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Input: add safety guards to input_set_keycode()
[GitHub/MotorolaMobilityLLC/kernel-slsi.git] / drivers / input / input.c
1 /*
2 * The input core
3 *
4 * Copyright (c) 1999-2002 Vojtech Pavlik
5 */
6
7 /*
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 as published by
10 * the Free Software Foundation.
11 */
12
13 #define pr_fmt(fmt) KBUILD_BASENAME ": " fmt
14
15 #include <linux/init.h>
16 #include <linux/types.h>
17 #include <linux/idr.h>
18 #include <linux/input/mt.h>
19 #include <linux/module.h>
20 #include <linux/slab.h>
21 #include <linux/random.h>
22 #include <linux/major.h>
23 #include <linux/proc_fs.h>
24 #include <linux/sched.h>
25 #include <linux/seq_file.h>
26 #include <linux/poll.h>
27 #include <linux/device.h>
28 #include <linux/mutex.h>
29 #include <linux/rcupdate.h>
30 #include "input-compat.h"
31
32 MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
33 MODULE_DESCRIPTION("Input core");
34 MODULE_LICENSE("GPL");
35
36 #define INPUT_MAX_CHAR_DEVICES 1024
37 #define INPUT_FIRST_DYNAMIC_DEV 256
38 static DEFINE_IDA(input_ida);
39
40 static LIST_HEAD(input_dev_list);
41 static LIST_HEAD(input_handler_list);
42
43 /*
44 * input_mutex protects access to both input_dev_list and input_handler_list.
45 * This also causes input_[un]register_device and input_[un]register_handler
46 * be mutually exclusive which simplifies locking in drivers implementing
47 * input handlers.
48 */
49 static DEFINE_MUTEX(input_mutex);
50
51 static const struct input_value input_value_sync = { EV_SYN, SYN_REPORT, 1 };
52
53 static inline int is_event_supported(unsigned int code,
54 unsigned long *bm, unsigned int max)
55 {
56 return code <= max && test_bit(code, bm);
57 }
58
59 static int input_defuzz_abs_event(int value, int old_val, int fuzz)
60 {
61 if (fuzz) {
62 if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
63 return old_val;
64
65 if (value > old_val - fuzz && value < old_val + fuzz)
66 return (old_val * 3 + value) / 4;
67
68 if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
69 return (old_val + value) / 2;
70 }
71
72 return value;
73 }
74
75 static void input_start_autorepeat(struct input_dev *dev, int code)
76 {
77 if (test_bit(EV_REP, dev->evbit) &&
78 dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
79 dev->timer.data) {
80 dev->repeat_key = code;
81 mod_timer(&dev->timer,
82 jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
83 }
84 }
85
86 static void input_stop_autorepeat(struct input_dev *dev)
87 {
88 del_timer(&dev->timer);
89 }
90
91 /*
92 * Pass event first through all filters and then, if event has not been
93 * filtered out, through all open handles. This function is called with
94 * dev->event_lock held and interrupts disabled.
95 */
96 static unsigned int input_to_handler(struct input_handle *handle,
97 struct input_value *vals, unsigned int count)
98 {
99 struct input_handler *handler = handle->handler;
100 struct input_value *end = vals;
101 struct input_value *v;
102
103 if (handler->filter) {
104 for (v = vals; v != vals + count; v++) {
105 if (handler->filter(handle, v->type, v->code, v->value))
106 continue;
107 if (end != v)
108 *end = *v;
109 end++;
110 }
111 count = end - vals;
112 }
113
114 if (!count)
115 return 0;
116
117 if (handler->events)
118 handler->events(handle, vals, count);
119 else if (handler->event)
120 for (v = vals; v != vals + count; v++)
121 handler->event(handle, v->type, v->code, v->value);
122
123 return count;
124 }
125
126 /*
127 * Pass values first through all filters and then, if event has not been
128 * filtered out, through all open handles. This function is called with
129 * dev->event_lock held and interrupts disabled.
130 */
131 static void input_pass_values(struct input_dev *dev,
132 struct input_value *vals, unsigned int count)
133 {
134 struct input_handle *handle;
135 struct input_value *v;
136
137 if (!count)
138 return;
139
140 rcu_read_lock();
141
142 handle = rcu_dereference(dev->grab);
143 if (handle) {
144 count = input_to_handler(handle, vals, count);
145 } else {
146 list_for_each_entry_rcu(handle, &dev->h_list, d_node)
147 if (handle->open) {
148 count = input_to_handler(handle, vals, count);
149 if (!count)
150 break;
151 }
152 }
153
154 rcu_read_unlock();
155
156 /* trigger auto repeat for key events */
157 if (test_bit(EV_REP, dev->evbit) && test_bit(EV_KEY, dev->evbit)) {
158 for (v = vals; v != vals + count; v++) {
159 if (v->type == EV_KEY && v->value != 2) {
160 if (v->value)
161 input_start_autorepeat(dev, v->code);
162 else
163 input_stop_autorepeat(dev);
164 }
165 }
166 }
167 }
168
169 static void input_pass_event(struct input_dev *dev,
170 unsigned int type, unsigned int code, int value)
171 {
172 struct input_value vals[] = { { type, code, value } };
173
174 input_pass_values(dev, vals, ARRAY_SIZE(vals));
175 }
176
177 /*
178 * Generate software autorepeat event. Note that we take
179 * dev->event_lock here to avoid racing with input_event
180 * which may cause keys get "stuck".
181 */
182 static void input_repeat_key(unsigned long data)
183 {
184 struct input_dev *dev = (void *) data;
185 unsigned long flags;
186
187 spin_lock_irqsave(&dev->event_lock, flags);
188
189 if (test_bit(dev->repeat_key, dev->key) &&
190 is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
191 struct input_value vals[] = {
192 { EV_KEY, dev->repeat_key, 2 },
193 input_value_sync
194 };
195
196 input_pass_values(dev, vals, ARRAY_SIZE(vals));
197
198 if (dev->rep[REP_PERIOD])
199 mod_timer(&dev->timer, jiffies +
200 msecs_to_jiffies(dev->rep[REP_PERIOD]));
201 }
202
203 spin_unlock_irqrestore(&dev->event_lock, flags);
204 }
205
206 #define INPUT_IGNORE_EVENT 0
207 #define INPUT_PASS_TO_HANDLERS 1
208 #define INPUT_PASS_TO_DEVICE 2
209 #define INPUT_SLOT 4
210 #define INPUT_FLUSH 8
211 #define INPUT_PASS_TO_ALL (INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
212
213 static int input_handle_abs_event(struct input_dev *dev,
214 unsigned int code, int *pval)
215 {
216 struct input_mt *mt = dev->mt;
217 bool is_mt_event;
218 int *pold;
219
220 if (code == ABS_MT_SLOT) {
221 /*
222 * "Stage" the event; we'll flush it later, when we
223 * get actual touch data.
224 */
225 if (mt && *pval >= 0 && *pval < mt->num_slots)
226 mt->slot = *pval;
227
228 return INPUT_IGNORE_EVENT;
229 }
230
231 is_mt_event = input_is_mt_value(code);
232
233 if (!is_mt_event) {
234 pold = &dev->absinfo[code].value;
235 } else if (mt) {
236 pold = &mt->slots[mt->slot].abs[code - ABS_MT_FIRST];
237 } else {
238 /*
239 * Bypass filtering for multi-touch events when
240 * not employing slots.
241 */
242 pold = NULL;
243 }
244
245 if (pold) {
246 *pval = input_defuzz_abs_event(*pval, *pold,
247 dev->absinfo[code].fuzz);
248 if (*pold == *pval)
249 return INPUT_IGNORE_EVENT;
250
251 *pold = *pval;
252 }
253
254 /* Flush pending "slot" event */
255 if (is_mt_event && mt && mt->slot != input_abs_get_val(dev, ABS_MT_SLOT)) {
256 input_abs_set_val(dev, ABS_MT_SLOT, mt->slot);
257 return INPUT_PASS_TO_HANDLERS | INPUT_SLOT;
258 }
259
260 return INPUT_PASS_TO_HANDLERS;
261 }
262
263 static int input_get_disposition(struct input_dev *dev,
264 unsigned int type, unsigned int code, int *pval)
265 {
266 int disposition = INPUT_IGNORE_EVENT;
267 int value = *pval;
268
269 switch (type) {
270
271 case EV_SYN:
272 switch (code) {
273 case SYN_CONFIG:
274 disposition = INPUT_PASS_TO_ALL;
275 break;
276
277 case SYN_REPORT:
278 disposition = INPUT_PASS_TO_HANDLERS | INPUT_FLUSH;
279 break;
280 case SYN_MT_REPORT:
281 disposition = INPUT_PASS_TO_HANDLERS;
282 break;
283 }
284 break;
285
286 case EV_KEY:
287 if (is_event_supported(code, dev->keybit, KEY_MAX)) {
288
289 /* auto-repeat bypasses state updates */
290 if (value == 2) {
291 disposition = INPUT_PASS_TO_HANDLERS;
292 break;
293 }
294
295 if (!!test_bit(code, dev->key) != !!value) {
296
297 __change_bit(code, dev->key);
298 disposition = INPUT_PASS_TO_HANDLERS;
299 }
300 }
301 break;
302
303 case EV_SW:
304 if (is_event_supported(code, dev->swbit, SW_MAX) &&
305 !!test_bit(code, dev->sw) != !!value) {
306
307 __change_bit(code, dev->sw);
308 disposition = INPUT_PASS_TO_HANDLERS;
309 }
310 break;
311
312 case EV_ABS:
313 if (is_event_supported(code, dev->absbit, ABS_MAX))
314 disposition = input_handle_abs_event(dev, code, &value);
315
316 break;
317
318 case EV_REL:
319 if (is_event_supported(code, dev->relbit, REL_MAX) && value)
320 disposition = INPUT_PASS_TO_HANDLERS;
321
322 break;
323
324 case EV_MSC:
325 if (is_event_supported(code, dev->mscbit, MSC_MAX))
326 disposition = INPUT_PASS_TO_ALL;
327
328 break;
329
330 case EV_LED:
331 if (is_event_supported(code, dev->ledbit, LED_MAX) &&
332 !!test_bit(code, dev->led) != !!value) {
333
334 __change_bit(code, dev->led);
335 disposition = INPUT_PASS_TO_ALL;
336 }
337 break;
338
339 case EV_SND:
340 if (is_event_supported(code, dev->sndbit, SND_MAX)) {
341
342 if (!!test_bit(code, dev->snd) != !!value)
343 __change_bit(code, dev->snd);
344 disposition = INPUT_PASS_TO_ALL;
345 }
346 break;
347
348 case EV_REP:
349 if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
350 dev->rep[code] = value;
351 disposition = INPUT_PASS_TO_ALL;
352 }
353 break;
354
355 case EV_FF:
356 if (value >= 0)
357 disposition = INPUT_PASS_TO_ALL;
358 break;
359
360 case EV_PWR:
361 disposition = INPUT_PASS_TO_ALL;
362 break;
363 }
364
365 *pval = value;
366 return disposition;
367 }
368
369 static void input_handle_event(struct input_dev *dev,
370 unsigned int type, unsigned int code, int value)
371 {
372 int disposition = input_get_disposition(dev, type, code, &value);
373
374 if (disposition != INPUT_IGNORE_EVENT && type != EV_SYN)
375 add_input_randomness(type, code, value);
376
377 if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
378 dev->event(dev, type, code, value);
379
380 if (!dev->vals)
381 return;
382
383 if (disposition & INPUT_PASS_TO_HANDLERS) {
384 struct input_value *v;
385
386 if (disposition & INPUT_SLOT) {
387 v = &dev->vals[dev->num_vals++];
388 v->type = EV_ABS;
389 v->code = ABS_MT_SLOT;
390 v->value = dev->mt->slot;
391 }
392
393 v = &dev->vals[dev->num_vals++];
394 v->type = type;
395 v->code = code;
396 v->value = value;
397 }
398
399 if (disposition & INPUT_FLUSH) {
400 if (dev->num_vals >= 2)
401 input_pass_values(dev, dev->vals, dev->num_vals);
402 dev->num_vals = 0;
403 } else if (dev->num_vals >= dev->max_vals - 2) {
404 dev->vals[dev->num_vals++] = input_value_sync;
405 input_pass_values(dev, dev->vals, dev->num_vals);
406 dev->num_vals = 0;
407 }
408
409 }
410
411 /**
412 * input_event() - report new input event
413 * @dev: device that generated the event
414 * @type: type of the event
415 * @code: event code
416 * @value: value of the event
417 *
418 * This function should be used by drivers implementing various input
419 * devices to report input events. See also input_inject_event().
420 *
421 * NOTE: input_event() may be safely used right after input device was
422 * allocated with input_allocate_device(), even before it is registered
423 * with input_register_device(), but the event will not reach any of the
424 * input handlers. Such early invocation of input_event() may be used
425 * to 'seed' initial state of a switch or initial position of absolute
426 * axis, etc.
427 */
428 void input_event(struct input_dev *dev,
429 unsigned int type, unsigned int code, int value)
430 {
431 unsigned long flags;
432
433 if (is_event_supported(type, dev->evbit, EV_MAX)) {
434
435 spin_lock_irqsave(&dev->event_lock, flags);
436 input_handle_event(dev, type, code, value);
437 spin_unlock_irqrestore(&dev->event_lock, flags);
438 }
439 }
440 EXPORT_SYMBOL(input_event);
441
442 /**
443 * input_inject_event() - send input event from input handler
444 * @handle: input handle to send event through
445 * @type: type of the event
446 * @code: event code
447 * @value: value of the event
448 *
449 * Similar to input_event() but will ignore event if device is
450 * "grabbed" and handle injecting event is not the one that owns
451 * the device.
452 */
453 void input_inject_event(struct input_handle *handle,
454 unsigned int type, unsigned int code, int value)
455 {
456 struct input_dev *dev = handle->dev;
457 struct input_handle *grab;
458 unsigned long flags;
459
460 if (is_event_supported(type, dev->evbit, EV_MAX)) {
461 spin_lock_irqsave(&dev->event_lock, flags);
462
463 rcu_read_lock();
464 grab = rcu_dereference(dev->grab);
465 if (!grab || grab == handle)
466 input_handle_event(dev, type, code, value);
467 rcu_read_unlock();
468
469 spin_unlock_irqrestore(&dev->event_lock, flags);
470 }
471 }
472 EXPORT_SYMBOL(input_inject_event);
473
474 /**
475 * input_alloc_absinfo - allocates array of input_absinfo structs
476 * @dev: the input device emitting absolute events
477 *
478 * If the absinfo struct the caller asked for is already allocated, this
479 * functions will not do anything.
480 */
481 void input_alloc_absinfo(struct input_dev *dev)
482 {
483 if (dev->absinfo)
484 return;
485
486 dev->absinfo = kcalloc(ABS_CNT, sizeof(*dev->absinfo), GFP_KERNEL);
487 if (!dev->absinfo) {
488 dev_err(dev->dev.parent ?: &dev->dev,
489 "%s: unable to allocate memory\n", __func__);
490 /*
491 * We will handle this allocation failure in
492 * input_register_device() when we refuse to register input
493 * device with ABS bits but without absinfo.
494 */
495 }
496 }
497 EXPORT_SYMBOL(input_alloc_absinfo);
498
499 void input_set_abs_params(struct input_dev *dev, unsigned int axis,
500 int min, int max, int fuzz, int flat)
501 {
502 struct input_absinfo *absinfo;
503
504 input_alloc_absinfo(dev);
505 if (!dev->absinfo)
506 return;
507
508 absinfo = &dev->absinfo[axis];
509 absinfo->minimum = min;
510 absinfo->maximum = max;
511 absinfo->fuzz = fuzz;
512 absinfo->flat = flat;
513
514 __set_bit(EV_ABS, dev->evbit);
515 __set_bit(axis, dev->absbit);
516 }
517 EXPORT_SYMBOL(input_set_abs_params);
518
519
520 /**
521 * input_grab_device - grabs device for exclusive use
522 * @handle: input handle that wants to own the device
523 *
524 * When a device is grabbed by an input handle all events generated by
525 * the device are delivered only to this handle. Also events injected
526 * by other input handles are ignored while device is grabbed.
527 */
528 int input_grab_device(struct input_handle *handle)
529 {
530 struct input_dev *dev = handle->dev;
531 int retval;
532
533 retval = mutex_lock_interruptible(&dev->mutex);
534 if (retval)
535 return retval;
536
537 if (dev->grab) {
538 retval = -EBUSY;
539 goto out;
540 }
541
542 rcu_assign_pointer(dev->grab, handle);
543
544 out:
545 mutex_unlock(&dev->mutex);
546 return retval;
547 }
548 EXPORT_SYMBOL(input_grab_device);
549
550 static void __input_release_device(struct input_handle *handle)
551 {
552 struct input_dev *dev = handle->dev;
553 struct input_handle *grabber;
554
555 grabber = rcu_dereference_protected(dev->grab,
556 lockdep_is_held(&dev->mutex));
557 if (grabber == handle) {
558 rcu_assign_pointer(dev->grab, NULL);
559 /* Make sure input_pass_event() notices that grab is gone */
560 synchronize_rcu();
561
562 list_for_each_entry(handle, &dev->h_list, d_node)
563 if (handle->open && handle->handler->start)
564 handle->handler->start(handle);
565 }
566 }
567
568 /**
569 * input_release_device - release previously grabbed device
570 * @handle: input handle that owns the device
571 *
572 * Releases previously grabbed device so that other input handles can
573 * start receiving input events. Upon release all handlers attached
574 * to the device have their start() method called so they have a change
575 * to synchronize device state with the rest of the system.
576 */
577 void input_release_device(struct input_handle *handle)
578 {
579 struct input_dev *dev = handle->dev;
580
581 mutex_lock(&dev->mutex);
582 __input_release_device(handle);
583 mutex_unlock(&dev->mutex);
584 }
585 EXPORT_SYMBOL(input_release_device);
586
587 /**
588 * input_open_device - open input device
589 * @handle: handle through which device is being accessed
590 *
591 * This function should be called by input handlers when they
592 * want to start receive events from given input device.
593 */
594 int input_open_device(struct input_handle *handle)
595 {
596 struct input_dev *dev = handle->dev;
597 int retval;
598
599 retval = mutex_lock_interruptible(&dev->mutex);
600 if (retval)
601 return retval;
602
603 if (dev->going_away) {
604 retval = -ENODEV;
605 goto out;
606 }
607
608 handle->open++;
609
610 if (!dev->users++ && dev->open)
611 retval = dev->open(dev);
612
613 if (retval) {
614 dev->users--;
615 if (!--handle->open) {
616 /*
617 * Make sure we are not delivering any more events
618 * through this handle
619 */
620 synchronize_rcu();
621 }
622 }
623
624 out:
625 mutex_unlock(&dev->mutex);
626 return retval;
627 }
628 EXPORT_SYMBOL(input_open_device);
629
630 int input_flush_device(struct input_handle *handle, struct file *file)
631 {
632 struct input_dev *dev = handle->dev;
633 int retval;
634
635 retval = mutex_lock_interruptible(&dev->mutex);
636 if (retval)
637 return retval;
638
639 if (dev->flush)
640 retval = dev->flush(dev, file);
641
642 mutex_unlock(&dev->mutex);
643 return retval;
644 }
645 EXPORT_SYMBOL(input_flush_device);
646
647 /**
648 * input_close_device - close input device
649 * @handle: handle through which device is being accessed
650 *
651 * This function should be called by input handlers when they
652 * want to stop receive events from given input device.
653 */
654 void input_close_device(struct input_handle *handle)
655 {
656 struct input_dev *dev = handle->dev;
657
658 mutex_lock(&dev->mutex);
659
660 __input_release_device(handle);
661
662 if (!--dev->users && dev->close)
663 dev->close(dev);
664
665 if (!--handle->open) {
666 /*
667 * synchronize_rcu() makes sure that input_pass_event()
668 * completed and that no more input events are delivered
669 * through this handle
670 */
671 synchronize_rcu();
672 }
673
674 mutex_unlock(&dev->mutex);
675 }
676 EXPORT_SYMBOL(input_close_device);
677
678 /*
679 * Simulate keyup events for all keys that are marked as pressed.
680 * The function must be called with dev->event_lock held.
681 */
682 static void input_dev_release_keys(struct input_dev *dev)
683 {
684 bool need_sync = false;
685 int code;
686
687 if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
688 for_each_set_bit(code, dev->key, KEY_CNT) {
689 input_pass_event(dev, EV_KEY, code, 0);
690 need_sync = true;
691 }
692
693 if (need_sync)
694 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
695
696 memset(dev->key, 0, sizeof(dev->key));
697 }
698 }
699
700 /*
701 * Prepare device for unregistering
702 */
703 static void input_disconnect_device(struct input_dev *dev)
704 {
705 struct input_handle *handle;
706
707 /*
708 * Mark device as going away. Note that we take dev->mutex here
709 * not to protect access to dev->going_away but rather to ensure
710 * that there are no threads in the middle of input_open_device()
711 */
712 mutex_lock(&dev->mutex);
713 dev->going_away = true;
714 mutex_unlock(&dev->mutex);
715
716 spin_lock_irq(&dev->event_lock);
717
718 /*
719 * Simulate keyup events for all pressed keys so that handlers
720 * are not left with "stuck" keys. The driver may continue
721 * generate events even after we done here but they will not
722 * reach any handlers.
723 */
724 input_dev_release_keys(dev);
725
726 list_for_each_entry(handle, &dev->h_list, d_node)
727 handle->open = 0;
728
729 spin_unlock_irq(&dev->event_lock);
730 }
731
732 /**
733 * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
734 * @ke: keymap entry containing scancode to be converted.
735 * @scancode: pointer to the location where converted scancode should
736 * be stored.
737 *
738 * This function is used to convert scancode stored in &struct keymap_entry
739 * into scalar form understood by legacy keymap handling methods. These
740 * methods expect scancodes to be represented as 'unsigned int'.
741 */
742 int input_scancode_to_scalar(const struct input_keymap_entry *ke,
743 unsigned int *scancode)
744 {
745 switch (ke->len) {
746 case 1:
747 *scancode = *((u8 *)ke->scancode);
748 break;
749
750 case 2:
751 *scancode = *((u16 *)ke->scancode);
752 break;
753
754 case 4:
755 *scancode = *((u32 *)ke->scancode);
756 break;
757
758 default:
759 return -EINVAL;
760 }
761
762 return 0;
763 }
764 EXPORT_SYMBOL(input_scancode_to_scalar);
765
766 /*
767 * Those routines handle the default case where no [gs]etkeycode() is
768 * defined. In this case, an array indexed by the scancode is used.
769 */
770
771 static unsigned int input_fetch_keycode(struct input_dev *dev,
772 unsigned int index)
773 {
774 switch (dev->keycodesize) {
775 case 1:
776 return ((u8 *)dev->keycode)[index];
777
778 case 2:
779 return ((u16 *)dev->keycode)[index];
780
781 default:
782 return ((u32 *)dev->keycode)[index];
783 }
784 }
785
786 static int input_default_getkeycode(struct input_dev *dev,
787 struct input_keymap_entry *ke)
788 {
789 unsigned int index;
790 int error;
791
792 if (!dev->keycodesize)
793 return -EINVAL;
794
795 if (ke->flags & INPUT_KEYMAP_BY_INDEX)
796 index = ke->index;
797 else {
798 error = input_scancode_to_scalar(ke, &index);
799 if (error)
800 return error;
801 }
802
803 if (index >= dev->keycodemax)
804 return -EINVAL;
805
806 ke->keycode = input_fetch_keycode(dev, index);
807 ke->index = index;
808 ke->len = sizeof(index);
809 memcpy(ke->scancode, &index, sizeof(index));
810
811 return 0;
812 }
813
814 static int input_default_setkeycode(struct input_dev *dev,
815 const struct input_keymap_entry *ke,
816 unsigned int *old_keycode)
817 {
818 unsigned int index;
819 int error;
820 int i;
821
822 if (!dev->keycodesize)
823 return -EINVAL;
824
825 if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
826 index = ke->index;
827 } else {
828 error = input_scancode_to_scalar(ke, &index);
829 if (error)
830 return error;
831 }
832
833 if (index >= dev->keycodemax)
834 return -EINVAL;
835
836 if (dev->keycodesize < sizeof(ke->keycode) &&
837 (ke->keycode >> (dev->keycodesize * 8)))
838 return -EINVAL;
839
840 switch (dev->keycodesize) {
841 case 1: {
842 u8 *k = (u8 *)dev->keycode;
843 *old_keycode = k[index];
844 k[index] = ke->keycode;
845 break;
846 }
847 case 2: {
848 u16 *k = (u16 *)dev->keycode;
849 *old_keycode = k[index];
850 k[index] = ke->keycode;
851 break;
852 }
853 default: {
854 u32 *k = (u32 *)dev->keycode;
855 *old_keycode = k[index];
856 k[index] = ke->keycode;
857 break;
858 }
859 }
860
861 if (*old_keycode <= KEY_MAX) {
862 __clear_bit(*old_keycode, dev->keybit);
863 for (i = 0; i < dev->keycodemax; i++) {
864 if (input_fetch_keycode(dev, i) == *old_keycode) {
865 __set_bit(*old_keycode, dev->keybit);
866 /* Setting the bit twice is useless, so break */
867 break;
868 }
869 }
870 }
871
872 __set_bit(ke->keycode, dev->keybit);
873 return 0;
874 }
875
876 /**
877 * input_get_keycode - retrieve keycode currently mapped to a given scancode
878 * @dev: input device which keymap is being queried
879 * @ke: keymap entry
880 *
881 * This function should be called by anyone interested in retrieving current
882 * keymap. Presently evdev handlers use it.
883 */
884 int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
885 {
886 unsigned long flags;
887 int retval;
888
889 spin_lock_irqsave(&dev->event_lock, flags);
890 retval = dev->getkeycode(dev, ke);
891 spin_unlock_irqrestore(&dev->event_lock, flags);
892
893 return retval;
894 }
895 EXPORT_SYMBOL(input_get_keycode);
896
897 /**
898 * input_set_keycode - attribute a keycode to a given scancode
899 * @dev: input device which keymap is being updated
900 * @ke: new keymap entry
901 *
902 * This function should be called by anyone needing to update current
903 * keymap. Presently keyboard and evdev handlers use it.
904 */
905 int input_set_keycode(struct input_dev *dev,
906 const struct input_keymap_entry *ke)
907 {
908 unsigned long flags;
909 unsigned int old_keycode;
910 int retval;
911
912 if (ke->keycode > KEY_MAX)
913 return -EINVAL;
914
915 spin_lock_irqsave(&dev->event_lock, flags);
916
917 retval = dev->setkeycode(dev, ke, &old_keycode);
918 if (retval)
919 goto out;
920
921 /* Make sure KEY_RESERVED did not get enabled. */
922 __clear_bit(KEY_RESERVED, dev->keybit);
923
924 /*
925 * Simulate keyup event if keycode is not present
926 * in the keymap anymore
927 */
928 if (old_keycode > KEY_MAX) {
929 dev_warn(dev->dev.parent ?: &dev->dev,
930 "%s: got too big old keycode %#x\n",
931 __func__, old_keycode);
932 } else if (test_bit(EV_KEY, dev->evbit) &&
933 !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
934 __test_and_clear_bit(old_keycode, dev->key)) {
935 struct input_value vals[] = {
936 { EV_KEY, old_keycode, 0 },
937 input_value_sync
938 };
939
940 input_pass_values(dev, vals, ARRAY_SIZE(vals));
941 }
942
943 out:
944 spin_unlock_irqrestore(&dev->event_lock, flags);
945
946 return retval;
947 }
948 EXPORT_SYMBOL(input_set_keycode);
949
950 bool input_match_device_id(const struct input_dev *dev,
951 const struct input_device_id *id)
952 {
953 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
954 if (id->bustype != dev->id.bustype)
955 return false;
956
957 if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
958 if (id->vendor != dev->id.vendor)
959 return false;
960
961 if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
962 if (id->product != dev->id.product)
963 return false;
964
965 if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
966 if (id->version != dev->id.version)
967 return false;
968
969 if (!bitmap_subset(id->evbit, dev->evbit, EV_MAX) ||
970 !bitmap_subset(id->keybit, dev->keybit, KEY_MAX) ||
971 !bitmap_subset(id->relbit, dev->relbit, REL_MAX) ||
972 !bitmap_subset(id->absbit, dev->absbit, ABS_MAX) ||
973 !bitmap_subset(id->mscbit, dev->mscbit, MSC_MAX) ||
974 !bitmap_subset(id->ledbit, dev->ledbit, LED_MAX) ||
975 !bitmap_subset(id->sndbit, dev->sndbit, SND_MAX) ||
976 !bitmap_subset(id->ffbit, dev->ffbit, FF_MAX) ||
977 !bitmap_subset(id->swbit, dev->swbit, SW_MAX) ||
978 !bitmap_subset(id->propbit, dev->propbit, INPUT_PROP_MAX)) {
979 return false;
980 }
981
982 return true;
983 }
984 EXPORT_SYMBOL(input_match_device_id);
985
986 static const struct input_device_id *input_match_device(struct input_handler *handler,
987 struct input_dev *dev)
988 {
989 const struct input_device_id *id;
990
991 for (id = handler->id_table; id->flags || id->driver_info; id++) {
992 if (input_match_device_id(dev, id) &&
993 (!handler->match || handler->match(handler, dev))) {
994 return id;
995 }
996 }
997
998 return NULL;
999 }
1000
1001 static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
1002 {
1003 const struct input_device_id *id;
1004 int error;
1005
1006 id = input_match_device(handler, dev);
1007 if (!id)
1008 return -ENODEV;
1009
1010 error = handler->connect(handler, dev, id);
1011 if (error && error != -ENODEV)
1012 pr_err("failed to attach handler %s to device %s, error: %d\n",
1013 handler->name, kobject_name(&dev->dev.kobj), error);
1014
1015 return error;
1016 }
1017
1018 #ifdef CONFIG_COMPAT
1019
1020 static int input_bits_to_string(char *buf, int buf_size,
1021 unsigned long bits, bool skip_empty)
1022 {
1023 int len = 0;
1024
1025 if (in_compat_syscall()) {
1026 u32 dword = bits >> 32;
1027 if (dword || !skip_empty)
1028 len += snprintf(buf, buf_size, "%x ", dword);
1029
1030 dword = bits & 0xffffffffUL;
1031 if (dword || !skip_empty || len)
1032 len += snprintf(buf + len, max(buf_size - len, 0),
1033 "%x", dword);
1034 } else {
1035 if (bits || !skip_empty)
1036 len += snprintf(buf, buf_size, "%lx", bits);
1037 }
1038
1039 return len;
1040 }
1041
1042 #else /* !CONFIG_COMPAT */
1043
1044 static int input_bits_to_string(char *buf, int buf_size,
1045 unsigned long bits, bool skip_empty)
1046 {
1047 return bits || !skip_empty ?
1048 snprintf(buf, buf_size, "%lx", bits) : 0;
1049 }
1050
1051 #endif
1052
1053 #ifdef CONFIG_PROC_FS
1054
1055 static struct proc_dir_entry *proc_bus_input_dir;
1056 static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
1057 static int input_devices_state;
1058
1059 static inline void input_wakeup_procfs_readers(void)
1060 {
1061 input_devices_state++;
1062 wake_up(&input_devices_poll_wait);
1063 }
1064
1065 static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
1066 {
1067 poll_wait(file, &input_devices_poll_wait, wait);
1068 if (file->f_version != input_devices_state) {
1069 file->f_version = input_devices_state;
1070 return POLLIN | POLLRDNORM;
1071 }
1072
1073 return 0;
1074 }
1075
1076 union input_seq_state {
1077 struct {
1078 unsigned short pos;
1079 bool mutex_acquired;
1080 };
1081 void *p;
1082 };
1083
1084 static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
1085 {
1086 union input_seq_state *state = (union input_seq_state *)&seq->private;
1087 int error;
1088
1089 /* We need to fit into seq->private pointer */
1090 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1091
1092 error = mutex_lock_interruptible(&input_mutex);
1093 if (error) {
1094 state->mutex_acquired = false;
1095 return ERR_PTR(error);
1096 }
1097
1098 state->mutex_acquired = true;
1099
1100 return seq_list_start(&input_dev_list, *pos);
1101 }
1102
1103 static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1104 {
1105 return seq_list_next(v, &input_dev_list, pos);
1106 }
1107
1108 static void input_seq_stop(struct seq_file *seq, void *v)
1109 {
1110 union input_seq_state *state = (union input_seq_state *)&seq->private;
1111
1112 if (state->mutex_acquired)
1113 mutex_unlock(&input_mutex);
1114 }
1115
1116 static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
1117 unsigned long *bitmap, int max)
1118 {
1119 int i;
1120 bool skip_empty = true;
1121 char buf[18];
1122
1123 seq_printf(seq, "B: %s=", name);
1124
1125 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1126 if (input_bits_to_string(buf, sizeof(buf),
1127 bitmap[i], skip_empty)) {
1128 skip_empty = false;
1129 seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
1130 }
1131 }
1132
1133 /*
1134 * If no output was produced print a single 0.
1135 */
1136 if (skip_empty)
1137 seq_putc(seq, '0');
1138
1139 seq_putc(seq, '\n');
1140 }
1141
1142 static int input_devices_seq_show(struct seq_file *seq, void *v)
1143 {
1144 struct input_dev *dev = container_of(v, struct input_dev, node);
1145 const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1146 struct input_handle *handle;
1147
1148 seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
1149 dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
1150
1151 seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
1152 seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
1153 seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
1154 seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1155 seq_puts(seq, "H: Handlers=");
1156
1157 list_for_each_entry(handle, &dev->h_list, d_node)
1158 seq_printf(seq, "%s ", handle->name);
1159 seq_putc(seq, '\n');
1160
1161 input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
1162
1163 input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
1164 if (test_bit(EV_KEY, dev->evbit))
1165 input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
1166 if (test_bit(EV_REL, dev->evbit))
1167 input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
1168 if (test_bit(EV_ABS, dev->evbit))
1169 input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
1170 if (test_bit(EV_MSC, dev->evbit))
1171 input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
1172 if (test_bit(EV_LED, dev->evbit))
1173 input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
1174 if (test_bit(EV_SND, dev->evbit))
1175 input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
1176 if (test_bit(EV_FF, dev->evbit))
1177 input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
1178 if (test_bit(EV_SW, dev->evbit))
1179 input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
1180
1181 seq_putc(seq, '\n');
1182
1183 kfree(path);
1184 return 0;
1185 }
1186
1187 static const struct seq_operations input_devices_seq_ops = {
1188 .start = input_devices_seq_start,
1189 .next = input_devices_seq_next,
1190 .stop = input_seq_stop,
1191 .show = input_devices_seq_show,
1192 };
1193
1194 static int input_proc_devices_open(struct inode *inode, struct file *file)
1195 {
1196 return seq_open(file, &input_devices_seq_ops);
1197 }
1198
1199 static const struct file_operations input_devices_fileops = {
1200 .owner = THIS_MODULE,
1201 .open = input_proc_devices_open,
1202 .poll = input_proc_devices_poll,
1203 .read = seq_read,
1204 .llseek = seq_lseek,
1205 .release = seq_release,
1206 };
1207
1208 static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
1209 {
1210 union input_seq_state *state = (union input_seq_state *)&seq->private;
1211 int error;
1212
1213 /* We need to fit into seq->private pointer */
1214 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1215
1216 error = mutex_lock_interruptible(&input_mutex);
1217 if (error) {
1218 state->mutex_acquired = false;
1219 return ERR_PTR(error);
1220 }
1221
1222 state->mutex_acquired = true;
1223 state->pos = *pos;
1224
1225 return seq_list_start(&input_handler_list, *pos);
1226 }
1227
1228 static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1229 {
1230 union input_seq_state *state = (union input_seq_state *)&seq->private;
1231
1232 state->pos = *pos + 1;
1233 return seq_list_next(v, &input_handler_list, pos);
1234 }
1235
1236 static int input_handlers_seq_show(struct seq_file *seq, void *v)
1237 {
1238 struct input_handler *handler = container_of(v, struct input_handler, node);
1239 union input_seq_state *state = (union input_seq_state *)&seq->private;
1240
1241 seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
1242 if (handler->filter)
1243 seq_puts(seq, " (filter)");
1244 if (handler->legacy_minors)
1245 seq_printf(seq, " Minor=%d", handler->minor);
1246 seq_putc(seq, '\n');
1247
1248 return 0;
1249 }
1250
1251 static const struct seq_operations input_handlers_seq_ops = {
1252 .start = input_handlers_seq_start,
1253 .next = input_handlers_seq_next,
1254 .stop = input_seq_stop,
1255 .show = input_handlers_seq_show,
1256 };
1257
1258 static int input_proc_handlers_open(struct inode *inode, struct file *file)
1259 {
1260 return seq_open(file, &input_handlers_seq_ops);
1261 }
1262
1263 static const struct file_operations input_handlers_fileops = {
1264 .owner = THIS_MODULE,
1265 .open = input_proc_handlers_open,
1266 .read = seq_read,
1267 .llseek = seq_lseek,
1268 .release = seq_release,
1269 };
1270
1271 static int __init input_proc_init(void)
1272 {
1273 struct proc_dir_entry *entry;
1274
1275 proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1276 if (!proc_bus_input_dir)
1277 return -ENOMEM;
1278
1279 entry = proc_create("devices", 0, proc_bus_input_dir,
1280 &input_devices_fileops);
1281 if (!entry)
1282 goto fail1;
1283
1284 entry = proc_create("handlers", 0, proc_bus_input_dir,
1285 &input_handlers_fileops);
1286 if (!entry)
1287 goto fail2;
1288
1289 return 0;
1290
1291 fail2: remove_proc_entry("devices", proc_bus_input_dir);
1292 fail1: remove_proc_entry("bus/input", NULL);
1293 return -ENOMEM;
1294 }
1295
1296 static void input_proc_exit(void)
1297 {
1298 remove_proc_entry("devices", proc_bus_input_dir);
1299 remove_proc_entry("handlers", proc_bus_input_dir);
1300 remove_proc_entry("bus/input", NULL);
1301 }
1302
1303 #else /* !CONFIG_PROC_FS */
1304 static inline void input_wakeup_procfs_readers(void) { }
1305 static inline int input_proc_init(void) { return 0; }
1306 static inline void input_proc_exit(void) { }
1307 #endif
1308
1309 #define INPUT_DEV_STRING_ATTR_SHOW(name) \
1310 static ssize_t input_dev_show_##name(struct device *dev, \
1311 struct device_attribute *attr, \
1312 char *buf) \
1313 { \
1314 struct input_dev *input_dev = to_input_dev(dev); \
1315 \
1316 return scnprintf(buf, PAGE_SIZE, "%s\n", \
1317 input_dev->name ? input_dev->name : ""); \
1318 } \
1319 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1320
1321 INPUT_DEV_STRING_ATTR_SHOW(name);
1322 INPUT_DEV_STRING_ATTR_SHOW(phys);
1323 INPUT_DEV_STRING_ATTR_SHOW(uniq);
1324
1325 static int input_print_modalias_bits(char *buf, int size,
1326 char name, unsigned long *bm,
1327 unsigned int min_bit, unsigned int max_bit)
1328 {
1329 int len = 0, i;
1330
1331 len += snprintf(buf, max(size, 0), "%c", name);
1332 for (i = min_bit; i < max_bit; i++)
1333 if (bm[BIT_WORD(i)] & BIT_MASK(i))
1334 len += snprintf(buf + len, max(size - len, 0), "%X,", i);
1335 return len;
1336 }
1337
1338 static int input_print_modalias(char *buf, int size, struct input_dev *id,
1339 int add_cr)
1340 {
1341 int len;
1342
1343 len = snprintf(buf, max(size, 0),
1344 "input:b%04Xv%04Xp%04Xe%04X-",
1345 id->id.bustype, id->id.vendor,
1346 id->id.product, id->id.version);
1347
1348 len += input_print_modalias_bits(buf + len, size - len,
1349 'e', id->evbit, 0, EV_MAX);
1350 len += input_print_modalias_bits(buf + len, size - len,
1351 'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1352 len += input_print_modalias_bits(buf + len, size - len,
1353 'r', id->relbit, 0, REL_MAX);
1354 len += input_print_modalias_bits(buf + len, size - len,
1355 'a', id->absbit, 0, ABS_MAX);
1356 len += input_print_modalias_bits(buf + len, size - len,
1357 'm', id->mscbit, 0, MSC_MAX);
1358 len += input_print_modalias_bits(buf + len, size - len,
1359 'l', id->ledbit, 0, LED_MAX);
1360 len += input_print_modalias_bits(buf + len, size - len,
1361 's', id->sndbit, 0, SND_MAX);
1362 len += input_print_modalias_bits(buf + len, size - len,
1363 'f', id->ffbit, 0, FF_MAX);
1364 len += input_print_modalias_bits(buf + len, size - len,
1365 'w', id->swbit, 0, SW_MAX);
1366
1367 if (add_cr)
1368 len += snprintf(buf + len, max(size - len, 0), "\n");
1369
1370 return len;
1371 }
1372
1373 static ssize_t input_dev_show_modalias(struct device *dev,
1374 struct device_attribute *attr,
1375 char *buf)
1376 {
1377 struct input_dev *id = to_input_dev(dev);
1378 ssize_t len;
1379
1380 len = input_print_modalias(buf, PAGE_SIZE, id, 1);
1381
1382 return min_t(int, len, PAGE_SIZE);
1383 }
1384 static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1385
1386 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1387 int max, int add_cr);
1388
1389 static ssize_t input_dev_show_properties(struct device *dev,
1390 struct device_attribute *attr,
1391 char *buf)
1392 {
1393 struct input_dev *input_dev = to_input_dev(dev);
1394 int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
1395 INPUT_PROP_MAX, true);
1396 return min_t(int, len, PAGE_SIZE);
1397 }
1398 static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
1399
1400 static struct attribute *input_dev_attrs[] = {
1401 &dev_attr_name.attr,
1402 &dev_attr_phys.attr,
1403 &dev_attr_uniq.attr,
1404 &dev_attr_modalias.attr,
1405 &dev_attr_properties.attr,
1406 NULL
1407 };
1408
1409 static const struct attribute_group input_dev_attr_group = {
1410 .attrs = input_dev_attrs,
1411 };
1412
1413 #define INPUT_DEV_ID_ATTR(name) \
1414 static ssize_t input_dev_show_id_##name(struct device *dev, \
1415 struct device_attribute *attr, \
1416 char *buf) \
1417 { \
1418 struct input_dev *input_dev = to_input_dev(dev); \
1419 return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name); \
1420 } \
1421 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1422
1423 INPUT_DEV_ID_ATTR(bustype);
1424 INPUT_DEV_ID_ATTR(vendor);
1425 INPUT_DEV_ID_ATTR(product);
1426 INPUT_DEV_ID_ATTR(version);
1427
1428 static struct attribute *input_dev_id_attrs[] = {
1429 &dev_attr_bustype.attr,
1430 &dev_attr_vendor.attr,
1431 &dev_attr_product.attr,
1432 &dev_attr_version.attr,
1433 NULL
1434 };
1435
1436 static const struct attribute_group input_dev_id_attr_group = {
1437 .name = "id",
1438 .attrs = input_dev_id_attrs,
1439 };
1440
1441 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1442 int max, int add_cr)
1443 {
1444 int i;
1445 int len = 0;
1446 bool skip_empty = true;
1447
1448 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1449 len += input_bits_to_string(buf + len, max(buf_size - len, 0),
1450 bitmap[i], skip_empty);
1451 if (len) {
1452 skip_empty = false;
1453 if (i > 0)
1454 len += snprintf(buf + len, max(buf_size - len, 0), " ");
1455 }
1456 }
1457
1458 /*
1459 * If no output was produced print a single 0.
1460 */
1461 if (len == 0)
1462 len = snprintf(buf, buf_size, "%d", 0);
1463
1464 if (add_cr)
1465 len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1466
1467 return len;
1468 }
1469
1470 #define INPUT_DEV_CAP_ATTR(ev, bm) \
1471 static ssize_t input_dev_show_cap_##bm(struct device *dev, \
1472 struct device_attribute *attr, \
1473 char *buf) \
1474 { \
1475 struct input_dev *input_dev = to_input_dev(dev); \
1476 int len = input_print_bitmap(buf, PAGE_SIZE, \
1477 input_dev->bm##bit, ev##_MAX, \
1478 true); \
1479 return min_t(int, len, PAGE_SIZE); \
1480 } \
1481 static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1482
1483 INPUT_DEV_CAP_ATTR(EV, ev);
1484 INPUT_DEV_CAP_ATTR(KEY, key);
1485 INPUT_DEV_CAP_ATTR(REL, rel);
1486 INPUT_DEV_CAP_ATTR(ABS, abs);
1487 INPUT_DEV_CAP_ATTR(MSC, msc);
1488 INPUT_DEV_CAP_ATTR(LED, led);
1489 INPUT_DEV_CAP_ATTR(SND, snd);
1490 INPUT_DEV_CAP_ATTR(FF, ff);
1491 INPUT_DEV_CAP_ATTR(SW, sw);
1492
1493 static struct attribute *input_dev_caps_attrs[] = {
1494 &dev_attr_ev.attr,
1495 &dev_attr_key.attr,
1496 &dev_attr_rel.attr,
1497 &dev_attr_abs.attr,
1498 &dev_attr_msc.attr,
1499 &dev_attr_led.attr,
1500 &dev_attr_snd.attr,
1501 &dev_attr_ff.attr,
1502 &dev_attr_sw.attr,
1503 NULL
1504 };
1505
1506 static const struct attribute_group input_dev_caps_attr_group = {
1507 .name = "capabilities",
1508 .attrs = input_dev_caps_attrs,
1509 };
1510
1511 static const struct attribute_group *input_dev_attr_groups[] = {
1512 &input_dev_attr_group,
1513 &input_dev_id_attr_group,
1514 &input_dev_caps_attr_group,
1515 NULL
1516 };
1517
1518 static void input_dev_release(struct device *device)
1519 {
1520 struct input_dev *dev = to_input_dev(device);
1521
1522 input_ff_destroy(dev);
1523 input_mt_destroy_slots(dev);
1524 kfree(dev->absinfo);
1525 kfree(dev->vals);
1526 kfree(dev);
1527
1528 module_put(THIS_MODULE);
1529 }
1530
1531 /*
1532 * Input uevent interface - loading event handlers based on
1533 * device bitfields.
1534 */
1535 static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1536 const char *name, unsigned long *bitmap, int max)
1537 {
1538 int len;
1539
1540 if (add_uevent_var(env, "%s", name))
1541 return -ENOMEM;
1542
1543 len = input_print_bitmap(&env->buf[env->buflen - 1],
1544 sizeof(env->buf) - env->buflen,
1545 bitmap, max, false);
1546 if (len >= (sizeof(env->buf) - env->buflen))
1547 return -ENOMEM;
1548
1549 env->buflen += len;
1550 return 0;
1551 }
1552
1553 static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1554 struct input_dev *dev)
1555 {
1556 int len;
1557
1558 if (add_uevent_var(env, "MODALIAS="))
1559 return -ENOMEM;
1560
1561 len = input_print_modalias(&env->buf[env->buflen - 1],
1562 sizeof(env->buf) - env->buflen,
1563 dev, 0);
1564 if (len >= (sizeof(env->buf) - env->buflen))
1565 return -ENOMEM;
1566
1567 env->buflen += len;
1568 return 0;
1569 }
1570
1571 #define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \
1572 do { \
1573 int err = add_uevent_var(env, fmt, val); \
1574 if (err) \
1575 return err; \
1576 } while (0)
1577
1578 #define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max) \
1579 do { \
1580 int err = input_add_uevent_bm_var(env, name, bm, max); \
1581 if (err) \
1582 return err; \
1583 } while (0)
1584
1585 #define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \
1586 do { \
1587 int err = input_add_uevent_modalias_var(env, dev); \
1588 if (err) \
1589 return err; \
1590 } while (0)
1591
1592 static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
1593 {
1594 struct input_dev *dev = to_input_dev(device);
1595
1596 INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1597 dev->id.bustype, dev->id.vendor,
1598 dev->id.product, dev->id.version);
1599 if (dev->name)
1600 INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1601 if (dev->phys)
1602 INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1603 if (dev->uniq)
1604 INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1605
1606 INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
1607
1608 INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1609 if (test_bit(EV_KEY, dev->evbit))
1610 INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1611 if (test_bit(EV_REL, dev->evbit))
1612 INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1613 if (test_bit(EV_ABS, dev->evbit))
1614 INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1615 if (test_bit(EV_MSC, dev->evbit))
1616 INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1617 if (test_bit(EV_LED, dev->evbit))
1618 INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1619 if (test_bit(EV_SND, dev->evbit))
1620 INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1621 if (test_bit(EV_FF, dev->evbit))
1622 INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1623 if (test_bit(EV_SW, dev->evbit))
1624 INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1625
1626 INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1627
1628 return 0;
1629 }
1630
1631 #define INPUT_DO_TOGGLE(dev, type, bits, on) \
1632 do { \
1633 int i; \
1634 bool active; \
1635 \
1636 if (!test_bit(EV_##type, dev->evbit)) \
1637 break; \
1638 \
1639 for_each_set_bit(i, dev->bits##bit, type##_CNT) { \
1640 active = test_bit(i, dev->bits); \
1641 if (!active && !on) \
1642 continue; \
1643 \
1644 dev->event(dev, EV_##type, i, on ? active : 0); \
1645 } \
1646 } while (0)
1647
1648 static void input_dev_toggle(struct input_dev *dev, bool activate)
1649 {
1650 if (!dev->event)
1651 return;
1652
1653 INPUT_DO_TOGGLE(dev, LED, led, activate);
1654 INPUT_DO_TOGGLE(dev, SND, snd, activate);
1655
1656 if (activate && test_bit(EV_REP, dev->evbit)) {
1657 dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1658 dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1659 }
1660 }
1661
1662 /**
1663 * input_reset_device() - reset/restore the state of input device
1664 * @dev: input device whose state needs to be reset
1665 *
1666 * This function tries to reset the state of an opened input device and
1667 * bring internal state and state if the hardware in sync with each other.
1668 * We mark all keys as released, restore LED state, repeat rate, etc.
1669 */
1670 void input_reset_device(struct input_dev *dev)
1671 {
1672 unsigned long flags;
1673
1674 mutex_lock(&dev->mutex);
1675 spin_lock_irqsave(&dev->event_lock, flags);
1676
1677 input_dev_toggle(dev, true);
1678 input_dev_release_keys(dev);
1679
1680 spin_unlock_irqrestore(&dev->event_lock, flags);
1681 mutex_unlock(&dev->mutex);
1682 }
1683 EXPORT_SYMBOL(input_reset_device);
1684
1685 #ifdef CONFIG_PM_SLEEP
1686 static int input_dev_suspend(struct device *dev)
1687 {
1688 struct input_dev *input_dev = to_input_dev(dev);
1689
1690 spin_lock_irq(&input_dev->event_lock);
1691
1692 /*
1693 * Keys that are pressed now are unlikely to be
1694 * still pressed when we resume.
1695 */
1696 input_dev_release_keys(input_dev);
1697
1698 /* Turn off LEDs and sounds, if any are active. */
1699 input_dev_toggle(input_dev, false);
1700
1701 spin_unlock_irq(&input_dev->event_lock);
1702
1703 return 0;
1704 }
1705
1706 static int input_dev_resume(struct device *dev)
1707 {
1708 struct input_dev *input_dev = to_input_dev(dev);
1709
1710 spin_lock_irq(&input_dev->event_lock);
1711
1712 /* Restore state of LEDs and sounds, if any were active. */
1713 input_dev_toggle(input_dev, true);
1714
1715 spin_unlock_irq(&input_dev->event_lock);
1716
1717 return 0;
1718 }
1719
1720 static int input_dev_freeze(struct device *dev)
1721 {
1722 struct input_dev *input_dev = to_input_dev(dev);
1723
1724 spin_lock_irq(&input_dev->event_lock);
1725
1726 /*
1727 * Keys that are pressed now are unlikely to be
1728 * still pressed when we resume.
1729 */
1730 input_dev_release_keys(input_dev);
1731
1732 spin_unlock_irq(&input_dev->event_lock);
1733
1734 return 0;
1735 }
1736
1737 static int input_dev_poweroff(struct device *dev)
1738 {
1739 struct input_dev *input_dev = to_input_dev(dev);
1740
1741 spin_lock_irq(&input_dev->event_lock);
1742
1743 /* Turn off LEDs and sounds, if any are active. */
1744 input_dev_toggle(input_dev, false);
1745
1746 spin_unlock_irq(&input_dev->event_lock);
1747
1748 return 0;
1749 }
1750
1751 static const struct dev_pm_ops input_dev_pm_ops = {
1752 .suspend = input_dev_suspend,
1753 .resume = input_dev_resume,
1754 .freeze = input_dev_freeze,
1755 .poweroff = input_dev_poweroff,
1756 .restore = input_dev_resume,
1757 };
1758 #endif /* CONFIG_PM */
1759
1760 static const struct device_type input_dev_type = {
1761 .groups = input_dev_attr_groups,
1762 .release = input_dev_release,
1763 .uevent = input_dev_uevent,
1764 #ifdef CONFIG_PM_SLEEP
1765 .pm = &input_dev_pm_ops,
1766 #endif
1767 };
1768
1769 static char *input_devnode(struct device *dev, umode_t *mode)
1770 {
1771 return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
1772 }
1773
1774 struct class input_class = {
1775 .name = "input",
1776 .devnode = input_devnode,
1777 };
1778 EXPORT_SYMBOL_GPL(input_class);
1779
1780 /**
1781 * input_allocate_device - allocate memory for new input device
1782 *
1783 * Returns prepared struct input_dev or %NULL.
1784 *
1785 * NOTE: Use input_free_device() to free devices that have not been
1786 * registered; input_unregister_device() should be used for already
1787 * registered devices.
1788 */
1789 struct input_dev *input_allocate_device(void)
1790 {
1791 static atomic_t input_no = ATOMIC_INIT(-1);
1792 struct input_dev *dev;
1793
1794 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1795 if (dev) {
1796 dev->dev.type = &input_dev_type;
1797 dev->dev.class = &input_class;
1798 device_initialize(&dev->dev);
1799 mutex_init(&dev->mutex);
1800 spin_lock_init(&dev->event_lock);
1801 init_timer(&dev->timer);
1802 INIT_LIST_HEAD(&dev->h_list);
1803 INIT_LIST_HEAD(&dev->node);
1804
1805 dev_set_name(&dev->dev, "input%lu",
1806 (unsigned long)atomic_inc_return(&input_no));
1807
1808 __module_get(THIS_MODULE);
1809 }
1810
1811 return dev;
1812 }
1813 EXPORT_SYMBOL(input_allocate_device);
1814
1815 struct input_devres {
1816 struct input_dev *input;
1817 };
1818
1819 static int devm_input_device_match(struct device *dev, void *res, void *data)
1820 {
1821 struct input_devres *devres = res;
1822
1823 return devres->input == data;
1824 }
1825
1826 static void devm_input_device_release(struct device *dev, void *res)
1827 {
1828 struct input_devres *devres = res;
1829 struct input_dev *input = devres->input;
1830
1831 dev_dbg(dev, "%s: dropping reference to %s\n",
1832 __func__, dev_name(&input->dev));
1833 input_put_device(input);
1834 }
1835
1836 /**
1837 * devm_input_allocate_device - allocate managed input device
1838 * @dev: device owning the input device being created
1839 *
1840 * Returns prepared struct input_dev or %NULL.
1841 *
1842 * Managed input devices do not need to be explicitly unregistered or
1843 * freed as it will be done automatically when owner device unbinds from
1844 * its driver (or binding fails). Once managed input device is allocated,
1845 * it is ready to be set up and registered in the same fashion as regular
1846 * input device. There are no special devm_input_device_[un]register()
1847 * variants, regular ones work with both managed and unmanaged devices,
1848 * should you need them. In most cases however, managed input device need
1849 * not be explicitly unregistered or freed.
1850 *
1851 * NOTE: the owner device is set up as parent of input device and users
1852 * should not override it.
1853 */
1854 struct input_dev *devm_input_allocate_device(struct device *dev)
1855 {
1856 struct input_dev *input;
1857 struct input_devres *devres;
1858
1859 devres = devres_alloc(devm_input_device_release,
1860 sizeof(*devres), GFP_KERNEL);
1861 if (!devres)
1862 return NULL;
1863
1864 input = input_allocate_device();
1865 if (!input) {
1866 devres_free(devres);
1867 return NULL;
1868 }
1869
1870 input->dev.parent = dev;
1871 input->devres_managed = true;
1872
1873 devres->input = input;
1874 devres_add(dev, devres);
1875
1876 return input;
1877 }
1878 EXPORT_SYMBOL(devm_input_allocate_device);
1879
1880 /**
1881 * input_free_device - free memory occupied by input_dev structure
1882 * @dev: input device to free
1883 *
1884 * This function should only be used if input_register_device()
1885 * was not called yet or if it failed. Once device was registered
1886 * use input_unregister_device() and memory will be freed once last
1887 * reference to the device is dropped.
1888 *
1889 * Device should be allocated by input_allocate_device().
1890 *
1891 * NOTE: If there are references to the input device then memory
1892 * will not be freed until last reference is dropped.
1893 */
1894 void input_free_device(struct input_dev *dev)
1895 {
1896 if (dev) {
1897 if (dev->devres_managed)
1898 WARN_ON(devres_destroy(dev->dev.parent,
1899 devm_input_device_release,
1900 devm_input_device_match,
1901 dev));
1902 input_put_device(dev);
1903 }
1904 }
1905 EXPORT_SYMBOL(input_free_device);
1906
1907 /**
1908 * input_set_capability - mark device as capable of a certain event
1909 * @dev: device that is capable of emitting or accepting event
1910 * @type: type of the event (EV_KEY, EV_REL, etc...)
1911 * @code: event code
1912 *
1913 * In addition to setting up corresponding bit in appropriate capability
1914 * bitmap the function also adjusts dev->evbit.
1915 */
1916 void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
1917 {
1918 switch (type) {
1919 case EV_KEY:
1920 __set_bit(code, dev->keybit);
1921 break;
1922
1923 case EV_REL:
1924 __set_bit(code, dev->relbit);
1925 break;
1926
1927 case EV_ABS:
1928 input_alloc_absinfo(dev);
1929 if (!dev->absinfo)
1930 return;
1931
1932 __set_bit(code, dev->absbit);
1933 break;
1934
1935 case EV_MSC:
1936 __set_bit(code, dev->mscbit);
1937 break;
1938
1939 case EV_SW:
1940 __set_bit(code, dev->swbit);
1941 break;
1942
1943 case EV_LED:
1944 __set_bit(code, dev->ledbit);
1945 break;
1946
1947 case EV_SND:
1948 __set_bit(code, dev->sndbit);
1949 break;
1950
1951 case EV_FF:
1952 __set_bit(code, dev->ffbit);
1953 break;
1954
1955 case EV_PWR:
1956 /* do nothing */
1957 break;
1958
1959 default:
1960 pr_err("input_set_capability: unknown type %u (code %u)\n",
1961 type, code);
1962 dump_stack();
1963 return;
1964 }
1965
1966 __set_bit(type, dev->evbit);
1967 }
1968 EXPORT_SYMBOL(input_set_capability);
1969
1970 static unsigned int input_estimate_events_per_packet(struct input_dev *dev)
1971 {
1972 int mt_slots;
1973 int i;
1974 unsigned int events;
1975
1976 if (dev->mt) {
1977 mt_slots = dev->mt->num_slots;
1978 } else if (test_bit(ABS_MT_TRACKING_ID, dev->absbit)) {
1979 mt_slots = dev->absinfo[ABS_MT_TRACKING_ID].maximum -
1980 dev->absinfo[ABS_MT_TRACKING_ID].minimum + 1,
1981 mt_slots = clamp(mt_slots, 2, 32);
1982 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
1983 mt_slots = 2;
1984 } else {
1985 mt_slots = 0;
1986 }
1987
1988 events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */
1989
1990 if (test_bit(EV_ABS, dev->evbit))
1991 for_each_set_bit(i, dev->absbit, ABS_CNT)
1992 events += input_is_mt_axis(i) ? mt_slots : 1;
1993
1994 if (test_bit(EV_REL, dev->evbit))
1995 events += bitmap_weight(dev->relbit, REL_CNT);
1996
1997 /* Make room for KEY and MSC events */
1998 events += 7;
1999
2000 return events;
2001 }
2002
2003 #define INPUT_CLEANSE_BITMASK(dev, type, bits) \
2004 do { \
2005 if (!test_bit(EV_##type, dev->evbit)) \
2006 memset(dev->bits##bit, 0, \
2007 sizeof(dev->bits##bit)); \
2008 } while (0)
2009
2010 static void input_cleanse_bitmasks(struct input_dev *dev)
2011 {
2012 INPUT_CLEANSE_BITMASK(dev, KEY, key);
2013 INPUT_CLEANSE_BITMASK(dev, REL, rel);
2014 INPUT_CLEANSE_BITMASK(dev, ABS, abs);
2015 INPUT_CLEANSE_BITMASK(dev, MSC, msc);
2016 INPUT_CLEANSE_BITMASK(dev, LED, led);
2017 INPUT_CLEANSE_BITMASK(dev, SND, snd);
2018 INPUT_CLEANSE_BITMASK(dev, FF, ff);
2019 INPUT_CLEANSE_BITMASK(dev, SW, sw);
2020 }
2021
2022 static void __input_unregister_device(struct input_dev *dev)
2023 {
2024 struct input_handle *handle, *next;
2025
2026 input_disconnect_device(dev);
2027
2028 mutex_lock(&input_mutex);
2029
2030 list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
2031 handle->handler->disconnect(handle);
2032 WARN_ON(!list_empty(&dev->h_list));
2033
2034 del_timer_sync(&dev->timer);
2035 list_del_init(&dev->node);
2036
2037 input_wakeup_procfs_readers();
2038
2039 mutex_unlock(&input_mutex);
2040
2041 device_del(&dev->dev);
2042 }
2043
2044 static void devm_input_device_unregister(struct device *dev, void *res)
2045 {
2046 struct input_devres *devres = res;
2047 struct input_dev *input = devres->input;
2048
2049 dev_dbg(dev, "%s: unregistering device %s\n",
2050 __func__, dev_name(&input->dev));
2051 __input_unregister_device(input);
2052 }
2053
2054 /**
2055 * input_enable_softrepeat - enable software autorepeat
2056 * @dev: input device
2057 * @delay: repeat delay
2058 * @period: repeat period
2059 *
2060 * Enable software autorepeat on the input device.
2061 */
2062 void input_enable_softrepeat(struct input_dev *dev, int delay, int period)
2063 {
2064 dev->timer.data = (unsigned long) dev;
2065 dev->timer.function = input_repeat_key;
2066 dev->rep[REP_DELAY] = delay;
2067 dev->rep[REP_PERIOD] = period;
2068 }
2069 EXPORT_SYMBOL(input_enable_softrepeat);
2070
2071 /**
2072 * input_register_device - register device with input core
2073 * @dev: device to be registered
2074 *
2075 * This function registers device with input core. The device must be
2076 * allocated with input_allocate_device() and all it's capabilities
2077 * set up before registering.
2078 * If function fails the device must be freed with input_free_device().
2079 * Once device has been successfully registered it can be unregistered
2080 * with input_unregister_device(); input_free_device() should not be
2081 * called in this case.
2082 *
2083 * Note that this function is also used to register managed input devices
2084 * (ones allocated with devm_input_allocate_device()). Such managed input
2085 * devices need not be explicitly unregistered or freed, their tear down
2086 * is controlled by the devres infrastructure. It is also worth noting
2087 * that tear down of managed input devices is internally a 2-step process:
2088 * registered managed input device is first unregistered, but stays in
2089 * memory and can still handle input_event() calls (although events will
2090 * not be delivered anywhere). The freeing of managed input device will
2091 * happen later, when devres stack is unwound to the point where device
2092 * allocation was made.
2093 */
2094 int input_register_device(struct input_dev *dev)
2095 {
2096 struct input_devres *devres = NULL;
2097 struct input_handler *handler;
2098 unsigned int packet_size;
2099 const char *path;
2100 int error;
2101
2102 if (test_bit(EV_ABS, dev->evbit) && !dev->absinfo) {
2103 dev_err(&dev->dev,
2104 "Absolute device without dev->absinfo, refusing to register\n");
2105 return -EINVAL;
2106 }
2107
2108 if (dev->devres_managed) {
2109 devres = devres_alloc(devm_input_device_unregister,
2110 sizeof(*devres), GFP_KERNEL);
2111 if (!devres)
2112 return -ENOMEM;
2113
2114 devres->input = dev;
2115 }
2116
2117 /* Every input device generates EV_SYN/SYN_REPORT events. */
2118 __set_bit(EV_SYN, dev->evbit);
2119
2120 /* KEY_RESERVED is not supposed to be transmitted to userspace. */
2121 __clear_bit(KEY_RESERVED, dev->keybit);
2122
2123 /* Make sure that bitmasks not mentioned in dev->evbit are clean. */
2124 input_cleanse_bitmasks(dev);
2125
2126 packet_size = input_estimate_events_per_packet(dev);
2127 if (dev->hint_events_per_packet < packet_size)
2128 dev->hint_events_per_packet = packet_size;
2129
2130 dev->max_vals = dev->hint_events_per_packet + 2;
2131 dev->vals = kcalloc(dev->max_vals, sizeof(*dev->vals), GFP_KERNEL);
2132 if (!dev->vals) {
2133 error = -ENOMEM;
2134 goto err_devres_free;
2135 }
2136
2137 /*
2138 * If delay and period are pre-set by the driver, then autorepeating
2139 * is handled by the driver itself and we don't do it in input.c.
2140 */
2141 if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD])
2142 input_enable_softrepeat(dev, 250, 33);
2143
2144 if (!dev->getkeycode)
2145 dev->getkeycode = input_default_getkeycode;
2146
2147 if (!dev->setkeycode)
2148 dev->setkeycode = input_default_setkeycode;
2149
2150 error = device_add(&dev->dev);
2151 if (error)
2152 goto err_free_vals;
2153
2154 path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
2155 pr_info("%s as %s\n",
2156 dev->name ? dev->name : "Unspecified device",
2157 path ? path : "N/A");
2158 kfree(path);
2159
2160 error = mutex_lock_interruptible(&input_mutex);
2161 if (error)
2162 goto err_device_del;
2163
2164 list_add_tail(&dev->node, &input_dev_list);
2165
2166 list_for_each_entry(handler, &input_handler_list, node)
2167 input_attach_handler(dev, handler);
2168
2169 input_wakeup_procfs_readers();
2170
2171 mutex_unlock(&input_mutex);
2172
2173 if (dev->devres_managed) {
2174 dev_dbg(dev->dev.parent, "%s: registering %s with devres.\n",
2175 __func__, dev_name(&dev->dev));
2176 devres_add(dev->dev.parent, devres);
2177 }
2178 return 0;
2179
2180 err_device_del:
2181 device_del(&dev->dev);
2182 err_free_vals:
2183 kfree(dev->vals);
2184 dev->vals = NULL;
2185 err_devres_free:
2186 devres_free(devres);
2187 return error;
2188 }
2189 EXPORT_SYMBOL(input_register_device);
2190
2191 /**
2192 * input_unregister_device - unregister previously registered device
2193 * @dev: device to be unregistered
2194 *
2195 * This function unregisters an input device. Once device is unregistered
2196 * the caller should not try to access it as it may get freed at any moment.
2197 */
2198 void input_unregister_device(struct input_dev *dev)
2199 {
2200 if (dev->devres_managed) {
2201 WARN_ON(devres_destroy(dev->dev.parent,
2202 devm_input_device_unregister,
2203 devm_input_device_match,
2204 dev));
2205 __input_unregister_device(dev);
2206 /*
2207 * We do not do input_put_device() here because it will be done
2208 * when 2nd devres fires up.
2209 */
2210 } else {
2211 __input_unregister_device(dev);
2212 input_put_device(dev);
2213 }
2214 }
2215 EXPORT_SYMBOL(input_unregister_device);
2216
2217 /**
2218 * input_register_handler - register a new input handler
2219 * @handler: handler to be registered
2220 *
2221 * This function registers a new input handler (interface) for input
2222 * devices in the system and attaches it to all input devices that
2223 * are compatible with the handler.
2224 */
2225 int input_register_handler(struct input_handler *handler)
2226 {
2227 struct input_dev *dev;
2228 int error;
2229
2230 error = mutex_lock_interruptible(&input_mutex);
2231 if (error)
2232 return error;
2233
2234 INIT_LIST_HEAD(&handler->h_list);
2235
2236 list_add_tail(&handler->node, &input_handler_list);
2237
2238 list_for_each_entry(dev, &input_dev_list, node)
2239 input_attach_handler(dev, handler);
2240
2241 input_wakeup_procfs_readers();
2242
2243 mutex_unlock(&input_mutex);
2244 return 0;
2245 }
2246 EXPORT_SYMBOL(input_register_handler);
2247
2248 /**
2249 * input_unregister_handler - unregisters an input handler
2250 * @handler: handler to be unregistered
2251 *
2252 * This function disconnects a handler from its input devices and
2253 * removes it from lists of known handlers.
2254 */
2255 void input_unregister_handler(struct input_handler *handler)
2256 {
2257 struct input_handle *handle, *next;
2258
2259 mutex_lock(&input_mutex);
2260
2261 list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
2262 handler->disconnect(handle);
2263 WARN_ON(!list_empty(&handler->h_list));
2264
2265 list_del_init(&handler->node);
2266
2267 input_wakeup_procfs_readers();
2268
2269 mutex_unlock(&input_mutex);
2270 }
2271 EXPORT_SYMBOL(input_unregister_handler);
2272
2273 /**
2274 * input_handler_for_each_handle - handle iterator
2275 * @handler: input handler to iterate
2276 * @data: data for the callback
2277 * @fn: function to be called for each handle
2278 *
2279 * Iterate over @bus's list of devices, and call @fn for each, passing
2280 * it @data and stop when @fn returns a non-zero value. The function is
2281 * using RCU to traverse the list and therefore may be using in atomic
2282 * contexts. The @fn callback is invoked from RCU critical section and
2283 * thus must not sleep.
2284 */
2285 int input_handler_for_each_handle(struct input_handler *handler, void *data,
2286 int (*fn)(struct input_handle *, void *))
2287 {
2288 struct input_handle *handle;
2289 int retval = 0;
2290
2291 rcu_read_lock();
2292
2293 list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
2294 retval = fn(handle, data);
2295 if (retval)
2296 break;
2297 }
2298
2299 rcu_read_unlock();
2300
2301 return retval;
2302 }
2303 EXPORT_SYMBOL(input_handler_for_each_handle);
2304
2305 /**
2306 * input_register_handle - register a new input handle
2307 * @handle: handle to register
2308 *
2309 * This function puts a new input handle onto device's
2310 * and handler's lists so that events can flow through
2311 * it once it is opened using input_open_device().
2312 *
2313 * This function is supposed to be called from handler's
2314 * connect() method.
2315 */
2316 int input_register_handle(struct input_handle *handle)
2317 {
2318 struct input_handler *handler = handle->handler;
2319 struct input_dev *dev = handle->dev;
2320 int error;
2321
2322 /*
2323 * We take dev->mutex here to prevent race with
2324 * input_release_device().
2325 */
2326 error = mutex_lock_interruptible(&dev->mutex);
2327 if (error)
2328 return error;
2329
2330 /*
2331 * Filters go to the head of the list, normal handlers
2332 * to the tail.
2333 */
2334 if (handler->filter)
2335 list_add_rcu(&handle->d_node, &dev->h_list);
2336 else
2337 list_add_tail_rcu(&handle->d_node, &dev->h_list);
2338
2339 mutex_unlock(&dev->mutex);
2340
2341 /*
2342 * Since we are supposed to be called from ->connect()
2343 * which is mutually exclusive with ->disconnect()
2344 * we can't be racing with input_unregister_handle()
2345 * and so separate lock is not needed here.
2346 */
2347 list_add_tail_rcu(&handle->h_node, &handler->h_list);
2348
2349 if (handler->start)
2350 handler->start(handle);
2351
2352 return 0;
2353 }
2354 EXPORT_SYMBOL(input_register_handle);
2355
2356 /**
2357 * input_unregister_handle - unregister an input handle
2358 * @handle: handle to unregister
2359 *
2360 * This function removes input handle from device's
2361 * and handler's lists.
2362 *
2363 * This function is supposed to be called from handler's
2364 * disconnect() method.
2365 */
2366 void input_unregister_handle(struct input_handle *handle)
2367 {
2368 struct input_dev *dev = handle->dev;
2369
2370 list_del_rcu(&handle->h_node);
2371
2372 /*
2373 * Take dev->mutex to prevent race with input_release_device().
2374 */
2375 mutex_lock(&dev->mutex);
2376 list_del_rcu(&handle->d_node);
2377 mutex_unlock(&dev->mutex);
2378
2379 synchronize_rcu();
2380 }
2381 EXPORT_SYMBOL(input_unregister_handle);
2382
2383 /**
2384 * input_get_new_minor - allocates a new input minor number
2385 * @legacy_base: beginning or the legacy range to be searched
2386 * @legacy_num: size of legacy range
2387 * @allow_dynamic: whether we can also take ID from the dynamic range
2388 *
2389 * This function allocates a new device minor for from input major namespace.
2390 * Caller can request legacy minor by specifying @legacy_base and @legacy_num
2391 * parameters and whether ID can be allocated from dynamic range if there are
2392 * no free IDs in legacy range.
2393 */
2394 int input_get_new_minor(int legacy_base, unsigned int legacy_num,
2395 bool allow_dynamic)
2396 {
2397 /*
2398 * This function should be called from input handler's ->connect()
2399 * methods, which are serialized with input_mutex, so no additional
2400 * locking is needed here.
2401 */
2402 if (legacy_base >= 0) {
2403 int minor = ida_simple_get(&input_ida,
2404 legacy_base,
2405 legacy_base + legacy_num,
2406 GFP_KERNEL);
2407 if (minor >= 0 || !allow_dynamic)
2408 return minor;
2409 }
2410
2411 return ida_simple_get(&input_ida,
2412 INPUT_FIRST_DYNAMIC_DEV, INPUT_MAX_CHAR_DEVICES,
2413 GFP_KERNEL);
2414 }
2415 EXPORT_SYMBOL(input_get_new_minor);
2416
2417 /**
2418 * input_free_minor - release previously allocated minor
2419 * @minor: minor to be released
2420 *
2421 * This function releases previously allocated input minor so that it can be
2422 * reused later.
2423 */
2424 void input_free_minor(unsigned int minor)
2425 {
2426 ida_simple_remove(&input_ida, minor);
2427 }
2428 EXPORT_SYMBOL(input_free_minor);
2429
2430 static int __init input_init(void)
2431 {
2432 int err;
2433
2434 err = class_register(&input_class);
2435 if (err) {
2436 pr_err("unable to register input_dev class\n");
2437 return err;
2438 }
2439
2440 err = input_proc_init();
2441 if (err)
2442 goto fail1;
2443
2444 err = register_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2445 INPUT_MAX_CHAR_DEVICES, "input");
2446 if (err) {
2447 pr_err("unable to register char major %d", INPUT_MAJOR);
2448 goto fail2;
2449 }
2450
2451 return 0;
2452
2453 fail2: input_proc_exit();
2454 fail1: class_unregister(&input_class);
2455 return err;
2456 }
2457
2458 static void __exit input_exit(void)
2459 {
2460 input_proc_exit();
2461 unregister_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2462 INPUT_MAX_CHAR_DEVICES);
2463 class_unregister(&input_class);
2464 }
2465
2466 subsys_initcall(input_init);
2467 module_exit(input_exit);
Motorola kernel-slsi