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