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