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