1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * The input core
4 *
5 * Copyright (c) 1999-2002 Vojtech Pavlik
6 */
7
8
9#define pr_fmt(fmt) KBUILD_BASENAME ": " fmt
10
11#include <linux/init.h>
12#include <linux/types.h>
13#include <linux/idr.h>
14#include <linux/input/mt.h>
15#include <linux/module.h>
16#include <linux/slab.h>
17#include <linux/random.h>
18#include <linux/major.h>
19#include <linux/proc_fs.h>
20#include <linux/sched.h>
21#include <linux/seq_file.h>
22#include <linux/pm.h>
23#include <linux/poll.h>
24#include <linux/device.h>
25#include <linux/kstrtox.h>
26#include <linux/mutex.h>
27#include <linux/rcupdate.h>
28#include "input-compat.h"
29#include "input-core-private.h"
30#include "input-poller.h"
31
32MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
33MODULE_DESCRIPTION("Input core");
34MODULE_LICENSE("GPL");
35
36#define INPUT_MAX_CHAR_DEVICES 1024
37#define INPUT_FIRST_DYNAMIC_DEV 256
38static DEFINE_IDA(input_ida);
39
40static LIST_HEAD(input_dev_list);
41static LIST_HEAD(input_handler_list);
42
43/*
44 * input_mutex protects access to both input_dev_list and input_handler_list.
45 * This also causes input_[un]register_device and input_[un]register_handler
46 * be mutually exclusive which simplifies locking in drivers implementing
47 * input handlers.
48 */
49static DEFINE_MUTEX(input_mutex);
50
51static const struct input_value input_value_sync = { EV_SYN, SYN_REPORT, 1 };
52
53static const unsigned int input_max_code[EV_CNT] = {
54 [EV_KEY] = KEY_MAX,
55 [EV_REL] = REL_MAX,
56 [EV_ABS] = ABS_MAX,
57 [EV_MSC] = MSC_MAX,
58 [EV_SW] = SW_MAX,
59 [EV_LED] = LED_MAX,
60 [EV_SND] = SND_MAX,
61 [EV_FF] = FF_MAX,
62};
63
64static inline int is_event_supported(unsigned int code,
65 unsigned long *bm, unsigned int max)
66{
67 return code <= max && test_bit(code, bm);
68}
69
70static int input_defuzz_abs_event(int value, int old_val, int fuzz)
71{
72 if (fuzz) {
73 if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
74 return old_val;
75
76 if (value > old_val - fuzz && value < old_val + fuzz)
77 return (old_val * 3 + value) / 4;
78
79 if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
80 return (old_val + value) / 2;
81 }
82
83 return value;
84}
85
86static void input_start_autorepeat(struct input_dev *dev, int code)
87{
88 if (test_bit(EV_REP, dev->evbit) &&
89 dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
90 dev->timer.function) {
91 dev->repeat_key = code;
92 mod_timer(timer: &dev->timer,
93 expires: jiffies + msecs_to_jiffies(m: dev->rep[REP_DELAY]));
94 }
95}
96
97static void input_stop_autorepeat(struct input_dev *dev)
98{
99 del_timer(timer: &dev->timer);
100}
101
102/*
103 * Pass event first through all filters and then, if event has not been
104 * filtered out, through all open handles. This function is called with
105 * dev->event_lock held and interrupts disabled.
106 */
107static unsigned int input_to_handler(struct input_handle *handle,
108 struct input_value *vals, unsigned int count)
109{
110 struct input_handler *handler = handle->handler;
111 struct input_value *end = vals;
112 struct input_value *v;
113
114 if (handler->filter) {
115 for (v = vals; v != vals + count; v++) {
116 if (handler->filter(handle, v->type, v->code, v->value))
117 continue;
118 if (end != v)
119 *end = *v;
120 end++;
121 }
122 count = end - vals;
123 }
124
125 if (!count)
126 return 0;
127
128 if (handler->events)
129 handler->events(handle, vals, count);
130 else if (handler->event)
131 for (v = vals; v != vals + count; v++)
132 handler->event(handle, v->type, v->code, v->value);
133
134 return count;
135}
136
137/*
138 * Pass values first through all filters and then, if event has not been
139 * filtered out, through all open handles. This function is called with
140 * dev->event_lock held and interrupts disabled.
141 */
142static void input_pass_values(struct input_dev *dev,
143 struct input_value *vals, unsigned int count)
144{
145 struct input_handle *handle;
146 struct input_value *v;
147
148 lockdep_assert_held(&dev->event_lock);
149
150 if (!count)
151 return;
152
153 rcu_read_lock();
154
155 handle = rcu_dereference(dev->grab);
156 if (handle) {
157 count = input_to_handler(handle, vals, count);
158 } else {
159 list_for_each_entry_rcu(handle, &dev->h_list, d_node)
160 if (handle->open) {
161 count = input_to_handler(handle, vals, count);
162 if (!count)
163 break;
164 }
165 }
166
167 rcu_read_unlock();
168
169 /* trigger auto repeat for key events */
170 if (test_bit(EV_REP, dev->evbit) && test_bit(EV_KEY, dev->evbit)) {
171 for (v = vals; v != vals + count; v++) {
172 if (v->type == EV_KEY && v->value != 2) {
173 if (v->value)
174 input_start_autorepeat(dev, code: v->code);
175 else
176 input_stop_autorepeat(dev);
177 }
178 }
179 }
180}
181
182#define INPUT_IGNORE_EVENT 0
183#define INPUT_PASS_TO_HANDLERS 1
184#define INPUT_PASS_TO_DEVICE 2
185#define INPUT_SLOT 4
186#define INPUT_FLUSH 8
187#define INPUT_PASS_TO_ALL (INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
188
189static int input_handle_abs_event(struct input_dev *dev,
190 unsigned int code, int *pval)
191{
192 struct input_mt *mt = dev->mt;
193 bool is_new_slot = false;
194 bool is_mt_event;
195 int *pold;
196
197 if (code == ABS_MT_SLOT) {
198 /*
199 * "Stage" the event; we'll flush it later, when we
200 * get actual touch data.
201 */
202 if (mt && *pval >= 0 && *pval < mt->num_slots)
203 mt->slot = *pval;
204
205 return INPUT_IGNORE_EVENT;
206 }
207
208 is_mt_event = input_is_mt_value(axis: code);
209
210 if (!is_mt_event) {
211 pold = &dev->absinfo[code].value;
212 } else if (mt) {
213 pold = &mt->slots[mt->slot].abs[code - ABS_MT_FIRST];
214 is_new_slot = mt->slot != dev->absinfo[ABS_MT_SLOT].value;
215 } else {
216 /*
217 * Bypass filtering for multi-touch events when
218 * not employing slots.
219 */
220 pold = NULL;
221 }
222
223 if (pold) {
224 *pval = input_defuzz_abs_event(value: *pval, old_val: *pold,
225 fuzz: dev->absinfo[code].fuzz);
226 if (*pold == *pval)
227 return INPUT_IGNORE_EVENT;
228
229 *pold = *pval;
230 }
231
232 /* Flush pending "slot" event */
233 if (is_new_slot) {
234 dev->absinfo[ABS_MT_SLOT].value = mt->slot;
235 return INPUT_PASS_TO_HANDLERS | INPUT_SLOT;
236 }
237
238 return INPUT_PASS_TO_HANDLERS;
239}
240
241static int input_get_disposition(struct input_dev *dev,
242 unsigned int type, unsigned int code, int *pval)
243{
244 int disposition = INPUT_IGNORE_EVENT;
245 int value = *pval;
246
247 /* filter-out events from inhibited devices */
248 if (dev->inhibited)
249 return INPUT_IGNORE_EVENT;
250
251 switch (type) {
252
253 case EV_SYN:
254 switch (code) {
255 case SYN_CONFIG:
256 disposition = INPUT_PASS_TO_ALL;
257 break;
258
259 case SYN_REPORT:
260 disposition = INPUT_PASS_TO_HANDLERS | INPUT_FLUSH;
261 break;
262 case SYN_MT_REPORT:
263 disposition = INPUT_PASS_TO_HANDLERS;
264 break;
265 }
266 break;
267
268 case EV_KEY:
269 if (is_event_supported(code, bm: dev->keybit, KEY_MAX)) {
270
271 /* auto-repeat bypasses state updates */
272 if (value == 2) {
273 disposition = INPUT_PASS_TO_HANDLERS;
274 break;
275 }
276
277 if (!!test_bit(code, dev->key) != !!value) {
278
279 __change_bit(code, dev->key);
280 disposition = INPUT_PASS_TO_HANDLERS;
281 }
282 }
283 break;
284
285 case EV_SW:
286 if (is_event_supported(code, bm: dev->swbit, SW_MAX) &&
287 !!test_bit(code, dev->sw) != !!value) {
288
289 __change_bit(code, dev->sw);
290 disposition = INPUT_PASS_TO_HANDLERS;
291 }
292 break;
293
294 case EV_ABS:
295 if (is_event_supported(code, bm: dev->absbit, ABS_MAX))
296 disposition = input_handle_abs_event(dev, code, pval: &value);
297
298 break;
299
300 case EV_REL:
301 if (is_event_supported(code, bm: dev->relbit, REL_MAX) && value)
302 disposition = INPUT_PASS_TO_HANDLERS;
303
304 break;
305
306 case EV_MSC:
307 if (is_event_supported(code, bm: dev->mscbit, MSC_MAX))
308 disposition = INPUT_PASS_TO_ALL;
309
310 break;
311
312 case EV_LED:
313 if (is_event_supported(code, bm: dev->ledbit, LED_MAX) &&
314 !!test_bit(code, dev->led) != !!value) {
315
316 __change_bit(code, dev->led);
317 disposition = INPUT_PASS_TO_ALL;
318 }
319 break;
320
321 case EV_SND:
322 if (is_event_supported(code, bm: dev->sndbit, SND_MAX)) {
323
324 if (!!test_bit(code, dev->snd) != !!value)
325 __change_bit(code, dev->snd);
326 disposition = INPUT_PASS_TO_ALL;
327 }
328 break;
329
330 case EV_REP:
331 if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
332 dev->rep[code] = value;
333 disposition = INPUT_PASS_TO_ALL;
334 }
335 break;
336
337 case EV_FF:
338 if (value >= 0)
339 disposition = INPUT_PASS_TO_ALL;
340 break;
341
342 case EV_PWR:
343 disposition = INPUT_PASS_TO_ALL;
344 break;
345 }
346
347 *pval = value;
348 return disposition;
349}
350
351static void input_event_dispose(struct input_dev *dev, int disposition,
352 unsigned int type, unsigned int code, int value)
353{
354 if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
355 dev->event(dev, type, code, value);
356
357 if (!dev->vals)
358 return;
359
360 if (disposition & INPUT_PASS_TO_HANDLERS) {
361 struct input_value *v;
362
363 if (disposition & INPUT_SLOT) {
364 v = &dev->vals[dev->num_vals++];
365 v->type = EV_ABS;
366 v->code = ABS_MT_SLOT;
367 v->value = dev->mt->slot;
368 }
369
370 v = &dev->vals[dev->num_vals++];
371 v->type = type;
372 v->code = code;
373 v->value = value;
374 }
375
376 if (disposition & INPUT_FLUSH) {
377 if (dev->num_vals >= 2)
378 input_pass_values(dev, vals: dev->vals, count: dev->num_vals);
379 dev->num_vals = 0;
380 /*
381 * Reset the timestamp on flush so we won't end up
382 * with a stale one. Note we only need to reset the
383 * monolithic one as we use its presence when deciding
384 * whether to generate a synthetic timestamp.
385 */
386 dev->timestamp[INPUT_CLK_MONO] = ktime_set(secs: 0, nsecs: 0);
387 } else if (dev->num_vals >= dev->max_vals - 2) {
388 dev->vals[dev->num_vals++] = input_value_sync;
389 input_pass_values(dev, vals: dev->vals, count: dev->num_vals);
390 dev->num_vals = 0;
391 }
392}
393
394void input_handle_event(struct input_dev *dev,
395 unsigned int type, unsigned int code, int value)
396{
397 int disposition;
398
399 lockdep_assert_held(&dev->event_lock);
400
401 disposition = input_get_disposition(dev, type, code, pval: &value);
402 if (disposition != INPUT_IGNORE_EVENT) {
403 if (type != EV_SYN)
404 add_input_randomness(type, code, value);
405
406 input_event_dispose(dev, disposition, type, code, value);
407 }
408}
409
410/**
411 * input_event() - report new input event
412 * @dev: device that generated the event
413 * @type: type of the event
414 * @code: event code
415 * @value: value of the event
416 *
417 * This function should be used by drivers implementing various input
418 * devices to report input events. See also input_inject_event().
419 *
420 * NOTE: input_event() may be safely used right after input device was
421 * allocated with input_allocate_device(), even before it is registered
422 * with input_register_device(), but the event will not reach any of the
423 * input handlers. Such early invocation of input_event() may be used
424 * to 'seed' initial state of a switch or initial position of absolute
425 * axis, etc.
426 */
427void input_event(struct input_dev *dev,
428 unsigned int type, unsigned int code, int value)
429{
430 unsigned long flags;
431
432 if (is_event_supported(code: type, bm: dev->evbit, EV_MAX)) {
433
434 spin_lock_irqsave(&dev->event_lock, flags);
435 input_handle_event(dev, type, code, value);
436 spin_unlock_irqrestore(lock: &dev->event_lock, flags);
437 }
438}
439EXPORT_SYMBOL(input_event);
440
441/**
442 * input_inject_event() - send input event from input handler
443 * @handle: input handle to send event through
444 * @type: type of the event
445 * @code: event code
446 * @value: value of the event
447 *
448 * Similar to input_event() but will ignore event if device is
449 * "grabbed" and handle injecting event is not the one that owns
450 * the device.
451 */
452void input_inject_event(struct input_handle *handle,
453 unsigned int type, unsigned int code, int value)
454{
455 struct input_dev *dev = handle->dev;
456 struct input_handle *grab;
457 unsigned long flags;
458
459 if (is_event_supported(code: type, bm: dev->evbit, EV_MAX)) {
460 spin_lock_irqsave(&dev->event_lock, flags);
461
462 rcu_read_lock();
463 grab = rcu_dereference(dev->grab);
464 if (!grab || grab == handle)
465 input_handle_event(dev, type, code, value);
466 rcu_read_unlock();
467
468 spin_unlock_irqrestore(lock: &dev->event_lock, flags);
469 }
470}
471EXPORT_SYMBOL(input_inject_event);
472
473/**
474 * input_alloc_absinfo - allocates array of input_absinfo structs
475 * @dev: the input device emitting absolute events
476 *
477 * If the absinfo struct the caller asked for is already allocated, this
478 * functions will not do anything.
479 */
480void input_alloc_absinfo(struct input_dev *dev)
481{
482 if (dev->absinfo)
483 return;
484
485 dev->absinfo = kcalloc(ABS_CNT, size: sizeof(*dev->absinfo), GFP_KERNEL);
486 if (!dev->absinfo) {
487 dev_err(dev->dev.parent ?: &dev->dev,
488 "%s: unable to allocate memory\n", __func__);
489 /*
490 * We will handle this allocation failure in
491 * input_register_device() when we refuse to register input
492 * device with ABS bits but without absinfo.
493 */
494 }
495}
496EXPORT_SYMBOL(input_alloc_absinfo);
497
498void input_set_abs_params(struct input_dev *dev, unsigned int axis,
499 int min, int max, int fuzz, int flat)
500{
501 struct input_absinfo *absinfo;
502
503 __set_bit(EV_ABS, dev->evbit);
504 __set_bit(axis, dev->absbit);
505
506 input_alloc_absinfo(dev);
507 if (!dev->absinfo)
508 return;
509
510 absinfo = &dev->absinfo[axis];
511 absinfo->minimum = min;
512 absinfo->maximum = max;
513 absinfo->fuzz = fuzz;
514 absinfo->flat = flat;
515}
516EXPORT_SYMBOL(input_set_abs_params);
517
518/**
519 * input_copy_abs - Copy absinfo from one input_dev to another
520 * @dst: Destination input device to copy the abs settings to
521 * @dst_axis: ABS_* value selecting the destination axis
522 * @src: Source input device to copy the abs settings from
523 * @src_axis: ABS_* value selecting the source axis
524 *
525 * Set absinfo for the selected destination axis by copying it from
526 * the specified source input device's source axis.
527 * This is useful to e.g. setup a pen/stylus input-device for combined
528 * touchscreen/pen hardware where the pen uses the same coordinates as
529 * the touchscreen.
530 */
531void input_copy_abs(struct input_dev *dst, unsigned int dst_axis,
532 const struct input_dev *src, unsigned int src_axis)
533{
534 /* src must have EV_ABS and src_axis set */
535 if (WARN_ON(!(test_bit(EV_ABS, src->evbit) &&
536 test_bit(src_axis, src->absbit))))
537 return;
538
539 /*
540 * input_alloc_absinfo() may have failed for the source. Our caller is
541 * expected to catch this when registering the input devices, which may
542 * happen after the input_copy_abs() call.
543 */
544 if (!src->absinfo)
545 return;
546
547 input_set_capability(dev: dst, EV_ABS, code: dst_axis);
548 if (!dst->absinfo)
549 return;
550
551 dst->absinfo[dst_axis] = src->absinfo[src_axis];
552}
553EXPORT_SYMBOL(input_copy_abs);
554
555/**
556 * input_grab_device - grabs device for exclusive use
557 * @handle: input handle that wants to own the device
558 *
559 * When a device is grabbed by an input handle all events generated by
560 * the device are delivered only to this handle. Also events injected
561 * by other input handles are ignored while device is grabbed.
562 */
563int input_grab_device(struct input_handle *handle)
564{
565 struct input_dev *dev = handle->dev;
566 int retval;
567
568 retval = mutex_lock_interruptible(&dev->mutex);
569 if (retval)
570 return retval;
571
572 if (dev->grab) {
573 retval = -EBUSY;
574 goto out;
575 }
576
577 rcu_assign_pointer(dev->grab, handle);
578
579 out:
580 mutex_unlock(lock: &dev->mutex);
581 return retval;
582}
583EXPORT_SYMBOL(input_grab_device);
584
585static void __input_release_device(struct input_handle *handle)
586{
587 struct input_dev *dev = handle->dev;
588 struct input_handle *grabber;
589
590 grabber = rcu_dereference_protected(dev->grab,
591 lockdep_is_held(&dev->mutex));
592 if (grabber == handle) {
593 rcu_assign_pointer(dev->grab, NULL);
594 /* Make sure input_pass_values() notices that grab is gone */
595 synchronize_rcu();
596
597 list_for_each_entry(handle, &dev->h_list, d_node)
598 if (handle->open && handle->handler->start)
599 handle->handler->start(handle);
600 }
601}
602
603/**
604 * input_release_device - release previously grabbed device
605 * @handle: input handle that owns the device
606 *
607 * Releases previously grabbed device so that other input handles can
608 * start receiving input events. Upon release all handlers attached
609 * to the device have their start() method called so they have a change
610 * to synchronize device state with the rest of the system.
611 */
612void input_release_device(struct input_handle *handle)
613{
614 struct input_dev *dev = handle->dev;
615
616 mutex_lock(&dev->mutex);
617 __input_release_device(handle);
618 mutex_unlock(lock: &dev->mutex);
619}
620EXPORT_SYMBOL(input_release_device);
621
622/**
623 * input_open_device - open input device
624 * @handle: handle through which device is being accessed
625 *
626 * This function should be called by input handlers when they
627 * want to start receive events from given input device.
628 */
629int input_open_device(struct input_handle *handle)
630{
631 struct input_dev *dev = handle->dev;
632 int retval;
633
634 retval = mutex_lock_interruptible(&dev->mutex);
635 if (retval)
636 return retval;
637
638 if (dev->going_away) {
639 retval = -ENODEV;
640 goto out;
641 }
642
643 handle->open++;
644
645 if (dev->users++ || dev->inhibited) {
646 /*
647 * Device is already opened and/or inhibited,
648 * so we can exit immediately and report success.
649 */
650 goto out;
651 }
652
653 if (dev->open) {
654 retval = dev->open(dev);
655 if (retval) {
656 dev->users--;
657 handle->open--;
658 /*
659 * Make sure we are not delivering any more events
660 * through this handle
661 */
662 synchronize_rcu();
663 goto out;
664 }
665 }
666
667 if (dev->poller)
668 input_dev_poller_start(poller: dev->poller);
669
670 out:
671 mutex_unlock(lock: &dev->mutex);
672 return retval;
673}
674EXPORT_SYMBOL(input_open_device);
675
676int input_flush_device(struct input_handle *handle, struct file *file)
677{
678 struct input_dev *dev = handle->dev;
679 int retval;
680
681 retval = mutex_lock_interruptible(&dev->mutex);
682 if (retval)
683 return retval;
684
685 if (dev->flush)
686 retval = dev->flush(dev, file);
687
688 mutex_unlock(lock: &dev->mutex);
689 return retval;
690}
691EXPORT_SYMBOL(input_flush_device);
692
693/**
694 * input_close_device - close input device
695 * @handle: handle through which device is being accessed
696 *
697 * This function should be called by input handlers when they
698 * want to stop receive events from given input device.
699 */
700void input_close_device(struct input_handle *handle)
701{
702 struct input_dev *dev = handle->dev;
703
704 mutex_lock(&dev->mutex);
705
706 __input_release_device(handle);
707
708 if (!--dev->users && !dev->inhibited) {
709 if (dev->poller)
710 input_dev_poller_stop(poller: dev->poller);
711 if (dev->close)
712 dev->close(dev);
713 }
714
715 if (!--handle->open) {
716 /*
717 * synchronize_rcu() makes sure that input_pass_values()
718 * completed and that no more input events are delivered
719 * through this handle
720 */
721 synchronize_rcu();
722 }
723
724 mutex_unlock(lock: &dev->mutex);
725}
726EXPORT_SYMBOL(input_close_device);
727
728/*
729 * Simulate keyup events for all keys that are marked as pressed.
730 * The function must be called with dev->event_lock held.
731 */
732static bool input_dev_release_keys(struct input_dev *dev)
733{
734 bool need_sync = false;
735 int code;
736
737 lockdep_assert_held(&dev->event_lock);
738
739 if (is_event_supported(EV_KEY, bm: dev->evbit, EV_MAX)) {
740 for_each_set_bit(code, dev->key, KEY_CNT) {
741 input_handle_event(dev, EV_KEY, code, value: 0);
742 need_sync = true;
743 }
744 }
745
746 return need_sync;
747}
748
749/*
750 * Prepare device for unregistering
751 */
752static void input_disconnect_device(struct input_dev *dev)
753{
754 struct input_handle *handle;
755
756 /*
757 * Mark device as going away. Note that we take dev->mutex here
758 * not to protect access to dev->going_away but rather to ensure
759 * that there are no threads in the middle of input_open_device()
760 */
761 mutex_lock(&dev->mutex);
762 dev->going_away = true;
763 mutex_unlock(lock: &dev->mutex);
764
765 spin_lock_irq(lock: &dev->event_lock);
766
767 /*
768 * Simulate keyup events for all pressed keys so that handlers
769 * are not left with "stuck" keys. The driver may continue
770 * generate events even after we done here but they will not
771 * reach any handlers.
772 */
773 if (input_dev_release_keys(dev))
774 input_handle_event(dev, EV_SYN, SYN_REPORT, value: 1);
775
776 list_for_each_entry(handle, &dev->h_list, d_node)
777 handle->open = 0;
778
779 spin_unlock_irq(lock: &dev->event_lock);
780}
781
782/**
783 * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
784 * @ke: keymap entry containing scancode to be converted.
785 * @scancode: pointer to the location where converted scancode should
786 * be stored.
787 *
788 * This function is used to convert scancode stored in &struct keymap_entry
789 * into scalar form understood by legacy keymap handling methods. These
790 * methods expect scancodes to be represented as 'unsigned int'.
791 */
792int input_scancode_to_scalar(const struct input_keymap_entry *ke,
793 unsigned int *scancode)
794{
795 switch (ke->len) {
796 case 1:
797 *scancode = *((u8 *)ke->scancode);
798 break;
799
800 case 2:
801 *scancode = *((u16 *)ke->scancode);
802 break;
803
804 case 4:
805 *scancode = *((u32 *)ke->scancode);
806 break;
807
808 default:
809 return -EINVAL;
810 }
811
812 return 0;
813}
814EXPORT_SYMBOL(input_scancode_to_scalar);
815
816/*
817 * Those routines handle the default case where no [gs]etkeycode() is
818 * defined. In this case, an array indexed by the scancode is used.
819 */
820
821static unsigned int input_fetch_keycode(struct input_dev *dev,
822 unsigned int index)
823{
824 switch (dev->keycodesize) {
825 case 1:
826 return ((u8 *)dev->keycode)[index];
827
828 case 2:
829 return ((u16 *)dev->keycode)[index];
830
831 default:
832 return ((u32 *)dev->keycode)[index];
833 }
834}
835
836static int input_default_getkeycode(struct input_dev *dev,
837 struct input_keymap_entry *ke)
838{
839 unsigned int index;
840 int error;
841
842 if (!dev->keycodesize)
843 return -EINVAL;
844
845 if (ke->flags & INPUT_KEYMAP_BY_INDEX)
846 index = ke->index;
847 else {
848 error = input_scancode_to_scalar(ke, &index);
849 if (error)
850 return error;
851 }
852
853 if (index >= dev->keycodemax)
854 return -EINVAL;
855
856 ke->keycode = input_fetch_keycode(dev, index);
857 ke->index = index;
858 ke->len = sizeof(index);
859 memcpy(ke->scancode, &index, sizeof(index));
860
861 return 0;
862}
863
864static int input_default_setkeycode(struct input_dev *dev,
865 const struct input_keymap_entry *ke,
866 unsigned int *old_keycode)
867{
868 unsigned int index;
869 int error;
870 int i;
871
872 if (!dev->keycodesize)
873 return -EINVAL;
874
875 if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
876 index = ke->index;
877 } else {
878 error = input_scancode_to_scalar(ke, &index);
879 if (error)
880 return error;
881 }
882
883 if (index >= dev->keycodemax)
884 return -EINVAL;
885
886 if (dev->keycodesize < sizeof(ke->keycode) &&
887 (ke->keycode >> (dev->keycodesize * 8)))
888 return -EINVAL;
889
890 switch (dev->keycodesize) {
891 case 1: {
892 u8 *k = (u8 *)dev->keycode;
893 *old_keycode = k[index];
894 k[index] = ke->keycode;
895 break;
896 }
897 case 2: {
898 u16 *k = (u16 *)dev->keycode;
899 *old_keycode = k[index];
900 k[index] = ke->keycode;
901 break;
902 }
903 default: {
904 u32 *k = (u32 *)dev->keycode;
905 *old_keycode = k[index];
906 k[index] = ke->keycode;
907 break;
908 }
909 }
910
911 if (*old_keycode <= KEY_MAX) {
912 __clear_bit(*old_keycode, dev->keybit);
913 for (i = 0; i < dev->keycodemax; i++) {
914 if (input_fetch_keycode(dev, index: i) == *old_keycode) {
915 __set_bit(*old_keycode, dev->keybit);
916 /* Setting the bit twice is useless, so break */
917 break;
918 }
919 }
920 }
921
922 __set_bit(ke->keycode, dev->keybit);
923 return 0;
924}
925
926/**
927 * input_get_keycode - retrieve keycode currently mapped to a given scancode
928 * @dev: input device which keymap is being queried
929 * @ke: keymap entry
930 *
931 * This function should be called by anyone interested in retrieving current
932 * keymap. Presently evdev handlers use it.
933 */
934int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
935{
936 unsigned long flags;
937 int retval;
938
939 spin_lock_irqsave(&dev->event_lock, flags);
940 retval = dev->getkeycode(dev, ke);
941 spin_unlock_irqrestore(lock: &dev->event_lock, flags);
942
943 return retval;
944}
945EXPORT_SYMBOL(input_get_keycode);
946
947/**
948 * input_set_keycode - attribute a keycode to a given scancode
949 * @dev: input device which keymap is being updated
950 * @ke: new keymap entry
951 *
952 * This function should be called by anyone needing to update current
953 * keymap. Presently keyboard and evdev handlers use it.
954 */
955int input_set_keycode(struct input_dev *dev,
956 const struct input_keymap_entry *ke)
957{
958 unsigned long flags;
959 unsigned int old_keycode;
960 int retval;
961
962 if (ke->keycode > KEY_MAX)
963 return -EINVAL;
964
965 spin_lock_irqsave(&dev->event_lock, flags);
966
967 retval = dev->setkeycode(dev, ke, &old_keycode);
968 if (retval)
969 goto out;
970
971 /* Make sure KEY_RESERVED did not get enabled. */
972 __clear_bit(KEY_RESERVED, dev->keybit);
973
974 /*
975 * Simulate keyup event if keycode is not present
976 * in the keymap anymore
977 */
978 if (old_keycode > KEY_MAX) {
979 dev_warn(dev->dev.parent ?: &dev->dev,
980 "%s: got too big old keycode %#x\n",
981 __func__, old_keycode);
982 } else if (test_bit(EV_KEY, dev->evbit) &&
983 !is_event_supported(code: old_keycode, bm: dev->keybit, KEY_MAX) &&
984 __test_and_clear_bit(old_keycode, dev->key)) {
985 /*
986 * We have to use input_event_dispose() here directly instead
987 * of input_handle_event() because the key we want to release
988 * here is considered no longer supported by the device and
989 * input_handle_event() will ignore it.
990 */
991 input_event_dispose(dev, INPUT_PASS_TO_HANDLERS,
992 EV_KEY, code: old_keycode, value: 0);
993 input_event_dispose(dev, INPUT_PASS_TO_HANDLERS | INPUT_FLUSH,
994 EV_SYN, SYN_REPORT, value: 1);
995 }
996
997 out:
998 spin_unlock_irqrestore(lock: &dev->event_lock, flags);
999
1000 return retval;
1001}
1002EXPORT_SYMBOL(input_set_keycode);
1003
1004bool input_match_device_id(const struct input_dev *dev,
1005 const struct input_device_id *id)
1006{
1007 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
1008 if (id->bustype != dev->id.bustype)
1009 return false;
1010
1011 if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
1012 if (id->vendor != dev->id.vendor)
1013 return false;
1014
1015 if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
1016 if (id->product != dev->id.product)
1017 return false;
1018
1019 if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
1020 if (id->version != dev->id.version)
1021 return false;
1022
1023 if (!bitmap_subset(src1: id->evbit, src2: dev->evbit, EV_MAX) ||
1024 !bitmap_subset(src1: id->keybit, src2: dev->keybit, KEY_MAX) ||
1025 !bitmap_subset(src1: id->relbit, src2: dev->relbit, REL_MAX) ||
1026 !bitmap_subset(src1: id->absbit, src2: dev->absbit, ABS_MAX) ||
1027 !bitmap_subset(src1: id->mscbit, src2: dev->mscbit, MSC_MAX) ||
1028 !bitmap_subset(src1: id->ledbit, src2: dev->ledbit, LED_MAX) ||
1029 !bitmap_subset(src1: id->sndbit, src2: dev->sndbit, SND_MAX) ||
1030 !bitmap_subset(src1: id->ffbit, src2: dev->ffbit, FF_MAX) ||
1031 !bitmap_subset(src1: id->swbit, src2: dev->swbit, SW_MAX) ||
1032 !bitmap_subset(src1: id->propbit, src2: dev->propbit, INPUT_PROP_MAX)) {
1033 return false;
1034 }
1035
1036 return true;
1037}
1038EXPORT_SYMBOL(input_match_device_id);
1039
1040static const struct input_device_id *input_match_device(struct input_handler *handler,
1041 struct input_dev *dev)
1042{
1043 const struct input_device_id *id;
1044
1045 for (id = handler->id_table; id->flags || id->driver_info; id++) {
1046 if (input_match_device_id(dev, id) &&
1047 (!handler->match || handler->match(handler, dev))) {
1048 return id;
1049 }
1050 }
1051
1052 return NULL;
1053}
1054
1055static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
1056{
1057 const struct input_device_id *id;
1058 int error;
1059
1060 id = input_match_device(handler, dev);
1061 if (!id)
1062 return -ENODEV;
1063
1064 error = handler->connect(handler, dev, id);
1065 if (error && error != -ENODEV)
1066 pr_err("failed to attach handler %s to device %s, error: %d\n",
1067 handler->name, kobject_name(&dev->dev.kobj), error);
1068
1069 return error;
1070}
1071
1072#ifdef CONFIG_COMPAT
1073
1074static int input_bits_to_string(char *buf, int buf_size,
1075 unsigned long bits, bool skip_empty)
1076{
1077 int len = 0;
1078
1079 if (in_compat_syscall()) {
1080 u32 dword = bits >> 32;
1081 if (dword || !skip_empty)
1082 len += snprintf(buf, size: buf_size, fmt: "%x ", dword);
1083
1084 dword = bits & 0xffffffffUL;
1085 if (dword || !skip_empty || len)
1086 len += snprintf(buf: buf + len, max(buf_size - len, 0),
1087 fmt: "%x", dword);
1088 } else {
1089 if (bits || !skip_empty)
1090 len += snprintf(buf, size: buf_size, fmt: "%lx", bits);
1091 }
1092
1093 return len;
1094}
1095
1096#else /* !CONFIG_COMPAT */
1097
1098static int input_bits_to_string(char *buf, int buf_size,
1099 unsigned long bits, bool skip_empty)
1100{
1101 return bits || !skip_empty ?
1102 snprintf(buf, buf_size, "%lx", bits) : 0;
1103}
1104
1105#endif
1106
1107#ifdef CONFIG_PROC_FS
1108
1109static struct proc_dir_entry *proc_bus_input_dir;
1110static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
1111static int input_devices_state;
1112
1113static inline void input_wakeup_procfs_readers(void)
1114{
1115 input_devices_state++;
1116 wake_up(&input_devices_poll_wait);
1117}
1118
1119static __poll_t input_proc_devices_poll(struct file *file, poll_table *wait)
1120{
1121 poll_wait(filp: file, wait_address: &input_devices_poll_wait, p: wait);
1122 if (file->f_version != input_devices_state) {
1123 file->f_version = input_devices_state;
1124 return EPOLLIN | EPOLLRDNORM;
1125 }
1126
1127 return 0;
1128}
1129
1130union input_seq_state {
1131 struct {
1132 unsigned short pos;
1133 bool mutex_acquired;
1134 };
1135 void *p;
1136};
1137
1138static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
1139{
1140 union input_seq_state *state = (union input_seq_state *)&seq->private;
1141 int error;
1142
1143 /* We need to fit into seq->private pointer */
1144 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1145
1146 error = mutex_lock_interruptible(&input_mutex);
1147 if (error) {
1148 state->mutex_acquired = false;
1149 return ERR_PTR(error);
1150 }
1151
1152 state->mutex_acquired = true;
1153
1154 return seq_list_start(head: &input_dev_list, pos: *pos);
1155}
1156
1157static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1158{
1159 return seq_list_next(v, head: &input_dev_list, ppos: pos);
1160}
1161
1162static void input_seq_stop(struct seq_file *seq, void *v)
1163{
1164 union input_seq_state *state = (union input_seq_state *)&seq->private;
1165
1166 if (state->mutex_acquired)
1167 mutex_unlock(lock: &input_mutex);
1168}
1169
1170static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
1171 unsigned long *bitmap, int max)
1172{
1173 int i;
1174 bool skip_empty = true;
1175 char buf[18];
1176
1177 seq_printf(m: seq, fmt: "B: %s=", name);
1178
1179 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1180 if (input_bits_to_string(buf, buf_size: sizeof(buf),
1181 bits: bitmap[i], skip_empty)) {
1182 skip_empty = false;
1183 seq_printf(m: seq, fmt: "%s%s", buf, i > 0 ? " " : "");
1184 }
1185 }
1186
1187 /*
1188 * If no output was produced print a single 0.
1189 */
1190 if (skip_empty)
1191 seq_putc(m: seq, c: '0');
1192
1193 seq_putc(m: seq, c: '\n');
1194}
1195
1196static int input_devices_seq_show(struct seq_file *seq, void *v)
1197{
1198 struct input_dev *dev = container_of(v, struct input_dev, node);
1199 const char *path = kobject_get_path(kobj: &dev->dev.kobj, GFP_KERNEL);
1200 struct input_handle *handle;
1201
1202 seq_printf(m: seq, fmt: "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
1203 dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
1204
1205 seq_printf(m: seq, fmt: "N: Name=\"%s\"\n", dev->name ? dev->name : "");
1206 seq_printf(m: seq, fmt: "P: Phys=%s\n", dev->phys ? dev->phys : "");
1207 seq_printf(m: seq, fmt: "S: Sysfs=%s\n", path ? path : "");
1208 seq_printf(m: seq, fmt: "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1209 seq_puts(m: seq, s: "H: Handlers=");
1210
1211 list_for_each_entry(handle, &dev->h_list, d_node)
1212 seq_printf(m: seq, fmt: "%s ", handle->name);
1213 seq_putc(m: seq, c: '\n');
1214
1215 input_seq_print_bitmap(seq, name: "PROP", bitmap: dev->propbit, INPUT_PROP_MAX);
1216
1217 input_seq_print_bitmap(seq, name: "EV", bitmap: dev->evbit, EV_MAX);
1218 if (test_bit(EV_KEY, dev->evbit))
1219 input_seq_print_bitmap(seq, name: "KEY", bitmap: dev->keybit, KEY_MAX);
1220 if (test_bit(EV_REL, dev->evbit))
1221 input_seq_print_bitmap(seq, name: "REL", bitmap: dev->relbit, REL_MAX);
1222 if (test_bit(EV_ABS, dev->evbit))
1223 input_seq_print_bitmap(seq, name: "ABS", bitmap: dev->absbit, ABS_MAX);
1224 if (test_bit(EV_MSC, dev->evbit))
1225 input_seq_print_bitmap(seq, name: "MSC", bitmap: dev->mscbit, MSC_MAX);
1226 if (test_bit(EV_LED, dev->evbit))
1227 input_seq_print_bitmap(seq, name: "LED", bitmap: dev->ledbit, LED_MAX);
1228 if (test_bit(EV_SND, dev->evbit))
1229 input_seq_print_bitmap(seq, name: "SND", bitmap: dev->sndbit, SND_MAX);
1230 if (test_bit(EV_FF, dev->evbit))
1231 input_seq_print_bitmap(seq, name: "FF", bitmap: dev->ffbit, FF_MAX);
1232 if (test_bit(EV_SW, dev->evbit))
1233 input_seq_print_bitmap(seq, name: "SW", bitmap: dev->swbit, SW_MAX);
1234
1235 seq_putc(m: seq, c: '\n');
1236
1237 kfree(objp: path);
1238 return 0;
1239}
1240
1241static const struct seq_operations input_devices_seq_ops = {
1242 .start = input_devices_seq_start,
1243 .next = input_devices_seq_next,
1244 .stop = input_seq_stop,
1245 .show = input_devices_seq_show,
1246};
1247
1248static int input_proc_devices_open(struct inode *inode, struct file *file)
1249{
1250 return seq_open(file, &input_devices_seq_ops);
1251}
1252
1253static const struct proc_ops input_devices_proc_ops = {
1254 .proc_open = input_proc_devices_open,
1255 .proc_poll = input_proc_devices_poll,
1256 .proc_read = seq_read,
1257 .proc_lseek = seq_lseek,
1258 .proc_release = seq_release,
1259};
1260
1261static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
1262{
1263 union input_seq_state *state = (union input_seq_state *)&seq->private;
1264 int error;
1265
1266 /* We need to fit into seq->private pointer */
1267 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1268
1269 error = mutex_lock_interruptible(&input_mutex);
1270 if (error) {
1271 state->mutex_acquired = false;
1272 return ERR_PTR(error);
1273 }
1274
1275 state->mutex_acquired = true;
1276 state->pos = *pos;
1277
1278 return seq_list_start(head: &input_handler_list, pos: *pos);
1279}
1280
1281static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1282{
1283 union input_seq_state *state = (union input_seq_state *)&seq->private;
1284
1285 state->pos = *pos + 1;
1286 return seq_list_next(v, head: &input_handler_list, ppos: pos);
1287}
1288
1289static int input_handlers_seq_show(struct seq_file *seq, void *v)
1290{
1291 struct input_handler *handler = container_of(v, struct input_handler, node);
1292 union input_seq_state *state = (union input_seq_state *)&seq->private;
1293
1294 seq_printf(m: seq, fmt: "N: Number=%u Name=%s", state->pos, handler->name);
1295 if (handler->filter)
1296 seq_puts(m: seq, s: " (filter)");
1297 if (handler->legacy_minors)
1298 seq_printf(m: seq, fmt: " Minor=%d", handler->minor);
1299 seq_putc(m: seq, c: '\n');
1300
1301 return 0;
1302}
1303
1304static const struct seq_operations input_handlers_seq_ops = {
1305 .start = input_handlers_seq_start,
1306 .next = input_handlers_seq_next,
1307 .stop = input_seq_stop,
1308 .show = input_handlers_seq_show,
1309};
1310
1311static int input_proc_handlers_open(struct inode *inode, struct file *file)
1312{
1313 return seq_open(file, &input_handlers_seq_ops);
1314}
1315
1316static const struct proc_ops input_handlers_proc_ops = {
1317 .proc_open = input_proc_handlers_open,
1318 .proc_read = seq_read,
1319 .proc_lseek = seq_lseek,
1320 .proc_release = seq_release,
1321};
1322
1323static int __init input_proc_init(void)
1324{
1325 struct proc_dir_entry *entry;
1326
1327 proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1328 if (!proc_bus_input_dir)
1329 return -ENOMEM;
1330
1331 entry = proc_create(name: "devices", mode: 0, parent: proc_bus_input_dir,
1332 proc_ops: &input_devices_proc_ops);
1333 if (!entry)
1334 goto fail1;
1335
1336 entry = proc_create(name: "handlers", mode: 0, parent: proc_bus_input_dir,
1337 proc_ops: &input_handlers_proc_ops);
1338 if (!entry)
1339 goto fail2;
1340
1341 return 0;
1342
1343 fail2: remove_proc_entry("devices", proc_bus_input_dir);
1344 fail1: remove_proc_entry("bus/input", NULL);
1345 return -ENOMEM;
1346}
1347
1348static void input_proc_exit(void)
1349{
1350 remove_proc_entry("devices", proc_bus_input_dir);
1351 remove_proc_entry("handlers", proc_bus_input_dir);
1352 remove_proc_entry("bus/input", NULL);
1353}
1354
1355#else /* !CONFIG_PROC_FS */
1356static inline void input_wakeup_procfs_readers(void) { }
1357static inline int input_proc_init(void) { return 0; }
1358static inline void input_proc_exit(void) { }
1359#endif
1360
1361#define INPUT_DEV_STRING_ATTR_SHOW(name) \
1362static ssize_t input_dev_show_##name(struct device *dev, \
1363 struct device_attribute *attr, \
1364 char *buf) \
1365{ \
1366 struct input_dev *input_dev = to_input_dev(dev); \
1367 \
1368 return sysfs_emit(buf, "%s\n", \
1369 input_dev->name ? input_dev->name : ""); \
1370} \
1371static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1372
1373INPUT_DEV_STRING_ATTR_SHOW(name);
1374INPUT_DEV_STRING_ATTR_SHOW(phys);
1375INPUT_DEV_STRING_ATTR_SHOW(uniq);
1376
1377static int input_print_modalias_bits(char *buf, int size,
1378 char name, const unsigned long *bm,
1379 unsigned int min_bit, unsigned int max_bit)
1380{
1381 int len = 0, i;
1382
1383 len += snprintf(buf, max(size, 0), fmt: "%c", name);
1384 for (i = min_bit; i < max_bit; i++)
1385 if (bm[BIT_WORD(i)] & BIT_MASK(i))
1386 len += snprintf(buf: buf + len, max(size - len, 0), fmt: "%X,", i);
1387 return len;
1388}
1389
1390static int input_print_modalias(char *buf, int size, const struct input_dev *id,
1391 int add_cr)
1392{
1393 int len;
1394
1395 len = snprintf(buf, max(size, 0),
1396 fmt: "input:b%04Xv%04Xp%04Xe%04X-",
1397 id->id.bustype, id->id.vendor,
1398 id->id.product, id->id.version);
1399
1400 len += input_print_modalias_bits(buf: buf + len, size: size - len,
1401 name: 'e', bm: id->evbit, min_bit: 0, EV_MAX);
1402 len += input_print_modalias_bits(buf: buf + len, size: size - len,
1403 name: 'k', bm: id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1404 len += input_print_modalias_bits(buf: buf + len, size: size - len,
1405 name: 'r', bm: id->relbit, min_bit: 0, REL_MAX);
1406 len += input_print_modalias_bits(buf: buf + len, size: size - len,
1407 name: 'a', bm: id->absbit, min_bit: 0, ABS_MAX);
1408 len += input_print_modalias_bits(buf: buf + len, size: size - len,
1409 name: 'm', bm: id->mscbit, min_bit: 0, MSC_MAX);
1410 len += input_print_modalias_bits(buf: buf + len, size: size - len,
1411 name: 'l', bm: id->ledbit, min_bit: 0, LED_MAX);
1412 len += input_print_modalias_bits(buf: buf + len, size: size - len,
1413 name: 's', bm: id->sndbit, min_bit: 0, SND_MAX);
1414 len += input_print_modalias_bits(buf: buf + len, size: size - len,
1415 name: 'f', bm: id->ffbit, min_bit: 0, FF_MAX);
1416 len += input_print_modalias_bits(buf: buf + len, size: size - len,
1417 name: 'w', bm: id->swbit, min_bit: 0, SW_MAX);
1418
1419 if (add_cr)
1420 len += snprintf(buf: buf + len, max(size - len, 0), fmt: "\n");
1421
1422 return len;
1423}
1424
1425static ssize_t input_dev_show_modalias(struct device *dev,
1426 struct device_attribute *attr,
1427 char *buf)
1428{
1429 struct input_dev *id = to_input_dev(dev);
1430 ssize_t len;
1431
1432 len = input_print_modalias(buf, PAGE_SIZE, id, add_cr: 1);
1433
1434 return min_t(int, len, PAGE_SIZE);
1435}
1436static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1437
1438static int input_print_bitmap(char *buf, int buf_size, const unsigned long *bitmap,
1439 int max, int add_cr);
1440
1441static ssize_t input_dev_show_properties(struct device *dev,
1442 struct device_attribute *attr,
1443 char *buf)
1444{
1445 struct input_dev *input_dev = to_input_dev(dev);
1446 int len = input_print_bitmap(buf, PAGE_SIZE, bitmap: input_dev->propbit,
1447 INPUT_PROP_MAX, add_cr: true);
1448 return min_t(int, len, PAGE_SIZE);
1449}
1450static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
1451
1452static int input_inhibit_device(struct input_dev *dev);
1453static int input_uninhibit_device(struct input_dev *dev);
1454
1455static ssize_t inhibited_show(struct device *dev,
1456 struct device_attribute *attr,
1457 char *buf)
1458{
1459 struct input_dev *input_dev = to_input_dev(dev);
1460
1461 return sysfs_emit(buf, fmt: "%d\n", input_dev->inhibited);
1462}
1463
1464static ssize_t inhibited_store(struct device *dev,
1465 struct device_attribute *attr, const char *buf,
1466 size_t len)
1467{
1468 struct input_dev *input_dev = to_input_dev(dev);
1469 ssize_t rv;
1470 bool inhibited;
1471
1472 if (kstrtobool(s: buf, res: &inhibited))
1473 return -EINVAL;
1474
1475 if (inhibited)
1476 rv = input_inhibit_device(dev: input_dev);
1477 else
1478 rv = input_uninhibit_device(dev: input_dev);
1479
1480 if (rv != 0)
1481 return rv;
1482
1483 return len;
1484}
1485
1486static DEVICE_ATTR_RW(inhibited);
1487
1488static struct attribute *input_dev_attrs[] = {
1489 &dev_attr_name.attr,
1490 &dev_attr_phys.attr,
1491 &dev_attr_uniq.attr,
1492 &dev_attr_modalias.attr,
1493 &dev_attr_properties.attr,
1494 &dev_attr_inhibited.attr,
1495 NULL
1496};
1497
1498static const struct attribute_group input_dev_attr_group = {
1499 .attrs = input_dev_attrs,
1500};
1501
1502#define INPUT_DEV_ID_ATTR(name) \
1503static ssize_t input_dev_show_id_##name(struct device *dev, \
1504 struct device_attribute *attr, \
1505 char *buf) \
1506{ \
1507 struct input_dev *input_dev = to_input_dev(dev); \
1508 return sysfs_emit(buf, "%04x\n", input_dev->id.name); \
1509} \
1510static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1511
1512INPUT_DEV_ID_ATTR(bustype);
1513INPUT_DEV_ID_ATTR(vendor);
1514INPUT_DEV_ID_ATTR(product);
1515INPUT_DEV_ID_ATTR(version);
1516
1517static struct attribute *input_dev_id_attrs[] = {
1518 &dev_attr_bustype.attr,
1519 &dev_attr_vendor.attr,
1520 &dev_attr_product.attr,
1521 &dev_attr_version.attr,
1522 NULL
1523};
1524
1525static const struct attribute_group input_dev_id_attr_group = {
1526 .name = "id",
1527 .attrs = input_dev_id_attrs,
1528};
1529
1530static int input_print_bitmap(char *buf, int buf_size, const unsigned long *bitmap,
1531 int max, int add_cr)
1532{
1533 int i;
1534 int len = 0;
1535 bool skip_empty = true;
1536
1537 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1538 len += input_bits_to_string(buf: buf + len, max(buf_size - len, 0),
1539 bits: bitmap[i], skip_empty);
1540 if (len) {
1541 skip_empty = false;
1542 if (i > 0)
1543 len += snprintf(buf: buf + len, max(buf_size - len, 0), fmt: " ");
1544 }
1545 }
1546
1547 /*
1548 * If no output was produced print a single 0.
1549 */
1550 if (len == 0)
1551 len = snprintf(buf, size: buf_size, fmt: "%d", 0);
1552
1553 if (add_cr)
1554 len += snprintf(buf: buf + len, max(buf_size - len, 0), fmt: "\n");
1555
1556 return len;
1557}
1558
1559#define INPUT_DEV_CAP_ATTR(ev, bm) \
1560static ssize_t input_dev_show_cap_##bm(struct device *dev, \
1561 struct device_attribute *attr, \
1562 char *buf) \
1563{ \
1564 struct input_dev *input_dev = to_input_dev(dev); \
1565 int len = input_print_bitmap(buf, PAGE_SIZE, \
1566 input_dev->bm##bit, ev##_MAX, \
1567 true); \
1568 return min_t(int, len, PAGE_SIZE); \
1569} \
1570static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1571
1572INPUT_DEV_CAP_ATTR(EV, ev);
1573INPUT_DEV_CAP_ATTR(KEY, key);
1574INPUT_DEV_CAP_ATTR(REL, rel);
1575INPUT_DEV_CAP_ATTR(ABS, abs);
1576INPUT_DEV_CAP_ATTR(MSC, msc);
1577INPUT_DEV_CAP_ATTR(LED, led);
1578INPUT_DEV_CAP_ATTR(SND, snd);
1579INPUT_DEV_CAP_ATTR(FF, ff);
1580INPUT_DEV_CAP_ATTR(SW, sw);
1581
1582static struct attribute *input_dev_caps_attrs[] = {
1583 &dev_attr_ev.attr,
1584 &dev_attr_key.attr,
1585 &dev_attr_rel.attr,
1586 &dev_attr_abs.attr,
1587 &dev_attr_msc.attr,
1588 &dev_attr_led.attr,
1589 &dev_attr_snd.attr,
1590 &dev_attr_ff.attr,
1591 &dev_attr_sw.attr,
1592 NULL
1593};
1594
1595static const struct attribute_group input_dev_caps_attr_group = {
1596 .name = "capabilities",
1597 .attrs = input_dev_caps_attrs,
1598};
1599
1600static const struct attribute_group *input_dev_attr_groups[] = {
1601 &input_dev_attr_group,
1602 &input_dev_id_attr_group,
1603 &input_dev_caps_attr_group,
1604 &input_poller_attribute_group,
1605 NULL
1606};
1607
1608static void input_dev_release(struct device *device)
1609{
1610 struct input_dev *dev = to_input_dev(device);
1611
1612 input_ff_destroy(dev);
1613 input_mt_destroy_slots(dev);
1614 kfree(objp: dev->poller);
1615 kfree(objp: dev->absinfo);
1616 kfree(objp: dev->vals);
1617 kfree(objp: dev);
1618
1619 module_put(THIS_MODULE);
1620}
1621
1622/*
1623 * Input uevent interface - loading event handlers based on
1624 * device bitfields.
1625 */
1626static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1627 const char *name, const unsigned long *bitmap, int max)
1628{
1629 int len;
1630
1631 if (add_uevent_var(env, format: "%s", name))
1632 return -ENOMEM;
1633
1634 len = input_print_bitmap(buf: &env->buf[env->buflen - 1],
1635 buf_size: sizeof(env->buf) - env->buflen,
1636 bitmap, max, add_cr: false);
1637 if (len >= (sizeof(env->buf) - env->buflen))
1638 return -ENOMEM;
1639
1640 env->buflen += len;
1641 return 0;
1642}
1643
1644static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1645 const struct input_dev *dev)
1646{
1647 int len;
1648
1649 if (add_uevent_var(env, format: "MODALIAS="))
1650 return -ENOMEM;
1651
1652 len = input_print_modalias(buf: &env->buf[env->buflen - 1],
1653 size: sizeof(env->buf) - env->buflen,
1654 id: dev, add_cr: 0);
1655 if (len >= (sizeof(env->buf) - env->buflen))
1656 return -ENOMEM;
1657
1658 env->buflen += len;
1659 return 0;
1660}
1661
1662#define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \
1663 do { \
1664 int err = add_uevent_var(env, fmt, val); \
1665 if (err) \
1666 return err; \
1667 } while (0)
1668
1669#define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max) \
1670 do { \
1671 int err = input_add_uevent_bm_var(env, name, bm, max); \
1672 if (err) \
1673 return err; \
1674 } while (0)
1675
1676#define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \
1677 do { \
1678 int err = input_add_uevent_modalias_var(env, dev); \
1679 if (err) \
1680 return err; \
1681 } while (0)
1682
1683static int input_dev_uevent(const struct device *device, struct kobj_uevent_env *env)
1684{
1685 const struct input_dev *dev = to_input_dev(device);
1686
1687 INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1688 dev->id.bustype, dev->id.vendor,
1689 dev->id.product, dev->id.version);
1690 if (dev->name)
1691 INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1692 if (dev->phys)
1693 INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1694 if (dev->uniq)
1695 INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1696
1697 INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
1698
1699 INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1700 if (test_bit(EV_KEY, dev->evbit))
1701 INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1702 if (test_bit(EV_REL, dev->evbit))
1703 INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1704 if (test_bit(EV_ABS, dev->evbit))
1705 INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1706 if (test_bit(EV_MSC, dev->evbit))
1707 INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1708 if (test_bit(EV_LED, dev->evbit))
1709 INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1710 if (test_bit(EV_SND, dev->evbit))
1711 INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1712 if (test_bit(EV_FF, dev->evbit))
1713 INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1714 if (test_bit(EV_SW, dev->evbit))
1715 INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1716
1717 INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1718
1719 return 0;
1720}
1721
1722#define INPUT_DO_TOGGLE(dev, type, bits, on) \
1723 do { \
1724 int i; \
1725 bool active; \
1726 \
1727 if (!test_bit(EV_##type, dev->evbit)) \
1728 break; \
1729 \
1730 for_each_set_bit(i, dev->bits##bit, type##_CNT) { \
1731 active = test_bit(i, dev->bits); \
1732 if (!active && !on) \
1733 continue; \
1734 \
1735 dev->event(dev, EV_##type, i, on ? active : 0); \
1736 } \
1737 } while (0)
1738
1739static void input_dev_toggle(struct input_dev *dev, bool activate)
1740{
1741 if (!dev->event)
1742 return;
1743
1744 INPUT_DO_TOGGLE(dev, LED, led, activate);
1745 INPUT_DO_TOGGLE(dev, SND, snd, activate);
1746
1747 if (activate && test_bit(EV_REP, dev->evbit)) {
1748 dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1749 dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1750 }
1751}
1752
1753/**
1754 * input_reset_device() - reset/restore the state of input device
1755 * @dev: input device whose state needs to be reset
1756 *
1757 * This function tries to reset the state of an opened input device and
1758 * bring internal state and state if the hardware in sync with each other.
1759 * We mark all keys as released, restore LED state, repeat rate, etc.
1760 */
1761void input_reset_device(struct input_dev *dev)
1762{
1763 unsigned long flags;
1764
1765 mutex_lock(&dev->mutex);
1766 spin_lock_irqsave(&dev->event_lock, flags);
1767
1768 input_dev_toggle(dev, activate: true);
1769 if (input_dev_release_keys(dev))
1770 input_handle_event(dev, EV_SYN, SYN_REPORT, value: 1);
1771
1772 spin_unlock_irqrestore(lock: &dev->event_lock, flags);
1773 mutex_unlock(lock: &dev->mutex);
1774}
1775EXPORT_SYMBOL(input_reset_device);
1776
1777static int input_inhibit_device(struct input_dev *dev)
1778{
1779 mutex_lock(&dev->mutex);
1780
1781 if (dev->inhibited)
1782 goto out;
1783
1784 if (dev->users) {
1785 if (dev->close)
1786 dev->close(dev);
1787 if (dev->poller)
1788 input_dev_poller_stop(poller: dev->poller);
1789 }
1790
1791 spin_lock_irq(lock: &dev->event_lock);
1792 input_mt_release_slots(dev);
1793 input_dev_release_keys(dev);
1794 input_handle_event(dev, EV_SYN, SYN_REPORT, value: 1);
1795 input_dev_toggle(dev, activate: false);
1796 spin_unlock_irq(lock: &dev->event_lock);
1797
1798 dev->inhibited = true;
1799
1800out:
1801 mutex_unlock(lock: &dev->mutex);
1802 return 0;
1803}
1804
1805static int input_uninhibit_device(struct input_dev *dev)
1806{
1807 int ret = 0;
1808
1809 mutex_lock(&dev->mutex);
1810
1811 if (!dev->inhibited)
1812 goto out;
1813
1814 if (dev->users) {
1815 if (dev->open) {
1816 ret = dev->open(dev);
1817 if (ret)
1818 goto out;
1819 }
1820 if (dev->poller)
1821 input_dev_poller_start(poller: dev->poller);
1822 }
1823
1824 dev->inhibited = false;
1825 spin_lock_irq(lock: &dev->event_lock);
1826 input_dev_toggle(dev, activate: true);
1827 spin_unlock_irq(lock: &dev->event_lock);
1828
1829out:
1830 mutex_unlock(lock: &dev->mutex);
1831 return ret;
1832}
1833
1834static int input_dev_suspend(struct device *dev)
1835{
1836 struct input_dev *input_dev = to_input_dev(dev);
1837
1838 spin_lock_irq(lock: &input_dev->event_lock);
1839
1840 /*
1841 * Keys that are pressed now are unlikely to be
1842 * still pressed when we resume.
1843 */
1844 if (input_dev_release_keys(dev: input_dev))
1845 input_handle_event(dev: input_dev, EV_SYN, SYN_REPORT, value: 1);
1846
1847 /* Turn off LEDs and sounds, if any are active. */
1848 input_dev_toggle(dev: input_dev, activate: false);
1849
1850 spin_unlock_irq(lock: &input_dev->event_lock);
1851
1852 return 0;
1853}
1854
1855static int input_dev_resume(struct device *dev)
1856{
1857 struct input_dev *input_dev = to_input_dev(dev);
1858
1859 spin_lock_irq(lock: &input_dev->event_lock);
1860
1861 /* Restore state of LEDs and sounds, if any were active. */
1862 input_dev_toggle(dev: input_dev, activate: true);
1863
1864 spin_unlock_irq(lock: &input_dev->event_lock);
1865
1866 return 0;
1867}
1868
1869static int input_dev_freeze(struct device *dev)
1870{
1871 struct input_dev *input_dev = to_input_dev(dev);
1872
1873 spin_lock_irq(lock: &input_dev->event_lock);
1874
1875 /*
1876 * Keys that are pressed now are unlikely to be
1877 * still pressed when we resume.
1878 */
1879 if (input_dev_release_keys(dev: input_dev))
1880 input_handle_event(dev: input_dev, EV_SYN, SYN_REPORT, value: 1);
1881
1882 spin_unlock_irq(lock: &input_dev->event_lock);
1883
1884 return 0;
1885}
1886
1887static int input_dev_poweroff(struct device *dev)
1888{
1889 struct input_dev *input_dev = to_input_dev(dev);
1890
1891 spin_lock_irq(lock: &input_dev->event_lock);
1892
1893 /* Turn off LEDs and sounds, if any are active. */
1894 input_dev_toggle(dev: input_dev, activate: false);
1895
1896 spin_unlock_irq(lock: &input_dev->event_lock);
1897
1898 return 0;
1899}
1900
1901static const struct dev_pm_ops input_dev_pm_ops = {
1902 .suspend = input_dev_suspend,
1903 .resume = input_dev_resume,
1904 .freeze = input_dev_freeze,
1905 .poweroff = input_dev_poweroff,
1906 .restore = input_dev_resume,
1907};
1908
1909static const struct device_type input_dev_type = {
1910 .groups = input_dev_attr_groups,
1911 .release = input_dev_release,
1912 .uevent = input_dev_uevent,
1913 .pm = pm_sleep_ptr(&input_dev_pm_ops),
1914};
1915
1916static char *input_devnode(const struct device *dev, umode_t *mode)
1917{
1918 return kasprintf(GFP_KERNEL, fmt: "input/%s", dev_name(dev));
1919}
1920
1921const struct class input_class = {
1922 .name = "input",
1923 .devnode = input_devnode,
1924};
1925EXPORT_SYMBOL_GPL(input_class);
1926
1927/**
1928 * input_allocate_device - allocate memory for new input device
1929 *
1930 * Returns prepared struct input_dev or %NULL.
1931 *
1932 * NOTE: Use input_free_device() to free devices that have not been
1933 * registered; input_unregister_device() should be used for already
1934 * registered devices.
1935 */
1936struct input_dev *input_allocate_device(void)
1937{
1938 static atomic_t input_no = ATOMIC_INIT(-1);
1939 struct input_dev *dev;
1940
1941 dev = kzalloc(size: sizeof(*dev), GFP_KERNEL);
1942 if (dev) {
1943 dev->dev.type = &input_dev_type;
1944 dev->dev.class = &input_class;
1945 device_initialize(dev: &dev->dev);
1946 mutex_init(&dev->mutex);
1947 spin_lock_init(&dev->event_lock);
1948 timer_setup(&dev->timer, NULL, 0);
1949 INIT_LIST_HEAD(list: &dev->h_list);
1950 INIT_LIST_HEAD(list: &dev->node);
1951
1952 dev_set_name(dev: &dev->dev, name: "input%lu",
1953 (unsigned long)atomic_inc_return(v: &input_no));
1954
1955 __module_get(THIS_MODULE);
1956 }
1957
1958 return dev;
1959}
1960EXPORT_SYMBOL(input_allocate_device);
1961
1962struct input_devres {
1963 struct input_dev *input;
1964};
1965
1966static int devm_input_device_match(struct device *dev, void *res, void *data)
1967{
1968 struct input_devres *devres = res;
1969
1970 return devres->input == data;
1971}
1972
1973static void devm_input_device_release(struct device *dev, void *res)
1974{
1975 struct input_devres *devres = res;
1976 struct input_dev *input = devres->input;
1977
1978 dev_dbg(dev, "%s: dropping reference to %s\n",
1979 __func__, dev_name(&input->dev));
1980 input_put_device(dev: input);
1981}
1982
1983/**
1984 * devm_input_allocate_device - allocate managed input device
1985 * @dev: device owning the input device being created
1986 *
1987 * Returns prepared struct input_dev or %NULL.
1988 *
1989 * Managed input devices do not need to be explicitly unregistered or
1990 * freed as it will be done automatically when owner device unbinds from
1991 * its driver (or binding fails). Once managed input device is allocated,
1992 * it is ready to be set up and registered in the same fashion as regular
1993 * input device. There are no special devm_input_device_[un]register()
1994 * variants, regular ones work with both managed and unmanaged devices,
1995 * should you need them. In most cases however, managed input device need
1996 * not be explicitly unregistered or freed.
1997 *
1998 * NOTE: the owner device is set up as parent of input device and users
1999 * should not override it.
2000 */
2001struct input_dev *devm_input_allocate_device(struct device *dev)
2002{
2003 struct input_dev *input;
2004 struct input_devres *devres;
2005
2006 devres = devres_alloc(devm_input_device_release,
2007 sizeof(*devres), GFP_KERNEL);
2008 if (!devres)
2009 return NULL;
2010
2011 input = input_allocate_device();
2012 if (!input) {
2013 devres_free(res: devres);
2014 return NULL;
2015 }
2016
2017 input->dev.parent = dev;
2018 input->devres_managed = true;
2019
2020 devres->input = input;
2021 devres_add(dev, res: devres);
2022
2023 return input;
2024}
2025EXPORT_SYMBOL(devm_input_allocate_device);
2026
2027/**
2028 * input_free_device - free memory occupied by input_dev structure
2029 * @dev: input device to free
2030 *
2031 * This function should only be used if input_register_device()
2032 * was not called yet or if it failed. Once device was registered
2033 * use input_unregister_device() and memory will be freed once last
2034 * reference to the device is dropped.
2035 *
2036 * Device should be allocated by input_allocate_device().
2037 *
2038 * NOTE: If there are references to the input device then memory
2039 * will not be freed until last reference is dropped.
2040 */
2041void input_free_device(struct input_dev *dev)
2042{
2043 if (dev) {
2044 if (dev->devres_managed)
2045 WARN_ON(devres_destroy(dev->dev.parent,
2046 devm_input_device_release,
2047 devm_input_device_match,
2048 dev));
2049 input_put_device(dev);
2050 }
2051}
2052EXPORT_SYMBOL(input_free_device);
2053
2054/**
2055 * input_set_timestamp - set timestamp for input events
2056 * @dev: input device to set timestamp for
2057 * @timestamp: the time at which the event has occurred
2058 * in CLOCK_MONOTONIC
2059 *
2060 * This function is intended to provide to the input system a more
2061 * accurate time of when an event actually occurred. The driver should
2062 * call this function as soon as a timestamp is acquired ensuring
2063 * clock conversions in input_set_timestamp are done correctly.
2064 *
2065 * The system entering suspend state between timestamp acquisition and
2066 * calling input_set_timestamp can result in inaccurate conversions.
2067 */
2068void input_set_timestamp(struct input_dev *dev, ktime_t timestamp)
2069{
2070 dev->timestamp[INPUT_CLK_MONO] = timestamp;
2071 dev->timestamp[INPUT_CLK_REAL] = ktime_mono_to_real(mono: timestamp);
2072 dev->timestamp[INPUT_CLK_BOOT] = ktime_mono_to_any(tmono: timestamp,
2073 offs: TK_OFFS_BOOT);
2074}
2075EXPORT_SYMBOL(input_set_timestamp);
2076
2077/**
2078 * input_get_timestamp - get timestamp for input events
2079 * @dev: input device to get timestamp from
2080 *
2081 * A valid timestamp is a timestamp of non-zero value.
2082 */
2083ktime_t *input_get_timestamp(struct input_dev *dev)
2084{
2085 const ktime_t invalid_timestamp = ktime_set(secs: 0, nsecs: 0);
2086
2087 if (!ktime_compare(cmp1: dev->timestamp[INPUT_CLK_MONO], cmp2: invalid_timestamp))
2088 input_set_timestamp(dev, ktime_get());
2089
2090 return dev->timestamp;
2091}
2092EXPORT_SYMBOL(input_get_timestamp);
2093
2094/**
2095 * input_set_capability - mark device as capable of a certain event
2096 * @dev: device that is capable of emitting or accepting event
2097 * @type: type of the event (EV_KEY, EV_REL, etc...)
2098 * @code: event code
2099 *
2100 * In addition to setting up corresponding bit in appropriate capability
2101 * bitmap the function also adjusts dev->evbit.
2102 */
2103void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
2104{
2105 if (type < EV_CNT && input_max_code[type] &&
2106 code > input_max_code[type]) {
2107 pr_err("%s: invalid code %u for type %u\n", __func__, code,
2108 type);
2109 dump_stack();
2110 return;
2111 }
2112
2113 switch (type) {
2114 case EV_KEY:
2115 __set_bit(code, dev->keybit);
2116 break;
2117
2118 case EV_REL:
2119 __set_bit(code, dev->relbit);
2120 break;
2121
2122 case EV_ABS:
2123 input_alloc_absinfo(dev);
2124 __set_bit(code, dev->absbit);
2125 break;
2126
2127 case EV_MSC:
2128 __set_bit(code, dev->mscbit);
2129 break;
2130
2131 case EV_SW:
2132 __set_bit(code, dev->swbit);
2133 break;
2134
2135 case EV_LED:
2136 __set_bit(code, dev->ledbit);
2137 break;
2138
2139 case EV_SND:
2140 __set_bit(code, dev->sndbit);
2141 break;
2142
2143 case EV_FF:
2144 __set_bit(code, dev->ffbit);
2145 break;
2146
2147 case EV_PWR:
2148 /* do nothing */
2149 break;
2150
2151 default:
2152 pr_err("%s: unknown type %u (code %u)\n", __func__, type, code);
2153 dump_stack();
2154 return;
2155 }
2156
2157 __set_bit(type, dev->evbit);
2158}
2159EXPORT_SYMBOL(input_set_capability);
2160
2161static unsigned int input_estimate_events_per_packet(struct input_dev *dev)
2162{
2163 int mt_slots;
2164 int i;
2165 unsigned int events;
2166
2167 if (dev->mt) {
2168 mt_slots = dev->mt->num_slots;
2169 } else if (test_bit(ABS_MT_TRACKING_ID, dev->absbit)) {
2170 mt_slots = dev->absinfo[ABS_MT_TRACKING_ID].maximum -
2171 dev->absinfo[ABS_MT_TRACKING_ID].minimum + 1,
2172 mt_slots = clamp(mt_slots, 2, 32);
2173 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
2174 mt_slots = 2;
2175 } else {
2176 mt_slots = 0;
2177 }
2178
2179 events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */
2180
2181 if (test_bit(EV_ABS, dev->evbit))
2182 for_each_set_bit(i, dev->absbit, ABS_CNT)
2183 events += input_is_mt_axis(axis: i) ? mt_slots : 1;
2184
2185 if (test_bit(EV_REL, dev->evbit))
2186 events += bitmap_weight(src: dev->relbit, REL_CNT);
2187
2188 /* Make room for KEY and MSC events */
2189 events += 7;
2190
2191 return events;
2192}
2193
2194#define INPUT_CLEANSE_BITMASK(dev, type, bits) \
2195 do { \
2196 if (!test_bit(EV_##type, dev->evbit)) \
2197 memset(dev->bits##bit, 0, \
2198 sizeof(dev->bits##bit)); \
2199 } while (0)
2200
2201static void input_cleanse_bitmasks(struct input_dev *dev)
2202{
2203 INPUT_CLEANSE_BITMASK(dev, KEY, key);
2204 INPUT_CLEANSE_BITMASK(dev, REL, rel);
2205 INPUT_CLEANSE_BITMASK(dev, ABS, abs);
2206 INPUT_CLEANSE_BITMASK(dev, MSC, msc);
2207 INPUT_CLEANSE_BITMASK(dev, LED, led);
2208 INPUT_CLEANSE_BITMASK(dev, SND, snd);
2209 INPUT_CLEANSE_BITMASK(dev, FF, ff);
2210 INPUT_CLEANSE_BITMASK(dev, SW, sw);
2211}
2212
2213static void __input_unregister_device(struct input_dev *dev)
2214{
2215 struct input_handle *handle, *next;
2216
2217 input_disconnect_device(dev);
2218
2219 mutex_lock(&input_mutex);
2220
2221 list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
2222 handle->handler->disconnect(handle);
2223 WARN_ON(!list_empty(&dev->h_list));
2224
2225 del_timer_sync(timer: &dev->timer);
2226 list_del_init(entry: &dev->node);
2227
2228 input_wakeup_procfs_readers();
2229
2230 mutex_unlock(lock: &input_mutex);
2231
2232 device_del(dev: &dev->dev);
2233}
2234
2235static void devm_input_device_unregister(struct device *dev, void *res)
2236{
2237 struct input_devres *devres = res;
2238 struct input_dev *input = devres->input;
2239
2240 dev_dbg(dev, "%s: unregistering device %s\n",
2241 __func__, dev_name(&input->dev));
2242 __input_unregister_device(dev: input);
2243}
2244
2245/*
2246 * Generate software autorepeat event. Note that we take
2247 * dev->event_lock here to avoid racing with input_event
2248 * which may cause keys get "stuck".
2249 */
2250static void input_repeat_key(struct timer_list *t)
2251{
2252 struct input_dev *dev = from_timer(dev, t, timer);
2253 unsigned long flags;
2254
2255 spin_lock_irqsave(&dev->event_lock, flags);
2256
2257 if (!dev->inhibited &&
2258 test_bit(dev->repeat_key, dev->key) &&
2259 is_event_supported(code: dev->repeat_key, bm: dev->keybit, KEY_MAX)) {
2260
2261 input_set_timestamp(dev, ktime_get());
2262 input_handle_event(dev, EV_KEY, code: dev->repeat_key, value: 2);
2263 input_handle_event(dev, EV_SYN, SYN_REPORT, value: 1);
2264
2265 if (dev->rep[REP_PERIOD])
2266 mod_timer(timer: &dev->timer, expires: jiffies +
2267 msecs_to_jiffies(m: dev->rep[REP_PERIOD]));
2268 }
2269
2270 spin_unlock_irqrestore(lock: &dev->event_lock, flags);
2271}
2272
2273/**
2274 * input_enable_softrepeat - enable software autorepeat
2275 * @dev: input device
2276 * @delay: repeat delay
2277 * @period: repeat period
2278 *
2279 * Enable software autorepeat on the input device.
2280 */
2281void input_enable_softrepeat(struct input_dev *dev, int delay, int period)
2282{
2283 dev->timer.function = input_repeat_key;
2284 dev->rep[REP_DELAY] = delay;
2285 dev->rep[REP_PERIOD] = period;
2286}
2287EXPORT_SYMBOL(input_enable_softrepeat);
2288
2289bool input_device_enabled(struct input_dev *dev)
2290{
2291 lockdep_assert_held(&dev->mutex);
2292
2293 return !dev->inhibited && dev->users > 0;
2294}
2295EXPORT_SYMBOL_GPL(input_device_enabled);
2296
2297/**
2298 * input_register_device - register device with input core
2299 * @dev: device to be registered
2300 *
2301 * This function registers device with input core. The device must be
2302 * allocated with input_allocate_device() and all it's capabilities
2303 * set up before registering.
2304 * If function fails the device must be freed with input_free_device().
2305 * Once device has been successfully registered it can be unregistered
2306 * with input_unregister_device(); input_free_device() should not be
2307 * called in this case.
2308 *
2309 * Note that this function is also used to register managed input devices
2310 * (ones allocated with devm_input_allocate_device()). Such managed input
2311 * devices need not be explicitly unregistered or freed, their tear down
2312 * is controlled by the devres infrastructure. It is also worth noting
2313 * that tear down of managed input devices is internally a 2-step process:
2314 * registered managed input device is first unregistered, but stays in
2315 * memory and can still handle input_event() calls (although events will
2316 * not be delivered anywhere). The freeing of managed input device will
2317 * happen later, when devres stack is unwound to the point where device
2318 * allocation was made.
2319 */
2320int input_register_device(struct input_dev *dev)
2321{
2322 struct input_devres *devres = NULL;
2323 struct input_handler *handler;
2324 unsigned int packet_size;
2325 const char *path;
2326 int error;
2327
2328 if (test_bit(EV_ABS, dev->evbit) && !dev->absinfo) {
2329 dev_err(&dev->dev,
2330 "Absolute device without dev->absinfo, refusing to register\n");
2331 return -EINVAL;
2332 }
2333
2334 if (dev->devres_managed) {
2335 devres = devres_alloc(devm_input_device_unregister,
2336 sizeof(*devres), GFP_KERNEL);
2337 if (!devres)
2338 return -ENOMEM;
2339
2340 devres->input = dev;
2341 }
2342
2343 /* Every input device generates EV_SYN/SYN_REPORT events. */
2344 __set_bit(EV_SYN, dev->evbit);
2345
2346 /* KEY_RESERVED is not supposed to be transmitted to userspace. */
2347 __clear_bit(KEY_RESERVED, dev->keybit);
2348
2349 /* Make sure that bitmasks not mentioned in dev->evbit are clean. */
2350 input_cleanse_bitmasks(dev);
2351
2352 packet_size = input_estimate_events_per_packet(dev);
2353 if (dev->hint_events_per_packet < packet_size)
2354 dev->hint_events_per_packet = packet_size;
2355
2356 dev->max_vals = dev->hint_events_per_packet + 2;
2357 dev->vals = kcalloc(n: dev->max_vals, size: sizeof(*dev->vals), GFP_KERNEL);
2358 if (!dev->vals) {
2359 error = -ENOMEM;
2360 goto err_devres_free;
2361 }
2362
2363 /*
2364 * If delay and period are pre-set by the driver, then autorepeating
2365 * is handled by the driver itself and we don't do it in input.c.
2366 */
2367 if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD])
2368 input_enable_softrepeat(dev, 250, 33);
2369
2370 if (!dev->getkeycode)
2371 dev->getkeycode = input_default_getkeycode;
2372
2373 if (!dev->setkeycode)
2374 dev->setkeycode = input_default_setkeycode;
2375
2376 if (dev->poller)
2377 input_dev_poller_finalize(poller: dev->poller);
2378
2379 error = device_add(dev: &dev->dev);
2380 if (error)
2381 goto err_free_vals;
2382
2383 path = kobject_get_path(kobj: &dev->dev.kobj, GFP_KERNEL);
2384 pr_info("%s as %s\n",
2385 dev->name ? dev->name : "Unspecified device",
2386 path ? path : "N/A");
2387 kfree(objp: path);
2388
2389 error = mutex_lock_interruptible(&input_mutex);
2390 if (error)
2391 goto err_device_del;
2392
2393 list_add_tail(new: &dev->node, head: &input_dev_list);
2394
2395 list_for_each_entry(handler, &input_handler_list, node)
2396 input_attach_handler(dev, handler);
2397
2398 input_wakeup_procfs_readers();
2399
2400 mutex_unlock(lock: &input_mutex);
2401
2402 if (dev->devres_managed) {
2403 dev_dbg(dev->dev.parent, "%s: registering %s with devres.\n",
2404 __func__, dev_name(&dev->dev));
2405 devres_add(dev: dev->dev.parent, res: devres);
2406 }
2407 return 0;
2408
2409err_device_del:
2410 device_del(dev: &dev->dev);
2411err_free_vals:
2412 kfree(objp: dev->vals);
2413 dev->vals = NULL;
2414err_devres_free:
2415 devres_free(res: devres);
2416 return error;
2417}
2418EXPORT_SYMBOL(input_register_device);
2419
2420/**
2421 * input_unregister_device - unregister previously registered device
2422 * @dev: device to be unregistered
2423 *
2424 * This function unregisters an input device. Once device is unregistered
2425 * the caller should not try to access it as it may get freed at any moment.
2426 */
2427void input_unregister_device(struct input_dev *dev)
2428{
2429 if (dev->devres_managed) {
2430 WARN_ON(devres_destroy(dev->dev.parent,
2431 devm_input_device_unregister,
2432 devm_input_device_match,
2433 dev));
2434 __input_unregister_device(dev);
2435 /*
2436 * We do not do input_put_device() here because it will be done
2437 * when 2nd devres fires up.
2438 */
2439 } else {
2440 __input_unregister_device(dev);
2441 input_put_device(dev);
2442 }
2443}
2444EXPORT_SYMBOL(input_unregister_device);
2445
2446/**
2447 * input_register_handler - register a new input handler
2448 * @handler: handler to be registered
2449 *
2450 * This function registers a new input handler (interface) for input
2451 * devices in the system and attaches it to all input devices that
2452 * are compatible with the handler.
2453 */
2454int input_register_handler(struct input_handler *handler)
2455{
2456 struct input_dev *dev;
2457 int error;
2458
2459 error = mutex_lock_interruptible(&input_mutex);
2460 if (error)
2461 return error;
2462
2463 INIT_LIST_HEAD(list: &handler->h_list);
2464
2465 list_add_tail(new: &handler->node, head: &input_handler_list);
2466
2467 list_for_each_entry(dev, &input_dev_list, node)
2468 input_attach_handler(dev, handler);
2469
2470 input_wakeup_procfs_readers();
2471
2472 mutex_unlock(lock: &input_mutex);
2473 return 0;
2474}
2475EXPORT_SYMBOL(input_register_handler);
2476
2477/**
2478 * input_unregister_handler - unregisters an input handler
2479 * @handler: handler to be unregistered
2480 *
2481 * This function disconnects a handler from its input devices and
2482 * removes it from lists of known handlers.
2483 */
2484void input_unregister_handler(struct input_handler *handler)
2485{
2486 struct input_handle *handle, *next;
2487
2488 mutex_lock(&input_mutex);
2489
2490 list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
2491 handler->disconnect(handle);
2492 WARN_ON(!list_empty(&handler->h_list));
2493
2494 list_del_init(entry: &handler->node);
2495
2496 input_wakeup_procfs_readers();
2497
2498 mutex_unlock(lock: &input_mutex);
2499}
2500EXPORT_SYMBOL(input_unregister_handler);
2501
2502/**
2503 * input_handler_for_each_handle - handle iterator
2504 * @handler: input handler to iterate
2505 * @data: data for the callback
2506 * @fn: function to be called for each handle
2507 *
2508 * Iterate over @bus's list of devices, and call @fn for each, passing
2509 * it @data and stop when @fn returns a non-zero value. The function is
2510 * using RCU to traverse the list and therefore may be using in atomic
2511 * contexts. The @fn callback is invoked from RCU critical section and
2512 * thus must not sleep.
2513 */
2514int input_handler_for_each_handle(struct input_handler *handler, void *data,
2515 int (*fn)(struct input_handle *, void *))
2516{
2517 struct input_handle *handle;
2518 int retval = 0;
2519
2520 rcu_read_lock();
2521
2522 list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
2523 retval = fn(handle, data);
2524 if (retval)
2525 break;
2526 }
2527
2528 rcu_read_unlock();
2529
2530 return retval;
2531}
2532EXPORT_SYMBOL(input_handler_for_each_handle);
2533
2534/**
2535 * input_register_handle - register a new input handle
2536 * @handle: handle to register
2537 *
2538 * This function puts a new input handle onto device's
2539 * and handler's lists so that events can flow through
2540 * it once it is opened using input_open_device().
2541 *
2542 * This function is supposed to be called from handler's
2543 * connect() method.
2544 */
2545int input_register_handle(struct input_handle *handle)
2546{
2547 struct input_handler *handler = handle->handler;
2548 struct input_dev *dev = handle->dev;
2549 int error;
2550
2551 /*
2552 * We take dev->mutex here to prevent race with
2553 * input_release_device().
2554 */
2555 error = mutex_lock_interruptible(&dev->mutex);
2556 if (error)
2557 return error;
2558
2559 /*
2560 * Filters go to the head of the list, normal handlers
2561 * to the tail.
2562 */
2563 if (handler->filter)
2564 list_add_rcu(new: &handle->d_node, head: &dev->h_list);
2565 else
2566 list_add_tail_rcu(new: &handle->d_node, head: &dev->h_list);
2567
2568 mutex_unlock(lock: &dev->mutex);
2569
2570 /*
2571 * Since we are supposed to be called from ->connect()
2572 * which is mutually exclusive with ->disconnect()
2573 * we can't be racing with input_unregister_handle()
2574 * and so separate lock is not needed here.
2575 */
2576 list_add_tail_rcu(new: &handle->h_node, head: &handler->h_list);
2577
2578 if (handler->start)
2579 handler->start(handle);
2580
2581 return 0;
2582}
2583EXPORT_SYMBOL(input_register_handle);
2584
2585/**
2586 * input_unregister_handle - unregister an input handle
2587 * @handle: handle to unregister
2588 *
2589 * This function removes input handle from device's
2590 * and handler's lists.
2591 *
2592 * This function is supposed to be called from handler's
2593 * disconnect() method.
2594 */
2595void input_unregister_handle(struct input_handle *handle)
2596{
2597 struct input_dev *dev = handle->dev;
2598
2599 list_del_rcu(entry: &handle->h_node);
2600
2601 /*
2602 * Take dev->mutex to prevent race with input_release_device().
2603 */
2604 mutex_lock(&dev->mutex);
2605 list_del_rcu(entry: &handle->d_node);
2606 mutex_unlock(lock: &dev->mutex);
2607
2608 synchronize_rcu();
2609}
2610EXPORT_SYMBOL(input_unregister_handle);
2611
2612/**
2613 * input_get_new_minor - allocates a new input minor number
2614 * @legacy_base: beginning or the legacy range to be searched
2615 * @legacy_num: size of legacy range
2616 * @allow_dynamic: whether we can also take ID from the dynamic range
2617 *
2618 * This function allocates a new device minor for from input major namespace.
2619 * Caller can request legacy minor by specifying @legacy_base and @legacy_num
2620 * parameters and whether ID can be allocated from dynamic range if there are
2621 * no free IDs in legacy range.
2622 */
2623int input_get_new_minor(int legacy_base, unsigned int legacy_num,
2624 bool allow_dynamic)
2625{
2626 /*
2627 * This function should be called from input handler's ->connect()
2628 * methods, which are serialized with input_mutex, so no additional
2629 * locking is needed here.
2630 */
2631 if (legacy_base >= 0) {
2632 int minor = ida_alloc_range(&input_ida, min: legacy_base,
2633 max: legacy_base + legacy_num - 1,
2634 GFP_KERNEL);
2635 if (minor >= 0 || !allow_dynamic)
2636 return minor;
2637 }
2638
2639 return ida_alloc_range(&input_ida, INPUT_FIRST_DYNAMIC_DEV,
2640 INPUT_MAX_CHAR_DEVICES - 1, GFP_KERNEL);
2641}
2642EXPORT_SYMBOL(input_get_new_minor);
2643
2644/**
2645 * input_free_minor - release previously allocated minor
2646 * @minor: minor to be released
2647 *
2648 * This function releases previously allocated input minor so that it can be
2649 * reused later.
2650 */
2651void input_free_minor(unsigned int minor)
2652{
2653 ida_free(&input_ida, id: minor);
2654}
2655EXPORT_SYMBOL(input_free_minor);
2656
2657static int __init input_init(void)
2658{
2659 int err;
2660
2661 err = class_register(class: &input_class);
2662 if (err) {
2663 pr_err("unable to register input_dev class\n");
2664 return err;
2665 }
2666
2667 err = input_proc_init();
2668 if (err)
2669 goto fail1;
2670
2671 err = register_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2672 INPUT_MAX_CHAR_DEVICES, "input");
2673 if (err) {
2674 pr_err("unable to register char major %d", INPUT_MAJOR);
2675 goto fail2;
2676 }
2677
2678 return 0;
2679
2680 fail2: input_proc_exit();
2681 fail1: class_unregister(class: &input_class);
2682 return err;
2683}
2684
2685static void __exit input_exit(void)
2686{
2687 input_proc_exit();
2688 unregister_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2689 INPUT_MAX_CHAR_DEVICES);
2690 class_unregister(class: &input_class);
2691}
2692
2693subsys_initcall(input_init);
2694module_exit(input_exit);
2695

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source code of linux/drivers/input/input.c