Loading...
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/input/mt.h>
18#include <linux/module.h>
19#include <linux/slab.h>
20#include <linux/random.h>
21#include <linux/major.h>
22#include <linux/proc_fs.h>
23#include <linux/sched.h>
24#include <linux/seq_file.h>
25#include <linux/poll.h>
26#include <linux/device.h>
27#include <linux/mutex.h>
28#include <linux/rcupdate.h>
29#include "input-compat.h"
30
31MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
32MODULE_DESCRIPTION("Input core");
33MODULE_LICENSE("GPL");
34
35#define INPUT_DEVICES 256
36
37static LIST_HEAD(input_dev_list);
38static LIST_HEAD(input_handler_list);
39
40/*
41 * input_mutex protects access to both input_dev_list and input_handler_list.
42 * This also causes input_[un]register_device and input_[un]register_handler
43 * be mutually exclusive which simplifies locking in drivers implementing
44 * input handlers.
45 */
46static DEFINE_MUTEX(input_mutex);
47
48static struct input_handler *input_table[8];
49
50static inline int is_event_supported(unsigned int code,
51 unsigned long *bm, unsigned int max)
52{
53 return code <= max && test_bit(code, bm);
54}
55
56static int input_defuzz_abs_event(int value, int old_val, int fuzz)
57{
58 if (fuzz) {
59 if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
60 return old_val;
61
62 if (value > old_val - fuzz && value < old_val + fuzz)
63 return (old_val * 3 + value) / 4;
64
65 if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
66 return (old_val + value) / 2;
67 }
68
69 return value;
70}
71
72/*
73 * Pass event first through all filters and then, if event has not been
74 * filtered out, through all open handles. This function is called with
75 * dev->event_lock held and interrupts disabled.
76 */
77static void input_pass_event(struct input_dev *dev,
78 unsigned int type, unsigned int code, int value)
79{
80 struct input_handler *handler;
81 struct input_handle *handle;
82
83 rcu_read_lock();
84
85 handle = rcu_dereference(dev->grab);
86 if (handle)
87 handle->handler->event(handle, type, code, value);
88 else {
89 bool filtered = false;
90
91 list_for_each_entry_rcu(handle, &dev->h_list, d_node) {
92 if (!handle->open)
93 continue;
94
95 handler = handle->handler;
96 if (!handler->filter) {
97 if (filtered)
98 break;
99
100 handler->event(handle, type, code, value);
101
102 } else if (handler->filter(handle, type, code, value))
103 filtered = true;
104 }
105 }
106
107 rcu_read_unlock();
108}
109
110/*
111 * Generate software autorepeat event. Note that we take
112 * dev->event_lock here to avoid racing with input_event
113 * which may cause keys get "stuck".
114 */
115static void input_repeat_key(unsigned long data)
116{
117 struct input_dev *dev = (void *) data;
118 unsigned long flags;
119
120 spin_lock_irqsave(&dev->event_lock, flags);
121
122 if (test_bit(dev->repeat_key, dev->key) &&
123 is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
124
125 input_pass_event(dev, EV_KEY, dev->repeat_key, 2);
126
127 if (dev->sync) {
128 /*
129 * Only send SYN_REPORT if we are not in a middle
130 * of driver parsing a new hardware packet.
131 * Otherwise assume that the driver will send
132 * SYN_REPORT once it's done.
133 */
134 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
135 }
136
137 if (dev->rep[REP_PERIOD])
138 mod_timer(&dev->timer, jiffies +
139 msecs_to_jiffies(dev->rep[REP_PERIOD]));
140 }
141
142 spin_unlock_irqrestore(&dev->event_lock, flags);
143}
144
145static void input_start_autorepeat(struct input_dev *dev, int code)
146{
147 if (test_bit(EV_REP, dev->evbit) &&
148 dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
149 dev->timer.data) {
150 dev->repeat_key = code;
151 mod_timer(&dev->timer,
152 jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
153 }
154}
155
156static void input_stop_autorepeat(struct input_dev *dev)
157{
158 del_timer(&dev->timer);
159}
160
161#define INPUT_IGNORE_EVENT 0
162#define INPUT_PASS_TO_HANDLERS 1
163#define INPUT_PASS_TO_DEVICE 2
164#define INPUT_PASS_TO_ALL (INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
165
166static int input_handle_abs_event(struct input_dev *dev,
167 unsigned int code, int *pval)
168{
169 bool is_mt_event;
170 int *pold;
171
172 if (code == ABS_MT_SLOT) {
173 /*
174 * "Stage" the event; we'll flush it later, when we
175 * get actual touch data.
176 */
177 if (*pval >= 0 && *pval < dev->mtsize)
178 dev->slot = *pval;
179
180 return INPUT_IGNORE_EVENT;
181 }
182
183 is_mt_event = code >= ABS_MT_FIRST && code <= ABS_MT_LAST;
184
185 if (!is_mt_event) {
186 pold = &dev->absinfo[code].value;
187 } else if (dev->mt) {
188 struct input_mt_slot *mtslot = &dev->mt[dev->slot];
189 pold = &mtslot->abs[code - ABS_MT_FIRST];
190 } else {
191 /*
192 * Bypass filtering for multi-touch events when
193 * not employing slots.
194 */
195 pold = NULL;
196 }
197
198 if (pold) {
199 *pval = input_defuzz_abs_event(*pval, *pold,
200 dev->absinfo[code].fuzz);
201 if (*pold == *pval)
202 return INPUT_IGNORE_EVENT;
203
204 *pold = *pval;
205 }
206
207 /* Flush pending "slot" event */
208 if (is_mt_event && dev->slot != input_abs_get_val(dev, ABS_MT_SLOT)) {
209 input_abs_set_val(dev, ABS_MT_SLOT, dev->slot);
210 input_pass_event(dev, EV_ABS, ABS_MT_SLOT, dev->slot);
211 }
212
213 return INPUT_PASS_TO_HANDLERS;
214}
215
216static void input_handle_event(struct input_dev *dev,
217 unsigned int type, unsigned int code, int value)
218{
219 int disposition = INPUT_IGNORE_EVENT;
220
221 switch (type) {
222
223 case EV_SYN:
224 switch (code) {
225 case SYN_CONFIG:
226 disposition = INPUT_PASS_TO_ALL;
227 break;
228
229 case SYN_REPORT:
230 if (!dev->sync) {
231 dev->sync = true;
232 disposition = INPUT_PASS_TO_HANDLERS;
233 }
234 break;
235 case SYN_MT_REPORT:
236 dev->sync = false;
237 disposition = INPUT_PASS_TO_HANDLERS;
238 break;
239 }
240 break;
241
242 case EV_KEY:
243 if (is_event_supported(code, dev->keybit, KEY_MAX) &&
244 !!test_bit(code, dev->key) != value) {
245
246 if (value != 2) {
247 __change_bit(code, dev->key);
248 if (value)
249 input_start_autorepeat(dev, code);
250 else
251 input_stop_autorepeat(dev);
252 }
253
254 disposition = INPUT_PASS_TO_HANDLERS;
255 }
256 break;
257
258 case EV_SW:
259 if (is_event_supported(code, dev->swbit, SW_MAX) &&
260 !!test_bit(code, dev->sw) != value) {
261
262 __change_bit(code, dev->sw);
263 disposition = INPUT_PASS_TO_HANDLERS;
264 }
265 break;
266
267 case EV_ABS:
268 if (is_event_supported(code, dev->absbit, ABS_MAX))
269 disposition = input_handle_abs_event(dev, code, &value);
270
271 break;
272
273 case EV_REL:
274 if (is_event_supported(code, dev->relbit, REL_MAX) && value)
275 disposition = INPUT_PASS_TO_HANDLERS;
276
277 break;
278
279 case EV_MSC:
280 if (is_event_supported(code, dev->mscbit, MSC_MAX))
281 disposition = INPUT_PASS_TO_ALL;
282
283 break;
284
285 case EV_LED:
286 if (is_event_supported(code, dev->ledbit, LED_MAX) &&
287 !!test_bit(code, dev->led) != value) {
288
289 __change_bit(code, dev->led);
290 disposition = INPUT_PASS_TO_ALL;
291 }
292 break;
293
294 case EV_SND:
295 if (is_event_supported(code, dev->sndbit, SND_MAX)) {
296
297 if (!!test_bit(code, dev->snd) != !!value)
298 __change_bit(code, dev->snd);
299 disposition = INPUT_PASS_TO_ALL;
300 }
301 break;
302
303 case EV_REP:
304 if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
305 dev->rep[code] = value;
306 disposition = INPUT_PASS_TO_ALL;
307 }
308 break;
309
310 case EV_FF:
311 if (value >= 0)
312 disposition = INPUT_PASS_TO_ALL;
313 break;
314
315 case EV_PWR:
316 disposition = INPUT_PASS_TO_ALL;
317 break;
318 }
319
320 if (disposition != INPUT_IGNORE_EVENT && type != EV_SYN)
321 dev->sync = false;
322
323 if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
324 dev->event(dev, type, code, value);
325
326 if (disposition & INPUT_PASS_TO_HANDLERS)
327 input_pass_event(dev, type, code, value);
328}
329
330/**
331 * input_event() - report new input event
332 * @dev: device that generated the event
333 * @type: type of the event
334 * @code: event code
335 * @value: value of the event
336 *
337 * This function should be used by drivers implementing various input
338 * devices to report input events. See also input_inject_event().
339 *
340 * NOTE: input_event() may be safely used right after input device was
341 * allocated with input_allocate_device(), even before it is registered
342 * with input_register_device(), but the event will not reach any of the
343 * input handlers. Such early invocation of input_event() may be used
344 * to 'seed' initial state of a switch or initial position of absolute
345 * axis, etc.
346 */
347void input_event(struct input_dev *dev,
348 unsigned int type, unsigned int code, int value)
349{
350 unsigned long flags;
351
352 if (is_event_supported(type, dev->evbit, EV_MAX)) {
353
354 spin_lock_irqsave(&dev->event_lock, flags);
355 add_input_randomness(type, code, value);
356 input_handle_event(dev, type, code, value);
357 spin_unlock_irqrestore(&dev->event_lock, flags);
358 }
359}
360EXPORT_SYMBOL(input_event);
361
362/**
363 * input_inject_event() - send input event from input handler
364 * @handle: input handle to send event through
365 * @type: type of the event
366 * @code: event code
367 * @value: value of the event
368 *
369 * Similar to input_event() but will ignore event if device is
370 * "grabbed" and handle injecting event is not the one that owns
371 * the device.
372 */
373void input_inject_event(struct input_handle *handle,
374 unsigned int type, unsigned int code, int value)
375{
376 struct input_dev *dev = handle->dev;
377 struct input_handle *grab;
378 unsigned long flags;
379
380 if (is_event_supported(type, dev->evbit, EV_MAX)) {
381 spin_lock_irqsave(&dev->event_lock, flags);
382
383 rcu_read_lock();
384 grab = rcu_dereference(dev->grab);
385 if (!grab || grab == handle)
386 input_handle_event(dev, type, code, value);
387 rcu_read_unlock();
388
389 spin_unlock_irqrestore(&dev->event_lock, flags);
390 }
391}
392EXPORT_SYMBOL(input_inject_event);
393
394/**
395 * input_alloc_absinfo - allocates array of input_absinfo structs
396 * @dev: the input device emitting absolute events
397 *
398 * If the absinfo struct the caller asked for is already allocated, this
399 * functions will not do anything.
400 */
401void input_alloc_absinfo(struct input_dev *dev)
402{
403 if (!dev->absinfo)
404 dev->absinfo = kcalloc(ABS_CNT, sizeof(struct input_absinfo),
405 GFP_KERNEL);
406
407 WARN(!dev->absinfo, "%s(): kcalloc() failed?\n", __func__);
408}
409EXPORT_SYMBOL(input_alloc_absinfo);
410
411void input_set_abs_params(struct input_dev *dev, unsigned int axis,
412 int min, int max, int fuzz, int flat)
413{
414 struct input_absinfo *absinfo;
415
416 input_alloc_absinfo(dev);
417 if (!dev->absinfo)
418 return;
419
420 absinfo = &dev->absinfo[axis];
421 absinfo->minimum = min;
422 absinfo->maximum = max;
423 absinfo->fuzz = fuzz;
424 absinfo->flat = flat;
425
426 dev->absbit[BIT_WORD(axis)] |= BIT_MASK(axis);
427}
428EXPORT_SYMBOL(input_set_abs_params);
429
430
431/**
432 * input_grab_device - grabs device for exclusive use
433 * @handle: input handle that wants to own the device
434 *
435 * When a device is grabbed by an input handle all events generated by
436 * the device are delivered only to this handle. Also events injected
437 * by other input handles are ignored while device is grabbed.
438 */
439int input_grab_device(struct input_handle *handle)
440{
441 struct input_dev *dev = handle->dev;
442 int retval;
443
444 retval = mutex_lock_interruptible(&dev->mutex);
445 if (retval)
446 return retval;
447
448 if (dev->grab) {
449 retval = -EBUSY;
450 goto out;
451 }
452
453 rcu_assign_pointer(dev->grab, handle);
454
455 out:
456 mutex_unlock(&dev->mutex);
457 return retval;
458}
459EXPORT_SYMBOL(input_grab_device);
460
461static void __input_release_device(struct input_handle *handle)
462{
463 struct input_dev *dev = handle->dev;
464
465 if (dev->grab == handle) {
466 rcu_assign_pointer(dev->grab, NULL);
467 /* Make sure input_pass_event() notices that grab is gone */
468 synchronize_rcu();
469
470 list_for_each_entry(handle, &dev->h_list, d_node)
471 if (handle->open && handle->handler->start)
472 handle->handler->start(handle);
473 }
474}
475
476/**
477 * input_release_device - release previously grabbed device
478 * @handle: input handle that owns the device
479 *
480 * Releases previously grabbed device so that other input handles can
481 * start receiving input events. Upon release all handlers attached
482 * to the device have their start() method called so they have a change
483 * to synchronize device state with the rest of the system.
484 */
485void input_release_device(struct input_handle *handle)
486{
487 struct input_dev *dev = handle->dev;
488
489 mutex_lock(&dev->mutex);
490 __input_release_device(handle);
491 mutex_unlock(&dev->mutex);
492}
493EXPORT_SYMBOL(input_release_device);
494
495/**
496 * input_open_device - open input device
497 * @handle: handle through which device is being accessed
498 *
499 * This function should be called by input handlers when they
500 * want to start receive events from given input device.
501 */
502int input_open_device(struct input_handle *handle)
503{
504 struct input_dev *dev = handle->dev;
505 int retval;
506
507 retval = mutex_lock_interruptible(&dev->mutex);
508 if (retval)
509 return retval;
510
511 if (dev->going_away) {
512 retval = -ENODEV;
513 goto out;
514 }
515
516 handle->open++;
517
518 if (!dev->users++ && dev->open)
519 retval = dev->open(dev);
520
521 if (retval) {
522 dev->users--;
523 if (!--handle->open) {
524 /*
525 * Make sure we are not delivering any more events
526 * through this handle
527 */
528 synchronize_rcu();
529 }
530 }
531
532 out:
533 mutex_unlock(&dev->mutex);
534 return retval;
535}
536EXPORT_SYMBOL(input_open_device);
537
538int input_flush_device(struct input_handle *handle, struct file *file)
539{
540 struct input_dev *dev = handle->dev;
541 int retval;
542
543 retval = mutex_lock_interruptible(&dev->mutex);
544 if (retval)
545 return retval;
546
547 if (dev->flush)
548 retval = dev->flush(dev, file);
549
550 mutex_unlock(&dev->mutex);
551 return retval;
552}
553EXPORT_SYMBOL(input_flush_device);
554
555/**
556 * input_close_device - close input device
557 * @handle: handle through which device is being accessed
558 *
559 * This function should be called by input handlers when they
560 * want to stop receive events from given input device.
561 */
562void input_close_device(struct input_handle *handle)
563{
564 struct input_dev *dev = handle->dev;
565
566 mutex_lock(&dev->mutex);
567
568 __input_release_device(handle);
569
570 if (!--dev->users && dev->close)
571 dev->close(dev);
572
573 if (!--handle->open) {
574 /*
575 * synchronize_rcu() makes sure that input_pass_event()
576 * completed and that no more input events are delivered
577 * through this handle
578 */
579 synchronize_rcu();
580 }
581
582 mutex_unlock(&dev->mutex);
583}
584EXPORT_SYMBOL(input_close_device);
585
586/*
587 * Simulate keyup events for all keys that are marked as pressed.
588 * The function must be called with dev->event_lock held.
589 */
590static void input_dev_release_keys(struct input_dev *dev)
591{
592 int code;
593
594 if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
595 for (code = 0; code <= KEY_MAX; code++) {
596 if (is_event_supported(code, dev->keybit, KEY_MAX) &&
597 __test_and_clear_bit(code, dev->key)) {
598 input_pass_event(dev, EV_KEY, code, 0);
599 }
600 }
601 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
602 }
603}
604
605/*
606 * Prepare device for unregistering
607 */
608static void input_disconnect_device(struct input_dev *dev)
609{
610 struct input_handle *handle;
611
612 /*
613 * Mark device as going away. Note that we take dev->mutex here
614 * not to protect access to dev->going_away but rather to ensure
615 * that there are no threads in the middle of input_open_device()
616 */
617 mutex_lock(&dev->mutex);
618 dev->going_away = true;
619 mutex_unlock(&dev->mutex);
620
621 spin_lock_irq(&dev->event_lock);
622
623 /*
624 * Simulate keyup events for all pressed keys so that handlers
625 * are not left with "stuck" keys. The driver may continue
626 * generate events even after we done here but they will not
627 * reach any handlers.
628 */
629 input_dev_release_keys(dev);
630
631 list_for_each_entry(handle, &dev->h_list, d_node)
632 handle->open = 0;
633
634 spin_unlock_irq(&dev->event_lock);
635}
636
637/**
638 * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
639 * @ke: keymap entry containing scancode to be converted.
640 * @scancode: pointer to the location where converted scancode should
641 * be stored.
642 *
643 * This function is used to convert scancode stored in &struct keymap_entry
644 * into scalar form understood by legacy keymap handling methods. These
645 * methods expect scancodes to be represented as 'unsigned int'.
646 */
647int input_scancode_to_scalar(const struct input_keymap_entry *ke,
648 unsigned int *scancode)
649{
650 switch (ke->len) {
651 case 1:
652 *scancode = *((u8 *)ke->scancode);
653 break;
654
655 case 2:
656 *scancode = *((u16 *)ke->scancode);
657 break;
658
659 case 4:
660 *scancode = *((u32 *)ke->scancode);
661 break;
662
663 default:
664 return -EINVAL;
665 }
666
667 return 0;
668}
669EXPORT_SYMBOL(input_scancode_to_scalar);
670
671/*
672 * Those routines handle the default case where no [gs]etkeycode() is
673 * defined. In this case, an array indexed by the scancode is used.
674 */
675
676static unsigned int input_fetch_keycode(struct input_dev *dev,
677 unsigned int index)
678{
679 switch (dev->keycodesize) {
680 case 1:
681 return ((u8 *)dev->keycode)[index];
682
683 case 2:
684 return ((u16 *)dev->keycode)[index];
685
686 default:
687 return ((u32 *)dev->keycode)[index];
688 }
689}
690
691static int input_default_getkeycode(struct input_dev *dev,
692 struct input_keymap_entry *ke)
693{
694 unsigned int index;
695 int error;
696
697 if (!dev->keycodesize)
698 return -EINVAL;
699
700 if (ke->flags & INPUT_KEYMAP_BY_INDEX)
701 index = ke->index;
702 else {
703 error = input_scancode_to_scalar(ke, &index);
704 if (error)
705 return error;
706 }
707
708 if (index >= dev->keycodemax)
709 return -EINVAL;
710
711 ke->keycode = input_fetch_keycode(dev, index);
712 ke->index = index;
713 ke->len = sizeof(index);
714 memcpy(ke->scancode, &index, sizeof(index));
715
716 return 0;
717}
718
719static int input_default_setkeycode(struct input_dev *dev,
720 const struct input_keymap_entry *ke,
721 unsigned int *old_keycode)
722{
723 unsigned int index;
724 int error;
725 int i;
726
727 if (!dev->keycodesize)
728 return -EINVAL;
729
730 if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
731 index = ke->index;
732 } else {
733 error = input_scancode_to_scalar(ke, &index);
734 if (error)
735 return error;
736 }
737
738 if (index >= dev->keycodemax)
739 return -EINVAL;
740
741 if (dev->keycodesize < sizeof(ke->keycode) &&
742 (ke->keycode >> (dev->keycodesize * 8)))
743 return -EINVAL;
744
745 switch (dev->keycodesize) {
746 case 1: {
747 u8 *k = (u8 *)dev->keycode;
748 *old_keycode = k[index];
749 k[index] = ke->keycode;
750 break;
751 }
752 case 2: {
753 u16 *k = (u16 *)dev->keycode;
754 *old_keycode = k[index];
755 k[index] = ke->keycode;
756 break;
757 }
758 default: {
759 u32 *k = (u32 *)dev->keycode;
760 *old_keycode = k[index];
761 k[index] = ke->keycode;
762 break;
763 }
764 }
765
766 __clear_bit(*old_keycode, dev->keybit);
767 __set_bit(ke->keycode, dev->keybit);
768
769 for (i = 0; i < dev->keycodemax; i++) {
770 if (input_fetch_keycode(dev, i) == *old_keycode) {
771 __set_bit(*old_keycode, dev->keybit);
772 break; /* Setting the bit twice is useless, so break */
773 }
774 }
775
776 return 0;
777}
778
779/**
780 * input_get_keycode - retrieve keycode currently mapped to a given scancode
781 * @dev: input device which keymap is being queried
782 * @ke: keymap entry
783 *
784 * This function should be called by anyone interested in retrieving current
785 * keymap. Presently evdev handlers use it.
786 */
787int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
788{
789 unsigned long flags;
790 int retval;
791
792 spin_lock_irqsave(&dev->event_lock, flags);
793 retval = dev->getkeycode(dev, ke);
794 spin_unlock_irqrestore(&dev->event_lock, flags);
795
796 return retval;
797}
798EXPORT_SYMBOL(input_get_keycode);
799
800/**
801 * input_set_keycode - attribute a keycode to a given scancode
802 * @dev: input device which keymap is being updated
803 * @ke: new keymap entry
804 *
805 * This function should be called by anyone needing to update current
806 * keymap. Presently keyboard and evdev handlers use it.
807 */
808int input_set_keycode(struct input_dev *dev,
809 const struct input_keymap_entry *ke)
810{
811 unsigned long flags;
812 unsigned int old_keycode;
813 int retval;
814
815 if (ke->keycode > KEY_MAX)
816 return -EINVAL;
817
818 spin_lock_irqsave(&dev->event_lock, flags);
819
820 retval = dev->setkeycode(dev, ke, &old_keycode);
821 if (retval)
822 goto out;
823
824 /* Make sure KEY_RESERVED did not get enabled. */
825 __clear_bit(KEY_RESERVED, dev->keybit);
826
827 /*
828 * Simulate keyup event if keycode is not present
829 * in the keymap anymore
830 */
831 if (test_bit(EV_KEY, dev->evbit) &&
832 !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
833 __test_and_clear_bit(old_keycode, dev->key)) {
834
835 input_pass_event(dev, EV_KEY, old_keycode, 0);
836 if (dev->sync)
837 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
838 }
839
840 out:
841 spin_unlock_irqrestore(&dev->event_lock, flags);
842
843 return retval;
844}
845EXPORT_SYMBOL(input_set_keycode);
846
847#define MATCH_BIT(bit, max) \
848 for (i = 0; i < BITS_TO_LONGS(max); i++) \
849 if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \
850 break; \
851 if (i != BITS_TO_LONGS(max)) \
852 continue;
853
854static const struct input_device_id *input_match_device(struct input_handler *handler,
855 struct input_dev *dev)
856{
857 const struct input_device_id *id;
858 int i;
859
860 for (id = handler->id_table; id->flags || id->driver_info; id++) {
861
862 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
863 if (id->bustype != dev->id.bustype)
864 continue;
865
866 if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
867 if (id->vendor != dev->id.vendor)
868 continue;
869
870 if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
871 if (id->product != dev->id.product)
872 continue;
873
874 if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
875 if (id->version != dev->id.version)
876 continue;
877
878 MATCH_BIT(evbit, EV_MAX);
879 MATCH_BIT(keybit, KEY_MAX);
880 MATCH_BIT(relbit, REL_MAX);
881 MATCH_BIT(absbit, ABS_MAX);
882 MATCH_BIT(mscbit, MSC_MAX);
883 MATCH_BIT(ledbit, LED_MAX);
884 MATCH_BIT(sndbit, SND_MAX);
885 MATCH_BIT(ffbit, FF_MAX);
886 MATCH_BIT(swbit, SW_MAX);
887
888 if (!handler->match || handler->match(handler, dev))
889 return id;
890 }
891
892 return NULL;
893}
894
895static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
896{
897 const struct input_device_id *id;
898 int error;
899
900 id = input_match_device(handler, dev);
901 if (!id)
902 return -ENODEV;
903
904 error = handler->connect(handler, dev, id);
905 if (error && error != -ENODEV)
906 pr_err("failed to attach handler %s to device %s, error: %d\n",
907 handler->name, kobject_name(&dev->dev.kobj), error);
908
909 return error;
910}
911
912#ifdef CONFIG_COMPAT
913
914static int input_bits_to_string(char *buf, int buf_size,
915 unsigned long bits, bool skip_empty)
916{
917 int len = 0;
918
919 if (INPUT_COMPAT_TEST) {
920 u32 dword = bits >> 32;
921 if (dword || !skip_empty)
922 len += snprintf(buf, buf_size, "%x ", dword);
923
924 dword = bits & 0xffffffffUL;
925 if (dword || !skip_empty || len)
926 len += snprintf(buf + len, max(buf_size - len, 0),
927 "%x", dword);
928 } else {
929 if (bits || !skip_empty)
930 len += snprintf(buf, buf_size, "%lx", bits);
931 }
932
933 return len;
934}
935
936#else /* !CONFIG_COMPAT */
937
938static int input_bits_to_string(char *buf, int buf_size,
939 unsigned long bits, bool skip_empty)
940{
941 return bits || !skip_empty ?
942 snprintf(buf, buf_size, "%lx", bits) : 0;
943}
944
945#endif
946
947#ifdef CONFIG_PROC_FS
948
949static struct proc_dir_entry *proc_bus_input_dir;
950static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
951static int input_devices_state;
952
953static inline void input_wakeup_procfs_readers(void)
954{
955 input_devices_state++;
956 wake_up(&input_devices_poll_wait);
957}
958
959static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
960{
961 poll_wait(file, &input_devices_poll_wait, wait);
962 if (file->f_version != input_devices_state) {
963 file->f_version = input_devices_state;
964 return POLLIN | POLLRDNORM;
965 }
966
967 return 0;
968}
969
970union input_seq_state {
971 struct {
972 unsigned short pos;
973 bool mutex_acquired;
974 };
975 void *p;
976};
977
978static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
979{
980 union input_seq_state *state = (union input_seq_state *)&seq->private;
981 int error;
982
983 /* We need to fit into seq->private pointer */
984 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
985
986 error = mutex_lock_interruptible(&input_mutex);
987 if (error) {
988 state->mutex_acquired = false;
989 return ERR_PTR(error);
990 }
991
992 state->mutex_acquired = true;
993
994 return seq_list_start(&input_dev_list, *pos);
995}
996
997static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
998{
999 return seq_list_next(v, &input_dev_list, pos);
1000}
1001
1002static void input_seq_stop(struct seq_file *seq, void *v)
1003{
1004 union input_seq_state *state = (union input_seq_state *)&seq->private;
1005
1006 if (state->mutex_acquired)
1007 mutex_unlock(&input_mutex);
1008}
1009
1010static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
1011 unsigned long *bitmap, int max)
1012{
1013 int i;
1014 bool skip_empty = true;
1015 char buf[18];
1016
1017 seq_printf(seq, "B: %s=", name);
1018
1019 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1020 if (input_bits_to_string(buf, sizeof(buf),
1021 bitmap[i], skip_empty)) {
1022 skip_empty = false;
1023 seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
1024 }
1025 }
1026
1027 /*
1028 * If no output was produced print a single 0.
1029 */
1030 if (skip_empty)
1031 seq_puts(seq, "0");
1032
1033 seq_putc(seq, '\n');
1034}
1035
1036static int input_devices_seq_show(struct seq_file *seq, void *v)
1037{
1038 struct input_dev *dev = container_of(v, struct input_dev, node);
1039 const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1040 struct input_handle *handle;
1041
1042 seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
1043 dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
1044
1045 seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
1046 seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
1047 seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
1048 seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1049 seq_printf(seq, "H: Handlers=");
1050
1051 list_for_each_entry(handle, &dev->h_list, d_node)
1052 seq_printf(seq, "%s ", handle->name);
1053 seq_putc(seq, '\n');
1054
1055 input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
1056
1057 input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
1058 if (test_bit(EV_KEY, dev->evbit))
1059 input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
1060 if (test_bit(EV_REL, dev->evbit))
1061 input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
1062 if (test_bit(EV_ABS, dev->evbit))
1063 input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
1064 if (test_bit(EV_MSC, dev->evbit))
1065 input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
1066 if (test_bit(EV_LED, dev->evbit))
1067 input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
1068 if (test_bit(EV_SND, dev->evbit))
1069 input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
1070 if (test_bit(EV_FF, dev->evbit))
1071 input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
1072 if (test_bit(EV_SW, dev->evbit))
1073 input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
1074
1075 seq_putc(seq, '\n');
1076
1077 kfree(path);
1078 return 0;
1079}
1080
1081static const struct seq_operations input_devices_seq_ops = {
1082 .start = input_devices_seq_start,
1083 .next = input_devices_seq_next,
1084 .stop = input_seq_stop,
1085 .show = input_devices_seq_show,
1086};
1087
1088static int input_proc_devices_open(struct inode *inode, struct file *file)
1089{
1090 return seq_open(file, &input_devices_seq_ops);
1091}
1092
1093static const struct file_operations input_devices_fileops = {
1094 .owner = THIS_MODULE,
1095 .open = input_proc_devices_open,
1096 .poll = input_proc_devices_poll,
1097 .read = seq_read,
1098 .llseek = seq_lseek,
1099 .release = seq_release,
1100};
1101
1102static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
1103{
1104 union input_seq_state *state = (union input_seq_state *)&seq->private;
1105 int error;
1106
1107 /* We need to fit into seq->private pointer */
1108 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1109
1110 error = mutex_lock_interruptible(&input_mutex);
1111 if (error) {
1112 state->mutex_acquired = false;
1113 return ERR_PTR(error);
1114 }
1115
1116 state->mutex_acquired = true;
1117 state->pos = *pos;
1118
1119 return seq_list_start(&input_handler_list, *pos);
1120}
1121
1122static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1123{
1124 union input_seq_state *state = (union input_seq_state *)&seq->private;
1125
1126 state->pos = *pos + 1;
1127 return seq_list_next(v, &input_handler_list, pos);
1128}
1129
1130static int input_handlers_seq_show(struct seq_file *seq, void *v)
1131{
1132 struct input_handler *handler = container_of(v, struct input_handler, node);
1133 union input_seq_state *state = (union input_seq_state *)&seq->private;
1134
1135 seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
1136 if (handler->filter)
1137 seq_puts(seq, " (filter)");
1138 if (handler->fops)
1139 seq_printf(seq, " Minor=%d", handler->minor);
1140 seq_putc(seq, '\n');
1141
1142 return 0;
1143}
1144
1145static const struct seq_operations input_handlers_seq_ops = {
1146 .start = input_handlers_seq_start,
1147 .next = input_handlers_seq_next,
1148 .stop = input_seq_stop,
1149 .show = input_handlers_seq_show,
1150};
1151
1152static int input_proc_handlers_open(struct inode *inode, struct file *file)
1153{
1154 return seq_open(file, &input_handlers_seq_ops);
1155}
1156
1157static const struct file_operations input_handlers_fileops = {
1158 .owner = THIS_MODULE,
1159 .open = input_proc_handlers_open,
1160 .read = seq_read,
1161 .llseek = seq_lseek,
1162 .release = seq_release,
1163};
1164
1165static int __init input_proc_init(void)
1166{
1167 struct proc_dir_entry *entry;
1168
1169 proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1170 if (!proc_bus_input_dir)
1171 return -ENOMEM;
1172
1173 entry = proc_create("devices", 0, proc_bus_input_dir,
1174 &input_devices_fileops);
1175 if (!entry)
1176 goto fail1;
1177
1178 entry = proc_create("handlers", 0, proc_bus_input_dir,
1179 &input_handlers_fileops);
1180 if (!entry)
1181 goto fail2;
1182
1183 return 0;
1184
1185 fail2: remove_proc_entry("devices", proc_bus_input_dir);
1186 fail1: remove_proc_entry("bus/input", NULL);
1187 return -ENOMEM;
1188}
1189
1190static void input_proc_exit(void)
1191{
1192 remove_proc_entry("devices", proc_bus_input_dir);
1193 remove_proc_entry("handlers", proc_bus_input_dir);
1194 remove_proc_entry("bus/input", NULL);
1195}
1196
1197#else /* !CONFIG_PROC_FS */
1198static inline void input_wakeup_procfs_readers(void) { }
1199static inline int input_proc_init(void) { return 0; }
1200static inline void input_proc_exit(void) { }
1201#endif
1202
1203#define INPUT_DEV_STRING_ATTR_SHOW(name) \
1204static ssize_t input_dev_show_##name(struct device *dev, \
1205 struct device_attribute *attr, \
1206 char *buf) \
1207{ \
1208 struct input_dev *input_dev = to_input_dev(dev); \
1209 \
1210 return scnprintf(buf, PAGE_SIZE, "%s\n", \
1211 input_dev->name ? input_dev->name : ""); \
1212} \
1213static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1214
1215INPUT_DEV_STRING_ATTR_SHOW(name);
1216INPUT_DEV_STRING_ATTR_SHOW(phys);
1217INPUT_DEV_STRING_ATTR_SHOW(uniq);
1218
1219static int input_print_modalias_bits(char *buf, int size,
1220 char name, unsigned long *bm,
1221 unsigned int min_bit, unsigned int max_bit)
1222{
1223 int len = 0, i;
1224
1225 len += snprintf(buf, max(size, 0), "%c", name);
1226 for (i = min_bit; i < max_bit; i++)
1227 if (bm[BIT_WORD(i)] & BIT_MASK(i))
1228 len += snprintf(buf + len, max(size - len, 0), "%X,", i);
1229 return len;
1230}
1231
1232static int input_print_modalias(char *buf, int size, struct input_dev *id,
1233 int add_cr)
1234{
1235 int len;
1236
1237 len = snprintf(buf, max(size, 0),
1238 "input:b%04Xv%04Xp%04Xe%04X-",
1239 id->id.bustype, id->id.vendor,
1240 id->id.product, id->id.version);
1241
1242 len += input_print_modalias_bits(buf + len, size - len,
1243 'e', id->evbit, 0, EV_MAX);
1244 len += input_print_modalias_bits(buf + len, size - len,
1245 'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1246 len += input_print_modalias_bits(buf + len, size - len,
1247 'r', id->relbit, 0, REL_MAX);
1248 len += input_print_modalias_bits(buf + len, size - len,
1249 'a', id->absbit, 0, ABS_MAX);
1250 len += input_print_modalias_bits(buf + len, size - len,
1251 'm', id->mscbit, 0, MSC_MAX);
1252 len += input_print_modalias_bits(buf + len, size - len,
1253 'l', id->ledbit, 0, LED_MAX);
1254 len += input_print_modalias_bits(buf + len, size - len,
1255 's', id->sndbit, 0, SND_MAX);
1256 len += input_print_modalias_bits(buf + len, size - len,
1257 'f', id->ffbit, 0, FF_MAX);
1258 len += input_print_modalias_bits(buf + len, size - len,
1259 'w', id->swbit, 0, SW_MAX);
1260
1261 if (add_cr)
1262 len += snprintf(buf + len, max(size - len, 0), "\n");
1263
1264 return len;
1265}
1266
1267static ssize_t input_dev_show_modalias(struct device *dev,
1268 struct device_attribute *attr,
1269 char *buf)
1270{
1271 struct input_dev *id = to_input_dev(dev);
1272 ssize_t len;
1273
1274 len = input_print_modalias(buf, PAGE_SIZE, id, 1);
1275
1276 return min_t(int, len, PAGE_SIZE);
1277}
1278static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1279
1280static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1281 int max, int add_cr);
1282
1283static ssize_t input_dev_show_properties(struct device *dev,
1284 struct device_attribute *attr,
1285 char *buf)
1286{
1287 struct input_dev *input_dev = to_input_dev(dev);
1288 int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
1289 INPUT_PROP_MAX, true);
1290 return min_t(int, len, PAGE_SIZE);
1291}
1292static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
1293
1294static struct attribute *input_dev_attrs[] = {
1295 &dev_attr_name.attr,
1296 &dev_attr_phys.attr,
1297 &dev_attr_uniq.attr,
1298 &dev_attr_modalias.attr,
1299 &dev_attr_properties.attr,
1300 NULL
1301};
1302
1303static struct attribute_group input_dev_attr_group = {
1304 .attrs = input_dev_attrs,
1305};
1306
1307#define INPUT_DEV_ID_ATTR(name) \
1308static ssize_t input_dev_show_id_##name(struct device *dev, \
1309 struct device_attribute *attr, \
1310 char *buf) \
1311{ \
1312 struct input_dev *input_dev = to_input_dev(dev); \
1313 return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name); \
1314} \
1315static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1316
1317INPUT_DEV_ID_ATTR(bustype);
1318INPUT_DEV_ID_ATTR(vendor);
1319INPUT_DEV_ID_ATTR(product);
1320INPUT_DEV_ID_ATTR(version);
1321
1322static struct attribute *input_dev_id_attrs[] = {
1323 &dev_attr_bustype.attr,
1324 &dev_attr_vendor.attr,
1325 &dev_attr_product.attr,
1326 &dev_attr_version.attr,
1327 NULL
1328};
1329
1330static struct attribute_group input_dev_id_attr_group = {
1331 .name = "id",
1332 .attrs = input_dev_id_attrs,
1333};
1334
1335static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1336 int max, int add_cr)
1337{
1338 int i;
1339 int len = 0;
1340 bool skip_empty = true;
1341
1342 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1343 len += input_bits_to_string(buf + len, max(buf_size - len, 0),
1344 bitmap[i], skip_empty);
1345 if (len) {
1346 skip_empty = false;
1347 if (i > 0)
1348 len += snprintf(buf + len, max(buf_size - len, 0), " ");
1349 }
1350 }
1351
1352 /*
1353 * If no output was produced print a single 0.
1354 */
1355 if (len == 0)
1356 len = snprintf(buf, buf_size, "%d", 0);
1357
1358 if (add_cr)
1359 len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1360
1361 return len;
1362}
1363
1364#define INPUT_DEV_CAP_ATTR(ev, bm) \
1365static ssize_t input_dev_show_cap_##bm(struct device *dev, \
1366 struct device_attribute *attr, \
1367 char *buf) \
1368{ \
1369 struct input_dev *input_dev = to_input_dev(dev); \
1370 int len = input_print_bitmap(buf, PAGE_SIZE, \
1371 input_dev->bm##bit, ev##_MAX, \
1372 true); \
1373 return min_t(int, len, PAGE_SIZE); \
1374} \
1375static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1376
1377INPUT_DEV_CAP_ATTR(EV, ev);
1378INPUT_DEV_CAP_ATTR(KEY, key);
1379INPUT_DEV_CAP_ATTR(REL, rel);
1380INPUT_DEV_CAP_ATTR(ABS, abs);
1381INPUT_DEV_CAP_ATTR(MSC, msc);
1382INPUT_DEV_CAP_ATTR(LED, led);
1383INPUT_DEV_CAP_ATTR(SND, snd);
1384INPUT_DEV_CAP_ATTR(FF, ff);
1385INPUT_DEV_CAP_ATTR(SW, sw);
1386
1387static struct attribute *input_dev_caps_attrs[] = {
1388 &dev_attr_ev.attr,
1389 &dev_attr_key.attr,
1390 &dev_attr_rel.attr,
1391 &dev_attr_abs.attr,
1392 &dev_attr_msc.attr,
1393 &dev_attr_led.attr,
1394 &dev_attr_snd.attr,
1395 &dev_attr_ff.attr,
1396 &dev_attr_sw.attr,
1397 NULL
1398};
1399
1400static struct attribute_group input_dev_caps_attr_group = {
1401 .name = "capabilities",
1402 .attrs = input_dev_caps_attrs,
1403};
1404
1405static const struct attribute_group *input_dev_attr_groups[] = {
1406 &input_dev_attr_group,
1407 &input_dev_id_attr_group,
1408 &input_dev_caps_attr_group,
1409 NULL
1410};
1411
1412static void input_dev_release(struct device *device)
1413{
1414 struct input_dev *dev = to_input_dev(device);
1415
1416 input_ff_destroy(dev);
1417 input_mt_destroy_slots(dev);
1418 kfree(dev->absinfo);
1419 kfree(dev);
1420
1421 module_put(THIS_MODULE);
1422}
1423
1424/*
1425 * Input uevent interface - loading event handlers based on
1426 * device bitfields.
1427 */
1428static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1429 const char *name, unsigned long *bitmap, int max)
1430{
1431 int len;
1432
1433 if (add_uevent_var(env, "%s", name))
1434 return -ENOMEM;
1435
1436 len = input_print_bitmap(&env->buf[env->buflen - 1],
1437 sizeof(env->buf) - env->buflen,
1438 bitmap, max, false);
1439 if (len >= (sizeof(env->buf) - env->buflen))
1440 return -ENOMEM;
1441
1442 env->buflen += len;
1443 return 0;
1444}
1445
1446static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1447 struct input_dev *dev)
1448{
1449 int len;
1450
1451 if (add_uevent_var(env, "MODALIAS="))
1452 return -ENOMEM;
1453
1454 len = input_print_modalias(&env->buf[env->buflen - 1],
1455 sizeof(env->buf) - env->buflen,
1456 dev, 0);
1457 if (len >= (sizeof(env->buf) - env->buflen))
1458 return -ENOMEM;
1459
1460 env->buflen += len;
1461 return 0;
1462}
1463
1464#define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \
1465 do { \
1466 int err = add_uevent_var(env, fmt, val); \
1467 if (err) \
1468 return err; \
1469 } while (0)
1470
1471#define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max) \
1472 do { \
1473 int err = input_add_uevent_bm_var(env, name, bm, max); \
1474 if (err) \
1475 return err; \
1476 } while (0)
1477
1478#define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \
1479 do { \
1480 int err = input_add_uevent_modalias_var(env, dev); \
1481 if (err) \
1482 return err; \
1483 } while (0)
1484
1485static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
1486{
1487 struct input_dev *dev = to_input_dev(device);
1488
1489 INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1490 dev->id.bustype, dev->id.vendor,
1491 dev->id.product, dev->id.version);
1492 if (dev->name)
1493 INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1494 if (dev->phys)
1495 INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1496 if (dev->uniq)
1497 INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1498
1499 INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
1500
1501 INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1502 if (test_bit(EV_KEY, dev->evbit))
1503 INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1504 if (test_bit(EV_REL, dev->evbit))
1505 INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1506 if (test_bit(EV_ABS, dev->evbit))
1507 INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1508 if (test_bit(EV_MSC, dev->evbit))
1509 INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1510 if (test_bit(EV_LED, dev->evbit))
1511 INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1512 if (test_bit(EV_SND, dev->evbit))
1513 INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1514 if (test_bit(EV_FF, dev->evbit))
1515 INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1516 if (test_bit(EV_SW, dev->evbit))
1517 INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1518
1519 INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1520
1521 return 0;
1522}
1523
1524#define INPUT_DO_TOGGLE(dev, type, bits, on) \
1525 do { \
1526 int i; \
1527 bool active; \
1528 \
1529 if (!test_bit(EV_##type, dev->evbit)) \
1530 break; \
1531 \
1532 for (i = 0; i < type##_MAX; i++) { \
1533 if (!test_bit(i, dev->bits##bit)) \
1534 continue; \
1535 \
1536 active = test_bit(i, dev->bits); \
1537 if (!active && !on) \
1538 continue; \
1539 \
1540 dev->event(dev, EV_##type, i, on ? active : 0); \
1541 } \
1542 } while (0)
1543
1544static void input_dev_toggle(struct input_dev *dev, bool activate)
1545{
1546 if (!dev->event)
1547 return;
1548
1549 INPUT_DO_TOGGLE(dev, LED, led, activate);
1550 INPUT_DO_TOGGLE(dev, SND, snd, activate);
1551
1552 if (activate && test_bit(EV_REP, dev->evbit)) {
1553 dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1554 dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1555 }
1556}
1557
1558/**
1559 * input_reset_device() - reset/restore the state of input device
1560 * @dev: input device whose state needs to be reset
1561 *
1562 * This function tries to reset the state of an opened input device and
1563 * bring internal state and state if the hardware in sync with each other.
1564 * We mark all keys as released, restore LED state, repeat rate, etc.
1565 */
1566void input_reset_device(struct input_dev *dev)
1567{
1568 mutex_lock(&dev->mutex);
1569
1570 if (dev->users) {
1571 input_dev_toggle(dev, true);
1572
1573 /*
1574 * Keys that have been pressed at suspend time are unlikely
1575 * to be still pressed when we resume.
1576 */
1577 spin_lock_irq(&dev->event_lock);
1578 input_dev_release_keys(dev);
1579 spin_unlock_irq(&dev->event_lock);
1580 }
1581
1582 mutex_unlock(&dev->mutex);
1583}
1584EXPORT_SYMBOL(input_reset_device);
1585
1586#ifdef CONFIG_PM
1587static int input_dev_suspend(struct device *dev)
1588{
1589 struct input_dev *input_dev = to_input_dev(dev);
1590
1591 mutex_lock(&input_dev->mutex);
1592
1593 if (input_dev->users)
1594 input_dev_toggle(input_dev, false);
1595
1596 mutex_unlock(&input_dev->mutex);
1597
1598 return 0;
1599}
1600
1601static int input_dev_resume(struct device *dev)
1602{
1603 struct input_dev *input_dev = to_input_dev(dev);
1604
1605 input_reset_device(input_dev);
1606
1607 return 0;
1608}
1609
1610static const struct dev_pm_ops input_dev_pm_ops = {
1611 .suspend = input_dev_suspend,
1612 .resume = input_dev_resume,
1613 .poweroff = input_dev_suspend,
1614 .restore = input_dev_resume,
1615};
1616#endif /* CONFIG_PM */
1617
1618static struct device_type input_dev_type = {
1619 .groups = input_dev_attr_groups,
1620 .release = input_dev_release,
1621 .uevent = input_dev_uevent,
1622#ifdef CONFIG_PM
1623 .pm = &input_dev_pm_ops,
1624#endif
1625};
1626
1627static char *input_devnode(struct device *dev, mode_t *mode)
1628{
1629 return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
1630}
1631
1632struct class input_class = {
1633 .name = "input",
1634 .devnode = input_devnode,
1635};
1636EXPORT_SYMBOL_GPL(input_class);
1637
1638/**
1639 * input_allocate_device - allocate memory for new input device
1640 *
1641 * Returns prepared struct input_dev or NULL.
1642 *
1643 * NOTE: Use input_free_device() to free devices that have not been
1644 * registered; input_unregister_device() should be used for already
1645 * registered devices.
1646 */
1647struct input_dev *input_allocate_device(void)
1648{
1649 struct input_dev *dev;
1650
1651 dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
1652 if (dev) {
1653 dev->dev.type = &input_dev_type;
1654 dev->dev.class = &input_class;
1655 device_initialize(&dev->dev);
1656 mutex_init(&dev->mutex);
1657 spin_lock_init(&dev->event_lock);
1658 INIT_LIST_HEAD(&dev->h_list);
1659 INIT_LIST_HEAD(&dev->node);
1660
1661 __module_get(THIS_MODULE);
1662 }
1663
1664 return dev;
1665}
1666EXPORT_SYMBOL(input_allocate_device);
1667
1668/**
1669 * input_free_device - free memory occupied by input_dev structure
1670 * @dev: input device to free
1671 *
1672 * This function should only be used if input_register_device()
1673 * was not called yet or if it failed. Once device was registered
1674 * use input_unregister_device() and memory will be freed once last
1675 * reference to the device is dropped.
1676 *
1677 * Device should be allocated by input_allocate_device().
1678 *
1679 * NOTE: If there are references to the input device then memory
1680 * will not be freed until last reference is dropped.
1681 */
1682void input_free_device(struct input_dev *dev)
1683{
1684 if (dev)
1685 input_put_device(dev);
1686}
1687EXPORT_SYMBOL(input_free_device);
1688
1689/**
1690 * input_set_capability - mark device as capable of a certain event
1691 * @dev: device that is capable of emitting or accepting event
1692 * @type: type of the event (EV_KEY, EV_REL, etc...)
1693 * @code: event code
1694 *
1695 * In addition to setting up corresponding bit in appropriate capability
1696 * bitmap the function also adjusts dev->evbit.
1697 */
1698void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
1699{
1700 switch (type) {
1701 case EV_KEY:
1702 __set_bit(code, dev->keybit);
1703 break;
1704
1705 case EV_REL:
1706 __set_bit(code, dev->relbit);
1707 break;
1708
1709 case EV_ABS:
1710 __set_bit(code, dev->absbit);
1711 break;
1712
1713 case EV_MSC:
1714 __set_bit(code, dev->mscbit);
1715 break;
1716
1717 case EV_SW:
1718 __set_bit(code, dev->swbit);
1719 break;
1720
1721 case EV_LED:
1722 __set_bit(code, dev->ledbit);
1723 break;
1724
1725 case EV_SND:
1726 __set_bit(code, dev->sndbit);
1727 break;
1728
1729 case EV_FF:
1730 __set_bit(code, dev->ffbit);
1731 break;
1732
1733 case EV_PWR:
1734 /* do nothing */
1735 break;
1736
1737 default:
1738 pr_err("input_set_capability: unknown type %u (code %u)\n",
1739 type, code);
1740 dump_stack();
1741 return;
1742 }
1743
1744 __set_bit(type, dev->evbit);
1745}
1746EXPORT_SYMBOL(input_set_capability);
1747
1748static unsigned int input_estimate_events_per_packet(struct input_dev *dev)
1749{
1750 int mt_slots;
1751 int i;
1752 unsigned int events;
1753
1754 if (dev->mtsize) {
1755 mt_slots = dev->mtsize;
1756 } else if (test_bit(ABS_MT_TRACKING_ID, dev->absbit)) {
1757 mt_slots = dev->absinfo[ABS_MT_TRACKING_ID].maximum -
1758 dev->absinfo[ABS_MT_TRACKING_ID].minimum + 1,
1759 mt_slots = clamp(mt_slots, 2, 32);
1760 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
1761 mt_slots = 2;
1762 } else {
1763 mt_slots = 0;
1764 }
1765
1766 events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */
1767
1768 for (i = 0; i < ABS_CNT; i++) {
1769 if (test_bit(i, dev->absbit)) {
1770 if (input_is_mt_axis(i))
1771 events += mt_slots;
1772 else
1773 events++;
1774 }
1775 }
1776
1777 for (i = 0; i < REL_CNT; i++)
1778 if (test_bit(i, dev->relbit))
1779 events++;
1780
1781 return events;
1782}
1783
1784#define INPUT_CLEANSE_BITMASK(dev, type, bits) \
1785 do { \
1786 if (!test_bit(EV_##type, dev->evbit)) \
1787 memset(dev->bits##bit, 0, \
1788 sizeof(dev->bits##bit)); \
1789 } while (0)
1790
1791static void input_cleanse_bitmasks(struct input_dev *dev)
1792{
1793 INPUT_CLEANSE_BITMASK(dev, KEY, key);
1794 INPUT_CLEANSE_BITMASK(dev, REL, rel);
1795 INPUT_CLEANSE_BITMASK(dev, ABS, abs);
1796 INPUT_CLEANSE_BITMASK(dev, MSC, msc);
1797 INPUT_CLEANSE_BITMASK(dev, LED, led);
1798 INPUT_CLEANSE_BITMASK(dev, SND, snd);
1799 INPUT_CLEANSE_BITMASK(dev, FF, ff);
1800 INPUT_CLEANSE_BITMASK(dev, SW, sw);
1801}
1802
1803/**
1804 * input_register_device - register device with input core
1805 * @dev: device to be registered
1806 *
1807 * This function registers device with input core. The device must be
1808 * allocated with input_allocate_device() and all it's capabilities
1809 * set up before registering.
1810 * If function fails the device must be freed with input_free_device().
1811 * Once device has been successfully registered it can be unregistered
1812 * with input_unregister_device(); input_free_device() should not be
1813 * called in this case.
1814 */
1815int input_register_device(struct input_dev *dev)
1816{
1817 static atomic_t input_no = ATOMIC_INIT(0);
1818 struct input_handler *handler;
1819 const char *path;
1820 int error;
1821
1822 /* Every input device generates EV_SYN/SYN_REPORT events. */
1823 __set_bit(EV_SYN, dev->evbit);
1824
1825 /* KEY_RESERVED is not supposed to be transmitted to userspace. */
1826 __clear_bit(KEY_RESERVED, dev->keybit);
1827
1828 /* Make sure that bitmasks not mentioned in dev->evbit are clean. */
1829 input_cleanse_bitmasks(dev);
1830
1831 if (!dev->hint_events_per_packet)
1832 dev->hint_events_per_packet =
1833 input_estimate_events_per_packet(dev);
1834
1835 /*
1836 * If delay and period are pre-set by the driver, then autorepeating
1837 * is handled by the driver itself and we don't do it in input.c.
1838 */
1839 init_timer(&dev->timer);
1840 if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
1841 dev->timer.data = (long) dev;
1842 dev->timer.function = input_repeat_key;
1843 dev->rep[REP_DELAY] = 250;
1844 dev->rep[REP_PERIOD] = 33;
1845 }
1846
1847 if (!dev->getkeycode)
1848 dev->getkeycode = input_default_getkeycode;
1849
1850 if (!dev->setkeycode)
1851 dev->setkeycode = input_default_setkeycode;
1852
1853 dev_set_name(&dev->dev, "input%ld",
1854 (unsigned long) atomic_inc_return(&input_no) - 1);
1855
1856 error = device_add(&dev->dev);
1857 if (error)
1858 return error;
1859
1860 path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1861 pr_info("%s as %s\n",
1862 dev->name ? dev->name : "Unspecified device",
1863 path ? path : "N/A");
1864 kfree(path);
1865
1866 error = mutex_lock_interruptible(&input_mutex);
1867 if (error) {
1868 device_del(&dev->dev);
1869 return error;
1870 }
1871
1872 list_add_tail(&dev->node, &input_dev_list);
1873
1874 list_for_each_entry(handler, &input_handler_list, node)
1875 input_attach_handler(dev, handler);
1876
1877 input_wakeup_procfs_readers();
1878
1879 mutex_unlock(&input_mutex);
1880
1881 return 0;
1882}
1883EXPORT_SYMBOL(input_register_device);
1884
1885/**
1886 * input_unregister_device - unregister previously registered device
1887 * @dev: device to be unregistered
1888 *
1889 * This function unregisters an input device. Once device is unregistered
1890 * the caller should not try to access it as it may get freed at any moment.
1891 */
1892void input_unregister_device(struct input_dev *dev)
1893{
1894 struct input_handle *handle, *next;
1895
1896 input_disconnect_device(dev);
1897
1898 mutex_lock(&input_mutex);
1899
1900 list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
1901 handle->handler->disconnect(handle);
1902 WARN_ON(!list_empty(&dev->h_list));
1903
1904 del_timer_sync(&dev->timer);
1905 list_del_init(&dev->node);
1906
1907 input_wakeup_procfs_readers();
1908
1909 mutex_unlock(&input_mutex);
1910
1911 device_unregister(&dev->dev);
1912}
1913EXPORT_SYMBOL(input_unregister_device);
1914
1915/**
1916 * input_register_handler - register a new input handler
1917 * @handler: handler to be registered
1918 *
1919 * This function registers a new input handler (interface) for input
1920 * devices in the system and attaches it to all input devices that
1921 * are compatible with the handler.
1922 */
1923int input_register_handler(struct input_handler *handler)
1924{
1925 struct input_dev *dev;
1926 int retval;
1927
1928 retval = mutex_lock_interruptible(&input_mutex);
1929 if (retval)
1930 return retval;
1931
1932 INIT_LIST_HEAD(&handler->h_list);
1933
1934 if (handler->fops != NULL) {
1935 if (input_table[handler->minor >> 5]) {
1936 retval = -EBUSY;
1937 goto out;
1938 }
1939 input_table[handler->minor >> 5] = handler;
1940 }
1941
1942 list_add_tail(&handler->node, &input_handler_list);
1943
1944 list_for_each_entry(dev, &input_dev_list, node)
1945 input_attach_handler(dev, handler);
1946
1947 input_wakeup_procfs_readers();
1948
1949 out:
1950 mutex_unlock(&input_mutex);
1951 return retval;
1952}
1953EXPORT_SYMBOL(input_register_handler);
1954
1955/**
1956 * input_unregister_handler - unregisters an input handler
1957 * @handler: handler to be unregistered
1958 *
1959 * This function disconnects a handler from its input devices and
1960 * removes it from lists of known handlers.
1961 */
1962void input_unregister_handler(struct input_handler *handler)
1963{
1964 struct input_handle *handle, *next;
1965
1966 mutex_lock(&input_mutex);
1967
1968 list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
1969 handler->disconnect(handle);
1970 WARN_ON(!list_empty(&handler->h_list));
1971
1972 list_del_init(&handler->node);
1973
1974 if (handler->fops != NULL)
1975 input_table[handler->minor >> 5] = NULL;
1976
1977 input_wakeup_procfs_readers();
1978
1979 mutex_unlock(&input_mutex);
1980}
1981EXPORT_SYMBOL(input_unregister_handler);
1982
1983/**
1984 * input_handler_for_each_handle - handle iterator
1985 * @handler: input handler to iterate
1986 * @data: data for the callback
1987 * @fn: function to be called for each handle
1988 *
1989 * Iterate over @bus's list of devices, and call @fn for each, passing
1990 * it @data and stop when @fn returns a non-zero value. The function is
1991 * using RCU to traverse the list and therefore may be usind in atonic
1992 * contexts. The @fn callback is invoked from RCU critical section and
1993 * thus must not sleep.
1994 */
1995int input_handler_for_each_handle(struct input_handler *handler, void *data,
1996 int (*fn)(struct input_handle *, void *))
1997{
1998 struct input_handle *handle;
1999 int retval = 0;
2000
2001 rcu_read_lock();
2002
2003 list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
2004 retval = fn(handle, data);
2005 if (retval)
2006 break;
2007 }
2008
2009 rcu_read_unlock();
2010
2011 return retval;
2012}
2013EXPORT_SYMBOL(input_handler_for_each_handle);
2014
2015/**
2016 * input_register_handle - register a new input handle
2017 * @handle: handle to register
2018 *
2019 * This function puts a new input handle onto device's
2020 * and handler's lists so that events can flow through
2021 * it once it is opened using input_open_device().
2022 *
2023 * This function is supposed to be called from handler's
2024 * connect() method.
2025 */
2026int input_register_handle(struct input_handle *handle)
2027{
2028 struct input_handler *handler = handle->handler;
2029 struct input_dev *dev = handle->dev;
2030 int error;
2031
2032 /*
2033 * We take dev->mutex here to prevent race with
2034 * input_release_device().
2035 */
2036 error = mutex_lock_interruptible(&dev->mutex);
2037 if (error)
2038 return error;
2039
2040 /*
2041 * Filters go to the head of the list, normal handlers
2042 * to the tail.
2043 */
2044 if (handler->filter)
2045 list_add_rcu(&handle->d_node, &dev->h_list);
2046 else
2047 list_add_tail_rcu(&handle->d_node, &dev->h_list);
2048
2049 mutex_unlock(&dev->mutex);
2050
2051 /*
2052 * Since we are supposed to be called from ->connect()
2053 * which is mutually exclusive with ->disconnect()
2054 * we can't be racing with input_unregister_handle()
2055 * and so separate lock is not needed here.
2056 */
2057 list_add_tail_rcu(&handle->h_node, &handler->h_list);
2058
2059 if (handler->start)
2060 handler->start(handle);
2061
2062 return 0;
2063}
2064EXPORT_SYMBOL(input_register_handle);
2065
2066/**
2067 * input_unregister_handle - unregister an input handle
2068 * @handle: handle to unregister
2069 *
2070 * This function removes input handle from device's
2071 * and handler's lists.
2072 *
2073 * This function is supposed to be called from handler's
2074 * disconnect() method.
2075 */
2076void input_unregister_handle(struct input_handle *handle)
2077{
2078 struct input_dev *dev = handle->dev;
2079
2080 list_del_rcu(&handle->h_node);
2081
2082 /*
2083 * Take dev->mutex to prevent race with input_release_device().
2084 */
2085 mutex_lock(&dev->mutex);
2086 list_del_rcu(&handle->d_node);
2087 mutex_unlock(&dev->mutex);
2088
2089 synchronize_rcu();
2090}
2091EXPORT_SYMBOL(input_unregister_handle);
2092
2093static int input_open_file(struct inode *inode, struct file *file)
2094{
2095 struct input_handler *handler;
2096 const struct file_operations *old_fops, *new_fops = NULL;
2097 int err;
2098
2099 err = mutex_lock_interruptible(&input_mutex);
2100 if (err)
2101 return err;
2102
2103 /* No load-on-demand here? */
2104 handler = input_table[iminor(inode) >> 5];
2105 if (handler)
2106 new_fops = fops_get(handler->fops);
2107
2108 mutex_unlock(&input_mutex);
2109
2110 /*
2111 * That's _really_ odd. Usually NULL ->open means "nothing special",
2112 * not "no device". Oh, well...
2113 */
2114 if (!new_fops || !new_fops->open) {
2115 fops_put(new_fops);
2116 err = -ENODEV;
2117 goto out;
2118 }
2119
2120 old_fops = file->f_op;
2121 file->f_op = new_fops;
2122
2123 err = new_fops->open(inode, file);
2124 if (err) {
2125 fops_put(file->f_op);
2126 file->f_op = fops_get(old_fops);
2127 }
2128 fops_put(old_fops);
2129out:
2130 return err;
2131}
2132
2133static const struct file_operations input_fops = {
2134 .owner = THIS_MODULE,
2135 .open = input_open_file,
2136 .llseek = noop_llseek,
2137};
2138
2139static int __init input_init(void)
2140{
2141 int err;
2142
2143 err = class_register(&input_class);
2144 if (err) {
2145 pr_err("unable to register input_dev class\n");
2146 return err;
2147 }
2148
2149 err = input_proc_init();
2150 if (err)
2151 goto fail1;
2152
2153 err = register_chrdev(INPUT_MAJOR, "input", &input_fops);
2154 if (err) {
2155 pr_err("unable to register char major %d", INPUT_MAJOR);
2156 goto fail2;
2157 }
2158
2159 return 0;
2160
2161 fail2: input_proc_exit();
2162 fail1: class_unregister(&input_class);
2163 return err;
2164}
2165
2166static void __exit input_exit(void)
2167{
2168 input_proc_exit();
2169 unregister_chrdev(INPUT_MAJOR, "input");
2170 class_unregister(&input_class);
2171}
2172
2173subsys_initcall(input_init);
2174module_exit(input_exit);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * The input core
4 *
5 * Copyright (c) 1999-2002 Vojtech Pavlik
6 */
7
8
9#define pr_fmt(fmt) KBUILD_BASENAME ": " fmt
10
11#include <linux/init.h>
12#include <linux/types.h>
13#include <linux/idr.h>
14#include <linux/input/mt.h>
15#include <linux/module.h>
16#include <linux/slab.h>
17#include <linux/random.h>
18#include <linux/major.h>
19#include <linux/proc_fs.h>
20#include <linux/sched.h>
21#include <linux/seq_file.h>
22#include <linux/pm.h>
23#include <linux/poll.h>
24#include <linux/device.h>
25#include <linux/kstrtox.h>
26#include <linux/mutex.h>
27#include <linux/rcupdate.h>
28#include "input-compat.h"
29#include "input-core-private.h"
30#include "input-poller.h"
31
32MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
33MODULE_DESCRIPTION("Input core");
34MODULE_LICENSE("GPL");
35
36#define INPUT_MAX_CHAR_DEVICES 1024
37#define INPUT_FIRST_DYNAMIC_DEV 256
38static DEFINE_IDA(input_ida);
39
40static LIST_HEAD(input_dev_list);
41static 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 */
49static DEFINE_MUTEX(input_mutex);
50
51static const struct input_value input_value_sync = { EV_SYN, SYN_REPORT, 1 };
52
53static const unsigned int input_max_code[EV_CNT] = {
54 [EV_KEY] = KEY_MAX,
55 [EV_REL] = REL_MAX,
56 [EV_ABS] = ABS_MAX,
57 [EV_MSC] = MSC_MAX,
58 [EV_SW] = SW_MAX,
59 [EV_LED] = LED_MAX,
60 [EV_SND] = SND_MAX,
61 [EV_FF] = FF_MAX,
62};
63
64static inline int is_event_supported(unsigned int code,
65 unsigned long *bm, unsigned int max)
66{
67 return code <= max && test_bit(code, bm);
68}
69
70static int input_defuzz_abs_event(int value, int old_val, int fuzz)
71{
72 if (fuzz) {
73 if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
74 return old_val;
75
76 if (value > old_val - fuzz && value < old_val + fuzz)
77 return (old_val * 3 + value) / 4;
78
79 if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
80 return (old_val + value) / 2;
81 }
82
83 return value;
84}
85
86static void input_start_autorepeat(struct input_dev *dev, int code)
87{
88 if (test_bit(EV_REP, dev->evbit) &&
89 dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
90 dev->timer.function) {
91 dev->repeat_key = code;
92 mod_timer(&dev->timer,
93 jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
94 }
95}
96
97static void input_stop_autorepeat(struct input_dev *dev)
98{
99 del_timer(&dev->timer);
100}
101
102/*
103 * Pass values first through all filters and then, if event has not been
104 * filtered out, through all open handles. This order is achieved by placing
105 * filters at the head of the list of handles attached to the device, and
106 * placing regular handles at the tail of the list.
107 *
108 * This function is called with dev->event_lock held and interrupts disabled.
109 */
110static void input_pass_values(struct input_dev *dev,
111 struct input_value *vals, unsigned int count)
112{
113 struct input_handle *handle;
114 struct input_value *v;
115
116 lockdep_assert_held(&dev->event_lock);
117
118 rcu_read_lock();
119
120 handle = rcu_dereference(dev->grab);
121 if (handle) {
122 count = handle->handle_events(handle, vals, count);
123 } else {
124 list_for_each_entry_rcu(handle, &dev->h_list, d_node)
125 if (handle->open) {
126 count = handle->handle_events(handle, vals,
127 count);
128 if (!count)
129 break;
130 }
131 }
132
133 rcu_read_unlock();
134
135 /* trigger auto repeat for key events */
136 if (test_bit(EV_REP, dev->evbit) && test_bit(EV_KEY, dev->evbit)) {
137 for (v = vals; v != vals + count; v++) {
138 if (v->type == EV_KEY && v->value != 2) {
139 if (v->value)
140 input_start_autorepeat(dev, v->code);
141 else
142 input_stop_autorepeat(dev);
143 }
144 }
145 }
146}
147
148#define INPUT_IGNORE_EVENT 0
149#define INPUT_PASS_TO_HANDLERS 1
150#define INPUT_PASS_TO_DEVICE 2
151#define INPUT_SLOT 4
152#define INPUT_FLUSH 8
153#define INPUT_PASS_TO_ALL (INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
154
155static int input_handle_abs_event(struct input_dev *dev,
156 unsigned int code, int *pval)
157{
158 struct input_mt *mt = dev->mt;
159 bool is_new_slot = false;
160 bool is_mt_event;
161 int *pold;
162
163 if (code == ABS_MT_SLOT) {
164 /*
165 * "Stage" the event; we'll flush it later, when we
166 * get actual touch data.
167 */
168 if (mt && *pval >= 0 && *pval < mt->num_slots)
169 mt->slot = *pval;
170
171 return INPUT_IGNORE_EVENT;
172 }
173
174 is_mt_event = input_is_mt_value(code);
175
176 if (!is_mt_event) {
177 pold = &dev->absinfo[code].value;
178 } else if (mt) {
179 pold = &mt->slots[mt->slot].abs[code - ABS_MT_FIRST];
180 is_new_slot = mt->slot != dev->absinfo[ABS_MT_SLOT].value;
181 } else {
182 /*
183 * Bypass filtering for multi-touch events when
184 * not employing slots.
185 */
186 pold = NULL;
187 }
188
189 if (pold) {
190 *pval = input_defuzz_abs_event(*pval, *pold,
191 dev->absinfo[code].fuzz);
192 if (*pold == *pval)
193 return INPUT_IGNORE_EVENT;
194
195 *pold = *pval;
196 }
197
198 /* Flush pending "slot" event */
199 if (is_new_slot) {
200 dev->absinfo[ABS_MT_SLOT].value = mt->slot;
201 return INPUT_PASS_TO_HANDLERS | INPUT_SLOT;
202 }
203
204 return INPUT_PASS_TO_HANDLERS;
205}
206
207static int input_get_disposition(struct input_dev *dev,
208 unsigned int type, unsigned int code, int *pval)
209{
210 int disposition = INPUT_IGNORE_EVENT;
211 int value = *pval;
212
213 /* filter-out events from inhibited devices */
214 if (dev->inhibited)
215 return INPUT_IGNORE_EVENT;
216
217 switch (type) {
218
219 case EV_SYN:
220 switch (code) {
221 case SYN_CONFIG:
222 disposition = INPUT_PASS_TO_ALL;
223 break;
224
225 case SYN_REPORT:
226 disposition = INPUT_PASS_TO_HANDLERS | INPUT_FLUSH;
227 break;
228 case SYN_MT_REPORT:
229 disposition = INPUT_PASS_TO_HANDLERS;
230 break;
231 }
232 break;
233
234 case EV_KEY:
235 if (is_event_supported(code, dev->keybit, KEY_MAX)) {
236
237 /* auto-repeat bypasses state updates */
238 if (value == 2) {
239 disposition = INPUT_PASS_TO_HANDLERS;
240 break;
241 }
242
243 if (!!test_bit(code, dev->key) != !!value) {
244
245 __change_bit(code, dev->key);
246 disposition = INPUT_PASS_TO_HANDLERS;
247 }
248 }
249 break;
250
251 case EV_SW:
252 if (is_event_supported(code, dev->swbit, SW_MAX) &&
253 !!test_bit(code, dev->sw) != !!value) {
254
255 __change_bit(code, dev->sw);
256 disposition = INPUT_PASS_TO_HANDLERS;
257 }
258 break;
259
260 case EV_ABS:
261 if (is_event_supported(code, dev->absbit, ABS_MAX))
262 disposition = input_handle_abs_event(dev, code, &value);
263
264 break;
265
266 case EV_REL:
267 if (is_event_supported(code, dev->relbit, REL_MAX) && value)
268 disposition = INPUT_PASS_TO_HANDLERS;
269
270 break;
271
272 case EV_MSC:
273 if (is_event_supported(code, dev->mscbit, MSC_MAX))
274 disposition = INPUT_PASS_TO_ALL;
275
276 break;
277
278 case EV_LED:
279 if (is_event_supported(code, dev->ledbit, LED_MAX) &&
280 !!test_bit(code, dev->led) != !!value) {
281
282 __change_bit(code, dev->led);
283 disposition = INPUT_PASS_TO_ALL;
284 }
285 break;
286
287 case EV_SND:
288 if (is_event_supported(code, dev->sndbit, SND_MAX)) {
289
290 if (!!test_bit(code, dev->snd) != !!value)
291 __change_bit(code, dev->snd);
292 disposition = INPUT_PASS_TO_ALL;
293 }
294 break;
295
296 case EV_REP:
297 if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
298 dev->rep[code] = value;
299 disposition = INPUT_PASS_TO_ALL;
300 }
301 break;
302
303 case EV_FF:
304 if (value >= 0)
305 disposition = INPUT_PASS_TO_ALL;
306 break;
307
308 case EV_PWR:
309 disposition = INPUT_PASS_TO_ALL;
310 break;
311 }
312
313 *pval = value;
314 return disposition;
315}
316
317static void input_event_dispose(struct input_dev *dev, int disposition,
318 unsigned int type, unsigned int code, int value)
319{
320 if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
321 dev->event(dev, type, code, value);
322
323 if (disposition & INPUT_PASS_TO_HANDLERS) {
324 struct input_value *v;
325
326 if (disposition & INPUT_SLOT) {
327 v = &dev->vals[dev->num_vals++];
328 v->type = EV_ABS;
329 v->code = ABS_MT_SLOT;
330 v->value = dev->mt->slot;
331 }
332
333 v = &dev->vals[dev->num_vals++];
334 v->type = type;
335 v->code = code;
336 v->value = value;
337 }
338
339 if (disposition & INPUT_FLUSH) {
340 if (dev->num_vals >= 2)
341 input_pass_values(dev, dev->vals, dev->num_vals);
342 dev->num_vals = 0;
343 /*
344 * Reset the timestamp on flush so we won't end up
345 * with a stale one. Note we only need to reset the
346 * monolithic one as we use its presence when deciding
347 * whether to generate a synthetic timestamp.
348 */
349 dev->timestamp[INPUT_CLK_MONO] = ktime_set(0, 0);
350 } else if (dev->num_vals >= dev->max_vals - 2) {
351 dev->vals[dev->num_vals++] = input_value_sync;
352 input_pass_values(dev, dev->vals, dev->num_vals);
353 dev->num_vals = 0;
354 }
355}
356
357void input_handle_event(struct input_dev *dev,
358 unsigned int type, unsigned int code, int value)
359{
360 int disposition;
361
362 lockdep_assert_held(&dev->event_lock);
363
364 disposition = input_get_disposition(dev, type, code, &value);
365 if (disposition != INPUT_IGNORE_EVENT) {
366 if (type != EV_SYN)
367 add_input_randomness(type, code, value);
368
369 input_event_dispose(dev, disposition, type, code, value);
370 }
371}
372
373/**
374 * input_event() - report new input event
375 * @dev: device that generated the event
376 * @type: type of the event
377 * @code: event code
378 * @value: value of the event
379 *
380 * This function should be used by drivers implementing various input
381 * devices to report input events. See also input_inject_event().
382 *
383 * NOTE: input_event() may be safely used right after input device was
384 * allocated with input_allocate_device(), even before it is registered
385 * with input_register_device(), but the event will not reach any of the
386 * input handlers. Such early invocation of input_event() may be used
387 * to 'seed' initial state of a switch or initial position of absolute
388 * axis, etc.
389 */
390void input_event(struct input_dev *dev,
391 unsigned int type, unsigned int code, int value)
392{
393 unsigned long flags;
394
395 if (is_event_supported(type, dev->evbit, EV_MAX)) {
396
397 spin_lock_irqsave(&dev->event_lock, flags);
398 input_handle_event(dev, type, code, value);
399 spin_unlock_irqrestore(&dev->event_lock, flags);
400 }
401}
402EXPORT_SYMBOL(input_event);
403
404/**
405 * input_inject_event() - send input event from input handler
406 * @handle: input handle to send event through
407 * @type: type of the event
408 * @code: event code
409 * @value: value of the event
410 *
411 * Similar to input_event() but will ignore event if device is
412 * "grabbed" and handle injecting event is not the one that owns
413 * the device.
414 */
415void input_inject_event(struct input_handle *handle,
416 unsigned int type, unsigned int code, int value)
417{
418 struct input_dev *dev = handle->dev;
419 struct input_handle *grab;
420 unsigned long flags;
421
422 if (is_event_supported(type, dev->evbit, EV_MAX)) {
423 spin_lock_irqsave(&dev->event_lock, flags);
424
425 rcu_read_lock();
426 grab = rcu_dereference(dev->grab);
427 if (!grab || grab == handle)
428 input_handle_event(dev, type, code, value);
429 rcu_read_unlock();
430
431 spin_unlock_irqrestore(&dev->event_lock, flags);
432 }
433}
434EXPORT_SYMBOL(input_inject_event);
435
436/**
437 * input_alloc_absinfo - allocates array of input_absinfo structs
438 * @dev: the input device emitting absolute events
439 *
440 * If the absinfo struct the caller asked for is already allocated, this
441 * functions will not do anything.
442 */
443void input_alloc_absinfo(struct input_dev *dev)
444{
445 if (dev->absinfo)
446 return;
447
448 dev->absinfo = kcalloc(ABS_CNT, sizeof(*dev->absinfo), GFP_KERNEL);
449 if (!dev->absinfo) {
450 dev_err(dev->dev.parent ?: &dev->dev,
451 "%s: unable to allocate memory\n", __func__);
452 /*
453 * We will handle this allocation failure in
454 * input_register_device() when we refuse to register input
455 * device with ABS bits but without absinfo.
456 */
457 }
458}
459EXPORT_SYMBOL(input_alloc_absinfo);
460
461void input_set_abs_params(struct input_dev *dev, unsigned int axis,
462 int min, int max, int fuzz, int flat)
463{
464 struct input_absinfo *absinfo;
465
466 __set_bit(EV_ABS, dev->evbit);
467 __set_bit(axis, dev->absbit);
468
469 input_alloc_absinfo(dev);
470 if (!dev->absinfo)
471 return;
472
473 absinfo = &dev->absinfo[axis];
474 absinfo->minimum = min;
475 absinfo->maximum = max;
476 absinfo->fuzz = fuzz;
477 absinfo->flat = flat;
478}
479EXPORT_SYMBOL(input_set_abs_params);
480
481/**
482 * input_copy_abs - Copy absinfo from one input_dev to another
483 * @dst: Destination input device to copy the abs settings to
484 * @dst_axis: ABS_* value selecting the destination axis
485 * @src: Source input device to copy the abs settings from
486 * @src_axis: ABS_* value selecting the source axis
487 *
488 * Set absinfo for the selected destination axis by copying it from
489 * the specified source input device's source axis.
490 * This is useful to e.g. setup a pen/stylus input-device for combined
491 * touchscreen/pen hardware where the pen uses the same coordinates as
492 * the touchscreen.
493 */
494void input_copy_abs(struct input_dev *dst, unsigned int dst_axis,
495 const struct input_dev *src, unsigned int src_axis)
496{
497 /* src must have EV_ABS and src_axis set */
498 if (WARN_ON(!(test_bit(EV_ABS, src->evbit) &&
499 test_bit(src_axis, src->absbit))))
500 return;
501
502 /*
503 * input_alloc_absinfo() may have failed for the source. Our caller is
504 * expected to catch this when registering the input devices, which may
505 * happen after the input_copy_abs() call.
506 */
507 if (!src->absinfo)
508 return;
509
510 input_set_capability(dst, EV_ABS, dst_axis);
511 if (!dst->absinfo)
512 return;
513
514 dst->absinfo[dst_axis] = src->absinfo[src_axis];
515}
516EXPORT_SYMBOL(input_copy_abs);
517
518/**
519 * input_grab_device - grabs device for exclusive use
520 * @handle: input handle that wants to own the device
521 *
522 * When a device is grabbed by an input handle all events generated by
523 * the device are delivered only to this handle. Also events injected
524 * by other input handles are ignored while device is grabbed.
525 */
526int input_grab_device(struct input_handle *handle)
527{
528 struct input_dev *dev = handle->dev;
529 int retval;
530
531 retval = mutex_lock_interruptible(&dev->mutex);
532 if (retval)
533 return retval;
534
535 if (dev->grab) {
536 retval = -EBUSY;
537 goto out;
538 }
539
540 rcu_assign_pointer(dev->grab, handle);
541
542 out:
543 mutex_unlock(&dev->mutex);
544 return retval;
545}
546EXPORT_SYMBOL(input_grab_device);
547
548static void __input_release_device(struct input_handle *handle)
549{
550 struct input_dev *dev = handle->dev;
551 struct input_handle *grabber;
552
553 grabber = rcu_dereference_protected(dev->grab,
554 lockdep_is_held(&dev->mutex));
555 if (grabber == handle) {
556 rcu_assign_pointer(dev->grab, NULL);
557 /* Make sure input_pass_values() notices that grab is gone */
558 synchronize_rcu();
559
560 list_for_each_entry(handle, &dev->h_list, d_node)
561 if (handle->open && handle->handler->start)
562 handle->handler->start(handle);
563 }
564}
565
566/**
567 * input_release_device - release previously grabbed device
568 * @handle: input handle that owns the device
569 *
570 * Releases previously grabbed device so that other input handles can
571 * start receiving input events. Upon release all handlers attached
572 * to the device have their start() method called so they have a change
573 * to synchronize device state with the rest of the system.
574 */
575void input_release_device(struct input_handle *handle)
576{
577 struct input_dev *dev = handle->dev;
578
579 mutex_lock(&dev->mutex);
580 __input_release_device(handle);
581 mutex_unlock(&dev->mutex);
582}
583EXPORT_SYMBOL(input_release_device);
584
585/**
586 * input_open_device - open input device
587 * @handle: handle through which device is being accessed
588 *
589 * This function should be called by input handlers when they
590 * want to start receive events from given input device.
591 */
592int input_open_device(struct input_handle *handle)
593{
594 struct input_dev *dev = handle->dev;
595 int retval;
596
597 retval = mutex_lock_interruptible(&dev->mutex);
598 if (retval)
599 return retval;
600
601 if (dev->going_away) {
602 retval = -ENODEV;
603 goto out;
604 }
605
606 handle->open++;
607
608 if (handle->handler->passive_observer)
609 goto out;
610
611 if (dev->users++ || dev->inhibited) {
612 /*
613 * Device is already opened and/or inhibited,
614 * so we can exit immediately and report success.
615 */
616 goto out;
617 }
618
619 if (dev->open) {
620 retval = dev->open(dev);
621 if (retval) {
622 dev->users--;
623 handle->open--;
624 /*
625 * Make sure we are not delivering any more events
626 * through this handle
627 */
628 synchronize_rcu();
629 goto out;
630 }
631 }
632
633 if (dev->poller)
634 input_dev_poller_start(dev->poller);
635
636 out:
637 mutex_unlock(&dev->mutex);
638 return retval;
639}
640EXPORT_SYMBOL(input_open_device);
641
642int input_flush_device(struct input_handle *handle, struct file *file)
643{
644 struct input_dev *dev = handle->dev;
645 int retval;
646
647 retval = mutex_lock_interruptible(&dev->mutex);
648 if (retval)
649 return retval;
650
651 if (dev->flush)
652 retval = dev->flush(dev, file);
653
654 mutex_unlock(&dev->mutex);
655 return retval;
656}
657EXPORT_SYMBOL(input_flush_device);
658
659/**
660 * input_close_device - close input device
661 * @handle: handle through which device is being accessed
662 *
663 * This function should be called by input handlers when they
664 * want to stop receive events from given input device.
665 */
666void input_close_device(struct input_handle *handle)
667{
668 struct input_dev *dev = handle->dev;
669
670 mutex_lock(&dev->mutex);
671
672 __input_release_device(handle);
673
674 if (!handle->handler->passive_observer) {
675 if (!--dev->users && !dev->inhibited) {
676 if (dev->poller)
677 input_dev_poller_stop(dev->poller);
678 if (dev->close)
679 dev->close(dev);
680 }
681 }
682
683 if (!--handle->open) {
684 /*
685 * synchronize_rcu() makes sure that input_pass_values()
686 * completed and that no more input events are delivered
687 * through this handle
688 */
689 synchronize_rcu();
690 }
691
692 mutex_unlock(&dev->mutex);
693}
694EXPORT_SYMBOL(input_close_device);
695
696/*
697 * Simulate keyup events for all keys that are marked as pressed.
698 * The function must be called with dev->event_lock held.
699 */
700static bool input_dev_release_keys(struct input_dev *dev)
701{
702 bool need_sync = false;
703 int code;
704
705 lockdep_assert_held(&dev->event_lock);
706
707 if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
708 for_each_set_bit(code, dev->key, KEY_CNT) {
709 input_handle_event(dev, EV_KEY, code, 0);
710 need_sync = true;
711 }
712 }
713
714 return need_sync;
715}
716
717/*
718 * Prepare device for unregistering
719 */
720static void input_disconnect_device(struct input_dev *dev)
721{
722 struct input_handle *handle;
723
724 /*
725 * Mark device as going away. Note that we take dev->mutex here
726 * not to protect access to dev->going_away but rather to ensure
727 * that there are no threads in the middle of input_open_device()
728 */
729 mutex_lock(&dev->mutex);
730 dev->going_away = true;
731 mutex_unlock(&dev->mutex);
732
733 spin_lock_irq(&dev->event_lock);
734
735 /*
736 * Simulate keyup events for all pressed keys so that handlers
737 * are not left with "stuck" keys. The driver may continue
738 * generate events even after we done here but they will not
739 * reach any handlers.
740 */
741 if (input_dev_release_keys(dev))
742 input_handle_event(dev, EV_SYN, SYN_REPORT, 1);
743
744 list_for_each_entry(handle, &dev->h_list, d_node)
745 handle->open = 0;
746
747 spin_unlock_irq(&dev->event_lock);
748}
749
750/**
751 * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
752 * @ke: keymap entry containing scancode to be converted.
753 * @scancode: pointer to the location where converted scancode should
754 * be stored.
755 *
756 * This function is used to convert scancode stored in &struct keymap_entry
757 * into scalar form understood by legacy keymap handling methods. These
758 * methods expect scancodes to be represented as 'unsigned int'.
759 */
760int input_scancode_to_scalar(const struct input_keymap_entry *ke,
761 unsigned int *scancode)
762{
763 switch (ke->len) {
764 case 1:
765 *scancode = *((u8 *)ke->scancode);
766 break;
767
768 case 2:
769 *scancode = *((u16 *)ke->scancode);
770 break;
771
772 case 4:
773 *scancode = *((u32 *)ke->scancode);
774 break;
775
776 default:
777 return -EINVAL;
778 }
779
780 return 0;
781}
782EXPORT_SYMBOL(input_scancode_to_scalar);
783
784/*
785 * Those routines handle the default case where no [gs]etkeycode() is
786 * defined. In this case, an array indexed by the scancode is used.
787 */
788
789static unsigned int input_fetch_keycode(struct input_dev *dev,
790 unsigned int index)
791{
792 switch (dev->keycodesize) {
793 case 1:
794 return ((u8 *)dev->keycode)[index];
795
796 case 2:
797 return ((u16 *)dev->keycode)[index];
798
799 default:
800 return ((u32 *)dev->keycode)[index];
801 }
802}
803
804static int input_default_getkeycode(struct input_dev *dev,
805 struct input_keymap_entry *ke)
806{
807 unsigned int index;
808 int error;
809
810 if (!dev->keycodesize)
811 return -EINVAL;
812
813 if (ke->flags & INPUT_KEYMAP_BY_INDEX)
814 index = ke->index;
815 else {
816 error = input_scancode_to_scalar(ke, &index);
817 if (error)
818 return error;
819 }
820
821 if (index >= dev->keycodemax)
822 return -EINVAL;
823
824 ke->keycode = input_fetch_keycode(dev, index);
825 ke->index = index;
826 ke->len = sizeof(index);
827 memcpy(ke->scancode, &index, sizeof(index));
828
829 return 0;
830}
831
832static int input_default_setkeycode(struct input_dev *dev,
833 const struct input_keymap_entry *ke,
834 unsigned int *old_keycode)
835{
836 unsigned int index;
837 int error;
838 int i;
839
840 if (!dev->keycodesize)
841 return -EINVAL;
842
843 if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
844 index = ke->index;
845 } else {
846 error = input_scancode_to_scalar(ke, &index);
847 if (error)
848 return error;
849 }
850
851 if (index >= dev->keycodemax)
852 return -EINVAL;
853
854 if (dev->keycodesize < sizeof(ke->keycode) &&
855 (ke->keycode >> (dev->keycodesize * 8)))
856 return -EINVAL;
857
858 switch (dev->keycodesize) {
859 case 1: {
860 u8 *k = (u8 *)dev->keycode;
861 *old_keycode = k[index];
862 k[index] = ke->keycode;
863 break;
864 }
865 case 2: {
866 u16 *k = (u16 *)dev->keycode;
867 *old_keycode = k[index];
868 k[index] = ke->keycode;
869 break;
870 }
871 default: {
872 u32 *k = (u32 *)dev->keycode;
873 *old_keycode = k[index];
874 k[index] = ke->keycode;
875 break;
876 }
877 }
878
879 if (*old_keycode <= KEY_MAX) {
880 __clear_bit(*old_keycode, dev->keybit);
881 for (i = 0; i < dev->keycodemax; i++) {
882 if (input_fetch_keycode(dev, i) == *old_keycode) {
883 __set_bit(*old_keycode, dev->keybit);
884 /* Setting the bit twice is useless, so break */
885 break;
886 }
887 }
888 }
889
890 __set_bit(ke->keycode, dev->keybit);
891 return 0;
892}
893
894/**
895 * input_get_keycode - retrieve keycode currently mapped to a given scancode
896 * @dev: input device which keymap is being queried
897 * @ke: keymap entry
898 *
899 * This function should be called by anyone interested in retrieving current
900 * keymap. Presently evdev handlers use it.
901 */
902int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
903{
904 unsigned long flags;
905 int retval;
906
907 spin_lock_irqsave(&dev->event_lock, flags);
908 retval = dev->getkeycode(dev, ke);
909 spin_unlock_irqrestore(&dev->event_lock, flags);
910
911 return retval;
912}
913EXPORT_SYMBOL(input_get_keycode);
914
915/**
916 * input_set_keycode - attribute a keycode to a given scancode
917 * @dev: input device which keymap is being updated
918 * @ke: new keymap entry
919 *
920 * This function should be called by anyone needing to update current
921 * keymap. Presently keyboard and evdev handlers use it.
922 */
923int input_set_keycode(struct input_dev *dev,
924 const struct input_keymap_entry *ke)
925{
926 unsigned long flags;
927 unsigned int old_keycode;
928 int retval;
929
930 if (ke->keycode > KEY_MAX)
931 return -EINVAL;
932
933 spin_lock_irqsave(&dev->event_lock, flags);
934
935 retval = dev->setkeycode(dev, ke, &old_keycode);
936 if (retval)
937 goto out;
938
939 /* Make sure KEY_RESERVED did not get enabled. */
940 __clear_bit(KEY_RESERVED, dev->keybit);
941
942 /*
943 * Simulate keyup event if keycode is not present
944 * in the keymap anymore
945 */
946 if (old_keycode > KEY_MAX) {
947 dev_warn(dev->dev.parent ?: &dev->dev,
948 "%s: got too big old keycode %#x\n",
949 __func__, old_keycode);
950 } else if (test_bit(EV_KEY, dev->evbit) &&
951 !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
952 __test_and_clear_bit(old_keycode, dev->key)) {
953 /*
954 * We have to use input_event_dispose() here directly instead
955 * of input_handle_event() because the key we want to release
956 * here is considered no longer supported by the device and
957 * input_handle_event() will ignore it.
958 */
959 input_event_dispose(dev, INPUT_PASS_TO_HANDLERS,
960 EV_KEY, old_keycode, 0);
961 input_event_dispose(dev, INPUT_PASS_TO_HANDLERS | INPUT_FLUSH,
962 EV_SYN, SYN_REPORT, 1);
963 }
964
965 out:
966 spin_unlock_irqrestore(&dev->event_lock, flags);
967
968 return retval;
969}
970EXPORT_SYMBOL(input_set_keycode);
971
972bool input_match_device_id(const struct input_dev *dev,
973 const struct input_device_id *id)
974{
975 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
976 if (id->bustype != dev->id.bustype)
977 return false;
978
979 if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
980 if (id->vendor != dev->id.vendor)
981 return false;
982
983 if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
984 if (id->product != dev->id.product)
985 return false;
986
987 if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
988 if (id->version != dev->id.version)
989 return false;
990
991 if (!bitmap_subset(id->evbit, dev->evbit, EV_MAX) ||
992 !bitmap_subset(id->keybit, dev->keybit, KEY_MAX) ||
993 !bitmap_subset(id->relbit, dev->relbit, REL_MAX) ||
994 !bitmap_subset(id->absbit, dev->absbit, ABS_MAX) ||
995 !bitmap_subset(id->mscbit, dev->mscbit, MSC_MAX) ||
996 !bitmap_subset(id->ledbit, dev->ledbit, LED_MAX) ||
997 !bitmap_subset(id->sndbit, dev->sndbit, SND_MAX) ||
998 !bitmap_subset(id->ffbit, dev->ffbit, FF_MAX) ||
999 !bitmap_subset(id->swbit, dev->swbit, SW_MAX) ||
1000 !bitmap_subset(id->propbit, dev->propbit, INPUT_PROP_MAX)) {
1001 return false;
1002 }
1003
1004 return true;
1005}
1006EXPORT_SYMBOL(input_match_device_id);
1007
1008static const struct input_device_id *input_match_device(struct input_handler *handler,
1009 struct input_dev *dev)
1010{
1011 const struct input_device_id *id;
1012
1013 for (id = handler->id_table; id->flags || id->driver_info; id++) {
1014 if (input_match_device_id(dev, id) &&
1015 (!handler->match || handler->match(handler, dev))) {
1016 return id;
1017 }
1018 }
1019
1020 return NULL;
1021}
1022
1023static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
1024{
1025 const struct input_device_id *id;
1026 int error;
1027
1028 id = input_match_device(handler, dev);
1029 if (!id)
1030 return -ENODEV;
1031
1032 error = handler->connect(handler, dev, id);
1033 if (error && error != -ENODEV)
1034 pr_err("failed to attach handler %s to device %s, error: %d\n",
1035 handler->name, kobject_name(&dev->dev.kobj), error);
1036
1037 return error;
1038}
1039
1040#ifdef CONFIG_COMPAT
1041
1042static int input_bits_to_string(char *buf, int buf_size,
1043 unsigned long bits, bool skip_empty)
1044{
1045 int len = 0;
1046
1047 if (in_compat_syscall()) {
1048 u32 dword = bits >> 32;
1049 if (dword || !skip_empty)
1050 len += snprintf(buf, buf_size, "%x ", dword);
1051
1052 dword = bits & 0xffffffffUL;
1053 if (dword || !skip_empty || len)
1054 len += snprintf(buf + len, max(buf_size - len, 0),
1055 "%x", dword);
1056 } else {
1057 if (bits || !skip_empty)
1058 len += snprintf(buf, buf_size, "%lx", bits);
1059 }
1060
1061 return len;
1062}
1063
1064#else /* !CONFIG_COMPAT */
1065
1066static int input_bits_to_string(char *buf, int buf_size,
1067 unsigned long bits, bool skip_empty)
1068{
1069 return bits || !skip_empty ?
1070 snprintf(buf, buf_size, "%lx", bits) : 0;
1071}
1072
1073#endif
1074
1075#ifdef CONFIG_PROC_FS
1076
1077static struct proc_dir_entry *proc_bus_input_dir;
1078static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
1079static int input_devices_state;
1080
1081static inline void input_wakeup_procfs_readers(void)
1082{
1083 input_devices_state++;
1084 wake_up(&input_devices_poll_wait);
1085}
1086
1087struct input_seq_state {
1088 unsigned short pos;
1089 bool mutex_acquired;
1090 int input_devices_state;
1091};
1092
1093static __poll_t input_proc_devices_poll(struct file *file, poll_table *wait)
1094{
1095 struct seq_file *seq = file->private_data;
1096 struct input_seq_state *state = seq->private;
1097
1098 poll_wait(file, &input_devices_poll_wait, wait);
1099 if (state->input_devices_state != input_devices_state) {
1100 state->input_devices_state = input_devices_state;
1101 return EPOLLIN | EPOLLRDNORM;
1102 }
1103
1104 return 0;
1105}
1106
1107static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
1108{
1109 struct input_seq_state *state = seq->private;
1110 int error;
1111
1112 error = mutex_lock_interruptible(&input_mutex);
1113 if (error) {
1114 state->mutex_acquired = false;
1115 return ERR_PTR(error);
1116 }
1117
1118 state->mutex_acquired = true;
1119
1120 return seq_list_start(&input_dev_list, *pos);
1121}
1122
1123static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1124{
1125 return seq_list_next(v, &input_dev_list, pos);
1126}
1127
1128static void input_seq_stop(struct seq_file *seq, void *v)
1129{
1130 struct input_seq_state *state = seq->private;
1131
1132 if (state->mutex_acquired)
1133 mutex_unlock(&input_mutex);
1134}
1135
1136static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
1137 unsigned long *bitmap, int max)
1138{
1139 int i;
1140 bool skip_empty = true;
1141 char buf[18];
1142
1143 seq_printf(seq, "B: %s=", name);
1144
1145 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1146 if (input_bits_to_string(buf, sizeof(buf),
1147 bitmap[i], skip_empty)) {
1148 skip_empty = false;
1149 seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
1150 }
1151 }
1152
1153 /*
1154 * If no output was produced print a single 0.
1155 */
1156 if (skip_empty)
1157 seq_putc(seq, '0');
1158
1159 seq_putc(seq, '\n');
1160}
1161
1162static int input_devices_seq_show(struct seq_file *seq, void *v)
1163{
1164 struct input_dev *dev = container_of(v, struct input_dev, node);
1165 const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1166 struct input_handle *handle;
1167
1168 seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
1169 dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
1170
1171 seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
1172 seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
1173 seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
1174 seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1175 seq_puts(seq, "H: Handlers=");
1176
1177 list_for_each_entry(handle, &dev->h_list, d_node)
1178 seq_printf(seq, "%s ", handle->name);
1179 seq_putc(seq, '\n');
1180
1181 input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
1182
1183 input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
1184 if (test_bit(EV_KEY, dev->evbit))
1185 input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
1186 if (test_bit(EV_REL, dev->evbit))
1187 input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
1188 if (test_bit(EV_ABS, dev->evbit))
1189 input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
1190 if (test_bit(EV_MSC, dev->evbit))
1191 input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
1192 if (test_bit(EV_LED, dev->evbit))
1193 input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
1194 if (test_bit(EV_SND, dev->evbit))
1195 input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
1196 if (test_bit(EV_FF, dev->evbit))
1197 input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
1198 if (test_bit(EV_SW, dev->evbit))
1199 input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
1200
1201 seq_putc(seq, '\n');
1202
1203 kfree(path);
1204 return 0;
1205}
1206
1207static const struct seq_operations input_devices_seq_ops = {
1208 .start = input_devices_seq_start,
1209 .next = input_devices_seq_next,
1210 .stop = input_seq_stop,
1211 .show = input_devices_seq_show,
1212};
1213
1214static int input_proc_devices_open(struct inode *inode, struct file *file)
1215{
1216 return seq_open_private(file, &input_devices_seq_ops,
1217 sizeof(struct input_seq_state));
1218}
1219
1220static const struct proc_ops input_devices_proc_ops = {
1221 .proc_open = input_proc_devices_open,
1222 .proc_poll = input_proc_devices_poll,
1223 .proc_read = seq_read,
1224 .proc_lseek = seq_lseek,
1225 .proc_release = seq_release_private,
1226};
1227
1228static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
1229{
1230 struct input_seq_state *state = seq->private;
1231 int error;
1232
1233 error = mutex_lock_interruptible(&input_mutex);
1234 if (error) {
1235 state->mutex_acquired = false;
1236 return ERR_PTR(error);
1237 }
1238
1239 state->mutex_acquired = true;
1240 state->pos = *pos;
1241
1242 return seq_list_start(&input_handler_list, *pos);
1243}
1244
1245static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1246{
1247 struct input_seq_state *state = seq->private;
1248
1249 state->pos = *pos + 1;
1250 return seq_list_next(v, &input_handler_list, pos);
1251}
1252
1253static int input_handlers_seq_show(struct seq_file *seq, void *v)
1254{
1255 struct input_handler *handler = container_of(v, struct input_handler, node);
1256 struct input_seq_state *state = seq->private;
1257
1258 seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
1259 if (handler->filter)
1260 seq_puts(seq, " (filter)");
1261 if (handler->legacy_minors)
1262 seq_printf(seq, " Minor=%d", handler->minor);
1263 seq_putc(seq, '\n');
1264
1265 return 0;
1266}
1267
1268static const struct seq_operations input_handlers_seq_ops = {
1269 .start = input_handlers_seq_start,
1270 .next = input_handlers_seq_next,
1271 .stop = input_seq_stop,
1272 .show = input_handlers_seq_show,
1273};
1274
1275static int input_proc_handlers_open(struct inode *inode, struct file *file)
1276{
1277 return seq_open_private(file, &input_handlers_seq_ops,
1278 sizeof(struct input_seq_state));
1279}
1280
1281static const struct proc_ops input_handlers_proc_ops = {
1282 .proc_open = input_proc_handlers_open,
1283 .proc_read = seq_read,
1284 .proc_lseek = seq_lseek,
1285 .proc_release = seq_release_private,
1286};
1287
1288static int __init input_proc_init(void)
1289{
1290 struct proc_dir_entry *entry;
1291
1292 proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1293 if (!proc_bus_input_dir)
1294 return -ENOMEM;
1295
1296 entry = proc_create("devices", 0, proc_bus_input_dir,
1297 &input_devices_proc_ops);
1298 if (!entry)
1299 goto fail1;
1300
1301 entry = proc_create("handlers", 0, proc_bus_input_dir,
1302 &input_handlers_proc_ops);
1303 if (!entry)
1304 goto fail2;
1305
1306 return 0;
1307
1308 fail2: remove_proc_entry("devices", proc_bus_input_dir);
1309 fail1: remove_proc_entry("bus/input", NULL);
1310 return -ENOMEM;
1311}
1312
1313static void input_proc_exit(void)
1314{
1315 remove_proc_entry("devices", proc_bus_input_dir);
1316 remove_proc_entry("handlers", proc_bus_input_dir);
1317 remove_proc_entry("bus/input", NULL);
1318}
1319
1320#else /* !CONFIG_PROC_FS */
1321static inline void input_wakeup_procfs_readers(void) { }
1322static inline int input_proc_init(void) { return 0; }
1323static inline void input_proc_exit(void) { }
1324#endif
1325
1326#define INPUT_DEV_STRING_ATTR_SHOW(name) \
1327static ssize_t input_dev_show_##name(struct device *dev, \
1328 struct device_attribute *attr, \
1329 char *buf) \
1330{ \
1331 struct input_dev *input_dev = to_input_dev(dev); \
1332 \
1333 return sysfs_emit(buf, "%s\n", \
1334 input_dev->name ? input_dev->name : ""); \
1335} \
1336static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1337
1338INPUT_DEV_STRING_ATTR_SHOW(name);
1339INPUT_DEV_STRING_ATTR_SHOW(phys);
1340INPUT_DEV_STRING_ATTR_SHOW(uniq);
1341
1342static int input_print_modalias_bits(char *buf, int size,
1343 char name, const unsigned long *bm,
1344 unsigned int min_bit, unsigned int max_bit)
1345{
1346 int bit = min_bit;
1347 int len = 0;
1348
1349 len += snprintf(buf, max(size, 0), "%c", name);
1350 for_each_set_bit_from(bit, bm, max_bit)
1351 len += snprintf(buf + len, max(size - len, 0), "%X,", bit);
1352 return len;
1353}
1354
1355static int input_print_modalias_parts(char *buf, int size, int full_len,
1356 const struct input_dev *id)
1357{
1358 int len, klen, remainder, space;
1359
1360 len = snprintf(buf, max(size, 0),
1361 "input:b%04Xv%04Xp%04Xe%04X-",
1362 id->id.bustype, id->id.vendor,
1363 id->id.product, id->id.version);
1364
1365 len += input_print_modalias_bits(buf + len, size - len,
1366 'e', id->evbit, 0, EV_MAX);
1367
1368 /*
1369 * Calculate the remaining space in the buffer making sure we
1370 * have place for the terminating 0.
1371 */
1372 space = max(size - (len + 1), 0);
1373
1374 klen = input_print_modalias_bits(buf + len, size - len,
1375 'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1376 len += klen;
1377
1378 /*
1379 * If we have more data than we can fit in the buffer, check
1380 * if we can trim key data to fit in the rest. We will indicate
1381 * that key data is incomplete by adding "+" sign at the end, like
1382 * this: * "k1,2,3,45,+,".
1383 *
1384 * Note that we shortest key info (if present) is "k+," so we
1385 * can only try to trim if key data is longer than that.
1386 */
1387 if (full_len && size < full_len + 1 && klen > 3) {
1388 remainder = full_len - len;
1389 /*
1390 * We can only trim if we have space for the remainder
1391 * and also for at least "k+," which is 3 more characters.
1392 */
1393 if (remainder <= space - 3) {
1394 /*
1395 * We are guaranteed to have 'k' in the buffer, so
1396 * we need at least 3 additional bytes for storing
1397 * "+," in addition to the remainder.
1398 */
1399 for (int i = size - 1 - remainder - 3; i >= 0; i--) {
1400 if (buf[i] == 'k' || buf[i] == ',') {
1401 strcpy(buf + i + 1, "+,");
1402 len = i + 3; /* Not counting '\0' */
1403 break;
1404 }
1405 }
1406 }
1407 }
1408
1409 len += input_print_modalias_bits(buf + len, size - len,
1410 'r', id->relbit, 0, REL_MAX);
1411 len += input_print_modalias_bits(buf + len, size - len,
1412 'a', id->absbit, 0, ABS_MAX);
1413 len += input_print_modalias_bits(buf + len, size - len,
1414 'm', id->mscbit, 0, MSC_MAX);
1415 len += input_print_modalias_bits(buf + len, size - len,
1416 'l', id->ledbit, 0, LED_MAX);
1417 len += input_print_modalias_bits(buf + len, size - len,
1418 's', id->sndbit, 0, SND_MAX);
1419 len += input_print_modalias_bits(buf + len, size - len,
1420 'f', id->ffbit, 0, FF_MAX);
1421 len += input_print_modalias_bits(buf + len, size - len,
1422 'w', id->swbit, 0, SW_MAX);
1423
1424 return len;
1425}
1426
1427static int input_print_modalias(char *buf, int size, const struct input_dev *id)
1428{
1429 int full_len;
1430
1431 /*
1432 * Printing is done in 2 passes: first one figures out total length
1433 * needed for the modalias string, second one will try to trim key
1434 * data in case when buffer is too small for the entire modalias.
1435 * If the buffer is too small regardless, it will fill as much as it
1436 * can (without trimming key data) into the buffer and leave it to
1437 * the caller to figure out what to do with the result.
1438 */
1439 full_len = input_print_modalias_parts(NULL, 0, 0, id);
1440 return input_print_modalias_parts(buf, size, full_len, id);
1441}
1442
1443static ssize_t input_dev_show_modalias(struct device *dev,
1444 struct device_attribute *attr,
1445 char *buf)
1446{
1447 struct input_dev *id = to_input_dev(dev);
1448 ssize_t len;
1449
1450 len = input_print_modalias(buf, PAGE_SIZE, id);
1451 if (len < PAGE_SIZE - 2)
1452 len += snprintf(buf + len, PAGE_SIZE - len, "\n");
1453
1454 return min_t(int, len, PAGE_SIZE);
1455}
1456static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1457
1458static int input_print_bitmap(char *buf, int buf_size, const unsigned long *bitmap,
1459 int max, int add_cr);
1460
1461static ssize_t input_dev_show_properties(struct device *dev,
1462 struct device_attribute *attr,
1463 char *buf)
1464{
1465 struct input_dev *input_dev = to_input_dev(dev);
1466 int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
1467 INPUT_PROP_MAX, true);
1468 return min_t(int, len, PAGE_SIZE);
1469}
1470static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
1471
1472static int input_inhibit_device(struct input_dev *dev);
1473static int input_uninhibit_device(struct input_dev *dev);
1474
1475static ssize_t inhibited_show(struct device *dev,
1476 struct device_attribute *attr,
1477 char *buf)
1478{
1479 struct input_dev *input_dev = to_input_dev(dev);
1480
1481 return sysfs_emit(buf, "%d\n", input_dev->inhibited);
1482}
1483
1484static ssize_t inhibited_store(struct device *dev,
1485 struct device_attribute *attr, const char *buf,
1486 size_t len)
1487{
1488 struct input_dev *input_dev = to_input_dev(dev);
1489 ssize_t rv;
1490 bool inhibited;
1491
1492 if (kstrtobool(buf, &inhibited))
1493 return -EINVAL;
1494
1495 if (inhibited)
1496 rv = input_inhibit_device(input_dev);
1497 else
1498 rv = input_uninhibit_device(input_dev);
1499
1500 if (rv != 0)
1501 return rv;
1502
1503 return len;
1504}
1505
1506static DEVICE_ATTR_RW(inhibited);
1507
1508static struct attribute *input_dev_attrs[] = {
1509 &dev_attr_name.attr,
1510 &dev_attr_phys.attr,
1511 &dev_attr_uniq.attr,
1512 &dev_attr_modalias.attr,
1513 &dev_attr_properties.attr,
1514 &dev_attr_inhibited.attr,
1515 NULL
1516};
1517
1518static const struct attribute_group input_dev_attr_group = {
1519 .attrs = input_dev_attrs,
1520};
1521
1522#define INPUT_DEV_ID_ATTR(name) \
1523static ssize_t input_dev_show_id_##name(struct device *dev, \
1524 struct device_attribute *attr, \
1525 char *buf) \
1526{ \
1527 struct input_dev *input_dev = to_input_dev(dev); \
1528 return sysfs_emit(buf, "%04x\n", input_dev->id.name); \
1529} \
1530static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1531
1532INPUT_DEV_ID_ATTR(bustype);
1533INPUT_DEV_ID_ATTR(vendor);
1534INPUT_DEV_ID_ATTR(product);
1535INPUT_DEV_ID_ATTR(version);
1536
1537static struct attribute *input_dev_id_attrs[] = {
1538 &dev_attr_bustype.attr,
1539 &dev_attr_vendor.attr,
1540 &dev_attr_product.attr,
1541 &dev_attr_version.attr,
1542 NULL
1543};
1544
1545static const struct attribute_group input_dev_id_attr_group = {
1546 .name = "id",
1547 .attrs = input_dev_id_attrs,
1548};
1549
1550static int input_print_bitmap(char *buf, int buf_size, const unsigned long *bitmap,
1551 int max, int add_cr)
1552{
1553 int i;
1554 int len = 0;
1555 bool skip_empty = true;
1556
1557 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1558 len += input_bits_to_string(buf + len, max(buf_size - len, 0),
1559 bitmap[i], skip_empty);
1560 if (len) {
1561 skip_empty = false;
1562 if (i > 0)
1563 len += snprintf(buf + len, max(buf_size - len, 0), " ");
1564 }
1565 }
1566
1567 /*
1568 * If no output was produced print a single 0.
1569 */
1570 if (len == 0)
1571 len = snprintf(buf, buf_size, "%d", 0);
1572
1573 if (add_cr)
1574 len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1575
1576 return len;
1577}
1578
1579#define INPUT_DEV_CAP_ATTR(ev, bm) \
1580static ssize_t input_dev_show_cap_##bm(struct device *dev, \
1581 struct device_attribute *attr, \
1582 char *buf) \
1583{ \
1584 struct input_dev *input_dev = to_input_dev(dev); \
1585 int len = input_print_bitmap(buf, PAGE_SIZE, \
1586 input_dev->bm##bit, ev##_MAX, \
1587 true); \
1588 return min_t(int, len, PAGE_SIZE); \
1589} \
1590static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1591
1592INPUT_DEV_CAP_ATTR(EV, ev);
1593INPUT_DEV_CAP_ATTR(KEY, key);
1594INPUT_DEV_CAP_ATTR(REL, rel);
1595INPUT_DEV_CAP_ATTR(ABS, abs);
1596INPUT_DEV_CAP_ATTR(MSC, msc);
1597INPUT_DEV_CAP_ATTR(LED, led);
1598INPUT_DEV_CAP_ATTR(SND, snd);
1599INPUT_DEV_CAP_ATTR(FF, ff);
1600INPUT_DEV_CAP_ATTR(SW, sw);
1601
1602static struct attribute *input_dev_caps_attrs[] = {
1603 &dev_attr_ev.attr,
1604 &dev_attr_key.attr,
1605 &dev_attr_rel.attr,
1606 &dev_attr_abs.attr,
1607 &dev_attr_msc.attr,
1608 &dev_attr_led.attr,
1609 &dev_attr_snd.attr,
1610 &dev_attr_ff.attr,
1611 &dev_attr_sw.attr,
1612 NULL
1613};
1614
1615static const struct attribute_group input_dev_caps_attr_group = {
1616 .name = "capabilities",
1617 .attrs = input_dev_caps_attrs,
1618};
1619
1620static const struct attribute_group *input_dev_attr_groups[] = {
1621 &input_dev_attr_group,
1622 &input_dev_id_attr_group,
1623 &input_dev_caps_attr_group,
1624 &input_poller_attribute_group,
1625 NULL
1626};
1627
1628static void input_dev_release(struct device *device)
1629{
1630 struct input_dev *dev = to_input_dev(device);
1631
1632 input_ff_destroy(dev);
1633 input_mt_destroy_slots(dev);
1634 kfree(dev->poller);
1635 kfree(dev->absinfo);
1636 kfree(dev->vals);
1637 kfree(dev);
1638
1639 module_put(THIS_MODULE);
1640}
1641
1642/*
1643 * Input uevent interface - loading event handlers based on
1644 * device bitfields.
1645 */
1646static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1647 const char *name, const unsigned long *bitmap, int max)
1648{
1649 int len;
1650
1651 if (add_uevent_var(env, "%s", name))
1652 return -ENOMEM;
1653
1654 len = input_print_bitmap(&env->buf[env->buflen - 1],
1655 sizeof(env->buf) - env->buflen,
1656 bitmap, max, false);
1657 if (len >= (sizeof(env->buf) - env->buflen))
1658 return -ENOMEM;
1659
1660 env->buflen += len;
1661 return 0;
1662}
1663
1664/*
1665 * This is a pretty gross hack. When building uevent data the driver core
1666 * may try adding more environment variables to kobj_uevent_env without
1667 * telling us, so we have no idea how much of the buffer we can use to
1668 * avoid overflows/-ENOMEM elsewhere. To work around this let's artificially
1669 * reduce amount of memory we will use for the modalias environment variable.
1670 *
1671 * The potential additions are:
1672 *
1673 * SEQNUM=18446744073709551615 - (%llu - 28 bytes)
1674 * HOME=/ (6 bytes)
1675 * PATH=/sbin:/bin:/usr/sbin:/usr/bin (34 bytes)
1676 *
1677 * 68 bytes total. Allow extra buffer - 96 bytes
1678 */
1679#define UEVENT_ENV_EXTRA_LEN 96
1680
1681static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1682 const struct input_dev *dev)
1683{
1684 int len;
1685
1686 if (add_uevent_var(env, "MODALIAS="))
1687 return -ENOMEM;
1688
1689 len = input_print_modalias(&env->buf[env->buflen - 1],
1690 (int)sizeof(env->buf) - env->buflen -
1691 UEVENT_ENV_EXTRA_LEN,
1692 dev);
1693 if (len >= ((int)sizeof(env->buf) - env->buflen -
1694 UEVENT_ENV_EXTRA_LEN))
1695 return -ENOMEM;
1696
1697 env->buflen += len;
1698 return 0;
1699}
1700
1701#define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \
1702 do { \
1703 int err = add_uevent_var(env, fmt, val); \
1704 if (err) \
1705 return err; \
1706 } while (0)
1707
1708#define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max) \
1709 do { \
1710 int err = input_add_uevent_bm_var(env, name, bm, max); \
1711 if (err) \
1712 return err; \
1713 } while (0)
1714
1715#define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \
1716 do { \
1717 int err = input_add_uevent_modalias_var(env, dev); \
1718 if (err) \
1719 return err; \
1720 } while (0)
1721
1722static int input_dev_uevent(const struct device *device, struct kobj_uevent_env *env)
1723{
1724 const struct input_dev *dev = to_input_dev(device);
1725
1726 INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1727 dev->id.bustype, dev->id.vendor,
1728 dev->id.product, dev->id.version);
1729 if (dev->name)
1730 INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1731 if (dev->phys)
1732 INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1733 if (dev->uniq)
1734 INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1735
1736 INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
1737
1738 INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1739 if (test_bit(EV_KEY, dev->evbit))
1740 INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1741 if (test_bit(EV_REL, dev->evbit))
1742 INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1743 if (test_bit(EV_ABS, dev->evbit))
1744 INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1745 if (test_bit(EV_MSC, dev->evbit))
1746 INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1747 if (test_bit(EV_LED, dev->evbit))
1748 INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1749 if (test_bit(EV_SND, dev->evbit))
1750 INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1751 if (test_bit(EV_FF, dev->evbit))
1752 INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1753 if (test_bit(EV_SW, dev->evbit))
1754 INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1755
1756 INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1757
1758 return 0;
1759}
1760
1761#define INPUT_DO_TOGGLE(dev, type, bits, on) \
1762 do { \
1763 int i; \
1764 bool active; \
1765 \
1766 if (!test_bit(EV_##type, dev->evbit)) \
1767 break; \
1768 \
1769 for_each_set_bit(i, dev->bits##bit, type##_CNT) { \
1770 active = test_bit(i, dev->bits); \
1771 if (!active && !on) \
1772 continue; \
1773 \
1774 dev->event(dev, EV_##type, i, on ? active : 0); \
1775 } \
1776 } while (0)
1777
1778static void input_dev_toggle(struct input_dev *dev, bool activate)
1779{
1780 if (!dev->event)
1781 return;
1782
1783 INPUT_DO_TOGGLE(dev, LED, led, activate);
1784 INPUT_DO_TOGGLE(dev, SND, snd, activate);
1785
1786 if (activate && test_bit(EV_REP, dev->evbit)) {
1787 dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1788 dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1789 }
1790}
1791
1792/**
1793 * input_reset_device() - reset/restore the state of input device
1794 * @dev: input device whose state needs to be reset
1795 *
1796 * This function tries to reset the state of an opened input device and
1797 * bring internal state and state if the hardware in sync with each other.
1798 * We mark all keys as released, restore LED state, repeat rate, etc.
1799 */
1800void input_reset_device(struct input_dev *dev)
1801{
1802 unsigned long flags;
1803
1804 mutex_lock(&dev->mutex);
1805 spin_lock_irqsave(&dev->event_lock, flags);
1806
1807 input_dev_toggle(dev, true);
1808 if (input_dev_release_keys(dev))
1809 input_handle_event(dev, EV_SYN, SYN_REPORT, 1);
1810
1811 spin_unlock_irqrestore(&dev->event_lock, flags);
1812 mutex_unlock(&dev->mutex);
1813}
1814EXPORT_SYMBOL(input_reset_device);
1815
1816static int input_inhibit_device(struct input_dev *dev)
1817{
1818 mutex_lock(&dev->mutex);
1819
1820 if (dev->inhibited)
1821 goto out;
1822
1823 if (dev->users) {
1824 if (dev->close)
1825 dev->close(dev);
1826 if (dev->poller)
1827 input_dev_poller_stop(dev->poller);
1828 }
1829
1830 spin_lock_irq(&dev->event_lock);
1831 input_mt_release_slots(dev);
1832 input_dev_release_keys(dev);
1833 input_handle_event(dev, EV_SYN, SYN_REPORT, 1);
1834 input_dev_toggle(dev, false);
1835 spin_unlock_irq(&dev->event_lock);
1836
1837 dev->inhibited = true;
1838
1839out:
1840 mutex_unlock(&dev->mutex);
1841 return 0;
1842}
1843
1844static int input_uninhibit_device(struct input_dev *dev)
1845{
1846 int ret = 0;
1847
1848 mutex_lock(&dev->mutex);
1849
1850 if (!dev->inhibited)
1851 goto out;
1852
1853 if (dev->users) {
1854 if (dev->open) {
1855 ret = dev->open(dev);
1856 if (ret)
1857 goto out;
1858 }
1859 if (dev->poller)
1860 input_dev_poller_start(dev->poller);
1861 }
1862
1863 dev->inhibited = false;
1864 spin_lock_irq(&dev->event_lock);
1865 input_dev_toggle(dev, true);
1866 spin_unlock_irq(&dev->event_lock);
1867
1868out:
1869 mutex_unlock(&dev->mutex);
1870 return ret;
1871}
1872
1873static int input_dev_suspend(struct device *dev)
1874{
1875 struct input_dev *input_dev = to_input_dev(dev);
1876
1877 spin_lock_irq(&input_dev->event_lock);
1878
1879 /*
1880 * Keys that are pressed now are unlikely to be
1881 * still pressed when we resume.
1882 */
1883 if (input_dev_release_keys(input_dev))
1884 input_handle_event(input_dev, EV_SYN, SYN_REPORT, 1);
1885
1886 /* Turn off LEDs and sounds, if any are active. */
1887 input_dev_toggle(input_dev, false);
1888
1889 spin_unlock_irq(&input_dev->event_lock);
1890
1891 return 0;
1892}
1893
1894static int input_dev_resume(struct device *dev)
1895{
1896 struct input_dev *input_dev = to_input_dev(dev);
1897
1898 spin_lock_irq(&input_dev->event_lock);
1899
1900 /* Restore state of LEDs and sounds, if any were active. */
1901 input_dev_toggle(input_dev, true);
1902
1903 spin_unlock_irq(&input_dev->event_lock);
1904
1905 return 0;
1906}
1907
1908static int input_dev_freeze(struct device *dev)
1909{
1910 struct input_dev *input_dev = to_input_dev(dev);
1911
1912 spin_lock_irq(&input_dev->event_lock);
1913
1914 /*
1915 * Keys that are pressed now are unlikely to be
1916 * still pressed when we resume.
1917 */
1918 if (input_dev_release_keys(input_dev))
1919 input_handle_event(input_dev, EV_SYN, SYN_REPORT, 1);
1920
1921 spin_unlock_irq(&input_dev->event_lock);
1922
1923 return 0;
1924}
1925
1926static int input_dev_poweroff(struct device *dev)
1927{
1928 struct input_dev *input_dev = to_input_dev(dev);
1929
1930 spin_lock_irq(&input_dev->event_lock);
1931
1932 /* Turn off LEDs and sounds, if any are active. */
1933 input_dev_toggle(input_dev, false);
1934
1935 spin_unlock_irq(&input_dev->event_lock);
1936
1937 return 0;
1938}
1939
1940static const struct dev_pm_ops input_dev_pm_ops = {
1941 .suspend = input_dev_suspend,
1942 .resume = input_dev_resume,
1943 .freeze = input_dev_freeze,
1944 .poweroff = input_dev_poweroff,
1945 .restore = input_dev_resume,
1946};
1947
1948static const struct device_type input_dev_type = {
1949 .groups = input_dev_attr_groups,
1950 .release = input_dev_release,
1951 .uevent = input_dev_uevent,
1952 .pm = pm_sleep_ptr(&input_dev_pm_ops),
1953};
1954
1955static char *input_devnode(const struct device *dev, umode_t *mode)
1956{
1957 return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
1958}
1959
1960const struct class input_class = {
1961 .name = "input",
1962 .devnode = input_devnode,
1963};
1964EXPORT_SYMBOL_GPL(input_class);
1965
1966/**
1967 * input_allocate_device - allocate memory for new input device
1968 *
1969 * Returns prepared struct input_dev or %NULL.
1970 *
1971 * NOTE: Use input_free_device() to free devices that have not been
1972 * registered; input_unregister_device() should be used for already
1973 * registered devices.
1974 */
1975struct input_dev *input_allocate_device(void)
1976{
1977 static atomic_t input_no = ATOMIC_INIT(-1);
1978 struct input_dev *dev;
1979
1980 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1981 if (!dev)
1982 return NULL;
1983
1984 /*
1985 * Start with space for SYN_REPORT + 7 EV_KEY/EV_MSC events + 2 spare,
1986 * see input_estimate_events_per_packet(). We will tune the number
1987 * when we register the device.
1988 */
1989 dev->max_vals = 10;
1990 dev->vals = kcalloc(dev->max_vals, sizeof(*dev->vals), GFP_KERNEL);
1991 if (!dev->vals) {
1992 kfree(dev);
1993 return NULL;
1994 }
1995
1996 mutex_init(&dev->mutex);
1997 spin_lock_init(&dev->event_lock);
1998 timer_setup(&dev->timer, NULL, 0);
1999 INIT_LIST_HEAD(&dev->h_list);
2000 INIT_LIST_HEAD(&dev->node);
2001
2002 dev->dev.type = &input_dev_type;
2003 dev->dev.class = &input_class;
2004 device_initialize(&dev->dev);
2005 /*
2006 * From this point on we can no longer simply "kfree(dev)", we need
2007 * to use input_free_device() so that device core properly frees its
2008 * resources associated with the input device.
2009 */
2010
2011 dev_set_name(&dev->dev, "input%lu",
2012 (unsigned long)atomic_inc_return(&input_no));
2013
2014 __module_get(THIS_MODULE);
2015
2016 return dev;
2017}
2018EXPORT_SYMBOL(input_allocate_device);
2019
2020struct input_devres {
2021 struct input_dev *input;
2022};
2023
2024static int devm_input_device_match(struct device *dev, void *res, void *data)
2025{
2026 struct input_devres *devres = res;
2027
2028 return devres->input == data;
2029}
2030
2031static void devm_input_device_release(struct device *dev, void *res)
2032{
2033 struct input_devres *devres = res;
2034 struct input_dev *input = devres->input;
2035
2036 dev_dbg(dev, "%s: dropping reference to %s\n",
2037 __func__, dev_name(&input->dev));
2038 input_put_device(input);
2039}
2040
2041/**
2042 * devm_input_allocate_device - allocate managed input device
2043 * @dev: device owning the input device being created
2044 *
2045 * Returns prepared struct input_dev or %NULL.
2046 *
2047 * Managed input devices do not need to be explicitly unregistered or
2048 * freed as it will be done automatically when owner device unbinds from
2049 * its driver (or binding fails). Once managed input device is allocated,
2050 * it is ready to be set up and registered in the same fashion as regular
2051 * input device. There are no special devm_input_device_[un]register()
2052 * variants, regular ones work with both managed and unmanaged devices,
2053 * should you need them. In most cases however, managed input device need
2054 * not be explicitly unregistered or freed.
2055 *
2056 * NOTE: the owner device is set up as parent of input device and users
2057 * should not override it.
2058 */
2059struct input_dev *devm_input_allocate_device(struct device *dev)
2060{
2061 struct input_dev *input;
2062 struct input_devres *devres;
2063
2064 devres = devres_alloc(devm_input_device_release,
2065 sizeof(*devres), GFP_KERNEL);
2066 if (!devres)
2067 return NULL;
2068
2069 input = input_allocate_device();
2070 if (!input) {
2071 devres_free(devres);
2072 return NULL;
2073 }
2074
2075 input->dev.parent = dev;
2076 input->devres_managed = true;
2077
2078 devres->input = input;
2079 devres_add(dev, devres);
2080
2081 return input;
2082}
2083EXPORT_SYMBOL(devm_input_allocate_device);
2084
2085/**
2086 * input_free_device - free memory occupied by input_dev structure
2087 * @dev: input device to free
2088 *
2089 * This function should only be used if input_register_device()
2090 * was not called yet or if it failed. Once device was registered
2091 * use input_unregister_device() and memory will be freed once last
2092 * reference to the device is dropped.
2093 *
2094 * Device should be allocated by input_allocate_device().
2095 *
2096 * NOTE: If there are references to the input device then memory
2097 * will not be freed until last reference is dropped.
2098 */
2099void input_free_device(struct input_dev *dev)
2100{
2101 if (dev) {
2102 if (dev->devres_managed)
2103 WARN_ON(devres_destroy(dev->dev.parent,
2104 devm_input_device_release,
2105 devm_input_device_match,
2106 dev));
2107 input_put_device(dev);
2108 }
2109}
2110EXPORT_SYMBOL(input_free_device);
2111
2112/**
2113 * input_set_timestamp - set timestamp for input events
2114 * @dev: input device to set timestamp for
2115 * @timestamp: the time at which the event has occurred
2116 * in CLOCK_MONOTONIC
2117 *
2118 * This function is intended to provide to the input system a more
2119 * accurate time of when an event actually occurred. The driver should
2120 * call this function as soon as a timestamp is acquired ensuring
2121 * clock conversions in input_set_timestamp are done correctly.
2122 *
2123 * The system entering suspend state between timestamp acquisition and
2124 * calling input_set_timestamp can result in inaccurate conversions.
2125 */
2126void input_set_timestamp(struct input_dev *dev, ktime_t timestamp)
2127{
2128 dev->timestamp[INPUT_CLK_MONO] = timestamp;
2129 dev->timestamp[INPUT_CLK_REAL] = ktime_mono_to_real(timestamp);
2130 dev->timestamp[INPUT_CLK_BOOT] = ktime_mono_to_any(timestamp,
2131 TK_OFFS_BOOT);
2132}
2133EXPORT_SYMBOL(input_set_timestamp);
2134
2135/**
2136 * input_get_timestamp - get timestamp for input events
2137 * @dev: input device to get timestamp from
2138 *
2139 * A valid timestamp is a timestamp of non-zero value.
2140 */
2141ktime_t *input_get_timestamp(struct input_dev *dev)
2142{
2143 const ktime_t invalid_timestamp = ktime_set(0, 0);
2144
2145 if (!ktime_compare(dev->timestamp[INPUT_CLK_MONO], invalid_timestamp))
2146 input_set_timestamp(dev, ktime_get());
2147
2148 return dev->timestamp;
2149}
2150EXPORT_SYMBOL(input_get_timestamp);
2151
2152/**
2153 * input_set_capability - mark device as capable of a certain event
2154 * @dev: device that is capable of emitting or accepting event
2155 * @type: type of the event (EV_KEY, EV_REL, etc...)
2156 * @code: event code
2157 *
2158 * In addition to setting up corresponding bit in appropriate capability
2159 * bitmap the function also adjusts dev->evbit.
2160 */
2161void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
2162{
2163 if (type < EV_CNT && input_max_code[type] &&
2164 code > input_max_code[type]) {
2165 pr_err("%s: invalid code %u for type %u\n", __func__, code,
2166 type);
2167 dump_stack();
2168 return;
2169 }
2170
2171 switch (type) {
2172 case EV_KEY:
2173 __set_bit(code, dev->keybit);
2174 break;
2175
2176 case EV_REL:
2177 __set_bit(code, dev->relbit);
2178 break;
2179
2180 case EV_ABS:
2181 input_alloc_absinfo(dev);
2182 __set_bit(code, dev->absbit);
2183 break;
2184
2185 case EV_MSC:
2186 __set_bit(code, dev->mscbit);
2187 break;
2188
2189 case EV_SW:
2190 __set_bit(code, dev->swbit);
2191 break;
2192
2193 case EV_LED:
2194 __set_bit(code, dev->ledbit);
2195 break;
2196
2197 case EV_SND:
2198 __set_bit(code, dev->sndbit);
2199 break;
2200
2201 case EV_FF:
2202 __set_bit(code, dev->ffbit);
2203 break;
2204
2205 case EV_PWR:
2206 /* do nothing */
2207 break;
2208
2209 default:
2210 pr_err("%s: unknown type %u (code %u)\n", __func__, type, code);
2211 dump_stack();
2212 return;
2213 }
2214
2215 __set_bit(type, dev->evbit);
2216}
2217EXPORT_SYMBOL(input_set_capability);
2218
2219static unsigned int input_estimate_events_per_packet(struct input_dev *dev)
2220{
2221 int mt_slots;
2222 int i;
2223 unsigned int events;
2224
2225 if (dev->mt) {
2226 mt_slots = dev->mt->num_slots;
2227 } else if (test_bit(ABS_MT_TRACKING_ID, dev->absbit)) {
2228 mt_slots = dev->absinfo[ABS_MT_TRACKING_ID].maximum -
2229 dev->absinfo[ABS_MT_TRACKING_ID].minimum + 1;
2230 mt_slots = clamp(mt_slots, 2, 32);
2231 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
2232 mt_slots = 2;
2233 } else {
2234 mt_slots = 0;
2235 }
2236
2237 events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */
2238
2239 if (test_bit(EV_ABS, dev->evbit))
2240 for_each_set_bit(i, dev->absbit, ABS_CNT)
2241 events += input_is_mt_axis(i) ? mt_slots : 1;
2242
2243 if (test_bit(EV_REL, dev->evbit))
2244 events += bitmap_weight(dev->relbit, REL_CNT);
2245
2246 /* Make room for KEY and MSC events */
2247 events += 7;
2248
2249 return events;
2250}
2251
2252#define INPUT_CLEANSE_BITMASK(dev, type, bits) \
2253 do { \
2254 if (!test_bit(EV_##type, dev->evbit)) \
2255 memset(dev->bits##bit, 0, \
2256 sizeof(dev->bits##bit)); \
2257 } while (0)
2258
2259static void input_cleanse_bitmasks(struct input_dev *dev)
2260{
2261 INPUT_CLEANSE_BITMASK(dev, KEY, key);
2262 INPUT_CLEANSE_BITMASK(dev, REL, rel);
2263 INPUT_CLEANSE_BITMASK(dev, ABS, abs);
2264 INPUT_CLEANSE_BITMASK(dev, MSC, msc);
2265 INPUT_CLEANSE_BITMASK(dev, LED, led);
2266 INPUT_CLEANSE_BITMASK(dev, SND, snd);
2267 INPUT_CLEANSE_BITMASK(dev, FF, ff);
2268 INPUT_CLEANSE_BITMASK(dev, SW, sw);
2269}
2270
2271static void __input_unregister_device(struct input_dev *dev)
2272{
2273 struct input_handle *handle, *next;
2274
2275 input_disconnect_device(dev);
2276
2277 mutex_lock(&input_mutex);
2278
2279 list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
2280 handle->handler->disconnect(handle);
2281 WARN_ON(!list_empty(&dev->h_list));
2282
2283 del_timer_sync(&dev->timer);
2284 list_del_init(&dev->node);
2285
2286 input_wakeup_procfs_readers();
2287
2288 mutex_unlock(&input_mutex);
2289
2290 device_del(&dev->dev);
2291}
2292
2293static void devm_input_device_unregister(struct device *dev, void *res)
2294{
2295 struct input_devres *devres = res;
2296 struct input_dev *input = devres->input;
2297
2298 dev_dbg(dev, "%s: unregistering device %s\n",
2299 __func__, dev_name(&input->dev));
2300 __input_unregister_device(input);
2301}
2302
2303/*
2304 * Generate software autorepeat event. Note that we take
2305 * dev->event_lock here to avoid racing with input_event
2306 * which may cause keys get "stuck".
2307 */
2308static void input_repeat_key(struct timer_list *t)
2309{
2310 struct input_dev *dev = from_timer(dev, t, timer);
2311 unsigned long flags;
2312
2313 spin_lock_irqsave(&dev->event_lock, flags);
2314
2315 if (!dev->inhibited &&
2316 test_bit(dev->repeat_key, dev->key) &&
2317 is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
2318
2319 input_set_timestamp(dev, ktime_get());
2320 input_handle_event(dev, EV_KEY, dev->repeat_key, 2);
2321 input_handle_event(dev, EV_SYN, SYN_REPORT, 1);
2322
2323 if (dev->rep[REP_PERIOD])
2324 mod_timer(&dev->timer, jiffies +
2325 msecs_to_jiffies(dev->rep[REP_PERIOD]));
2326 }
2327
2328 spin_unlock_irqrestore(&dev->event_lock, flags);
2329}
2330
2331/**
2332 * input_enable_softrepeat - enable software autorepeat
2333 * @dev: input device
2334 * @delay: repeat delay
2335 * @period: repeat period
2336 *
2337 * Enable software autorepeat on the input device.
2338 */
2339void input_enable_softrepeat(struct input_dev *dev, int delay, int period)
2340{
2341 dev->timer.function = input_repeat_key;
2342 dev->rep[REP_DELAY] = delay;
2343 dev->rep[REP_PERIOD] = period;
2344}
2345EXPORT_SYMBOL(input_enable_softrepeat);
2346
2347bool input_device_enabled(struct input_dev *dev)
2348{
2349 lockdep_assert_held(&dev->mutex);
2350
2351 return !dev->inhibited && dev->users > 0;
2352}
2353EXPORT_SYMBOL_GPL(input_device_enabled);
2354
2355static int input_device_tune_vals(struct input_dev *dev)
2356{
2357 struct input_value *vals;
2358 unsigned int packet_size;
2359 unsigned int max_vals;
2360
2361 packet_size = input_estimate_events_per_packet(dev);
2362 if (dev->hint_events_per_packet < packet_size)
2363 dev->hint_events_per_packet = packet_size;
2364
2365 max_vals = dev->hint_events_per_packet + 2;
2366 if (dev->max_vals >= max_vals)
2367 return 0;
2368
2369 vals = kcalloc(max_vals, sizeof(*vals), GFP_KERNEL);
2370 if (!vals)
2371 return -ENOMEM;
2372
2373 spin_lock_irq(&dev->event_lock);
2374 dev->max_vals = max_vals;
2375 swap(dev->vals, vals);
2376 spin_unlock_irq(&dev->event_lock);
2377
2378 /* Because of swap() above, this frees the old vals memory */
2379 kfree(vals);
2380
2381 return 0;
2382}
2383
2384/**
2385 * input_register_device - register device with input core
2386 * @dev: device to be registered
2387 *
2388 * This function registers device with input core. The device must be
2389 * allocated with input_allocate_device() and all it's capabilities
2390 * set up before registering.
2391 * If function fails the device must be freed with input_free_device().
2392 * Once device has been successfully registered it can be unregistered
2393 * with input_unregister_device(); input_free_device() should not be
2394 * called in this case.
2395 *
2396 * Note that this function is also used to register managed input devices
2397 * (ones allocated with devm_input_allocate_device()). Such managed input
2398 * devices need not be explicitly unregistered or freed, their tear down
2399 * is controlled by the devres infrastructure. It is also worth noting
2400 * that tear down of managed input devices is internally a 2-step process:
2401 * registered managed input device is first unregistered, but stays in
2402 * memory and can still handle input_event() calls (although events will
2403 * not be delivered anywhere). The freeing of managed input device will
2404 * happen later, when devres stack is unwound to the point where device
2405 * allocation was made.
2406 */
2407int input_register_device(struct input_dev *dev)
2408{
2409 struct input_devres *devres = NULL;
2410 struct input_handler *handler;
2411 const char *path;
2412 int error;
2413
2414 if (test_bit(EV_ABS, dev->evbit) && !dev->absinfo) {
2415 dev_err(&dev->dev,
2416 "Absolute device without dev->absinfo, refusing to register\n");
2417 return -EINVAL;
2418 }
2419
2420 if (dev->devres_managed) {
2421 devres = devres_alloc(devm_input_device_unregister,
2422 sizeof(*devres), GFP_KERNEL);
2423 if (!devres)
2424 return -ENOMEM;
2425
2426 devres->input = dev;
2427 }
2428
2429 /* Every input device generates EV_SYN/SYN_REPORT events. */
2430 __set_bit(EV_SYN, dev->evbit);
2431
2432 /* KEY_RESERVED is not supposed to be transmitted to userspace. */
2433 __clear_bit(KEY_RESERVED, dev->keybit);
2434
2435 /* Make sure that bitmasks not mentioned in dev->evbit are clean. */
2436 input_cleanse_bitmasks(dev);
2437
2438 error = input_device_tune_vals(dev);
2439 if (error)
2440 goto err_devres_free;
2441
2442 /*
2443 * If delay and period are pre-set by the driver, then autorepeating
2444 * is handled by the driver itself and we don't do it in input.c.
2445 */
2446 if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD])
2447 input_enable_softrepeat(dev, 250, 33);
2448
2449 if (!dev->getkeycode)
2450 dev->getkeycode = input_default_getkeycode;
2451
2452 if (!dev->setkeycode)
2453 dev->setkeycode = input_default_setkeycode;
2454
2455 if (dev->poller)
2456 input_dev_poller_finalize(dev->poller);
2457
2458 error = device_add(&dev->dev);
2459 if (error)
2460 goto err_devres_free;
2461
2462 path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
2463 pr_info("%s as %s\n",
2464 dev->name ? dev->name : "Unspecified device",
2465 path ? path : "N/A");
2466 kfree(path);
2467
2468 error = mutex_lock_interruptible(&input_mutex);
2469 if (error)
2470 goto err_device_del;
2471
2472 list_add_tail(&dev->node, &input_dev_list);
2473
2474 list_for_each_entry(handler, &input_handler_list, node)
2475 input_attach_handler(dev, handler);
2476
2477 input_wakeup_procfs_readers();
2478
2479 mutex_unlock(&input_mutex);
2480
2481 if (dev->devres_managed) {
2482 dev_dbg(dev->dev.parent, "%s: registering %s with devres.\n",
2483 __func__, dev_name(&dev->dev));
2484 devres_add(dev->dev.parent, devres);
2485 }
2486 return 0;
2487
2488err_device_del:
2489 device_del(&dev->dev);
2490err_devres_free:
2491 devres_free(devres);
2492 return error;
2493}
2494EXPORT_SYMBOL(input_register_device);
2495
2496/**
2497 * input_unregister_device - unregister previously registered device
2498 * @dev: device to be unregistered
2499 *
2500 * This function unregisters an input device. Once device is unregistered
2501 * the caller should not try to access it as it may get freed at any moment.
2502 */
2503void input_unregister_device(struct input_dev *dev)
2504{
2505 if (dev->devres_managed) {
2506 WARN_ON(devres_destroy(dev->dev.parent,
2507 devm_input_device_unregister,
2508 devm_input_device_match,
2509 dev));
2510 __input_unregister_device(dev);
2511 /*
2512 * We do not do input_put_device() here because it will be done
2513 * when 2nd devres fires up.
2514 */
2515 } else {
2516 __input_unregister_device(dev);
2517 input_put_device(dev);
2518 }
2519}
2520EXPORT_SYMBOL(input_unregister_device);
2521
2522static int input_handler_check_methods(const struct input_handler *handler)
2523{
2524 int count = 0;
2525
2526 if (handler->filter)
2527 count++;
2528 if (handler->events)
2529 count++;
2530 if (handler->event)
2531 count++;
2532
2533 if (count > 1) {
2534 pr_err("%s: only one event processing method can be defined (%s)\n",
2535 __func__, handler->name);
2536 return -EINVAL;
2537 }
2538
2539 return 0;
2540}
2541
2542/**
2543 * input_register_handler - register a new input handler
2544 * @handler: handler to be registered
2545 *
2546 * This function registers a new input handler (interface) for input
2547 * devices in the system and attaches it to all input devices that
2548 * are compatible with the handler.
2549 */
2550int input_register_handler(struct input_handler *handler)
2551{
2552 struct input_dev *dev;
2553 int error;
2554
2555 error = input_handler_check_methods(handler);
2556 if (error)
2557 return error;
2558
2559 INIT_LIST_HEAD(&handler->h_list);
2560
2561 error = mutex_lock_interruptible(&input_mutex);
2562 if (error)
2563 return error;
2564
2565 list_add_tail(&handler->node, &input_handler_list);
2566
2567 list_for_each_entry(dev, &input_dev_list, node)
2568 input_attach_handler(dev, handler);
2569
2570 input_wakeup_procfs_readers();
2571
2572 mutex_unlock(&input_mutex);
2573 return 0;
2574}
2575EXPORT_SYMBOL(input_register_handler);
2576
2577/**
2578 * input_unregister_handler - unregisters an input handler
2579 * @handler: handler to be unregistered
2580 *
2581 * This function disconnects a handler from its input devices and
2582 * removes it from lists of known handlers.
2583 */
2584void input_unregister_handler(struct input_handler *handler)
2585{
2586 struct input_handle *handle, *next;
2587
2588 mutex_lock(&input_mutex);
2589
2590 list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
2591 handler->disconnect(handle);
2592 WARN_ON(!list_empty(&handler->h_list));
2593
2594 list_del_init(&handler->node);
2595
2596 input_wakeup_procfs_readers();
2597
2598 mutex_unlock(&input_mutex);
2599}
2600EXPORT_SYMBOL(input_unregister_handler);
2601
2602/**
2603 * input_handler_for_each_handle - handle iterator
2604 * @handler: input handler to iterate
2605 * @data: data for the callback
2606 * @fn: function to be called for each handle
2607 *
2608 * Iterate over @bus's list of devices, and call @fn for each, passing
2609 * it @data and stop when @fn returns a non-zero value. The function is
2610 * using RCU to traverse the list and therefore may be using in atomic
2611 * contexts. The @fn callback is invoked from RCU critical section and
2612 * thus must not sleep.
2613 */
2614int input_handler_for_each_handle(struct input_handler *handler, void *data,
2615 int (*fn)(struct input_handle *, void *))
2616{
2617 struct input_handle *handle;
2618 int retval = 0;
2619
2620 rcu_read_lock();
2621
2622 list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
2623 retval = fn(handle, data);
2624 if (retval)
2625 break;
2626 }
2627
2628 rcu_read_unlock();
2629
2630 return retval;
2631}
2632EXPORT_SYMBOL(input_handler_for_each_handle);
2633
2634/*
2635 * An implementation of input_handle's handle_events() method that simply
2636 * invokes handler->event() method for each event one by one.
2637 */
2638static unsigned int input_handle_events_default(struct input_handle *handle,
2639 struct input_value *vals,
2640 unsigned int count)
2641{
2642 struct input_handler *handler = handle->handler;
2643 struct input_value *v;
2644
2645 for (v = vals; v != vals + count; v++)
2646 handler->event(handle, v->type, v->code, v->value);
2647
2648 return count;
2649}
2650
2651/*
2652 * An implementation of input_handle's handle_events() method that invokes
2653 * handler->filter() method for each event one by one and removes events
2654 * that were filtered out from the "vals" array.
2655 */
2656static unsigned int input_handle_events_filter(struct input_handle *handle,
2657 struct input_value *vals,
2658 unsigned int count)
2659{
2660 struct input_handler *handler = handle->handler;
2661 struct input_value *end = vals;
2662 struct input_value *v;
2663
2664 for (v = vals; v != vals + count; v++) {
2665 if (handler->filter(handle, v->type, v->code, v->value))
2666 continue;
2667 if (end != v)
2668 *end = *v;
2669 end++;
2670 }
2671
2672 return end - vals;
2673}
2674
2675/*
2676 * An implementation of input_handle's handle_events() method that does nothing.
2677 */
2678static unsigned int input_handle_events_null(struct input_handle *handle,
2679 struct input_value *vals,
2680 unsigned int count)
2681{
2682 return count;
2683}
2684
2685/*
2686 * Sets up appropriate handle->event_handler based on the input_handler
2687 * associated with the handle.
2688 */
2689static void input_handle_setup_event_handler(struct input_handle *handle)
2690{
2691 struct input_handler *handler = handle->handler;
2692
2693 if (handler->filter)
2694 handle->handle_events = input_handle_events_filter;
2695 else if (handler->event)
2696 handle->handle_events = input_handle_events_default;
2697 else if (handler->events)
2698 handle->handle_events = handler->events;
2699 else
2700 handle->handle_events = input_handle_events_null;
2701}
2702
2703/**
2704 * input_register_handle - register a new input handle
2705 * @handle: handle to register
2706 *
2707 * This function puts a new input handle onto device's
2708 * and handler's lists so that events can flow through
2709 * it once it is opened using input_open_device().
2710 *
2711 * This function is supposed to be called from handler's
2712 * connect() method.
2713 */
2714int input_register_handle(struct input_handle *handle)
2715{
2716 struct input_handler *handler = handle->handler;
2717 struct input_dev *dev = handle->dev;
2718 int error;
2719
2720 input_handle_setup_event_handler(handle);
2721 /*
2722 * We take dev->mutex here to prevent race with
2723 * input_release_device().
2724 */
2725 error = mutex_lock_interruptible(&dev->mutex);
2726 if (error)
2727 return error;
2728
2729 /*
2730 * Filters go to the head of the list, normal handlers
2731 * to the tail.
2732 */
2733 if (handler->filter)
2734 list_add_rcu(&handle->d_node, &dev->h_list);
2735 else
2736 list_add_tail_rcu(&handle->d_node, &dev->h_list);
2737
2738 mutex_unlock(&dev->mutex);
2739
2740 /*
2741 * Since we are supposed to be called from ->connect()
2742 * which is mutually exclusive with ->disconnect()
2743 * we can't be racing with input_unregister_handle()
2744 * and so separate lock is not needed here.
2745 */
2746 list_add_tail_rcu(&handle->h_node, &handler->h_list);
2747
2748 if (handler->start)
2749 handler->start(handle);
2750
2751 return 0;
2752}
2753EXPORT_SYMBOL(input_register_handle);
2754
2755/**
2756 * input_unregister_handle - unregister an input handle
2757 * @handle: handle to unregister
2758 *
2759 * This function removes input handle from device's
2760 * and handler's lists.
2761 *
2762 * This function is supposed to be called from handler's
2763 * disconnect() method.
2764 */
2765void input_unregister_handle(struct input_handle *handle)
2766{
2767 struct input_dev *dev = handle->dev;
2768
2769 list_del_rcu(&handle->h_node);
2770
2771 /*
2772 * Take dev->mutex to prevent race with input_release_device().
2773 */
2774 mutex_lock(&dev->mutex);
2775 list_del_rcu(&handle->d_node);
2776 mutex_unlock(&dev->mutex);
2777
2778 synchronize_rcu();
2779}
2780EXPORT_SYMBOL(input_unregister_handle);
2781
2782/**
2783 * input_get_new_minor - allocates a new input minor number
2784 * @legacy_base: beginning or the legacy range to be searched
2785 * @legacy_num: size of legacy range
2786 * @allow_dynamic: whether we can also take ID from the dynamic range
2787 *
2788 * This function allocates a new device minor for from input major namespace.
2789 * Caller can request legacy minor by specifying @legacy_base and @legacy_num
2790 * parameters and whether ID can be allocated from dynamic range if there are
2791 * no free IDs in legacy range.
2792 */
2793int input_get_new_minor(int legacy_base, unsigned int legacy_num,
2794 bool allow_dynamic)
2795{
2796 /*
2797 * This function should be called from input handler's ->connect()
2798 * methods, which are serialized with input_mutex, so no additional
2799 * locking is needed here.
2800 */
2801 if (legacy_base >= 0) {
2802 int minor = ida_alloc_range(&input_ida, legacy_base,
2803 legacy_base + legacy_num - 1,
2804 GFP_KERNEL);
2805 if (minor >= 0 || !allow_dynamic)
2806 return minor;
2807 }
2808
2809 return ida_alloc_range(&input_ida, INPUT_FIRST_DYNAMIC_DEV,
2810 INPUT_MAX_CHAR_DEVICES - 1, GFP_KERNEL);
2811}
2812EXPORT_SYMBOL(input_get_new_minor);
2813
2814/**
2815 * input_free_minor - release previously allocated minor
2816 * @minor: minor to be released
2817 *
2818 * This function releases previously allocated input minor so that it can be
2819 * reused later.
2820 */
2821void input_free_minor(unsigned int minor)
2822{
2823 ida_free(&input_ida, minor);
2824}
2825EXPORT_SYMBOL(input_free_minor);
2826
2827static int __init input_init(void)
2828{
2829 int err;
2830
2831 err = class_register(&input_class);
2832 if (err) {
2833 pr_err("unable to register input_dev class\n");
2834 return err;
2835 }
2836
2837 err = input_proc_init();
2838 if (err)
2839 goto fail1;
2840
2841 err = register_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2842 INPUT_MAX_CHAR_DEVICES, "input");
2843 if (err) {
2844 pr_err("unable to register char major %d", INPUT_MAJOR);
2845 goto fail2;
2846 }
2847
2848 return 0;
2849
2850 fail2: input_proc_exit();
2851 fail1: class_unregister(&input_class);
2852 return err;
2853}
2854
2855static void __exit input_exit(void)
2856{
2857 input_proc_exit();
2858 unregister_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2859 INPUT_MAX_CHAR_DEVICES);
2860 class_unregister(&input_class);
2861}
2862
2863subsys_initcall(input_init);
2864module_exit(input_exit);