projects/linux·blob v3.7 · refs

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