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