {
struct input_mt_slot *mtslot = &dev->mt[dev->slot];
pold = &mtslot->abs[code - ABS_MT_FIRST];
} else {
/*
* Bypass filtering for multi-touch events when
* not employing slots.
*/
pold = NULL;
}
if (pold) {
*pval = input_defuzz_abs_event(*pval, *pold,
dev->absinfo[code].fuzz);
if (*pold == *pval)
return INPUT_IGNORE_EVENT;
*pold = *pval;
}
/* Flush pending "slot" event */
if (is_mt_event && dev->slot != input_abs_get_val(dev, ABS_MT_SLOT)) {
input_abs_set_val(dev, ABS_MT_SLOT, dev->slot);
input_pass_event(dev, EV_ABS, ABS_MT_SLOT, dev->slot);
}
return INPUT_PASS_TO_HANDLERS;
}
static void input_handle_event(struct input_dev *dev,
unsigned int type, unsigned int code, int value)
{
int disposition = INPUT_IGNORE_EVENT;
switch (type) {
case EV_SYN:
switch (code) {
case SYN_CONFIG:
disposition = INPUT_PASS_TO_ALL;
break;
case SYN_REPORT:
if (!dev->sync) {
dev->sync = true;
disposition = INPUT_PASS_TO_HANDLERS;
}
break;
case SYN_MT_REPORT:
dev->sync = false;
disposition = INPUT_PASS_TO_HANDLERS;
break;
}
break;
case EV_KEY:
if (is_event_supported(code, dev->keybit, KEY_MAX) &&
!!test_bit(code, dev->key) != value) {
if (value != 2) {
__change_bit(code, dev->key);
if (value)
input_start_autorepeat(dev, code);
else
input_stop_autorepeat(dev);
}
disposition = INPUT_PASS_TO_HANDLERS;
}
break;
case EV_SW:
if (is_event_supported(code, dev->swbit, SW_MAX) &&
!!test_bit(code, dev->sw) != value) {
__change_bit(code, dev->sw);
disposition = INPUT_PASS_TO_HANDLERS;
}
break;
case EV_ABS:
if (is_event_supported(code, dev->absbit, ABS_MAX))
disposition = input_handle_abs_event(dev, code, &value);
break;
case EV_REL:
if (is_event_supported(code, dev->relbit, REL_MAX) && value)
disposition = INPUT_PASS_TO_HANDLERS;
break;
case EV_MSC:
if (is_event_supported(code, dev->mscbit, MSC_MAX))
disposition = INPUT_PASS_TO_ALL;
break;
case EV_LED:
if (is_event_supported(code, dev->ledbit, LED_MAX) &&
!!test_bit(code, dev->led) != value) {
__change_bit(code, dev->led);
disposition = INPUT_PASS_TO_ALL;
}
break;
case EV_SND:
if (is_event_supported(code, dev->sndbit, SND_MAX)) {
if (!!test_bit(code, dev->snd) != !!value)
__change_bit(code, dev->snd);
disposition = INPUT_PASS_TO_ALL;
}
break;
case EV_REP:
if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
dev->rep[code] = value;
disposition = INPUT_PASS_TO_ALL;
}
break;
case EV_FF:
if (value >= 0)
disposition = INPUT_PASS_TO_ALL;
break;
case EV_PWR:
disposition = INPUT_PASS_TO_ALL;
break;
}
if (disposition != INPUT_IGNORE_EVENT && type != EV_SYN)
dev->sync = false;
if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
dev->event(dev, type, code, value);
if (disposition & INPUT_PASS_TO_HANDLERS)
input_pass_event(dev, type, code, value);
}
/**
* input_event() - report new input event
* @dev: device that generated the event
* @type: type of the event
* @code: event code
* @value: value of the event
*
* This function should be used by drivers implementing various input
* devices to report input events. See also input_inject_event().
*
* NOTE: input_event() may be safely used right after input device was
* allocated with input_allocate_device(), even before it is registered
* with input_register_device(), but the event will not reach any of the
* input handlers. Such early invocation of input_event() may be used
* to 'seed' initial state of a switch or initial position of absolute
* axis, etc.
*/
void input_event(struct input_dev *dev,
unsigned int type, unsigned int code, int value)
{
unsigned long flags;
if (is_event_supported(type, dev->evbit, EV_MAX)) {
spin_lock_irqsave(&dev->event_lock, flags);
add_input_randomness(type, code, value);
input_handle_event(dev, type, code, value);
spin_unlock_irqrestore(&dev->event_lock, flags);
}
}
EXPORT_SYMBOL(input_event);
/**
* input_inject_event() - send input event from input handler
* @handle: input handle to send event through
* @type: type of the event
* @code: event code
* @value: value of the event
*
* Similar to input_event() but will ignore event if device is
* "grabbed" and handle injecting event is not the one that owns
* the device.
*/
void input_inject_event(struct input_handle *handle,
unsigned int type, unsigned int code, int value)
{
struct input_dev *dev = handle->dev;
struct input_handle *grab;
unsigned long flags;
if (is_event_supported(type, dev->evbit, EV_MAX)) {
spin_lock_irqsave(&dev->event_lock, flags);
rcu_read_lock();
grab = rcu_dereference(dev->grab);
if (!grab || grab == handle)
input_handle_event(dev, type, code, value);
rcu_read_unlock();
spin_unlock_irqrestore(&dev->event_lock, flags);
}
}
EXPORT_SYMBOL(input_inject_event);
/**
* input_alloc_absinfo - allocates array of input_absinfo structs
* @dev: the input device emitting absolute events
*
* If the absinfo struct the caller asked for is already allocated, this
* functions will not do anything.
*/
void input_alloc_absinfo(struct input_dev *dev)
{
if (!dev->absinfo)
dev->absinfo = kcalloc(ABS_CNT, sizeof(struct input_absinfo),
GFP_KERNEL);
WARN(!dev->absinfo, "%s(): kcalloc() failed?\n", __func__);
}
EXPORT_SYMBOL(input_alloc_absinfo);
void input_set_abs_params(struct input_dev *dev, unsigned int axis,
int min, int max, int fuzz, int flat)
{
struct input_absinfo *absinfo;
input_alloc_absinfo(dev);
if (!dev->absinfo)
return;
absinfo = &dev->absinfo[axis];
absinfo->minimum = min;
absinfo->maximum = max;
absinfo->fuzz = fuzz;
absinfo->flat = flat;
dev->absbit[BIT_WORD(axis)] |= BIT_MASK(axis);
}
EXPORT_SYMBOL(input_set_abs_params);
/**
* input_grab_device - grabs device for exclusive use
* @handle: input handle that wants to own the device
*
* When a device is grabbed by an input handle all events generated by
* the device are delivered only to this handle. Also events injected
* by other input handles are ignored while device is grabbed.
*/
int input_grab_device(struct input_handle *handle)
{
struct input_dev *dev = handle->dev;
int retval;
retval = mutex_lock_interruptible(&dev->mutex);
if (retval)
return retval;
if (dev->grab) {
retval = -EBUSY;
goto out;
}
rcu_assign_pointer(dev->grab, handle);
synchronize_rcu();
out:
mutex_unlock(&dev->mutex);
return retval;
}
EXPORT_SYMBOL(input_grab_device);
static void __input_release_device(struct input_handle *handle)
{
struct input_dev *dev = handle->dev;
if (dev->grab == handle) {
rcu_assign_pointer(dev->grab, NULL);
/* Make sure input_pass_event() notices that grab is gone */
synchronize_rcu();
list_for_each_entry(handle, &dev->h_list, d_node)
if (handle->open && handle->handler->start)
handle->handler->start(handle);
}
}
/**
* input_release_device - release previously grabbed device
* @handle: input handle that owns the device
*
* Releases previously grabbed device so that other input handles can
* start receiving input events. Upon release all handlers attached
* to the device have their start() method called so they have a change
* to synchronize device state with the rest of the system.
*/
void input_release_device(struct input_handle *handle)
{
struct input_dev *dev = handle->dev;
mutex_lock(&dev->mutex);
__input_release_device(handle);
mutex_unlock(&dev->mutex);
}
EXPORT_SYMBOL(input_release_device);
/**
* input_open_device - open input device
* @handle: handle through which device is being accessed
*
* This function should be called by input handlers when they
* want to start receive events from given input device.
*/
int input_open_device(struct input_handle *handle)
{
struct input_dev *dev = handle->dev;
int retval;
retval = mutex_lock_interruptible(&dev->mutex);
if (retval)
return retval;
if (dev->going_away) {
retval = -ENODEV;
goto out;
}
handle->open++;
if (!dev->users++ && dev->open)
retval = dev->open(dev);
if (retval) {
dev->users--;
if (!--handle->open) {
/*
* Make sure we are not delivering any more events
* through this handle
*/
synchronize_rcu();
}
}
out:
mutex_unlock(&dev->mutex);
return retval;
}
EXPORT_SYMBOL(input_open_device);
int input_flush_device(struct input_handle *handle, struct file *file)
{
struct input_dev *dev = handle->dev;
int retval;
retval = mutex_lock_interruptible(&dev->mutex);
if (retval)
return retval;
if (dev->flush)
retval = dev->flush(dev, file);
mutex_unlock(&dev->mutex);
return retval;
}
EXPORT_SYMBOL(input_flush_device);
/**
* input_close_device - close input device
* @handle: handle through which device is being accessed
*
* This function should be called by input handlers when they
* want to stop receive events from given input device.
*/
void input_close_device(struct input_handle *handle)
{
struct input_dev *dev = handle->dev;
mutex_lock(&dev->mutex);
__input_release_device(handle);
if (!--dev->users && dev->close)
dev->close(dev);
if (!--handle->open) {
/*
* synchronize_rcu() makes sure that input_pass_event()
* completed and that no more input events are delivered
* through this handle
*/
synchronize_rcu();
}
mutex_unlock(&dev->mutex);
}
EXPORT_SYMBOL(input_close_device);
/*
* Simulate keyup events for all keys that are marked as pressed.
* The function must be called with dev->event_lock held.
*/
static void input_dev_release_keys(struct input_dev *dev)
{
int code;
if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
for (code = 0; code <= KEY_MAX; code++) {
if (is_event_supported(code, dev->keybit, KEY_MAX) &&
__test_and_clear_bit(code, dev->key)) {
input_pass_event(dev, EV_KEY, code, 0);
}
}
input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
}
}
/*
* Prepare device for unregistering
*/
static void input_disconnect_device(struct input_dev *dev)
{
struct input_handle *handle;
/*
* Mark device as going away. Note that we take dev->mutex here
* not to protect access to dev->going_away but rather to ensure
* that there are no threads in the middle of input_open_device()
*/
mutex_lock(&dev->mutex);
dev->going_away = true;
mutex_unlock(&dev->mutex);
spin_lock_irq(&dev->event_lock);
/*
* Simulate keyup events for all pressed keys so that handlers
* are not left with "stuck" keys. The driver may continue
* generate events even after we done here but they will not
* reach any handlers.
*/
input_dev_release_keys(dev);
list_for_each_entry(handle, &dev->h_list, d_node)
handle->open = 0;
spin_unlock_irq(&dev->event_lock);
}
/**
* input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
* @ke: keymap entry containing scancode to be converted.
* @scancode: pointer to the location where converted scancode should
* be stored.
*
* This function is used to convert scancode stored in &struct keymap_entry
* into scalar form understood by legacy keymap handling methods. These
* methods expect scancodes to be represented as 'unsigned int'.
*/
int input_scancode_to_scalar(const struct input_keymap_entry *ke,
unsigned int *scancode)
{
switch (ke->len) {
case 1:
*scancode = *((u8 *)ke->scancode);
break;
case 2:
*scancode = *((u16 *)ke->scancode);
break;
case 4:
*scancode = *((u32 *)ke->scancode);
break;
default:
return -EINVAL;
}
return 0;
}
EXPORT_SYMBOL(input_scancode_to_scalar);
/*
* Those routines handle the default case where no [gs]etkeycode() is
* defined. In this case, an array indexed by the scancode is used.
*/
static unsigned int input_fetch_keycode(struct input_dev *dev,
unsigned int index)
{
switch (dev->keycodesize) {
case 1:
return ((u8 *)dev->keycode)[index];
case 2:
return ((u16 *)dev->keycode)[index];
default:
return ((u32 *)dev->keycode)[index];
}
}
static int input_default_getkeycode(struct input_dev *dev,
struct input_keymap_entry *ke)
{
unsigned int index;
int error;
if (!dev->keycodesize)
return -EINVAL;
if (ke->flags & INPUT_KEYMAP_BY_INDEX)
index = ke->index;
else {
error = input_scancode_to_scalar(ke, &index);
if (error)
return error;
}
if (index >= dev->keycodemax)
return -EINVAL;
ke->keycode = input_fetch_keycode(dev, index);
ke->index = index;
ke->len = sizeof(index);
memcpy(ke->scancode, &index, sizeof(index));
return 0;
}
static int input_default_setkeycode(struct input_dev *dev,
const struct input_keymap_entry *ke,
unsigned int *old_keycode)
{
unsigned int index;
int error;
int i;
if (!dev->keycodesize)
return -EINVAL;
if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
index = ke->index;
} else {
error = input_scancode_to_scalar(ke, &index);
if (error)
return error;
}
if (index >= dev->keycodemax)
return -EINVAL;
if (dev->keycodesize < sizeof(ke->keycode) &&
(ke->keycode >> (dev->keycodesize * 8)))
return -EINVAL;
switch (dev->keycodesize) {
case 1: {
u8 *k = (u8 *)dev->keycode;
*old_keycode = k[index];
k[index] = ke->keycode;
break;
}
case 2: {
u16 *k = (u16 *)dev->keycode;
*old_keycode = k[index];
k[index] = ke->keycode;
break;
}
default: {
u32 *k = (u32 *)dev->keycode;
*old_keycode = k[index];
k[index] = ke->keycode;
break;
}
}
__clear_bit(*old_keycode, dev->keybit);
__set_bit(ke->keycode, dev->keybit);
for (i = 0; i < dev->keycodemax; i++) {
if (input_fetch_keycode(dev, i) == *old_keycode) {
__set_bit(*old_keycode, dev->keybit);
break; /* Setting the bit twice is useless, so break */
}
}
return 0;
}
/**
* input_get_keycode - retrieve keycode currently mapped to a given scancode
* @dev: input device which keymap is being queried
* @ke: keymap entry
*
* This function should be called by anyone interested in retrieving current
* keymap. Presently evdev handlers use it.
*/
int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
{
unsigned long flags;
int retval;
spin_lock_irqsave(&dev->event_lock, flags);
retval = dev->getkeycode(dev, ke);
spin_unlock_irqrestore(&dev->event_lock, flags);
return retval;
}
EXPORT_SYMBOL(input_get_keycode);
/**
* input_set_keycode - attribute a keycode to a given scancode
* @dev: input device which keymap is being updated
* @ke: new keymap entry
*
* This function should be called by anyone needing to update current
* keymap. Presently keyboard and evdev handlers use it.
*/
int input_set_keycode(struct input_dev *dev,
const struct input_keymap_entry *ke)
{
unsigned long flags;
unsigned int old_keycode;
int retval;
if (ke->keycode > KEY_MAX)
return -EINVAL;
spin_lock_irqsave(&dev->event_lock, flags);
retval = dev->setkeycode(dev, ke, &old_keycode);
if (retval)
goto out;
/* Make sure KEY_RESERVED did not get enabled. */
__clear_bit(KEY_RESERVED, dev->keybit);
/*
* Simulate keyup event if keycode is not present
* in the keymap anymore
*/
if (test_bit(EV_KEY, dev->evbit) &&
!is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
__test_and_clear_bit(old_keycode, dev->key)) {
input_pass_event(dev, EV_KEY, old_keycode, 0);
if (dev->sync)
input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
}
out:
spin_unlock_irqrestore(&dev->event_lock, flags);
return retval;
}
EXPORT_SYMBOL(input_set_keycode);
#define MATCH_BIT(bit, max) \
for (i = 0; i < BITS_TO_LONGS(max); i++) \
if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \
break; \
if (i != BITS_TO_LONGS(max)) \
continue;
static const struct input_device_id *input_match_device(struct input_handler *handler,
struct input_dev *dev)
{
const struct input_device_id *id;
int i;
for (id = handler->id_table; id->flags || id->driver_info; id++) {
if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
if (id->bustype != dev->id.bustype)
continue;
if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
if (id->vendor != dev->id.vendor)
continue;
if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
if (id->product != dev->id.product)
continue;
if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
if (id->version != dev->id.version)
continue;
MATCH_BIT(evbit, EV_MAX);
MATCH_BIT(keybit, KEY_MAX);
MATCH_BIT(relbit, REL_MAX);
MATCH_BIT(absbit, ABS_MAX);
MATCH_BIT(mscbit, MSC_MAX);
MATCH_BIT(ledbit, LED_MAX);
MATCH_BIT(sndbit, SND_MAX);
MATCH_BIT(ffbit, FF_MAX);
MATCH_BIT(swbit, SW_MAX);
if (!handler->match || handler->match(handler, dev))
return id;
}
return NULL;
}
static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
{
const struct input_device_id *id;
int error;
id = input_match_device(handler, dev);
if (!id)
return -ENODEV;
error = handler->connect(handler, dev, id);
if (error && error != -ENODEV)
pr_err("failed to attach handler %s to device %s, error: %d\n",
handler->name, kobject_name(&dev->dev.kobj), error);
return error;
}
#ifdef CONFIG_COMPAT
static int input_bits_to_string(char *buf, int buf_size,
unsigned long bits, bool skip_empty)
{
int len = 0;
if (INPUT_COMPAT_TEST) {
u32 dword = bits >> 32;
if (dword || !skip_empty)
len += snprintf(buf, buf_size, "%x ", dword);
dword = bits & 0xffffffffUL;
if (dword || !skip_empty || len)
len += snprintf(buf + len, max(buf_size - len, 0),
"%x", dword);
} else {
if (bits || !skip_empty)
len += snprintf(buf, buf_size, "%lx", bits);
}
return len;
}
#else /* !CONFIG_COMPAT */
static int input_bits_to_string(char *buf, int buf_size,
unsigned long bits, bool skip_empty)
{
return bits || !skip_empty ?
snprintf(buf, buf_size, "%lx", bits) : 0;
}
#endif
#ifdef CONFIG_PROC_FS
static struct proc_dir_entry *proc_bus_input_dir;
static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
static int input_devices_state;
static inline void input_wakeup_procfs_readers(void)
{
input_devices_state++;
wake_up(&input_devices_poll_wait);
}
static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
{
poll_wait(file, &input_devices_poll_wait, wait);
if (file->f_version != input_devices_state) {
file->f_version = input_devices_state;
return POLLIN | POLLRDNORM;
}
return 0;
}
union input_seq_state {
struct {
unsigned short pos;
bool mutex_acquired;
};
void *p;
};
static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
{
union input_seq_state *state = (union input_seq_state *)&seq->private;
int error;
/* We need to fit into seq->private pointer */
BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
error = mutex_lock_interruptible(&input_mutex);
if (error) {
state->mutex_acquired = false;
return ERR_PTR(error);
}
state->mutex_acquired = true;
return seq_list_start(&input_dev_list, *pos);
}
static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
return seq_list_next(v, &input_dev_list, pos);