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x86/xen: resume timer irqs early
[linux/fpc-iii.git] / drivers / input / input.c
blobfcf77af288661e91844c09cdf6b16945c1c7311b
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
32 MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
33 MODULE_DESCRIPTION("Input core");
34 MODULE_LICENSE("GPL");
35
36 #define INPUT_MAX_CHAR_DEVICES 1024
37 #define INPUT_FIRST_DYNAMIC_DEV 256
38 static DEFINE_IDA(input_ida);
39
40 static LIST_HEAD(input_dev_list);
41 static 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 */
49 static DEFINE_MUTEX(input_mutex);
50
51 static const struct input_value input_value_sync = { EV_SYN, SYN_REPORT, 1 };
52
53 static 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
59 static 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
75 static 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
86 static 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 */
96 static 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 */
130 static 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
165 static 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 */
178 static 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
209 static 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
259 static int input_get_disposition(struct input_dev *dev,
260 unsigned int type, unsigned int code, int *pval)
261 {
262 int disposition = INPUT_IGNORE_EVENT;
263 int value = *pval;
264
265 switch (type) {
266
267 case EV_SYN:
268 switch (code) {
269 case SYN_CONFIG:
270 disposition = INPUT_PASS_TO_ALL;
271 break;
272
273 case SYN_REPORT:
274 disposition = INPUT_PASS_TO_HANDLERS | INPUT_FLUSH;
275 break;
276 case SYN_MT_REPORT:
277 disposition = INPUT_PASS_TO_HANDLERS;
278 break;
279 }
280 break;
281
282 case EV_KEY:
283 if (is_event_supported(code, dev->keybit, KEY_MAX)) {
284
285 /* auto-repeat bypasses state updates */
286 if (value == 2) {
287 disposition = INPUT_PASS_TO_HANDLERS;
288 break;
289 }
290
291 if (!!test_bit(code, dev->key) != !!value) {
292
293 __change_bit(code, dev->key);
294 disposition = INPUT_PASS_TO_HANDLERS;
295 }
296 }
297 break;
298
299 case EV_SW:
300 if (is_event_supported(code, dev->swbit, SW_MAX) &&
301 !!test_bit(code, dev->sw) != !!value) {
302
303 __change_bit(code, dev->sw);
304 disposition = INPUT_PASS_TO_HANDLERS;
305 }
306 break;
307
308 case EV_ABS:
309 if (is_event_supported(code, dev->absbit, ABS_MAX))
310 disposition = input_handle_abs_event(dev, code, &value);
311
312 break;
313
314 case EV_REL:
315 if (is_event_supported(code, dev->relbit, REL_MAX) && value)
316 disposition = INPUT_PASS_TO_HANDLERS;
317
318 break;
319
320 case EV_MSC:
321 if (is_event_supported(code, dev->mscbit, MSC_MAX))
322 disposition = INPUT_PASS_TO_ALL;
323
324 break;
325
326 case EV_LED:
327 if (is_event_supported(code, dev->ledbit, LED_MAX) &&
328 !!test_bit(code, dev->led) != !!value) {
329
330 __change_bit(code, dev->led);
331 disposition = INPUT_PASS_TO_ALL;
332 }
333 break;
334
335 case EV_SND:
336 if (is_event_supported(code, dev->sndbit, SND_MAX)) {
337
338 if (!!test_bit(code, dev->snd) != !!value)
339 __change_bit(code, dev->snd);
340 disposition = INPUT_PASS_TO_ALL;
341 }
342 break;
343
344 case EV_REP:
345 if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
346 dev->rep[code] = value;
347 disposition = INPUT_PASS_TO_ALL;
348 }
349 break;
350
351 case EV_FF:
352 if (value >= 0)
353 disposition = INPUT_PASS_TO_ALL;
354 break;
355
356 case EV_PWR:
357 disposition = INPUT_PASS_TO_ALL;
358 break;
359 }
360
361 *pval = value;
362 return disposition;
363 }
364
365 static void input_handle_event(struct input_dev *dev,
366 unsigned int type, unsigned int code, int value)
367 {
368 int disposition;
369
370 disposition = input_get_disposition(dev, type, code, &value);
371
372 if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
373 dev->event(dev, type, code, value);
374
375 if (!dev->vals)
376 return;
377
378 if (disposition & INPUT_PASS_TO_HANDLERS) {
379 struct input_value *v;
380
381 if (disposition & INPUT_SLOT) {
382 v = &dev->vals[dev->num_vals++];
383 v->type = EV_ABS;
384 v->code = ABS_MT_SLOT;
385 v->value = dev->mt->slot;
386 }
387
388 v = &dev->vals[dev->num_vals++];
389 v->type = type;
390 v->code = code;
391 v->value = value;
392 }
393
394 if (disposition & INPUT_FLUSH) {
395 if (dev->num_vals >= 2)
396 input_pass_values(dev, dev->vals, dev->num_vals);
397 dev->num_vals = 0;
398 } else if (dev->num_vals >= dev->max_vals - 2) {
399 dev->vals[dev->num_vals++] = input_value_sync;
400 input_pass_values(dev, dev->vals, dev->num_vals);
401 dev->num_vals = 0;
402 }
403
404 }
405
406 /**
407 * input_event() - report new input event
408 * @dev: device that generated the event
409 * @type: type of the event
410 * @code: event code
411 * @value: value of the event
412 *
413 * This function should be used by drivers implementing various input
414 * devices to report input events. See also input_inject_event().
415 *
416 * NOTE: input_event() may be safely used right after input device was
417 * allocated with input_allocate_device(), even before it is registered
418 * with input_register_device(), but the event will not reach any of the
419 * input handlers. Such early invocation of input_event() may be used
420 * to 'seed' initial state of a switch or initial position of absolute
421 * axis, etc.
422 */
423 void input_event(struct input_dev *dev,
424 unsigned int type, unsigned int code, int value)
425 {
426 unsigned long flags;
427
428 if (is_event_supported(type, dev->evbit, EV_MAX)) {
429
430 spin_lock_irqsave(&dev->event_lock, flags);
431 input_handle_event(dev, type, code, value);
432 spin_unlock_irqrestore(&dev->event_lock, flags);
433 }
434 }
435 EXPORT_SYMBOL(input_event);
436
437 /**
438 * input_inject_event() - send input event from input handler
439 * @handle: input handle to send event through
440 * @type: type of the event
441 * @code: event code
442 * @value: value of the event
443 *
444 * Similar to input_event() but will ignore event if device is
445 * "grabbed" and handle injecting event is not the one that owns
446 * the device.
447 */
448 void input_inject_event(struct input_handle *handle,
449 unsigned int type, unsigned int code, int value)
450 {
451 struct input_dev *dev = handle->dev;
452 struct input_handle *grab;
453 unsigned long flags;
454
455 if (is_event_supported(type, dev->evbit, EV_MAX)) {
456 spin_lock_irqsave(&dev->event_lock, flags);
457
458 rcu_read_lock();
459 grab = rcu_dereference(dev->grab);
460 if (!grab || grab == handle)
461 input_handle_event(dev, type, code, value);
462 rcu_read_unlock();
463
464 spin_unlock_irqrestore(&dev->event_lock, flags);
465 }
466 }
467 EXPORT_SYMBOL(input_inject_event);
468
469 /**
470 * input_alloc_absinfo - allocates array of input_absinfo structs
471 * @dev: the input device emitting absolute events
472 *
473 * If the absinfo struct the caller asked for is already allocated, this
474 * functions will not do anything.
475 */
476 void input_alloc_absinfo(struct input_dev *dev)
477 {
478 if (!dev->absinfo)
479 dev->absinfo = kcalloc(ABS_CNT, sizeof(struct input_absinfo),
480 GFP_KERNEL);
481
482 WARN(!dev->absinfo, "%s(): kcalloc() failed?\n", __func__);
483 }
484 EXPORT_SYMBOL(input_alloc_absinfo);
485
486 void input_set_abs_params(struct input_dev *dev, unsigned int axis,
487 int min, int max, int fuzz, int flat)
488 {
489 struct input_absinfo *absinfo;
490
491 input_alloc_absinfo(dev);
492 if (!dev->absinfo)
493 return;
494
495 absinfo = &dev->absinfo[axis];
496 absinfo->minimum = min;
497 absinfo->maximum = max;
498 absinfo->fuzz = fuzz;
499 absinfo->flat = flat;
500
501 dev->absbit[BIT_WORD(axis)] |= BIT_MASK(axis);
502 }
503 EXPORT_SYMBOL(input_set_abs_params);
504
505
506 /**
507 * input_grab_device - grabs device for exclusive use
508 * @handle: input handle that wants to own the device
509 *
510 * When a device is grabbed by an input handle all events generated by
511 * the device are delivered only to this handle. Also events injected
512 * by other input handles are ignored while device is grabbed.
513 */
514 int input_grab_device(struct input_handle *handle)
515 {
516 struct input_dev *dev = handle->dev;
517 int retval;
518
519 retval = mutex_lock_interruptible(&dev->mutex);
520 if (retval)
521 return retval;
522
523 if (dev->grab) {
524 retval = -EBUSY;
525 goto out;
526 }
527
528 rcu_assign_pointer(dev->grab, handle);
529
530 out:
531 mutex_unlock(&dev->mutex);
532 return retval;
533 }
534 EXPORT_SYMBOL(input_grab_device);
535
536 static void __input_release_device(struct input_handle *handle)
537 {
538 struct input_dev *dev = handle->dev;
539 struct input_handle *grabber;
540
541 grabber = rcu_dereference_protected(dev->grab,
542 lockdep_is_held(&dev->mutex));
543 if (grabber == handle) {
544 rcu_assign_pointer(dev->grab, NULL);
545 /* Make sure input_pass_event() notices that grab is gone */
546 synchronize_rcu();
547
548 list_for_each_entry(handle, &dev->h_list, d_node)
549 if (handle->open && handle->handler->start)
550 handle->handler->start(handle);
551 }
552 }
553
554 /**
555 * input_release_device - release previously grabbed device
556 * @handle: input handle that owns the device
557 *
558 * Releases previously grabbed device so that other input handles can
559 * start receiving input events. Upon release all handlers attached
560 * to the device have their start() method called so they have a change
561 * to synchronize device state with the rest of the system.
562 */
563 void input_release_device(struct input_handle *handle)
564 {
565 struct input_dev *dev = handle->dev;
566
567 mutex_lock(&dev->mutex);
568 __input_release_device(handle);
569 mutex_unlock(&dev->mutex);
570 }
571 EXPORT_SYMBOL(input_release_device);
572
573 /**
574 * input_open_device - open input device
575 * @handle: handle through which device is being accessed
576 *
577 * This function should be called by input handlers when they
578 * want to start receive events from given input device.
579 */
580 int input_open_device(struct input_handle *handle)
581 {
582 struct input_dev *dev = handle->dev;
583 int retval;
584
585 retval = mutex_lock_interruptible(&dev->mutex);
586 if (retval)
587 return retval;
588
589 if (dev->going_away) {
590 retval = -ENODEV;
591 goto out;
592 }
593
594 handle->open++;
595
596 if (!dev->users++ && dev->open)
597 retval = dev->open(dev);
598
599 if (retval) {
600 dev->users--;
601 if (!--handle->open) {
602 /*
603 * Make sure we are not delivering any more events
604 * through this handle
605 */
606 synchronize_rcu();
607 }
608 }
609
610 out:
611 mutex_unlock(&dev->mutex);
612 return retval;
613 }
614 EXPORT_SYMBOL(input_open_device);
615
616 int input_flush_device(struct input_handle *handle, struct file *file)
617 {
618 struct input_dev *dev = handle->dev;
619 int retval;
620
621 retval = mutex_lock_interruptible(&dev->mutex);
622 if (retval)
623 return retval;
624
625 if (dev->flush)
626 retval = dev->flush(dev, file);
627
628 mutex_unlock(&dev->mutex);
629 return retval;
630 }
631 EXPORT_SYMBOL(input_flush_device);
632
633 /**
634 * input_close_device - close input device
635 * @handle: handle through which device is being accessed
636 *
637 * This function should be called by input handlers when they
638 * want to stop receive events from given input device.
639 */
640 void input_close_device(struct input_handle *handle)
641 {
642 struct input_dev *dev = handle->dev;
643
644 mutex_lock(&dev->mutex);
645
646 __input_release_device(handle);
647
648 if (!--dev->users && dev->close)
649 dev->close(dev);
650
651 if (!--handle->open) {
652 /*
653 * synchronize_rcu() makes sure that input_pass_event()
654 * completed and that no more input events are delivered
655 * through this handle
656 */
657 synchronize_rcu();
658 }
659
660 mutex_unlock(&dev->mutex);
661 }
662 EXPORT_SYMBOL(input_close_device);
663
664 /*
665 * Simulate keyup events for all keys that are marked as pressed.
666 * The function must be called with dev->event_lock held.
667 */
668 static void input_dev_release_keys(struct input_dev *dev)
669 {
670 int code;
671
672 if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
673 for (code = 0; code <= KEY_MAX; code++) {
674 if (is_event_supported(code, dev->keybit, KEY_MAX) &&
675 __test_and_clear_bit(code, dev->key)) {
676 input_pass_event(dev, EV_KEY, code, 0);
677 }
678 }
679 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
680 }
681 }
682
683 /*
684 * Prepare device for unregistering
685 */
686 static void input_disconnect_device(struct input_dev *dev)
687 {
688 struct input_handle *handle;
689
690 /*
691 * Mark device as going away. Note that we take dev->mutex here
692 * not to protect access to dev->going_away but rather to ensure
693 * that there are no threads in the middle of input_open_device()
694 */
695 mutex_lock(&dev->mutex);
696 dev->going_away = true;
697 mutex_unlock(&dev->mutex);
698
699 spin_lock_irq(&dev->event_lock);
700
701 /*
702 * Simulate keyup events for all pressed keys so that handlers
703 * are not left with "stuck" keys. The driver may continue
704 * generate events even after we done here but they will not
705 * reach any handlers.
706 */
707 input_dev_release_keys(dev);
708
709 list_for_each_entry(handle, &dev->h_list, d_node)
710 handle->open = 0;
711
712 spin_unlock_irq(&dev->event_lock);
713 }
714
715 /**
716 * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
717 * @ke: keymap entry containing scancode to be converted.
718 * @scancode: pointer to the location where converted scancode should
719 * be stored.
720 *
721 * This function is used to convert scancode stored in &struct keymap_entry
722 * into scalar form understood by legacy keymap handling methods. These
723 * methods expect scancodes to be represented as 'unsigned int'.
724 */
725 int input_scancode_to_scalar(const struct input_keymap_entry *ke,
726 unsigned int *scancode)
727 {
728 switch (ke->len) {
729 case 1:
730 *scancode = *((u8 *)ke->scancode);
731 break;
732
733 case 2:
734 *scancode = *((u16 *)ke->scancode);
735 break;
736
737 case 4:
738 *scancode = *((u32 *)ke->scancode);
739 break;
740
741 default:
742 return -EINVAL;
743 }
744
745 return 0;
746 }
747 EXPORT_SYMBOL(input_scancode_to_scalar);
748
749 /*
750 * Those routines handle the default case where no [gs]etkeycode() is
751 * defined. In this case, an array indexed by the scancode is used.
752 */
753
754 static unsigned int input_fetch_keycode(struct input_dev *dev,
755 unsigned int index)
756 {
757 switch (dev->keycodesize) {
758 case 1:
759 return ((u8 *)dev->keycode)[index];
760
761 case 2:
762 return ((u16 *)dev->keycode)[index];
763
764 default:
765 return ((u32 *)dev->keycode)[index];
766 }
767 }
768
769 static int input_default_getkeycode(struct input_dev *dev,
770 struct input_keymap_entry *ke)
771 {
772 unsigned int index;
773 int error;
774
775 if (!dev->keycodesize)
776 return -EINVAL;
777
778 if (ke->flags & INPUT_KEYMAP_BY_INDEX)
779 index = ke->index;
780 else {
781 error = input_scancode_to_scalar(ke, &index);
782 if (error)
783 return error;
784 }
785
786 if (index >= dev->keycodemax)
787 return -EINVAL;
788
789 ke->keycode = input_fetch_keycode(dev, index);
790 ke->index = index;
791 ke->len = sizeof(index);
792 memcpy(ke->scancode, &index, sizeof(index));
793
794 return 0;
795 }
796
797 static int input_default_setkeycode(struct input_dev *dev,
798 const struct input_keymap_entry *ke,
799 unsigned int *old_keycode)
800 {
801 unsigned int index;
802 int error;
803 int i;
804
805 if (!dev->keycodesize)
806 return -EINVAL;
807
808 if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
809 index = ke->index;
810 } else {
811 error = input_scancode_to_scalar(ke, &index);
812 if (error)
813 return error;
814 }
815
816 if (index >= dev->keycodemax)
817 return -EINVAL;
818
819 if (dev->keycodesize < sizeof(ke->keycode) &&
820 (ke->keycode >> (dev->keycodesize * 8)))
821 return -EINVAL;
822
823 switch (dev->keycodesize) {
824 case 1: {
825 u8 *k = (u8 *)dev->keycode;
826 *old_keycode = k[index];
827 k[index] = ke->keycode;
828 break;
829 }
830 case 2: {
831 u16 *k = (u16 *)dev->keycode;
832 *old_keycode = k[index];
833 k[index] = ke->keycode;
834 break;
835 }
836 default: {
837 u32 *k = (u32 *)dev->keycode;
838 *old_keycode = k[index];
839 k[index] = ke->keycode;
840 break;
841 }
842 }
843
844 __clear_bit(*old_keycode, dev->keybit);
845 __set_bit(ke->keycode, dev->keybit);
846
847 for (i = 0; i < dev->keycodemax; i++) {
848 if (input_fetch_keycode(dev, i) == *old_keycode) {
849 __set_bit(*old_keycode, dev->keybit);
850 break; /* Setting the bit twice is useless, so break */
851 }
852 }
853
854 return 0;
855 }
856
857 /**
858 * input_get_keycode - retrieve keycode currently mapped to a given scancode
859 * @dev: input device which keymap is being queried
860 * @ke: keymap entry
861 *
862 * This function should be called by anyone interested in retrieving current
863 * keymap. Presently evdev handlers use it.
864 */
865 int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
866 {
867 unsigned long flags;
868 int retval;
869
870 spin_lock_irqsave(&dev->event_lock, flags);
871 retval = dev->getkeycode(dev, ke);
872 spin_unlock_irqrestore(&dev->event_lock, flags);
873
874 return retval;
875 }
876 EXPORT_SYMBOL(input_get_keycode);
877
878 /**
879 * input_set_keycode - attribute a keycode to a given scancode
880 * @dev: input device which keymap is being updated
881 * @ke: new keymap entry
882 *
883 * This function should be called by anyone needing to update current
884 * keymap. Presently keyboard and evdev handlers use it.
885 */
886 int input_set_keycode(struct input_dev *dev,
887 const struct input_keymap_entry *ke)
888 {
889 unsigned long flags;
890 unsigned int old_keycode;
891 int retval;
892
893 if (ke->keycode > KEY_MAX)
894 return -EINVAL;
895
896 spin_lock_irqsave(&dev->event_lock, flags);
897
898 retval = dev->setkeycode(dev, ke, &old_keycode);
899 if (retval)
900 goto out;
901
902 /* Make sure KEY_RESERVED did not get enabled. */
903 __clear_bit(KEY_RESERVED, dev->keybit);
904
905 /*
906 * Simulate keyup event if keycode is not present
907 * in the keymap anymore
908 */
909 if (test_bit(EV_KEY, dev->evbit) &&
910 !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
911 __test_and_clear_bit(old_keycode, dev->key)) {
912 struct input_value vals[] = {
913 { EV_KEY, old_keycode, 0 },
914 input_value_sync
915 };
916
917 input_pass_values(dev, vals, ARRAY_SIZE(vals));
918 }
919
920 out:
921 spin_unlock_irqrestore(&dev->event_lock, flags);
922
923 return retval;
924 }
925 EXPORT_SYMBOL(input_set_keycode);
926
927 static const struct input_device_id *input_match_device(struct input_handler *handler,
928 struct input_dev *dev)
929 {
930 const struct input_device_id *id;
931
932 for (id = handler->id_table; id->flags || id->driver_info; id++) {
933
934 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
935 if (id->bustype != dev->id.bustype)
936 continue;
937
938 if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
939 if (id->vendor != dev->id.vendor)
940 continue;
941
942 if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
943 if (id->product != dev->id.product)
944 continue;
945
946 if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
947 if (id->version != dev->id.version)
948 continue;
949
950 if (!bitmap_subset(id->evbit, dev->evbit, EV_MAX))
951 continue;
952
953 if (!bitmap_subset(id->keybit, dev->keybit, KEY_MAX))
954 continue;
955
956 if (!bitmap_subset(id->relbit, dev->relbit, REL_MAX))
957 continue;
958
959 if (!bitmap_subset(id->absbit, dev->absbit, ABS_MAX))
960 continue;
961
962 if (!bitmap_subset(id->mscbit, dev->mscbit, MSC_MAX))
963 continue;
964
965 if (!bitmap_subset(id->ledbit, dev->ledbit, LED_MAX))
966 continue;
967
968 if (!bitmap_subset(id->sndbit, dev->sndbit, SND_MAX))
969 continue;
970
971 if (!bitmap_subset(id->ffbit, dev->ffbit, FF_MAX))
972 continue;
973
974 if (!bitmap_subset(id->swbit, dev->swbit, SW_MAX))
975 continue;
976
977 if (!handler->match || handler->match(handler, dev))
978 return id;
979 }
980
981 return NULL;
982 }
983
984 static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
985 {
986 const struct input_device_id *id;
987 int error;
988
989 id = input_match_device(handler, dev);
990 if (!id)
991 return -ENODEV;
992
993 error = handler->connect(handler, dev, id);
994 if (error && error != -ENODEV)
995 pr_err("failed to attach handler %s to device %s, error: %d\n",
996 handler->name, kobject_name(&dev->dev.kobj), error);
997
998 return error;
999 }
1000
1001 #ifdef CONFIG_COMPAT
1002
1003 static int input_bits_to_string(char *buf, int buf_size,
1004 unsigned long bits, bool skip_empty)
1005 {
1006 int len = 0;
1007
1008 if (INPUT_COMPAT_TEST) {
1009 u32 dword = bits >> 32;
1010 if (dword || !skip_empty)
1011 len += snprintf(buf, buf_size, "%x ", dword);
1012
1013 dword = bits & 0xffffffffUL;
1014 if (dword || !skip_empty || len)
1015 len += snprintf(buf + len, max(buf_size - len, 0),
1016 "%x", dword);
1017 } else {
1018 if (bits || !skip_empty)
1019 len += snprintf(buf, buf_size, "%lx", bits);
1020 }
1021
1022 return len;
1023 }
1024
1025 #else /* !CONFIG_COMPAT */
1026
1027 static int input_bits_to_string(char *buf, int buf_size,
1028 unsigned long bits, bool skip_empty)
1029 {
1030 return bits || !skip_empty ?
1031 snprintf(buf, buf_size, "%lx", bits) : 0;
1032 }
1033
1034 #endif
1035
1036 #ifdef CONFIG_PROC_FS
1037
1038 static struct proc_dir_entry *proc_bus_input_dir;
1039 static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
1040 static int input_devices_state;
1041
1042 static inline void input_wakeup_procfs_readers(void)
1043 {
1044 input_devices_state++;
1045 wake_up(&input_devices_poll_wait);
1046 }
1047
1048 static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
1049 {
1050 poll_wait(file, &input_devices_poll_wait, wait);
1051 if (file->f_version != input_devices_state) {
1052 file->f_version = input_devices_state;
1053 return POLLIN | POLLRDNORM;
1054 }
1055
1056 return 0;
1057 }
1058
1059 union input_seq_state {
1060 struct {
1061 unsigned short pos;
1062 bool mutex_acquired;
1063 };
1064 void *p;
1065 };
1066
1067 static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
1068 {
1069 union input_seq_state *state = (union input_seq_state *)&seq->private;
1070 int error;
1071
1072 /* We need to fit into seq->private pointer */
1073 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1074
1075 error = mutex_lock_interruptible(&input_mutex);
1076 if (error) {
1077 state->mutex_acquired = false;
1078 return ERR_PTR(error);
1079 }
1080
1081 state->mutex_acquired = true;
1082
1083 return seq_list_start(&input_dev_list, *pos);
1084 }
1085
1086 static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1087 {
1088 return seq_list_next(v, &input_dev_list, pos);
1089 }
1090
1091 static void input_seq_stop(struct seq_file *seq, void *v)
1092 {
1093 union input_seq_state *state = (union input_seq_state *)&seq->private;
1094
1095 if (state->mutex_acquired)
1096 mutex_unlock(&input_mutex);
1097 }
1098
1099 static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
1100 unsigned long *bitmap, int max)
1101 {
1102 int i;
1103 bool skip_empty = true;
1104 char buf[18];
1105
1106 seq_printf(seq, "B: %s=", name);
1107
1108 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1109 if (input_bits_to_string(buf, sizeof(buf),
1110 bitmap[i], skip_empty)) {
1111 skip_empty = false;
1112 seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
1113 }
1114 }
1115
1116 /*
1117 * If no output was produced print a single 0.
1118 */
1119 if (skip_empty)
1120 seq_puts(seq, "0");
1121
1122 seq_putc(seq, '\n');
1123 }
1124
1125 static int input_devices_seq_show(struct seq_file *seq, void *v)
1126 {
1127 struct input_dev *dev = container_of(v, struct input_dev, node);
1128 const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1129 struct input_handle *handle;
1130
1131 seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
1132 dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
1133
1134 seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
1135 seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
1136 seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
1137 seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1138 seq_printf(seq, "H: Handlers=");
1139
1140 list_for_each_entry(handle, &dev->h_list, d_node)
1141 seq_printf(seq, "%s ", handle->name);
1142 seq_putc(seq, '\n');
1143
1144 input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
1145
1146 input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
1147 if (test_bit(EV_KEY, dev->evbit))
1148 input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
1149 if (test_bit(EV_REL, dev->evbit))
1150 input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
1151 if (test_bit(EV_ABS, dev->evbit))
1152 input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
1153 if (test_bit(EV_MSC, dev->evbit))
1154 input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
1155 if (test_bit(EV_LED, dev->evbit))
1156 input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
1157 if (test_bit(EV_SND, dev->evbit))
1158 input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
1159 if (test_bit(EV_FF, dev->evbit))
1160 input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
1161 if (test_bit(EV_SW, dev->evbit))
1162 input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
1163
1164 seq_putc(seq, '\n');
1165
1166 kfree(path);
1167 return 0;
1168 }
1169
1170 static const struct seq_operations input_devices_seq_ops = {
1171 .start = input_devices_seq_start,
1172 .next = input_devices_seq_next,
1173 .stop = input_seq_stop,
1174 .show = input_devices_seq_show,
1175 };
1176
1177 static int input_proc_devices_open(struct inode *inode, struct file *file)
1178 {
1179 return seq_open(file, &input_devices_seq_ops);
1180 }
1181
1182 static const struct file_operations input_devices_fileops = {
1183 .owner = THIS_MODULE,
1184 .open = input_proc_devices_open,
1185 .poll = input_proc_devices_poll,
1186 .read = seq_read,
1187 .llseek = seq_lseek,
1188 .release = seq_release,
1189 };
1190
1191 static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
1192 {
1193 union input_seq_state *state = (union input_seq_state *)&seq->private;
1194 int error;
1195
1196 /* We need to fit into seq->private pointer */
1197 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1198
1199 error = mutex_lock_interruptible(&input_mutex);
1200 if (error) {
1201 state->mutex_acquired = false;
1202 return ERR_PTR(error);
1203 }
1204
1205 state->mutex_acquired = true;
1206 state->pos = *pos;
1207
1208 return seq_list_start(&input_handler_list, *pos);
1209 }
1210
1211 static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1212 {
1213 union input_seq_state *state = (union input_seq_state *)&seq->private;
1214
1215 state->pos = *pos + 1;
1216 return seq_list_next(v, &input_handler_list, pos);
1217 }
1218
1219 static int input_handlers_seq_show(struct seq_file *seq, void *v)
1220 {
1221 struct input_handler *handler = container_of(v, struct input_handler, node);
1222 union input_seq_state *state = (union input_seq_state *)&seq->private;
1223
1224 seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
1225 if (handler->filter)
1226 seq_puts(seq, " (filter)");
1227 if (handler->legacy_minors)
1228 seq_printf(seq, " Minor=%d", handler->minor);
1229 seq_putc(seq, '\n');
1230
1231 return 0;
1232 }
1233
1234 static const struct seq_operations input_handlers_seq_ops = {
1235 .start = input_handlers_seq_start,
1236 .next = input_handlers_seq_next,
1237 .stop = input_seq_stop,
1238 .show = input_handlers_seq_show,
1239 };
1240
1241 static int input_proc_handlers_open(struct inode *inode, struct file *file)
1242 {
1243 return seq_open(file, &input_handlers_seq_ops);
1244 }
1245
1246 static const struct file_operations input_handlers_fileops = {
1247 .owner = THIS_MODULE,
1248 .open = input_proc_handlers_open,
1249 .read = seq_read,
1250 .llseek = seq_lseek,
1251 .release = seq_release,
1252 };
1253
1254 static int __init input_proc_init(void)
1255 {
1256 struct proc_dir_entry *entry;
1257
1258 proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1259 if (!proc_bus_input_dir)
1260 return -ENOMEM;
1261
1262 entry = proc_create("devices", 0, proc_bus_input_dir,
1263 &input_devices_fileops);
1264 if (!entry)
1265 goto fail1;
1266
1267 entry = proc_create("handlers", 0, proc_bus_input_dir,
1268 &input_handlers_fileops);
1269 if (!entry)
1270 goto fail2;
1271
1272 return 0;
1273
1274 fail2: remove_proc_entry("devices", proc_bus_input_dir);
1275 fail1: remove_proc_entry("bus/input", NULL);
1276 return -ENOMEM;
1277 }
1278
1279 static void input_proc_exit(void)
1280 {
1281 remove_proc_entry("devices", proc_bus_input_dir);
1282 remove_proc_entry("handlers", proc_bus_input_dir);
1283 remove_proc_entry("bus/input", NULL);
1284 }
1285
1286 #else /* !CONFIG_PROC_FS */
1287 static inline void input_wakeup_procfs_readers(void) { }
1288 static inline int input_proc_init(void) { return 0; }
1289 static inline void input_proc_exit(void) { }
1290 #endif
1291
1292 #define INPUT_DEV_STRING_ATTR_SHOW(name) \
1293 static ssize_t input_dev_show_##name(struct device *dev, \
1294 struct device_attribute *attr, \
1295 char *buf) \
1296 { \
1297 struct input_dev *input_dev = to_input_dev(dev); \
1298 \
1299 return scnprintf(buf, PAGE_SIZE, "%s\n", \
1300 input_dev->name ? input_dev->name : ""); \
1301 } \
1302 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1303
1304 INPUT_DEV_STRING_ATTR_SHOW(name);
1305 INPUT_DEV_STRING_ATTR_SHOW(phys);
1306 INPUT_DEV_STRING_ATTR_SHOW(uniq);
1307
1308 static int input_print_modalias_bits(char *buf, int size,
1309 char name, unsigned long *bm,
1310 unsigned int min_bit, unsigned int max_bit)
1311 {
1312 int len = 0, i;
1313
1314 len += snprintf(buf, max(size, 0), "%c", name);
1315 for (i = min_bit; i < max_bit; i++)
1316 if (bm[BIT_WORD(i)] & BIT_MASK(i))
1317 len += snprintf(buf + len, max(size - len, 0), "%X,", i);
1318 return len;
1319 }
1320
1321 static int input_print_modalias(char *buf, int size, struct input_dev *id,
1322 int add_cr)
1323 {
1324 int len;
1325
1326 len = snprintf(buf, max(size, 0),
1327 "input:b%04Xv%04Xp%04Xe%04X-",
1328 id->id.bustype, id->id.vendor,
1329 id->id.product, id->id.version);
1330
1331 len += input_print_modalias_bits(buf + len, size - len,
1332 'e', id->evbit, 0, EV_MAX);
1333 len += input_print_modalias_bits(buf + len, size - len,
1334 'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1335 len += input_print_modalias_bits(buf + len, size - len,
1336 'r', id->relbit, 0, REL_MAX);
1337 len += input_print_modalias_bits(buf + len, size - len,
1338 'a', id->absbit, 0, ABS_MAX);
1339 len += input_print_modalias_bits(buf + len, size - len,
1340 'm', id->mscbit, 0, MSC_MAX);
1341 len += input_print_modalias_bits(buf + len, size - len,
1342 'l', id->ledbit, 0, LED_MAX);
1343 len += input_print_modalias_bits(buf + len, size - len,
1344 's', id->sndbit, 0, SND_MAX);
1345 len += input_print_modalias_bits(buf + len, size - len,
1346 'f', id->ffbit, 0, FF_MAX);
1347 len += input_print_modalias_bits(buf + len, size - len,
1348 'w', id->swbit, 0, SW_MAX);
1349
1350 if (add_cr)
1351 len += snprintf(buf + len, max(size - len, 0), "\n");
1352
1353 return len;
1354 }
1355
1356 static ssize_t input_dev_show_modalias(struct device *dev,
1357 struct device_attribute *attr,
1358 char *buf)
1359 {
1360 struct input_dev *id = to_input_dev(dev);
1361 ssize_t len;
1362
1363 len = input_print_modalias(buf, PAGE_SIZE, id, 1);
1364
1365 return min_t(int, len, PAGE_SIZE);
1366 }
1367 static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1368
1369 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1370 int max, int add_cr);
1371
1372 static ssize_t input_dev_show_properties(struct device *dev,
1373 struct device_attribute *attr,
1374 char *buf)
1375 {
1376 struct input_dev *input_dev = to_input_dev(dev);
1377 int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
1378 INPUT_PROP_MAX, true);
1379 return min_t(int, len, PAGE_SIZE);
1380 }
1381 static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
1382
1383 static struct attribute *input_dev_attrs[] = {
1384 &dev_attr_name.attr,
1385 &dev_attr_phys.attr,
1386 &dev_attr_uniq.attr,
1387 &dev_attr_modalias.attr,
1388 &dev_attr_properties.attr,
1389 NULL
1390 };
1391
1392 static struct attribute_group input_dev_attr_group = {
1393 .attrs = input_dev_attrs,
1394 };
1395
1396 #define INPUT_DEV_ID_ATTR(name) \
1397 static ssize_t input_dev_show_id_##name(struct device *dev, \
1398 struct device_attribute *attr, \
1399 char *buf) \
1400 { \
1401 struct input_dev *input_dev = to_input_dev(dev); \
1402 return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name); \
1403 } \
1404 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1405
1406 INPUT_DEV_ID_ATTR(bustype);
1407 INPUT_DEV_ID_ATTR(vendor);
1408 INPUT_DEV_ID_ATTR(product);
1409 INPUT_DEV_ID_ATTR(version);
1410
1411 static struct attribute *input_dev_id_attrs[] = {
1412 &dev_attr_bustype.attr,
1413 &dev_attr_vendor.attr,
1414 &dev_attr_product.attr,
1415 &dev_attr_version.attr,
1416 NULL
1417 };
1418
1419 static struct attribute_group input_dev_id_attr_group = {
1420 .name = "id",
1421 .attrs = input_dev_id_attrs,
1422 };
1423
1424 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1425 int max, int add_cr)
1426 {
1427 int i;
1428 int len = 0;
1429 bool skip_empty = true;
1430
1431 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1432 len += input_bits_to_string(buf + len, max(buf_size - len, 0),
1433 bitmap[i], skip_empty);
1434 if (len) {
1435 skip_empty = false;
1436 if (i > 0)
1437 len += snprintf(buf + len, max(buf_size - len, 0), " ");
1438 }
1439 }
1440
1441 /*
1442 * If no output was produced print a single 0.
1443 */
1444 if (len == 0)
1445 len = snprintf(buf, buf_size, "%d", 0);
1446
1447 if (add_cr)
1448 len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1449
1450 return len;
1451 }
1452
1453 #define INPUT_DEV_CAP_ATTR(ev, bm) \
1454 static ssize_t input_dev_show_cap_##bm(struct device *dev, \
1455 struct device_attribute *attr, \
1456 char *buf) \
1457 { \
1458 struct input_dev *input_dev = to_input_dev(dev); \
1459 int len = input_print_bitmap(buf, PAGE_SIZE, \
1460 input_dev->bm##bit, ev##_MAX, \
1461 true); \
1462 return min_t(int, len, PAGE_SIZE); \
1463 } \
1464 static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1465
1466 INPUT_DEV_CAP_ATTR(EV, ev);
1467 INPUT_DEV_CAP_ATTR(KEY, key);
1468 INPUT_DEV_CAP_ATTR(REL, rel);
1469 INPUT_DEV_CAP_ATTR(ABS, abs);
1470 INPUT_DEV_CAP_ATTR(MSC, msc);
1471 INPUT_DEV_CAP_ATTR(LED, led);
1472 INPUT_DEV_CAP_ATTR(SND, snd);
1473 INPUT_DEV_CAP_ATTR(FF, ff);
1474 INPUT_DEV_CAP_ATTR(SW, sw);
1475
1476 static struct attribute *input_dev_caps_attrs[] = {
1477 &dev_attr_ev.attr,
1478 &dev_attr_key.attr,
1479 &dev_attr_rel.attr,
1480 &dev_attr_abs.attr,
1481 &dev_attr_msc.attr,
1482 &dev_attr_led.attr,
1483 &dev_attr_snd.attr,
1484 &dev_attr_ff.attr,
1485 &dev_attr_sw.attr,
1486 NULL
1487 };
1488
1489 static struct attribute_group input_dev_caps_attr_group = {
1490 .name = "capabilities",
1491 .attrs = input_dev_caps_attrs,
1492 };
1493
1494 static const struct attribute_group *input_dev_attr_groups[] = {
1495 &input_dev_attr_group,
1496 &input_dev_id_attr_group,
1497 &input_dev_caps_attr_group,
1498 NULL
1499 };
1500
1501 static void input_dev_release(struct device *device)
1502 {
1503 struct input_dev *dev = to_input_dev(device);
1504
1505 input_ff_destroy(dev);
1506 input_mt_destroy_slots(dev);
1507 kfree(dev->absinfo);
1508 kfree(dev->vals);
1509 kfree(dev);
1510
1511 module_put(THIS_MODULE);
1512 }
1513
1514 /*
1515 * Input uevent interface - loading event handlers based on
1516 * device bitfields.
1517 */
1518 static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1519 const char *name, unsigned long *bitmap, int max)
1520 {
1521 int len;
1522
1523 if (add_uevent_var(env, "%s", name))
1524 return -ENOMEM;
1525
1526 len = input_print_bitmap(&env->buf[env->buflen - 1],
1527 sizeof(env->buf) - env->buflen,
1528 bitmap, max, false);
1529 if (len >= (sizeof(env->buf) - env->buflen))
1530 return -ENOMEM;
1531
1532 env->buflen += len;
1533 return 0;
1534 }
1535
1536 static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1537 struct input_dev *dev)
1538 {
1539 int len;
1540
1541 if (add_uevent_var(env, "MODALIAS="))
1542 return -ENOMEM;
1543
1544 len = input_print_modalias(&env->buf[env->buflen - 1],
1545 sizeof(env->buf) - env->buflen,
1546 dev, 0);
1547 if (len >= (sizeof(env->buf) - env->buflen))
1548 return -ENOMEM;
1549
1550 env->buflen += len;
1551 return 0;
1552 }
1553
1554 #define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \
1555 do { \
1556 int err = add_uevent_var(env, fmt, val); \
1557 if (err) \
1558 return err; \
1559 } while (0)
1560
1561 #define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max) \
1562 do { \
1563 int err = input_add_uevent_bm_var(env, name, bm, max); \
1564 if (err) \
1565 return err; \
1566 } while (0)
1567
1568 #define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \
1569 do { \
1570 int err = input_add_uevent_modalias_var(env, dev); \
1571 if (err) \
1572 return err; \
1573 } while (0)
1574
1575 static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
1576 {
1577 struct input_dev *dev = to_input_dev(device);
1578
1579 INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1580 dev->id.bustype, dev->id.vendor,
1581 dev->id.product, dev->id.version);
1582 if (dev->name)
1583 INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1584 if (dev->phys)
1585 INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1586 if (dev->uniq)
1587 INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1588
1589 INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
1590
1591 INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1592 if (test_bit(EV_KEY, dev->evbit))
1593 INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1594 if (test_bit(EV_REL, dev->evbit))
1595 INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1596 if (test_bit(EV_ABS, dev->evbit))
1597 INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1598 if (test_bit(EV_MSC, dev->evbit))
1599 INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1600 if (test_bit(EV_LED, dev->evbit))
1601 INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1602 if (test_bit(EV_SND, dev->evbit))
1603 INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1604 if (test_bit(EV_FF, dev->evbit))
1605 INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1606 if (test_bit(EV_SW, dev->evbit))
1607 INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1608
1609 INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1610
1611 return 0;
1612 }
1613
1614 #define INPUT_DO_TOGGLE(dev, type, bits, on) \
1615 do { \
1616 int i; \
1617 bool active; \
1618 \
1619 if (!test_bit(EV_##type, dev->evbit)) \
1620 break; \
1621 \
1622 for (i = 0; i < type##_MAX; i++) { \
1623 if (!test_bit(i, dev->bits##bit)) \
1624 continue; \
1625 \
1626 active = test_bit(i, dev->bits); \
1627 if (!active && !on) \
1628 continue; \
1629 \
1630 dev->event(dev, EV_##type, i, on ? active : 0); \
1631 } \
1632 } while (0)
1633
1634 static void input_dev_toggle(struct input_dev *dev, bool activate)
1635 {
1636 if (!dev->event)
1637 return;
1638
1639 INPUT_DO_TOGGLE(dev, LED, led, activate);
1640 INPUT_DO_TOGGLE(dev, SND, snd, activate);
1641
1642 if (activate && test_bit(EV_REP, dev->evbit)) {
1643 dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1644 dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1645 }
1646 }
1647
1648 /**
1649 * input_reset_device() - reset/restore the state of input device
1650 * @dev: input device whose state needs to be reset
1651 *
1652 * This function tries to reset the state of an opened input device and
1653 * bring internal state and state if the hardware in sync with each other.
1654 * We mark all keys as released, restore LED state, repeat rate, etc.
1655 */
1656 void input_reset_device(struct input_dev *dev)
1657 {
1658 mutex_lock(&dev->mutex);
1659
1660 if (dev->users) {
1661 input_dev_toggle(dev, true);
1662
1663 /*
1664 * Keys that have been pressed at suspend time are unlikely
1665 * to be still pressed when we resume.
1666 */
1667 spin_lock_irq(&dev->event_lock);
1668 input_dev_release_keys(dev);
1669 spin_unlock_irq(&dev->event_lock);
1670 }
1671
1672 mutex_unlock(&dev->mutex);
1673 }
1674 EXPORT_SYMBOL(input_reset_device);
1675
1676 #ifdef CONFIG_PM
1677 static int input_dev_suspend(struct device *dev)
1678 {
1679 struct input_dev *input_dev = to_input_dev(dev);
1680
1681 mutex_lock(&input_dev->mutex);
1682
1683 if (input_dev->users)
1684 input_dev_toggle(input_dev, false);
1685
1686 mutex_unlock(&input_dev->mutex);
1687
1688 return 0;
1689 }
1690
1691 static int input_dev_resume(struct device *dev)
1692 {
1693 struct input_dev *input_dev = to_input_dev(dev);
1694
1695 input_reset_device(input_dev);
1696
1697 return 0;
1698 }
1699
1700 static const struct dev_pm_ops input_dev_pm_ops = {
1701 .suspend = input_dev_suspend,
1702 .resume = input_dev_resume,
1703 .poweroff = input_dev_suspend,
1704 .restore = input_dev_resume,
1705 };
1706 #endif /* CONFIG_PM */
1707
1708 static struct device_type input_dev_type = {
1709 .groups = input_dev_attr_groups,
1710 .release = input_dev_release,
1711 .uevent = input_dev_uevent,
1712 #ifdef CONFIG_PM
1713 .pm = &input_dev_pm_ops,
1714 #endif
1715 };
1716
1717 static char *input_devnode(struct device *dev, umode_t *mode)
1718 {
1719 return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
1720 }
1721
1722 struct class input_class = {
1723 .name = "input",
1724 .devnode = input_devnode,
1725 };
1726 EXPORT_SYMBOL_GPL(input_class);
1727
1728 /**
1729 * input_allocate_device - allocate memory for new input device
1730 *
1731 * Returns prepared struct input_dev or %NULL.
1732 *
1733 * NOTE: Use input_free_device() to free devices that have not been
1734 * registered; input_unregister_device() should be used for already
1735 * registered devices.
1736 */
1737 struct input_dev *input_allocate_device(void)
1738 {
1739 static atomic_t input_no = ATOMIC_INIT(0);
1740 struct input_dev *dev;
1741
1742 dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
1743 if (dev) {
1744 dev->dev.type = &input_dev_type;
1745 dev->dev.class = &input_class;
1746 device_initialize(&dev->dev);
1747 mutex_init(&dev->mutex);
1748 spin_lock_init(&dev->event_lock);
1749 init_timer(&dev->timer);
1750 INIT_LIST_HEAD(&dev->h_list);
1751 INIT_LIST_HEAD(&dev->node);
1752
1753 dev_set_name(&dev->dev, "input%ld",
1754 (unsigned long) atomic_inc_return(&input_no) - 1);
1755
1756 __module_get(THIS_MODULE);
1757 }
1758
1759 return dev;
1760 }
1761 EXPORT_SYMBOL(input_allocate_device);
1762
1763 struct input_devres {
1764 struct input_dev *input;
1765 };
1766
1767 static int devm_input_device_match(struct device *dev, void *res, void *data)
1768 {
1769 struct input_devres *devres = res;
1770
1771 return devres->input == data;
1772 }
1773
1774 static void devm_input_device_release(struct device *dev, void *res)
1775 {
1776 struct input_devres *devres = res;
1777 struct input_dev *input = devres->input;
1778
1779 dev_dbg(dev, "%s: dropping reference to %s\n",
1780 __func__, dev_name(&input->dev));
1781 input_put_device(input);
1782 }
1783
1784 /**
1785 * devm_input_allocate_device - allocate managed input device
1786 * @dev: device owning the input device being created
1787 *
1788 * Returns prepared struct input_dev or %NULL.
1789 *
1790 * Managed input devices do not need to be explicitly unregistered or
1791 * freed as it will be done automatically when owner device unbinds from
1792 * its driver (or binding fails). Once managed input device is allocated,
1793 * it is ready to be set up and registered in the same fashion as regular
1794 * input device. There are no special devm_input_device_[un]register()
1795 * variants, regular ones work with both managed and unmanaged devices,
1796 * should you need them. In most cases however, managed input device need
1797 * not be explicitly unregistered or freed.
1798 *
1799 * NOTE: the owner device is set up as parent of input device and users
1800 * should not override it.
1801 */
1802 struct input_dev *devm_input_allocate_device(struct device *dev)
1803 {
1804 struct input_dev *input;
1805 struct input_devres *devres;
1806
1807 devres = devres_alloc(devm_input_device_release,
1808 sizeof(struct input_devres), GFP_KERNEL);
1809 if (!devres)
1810 return NULL;
1811
1812 input = input_allocate_device();
1813 if (!input) {
1814 devres_free(devres);
1815 return NULL;
1816 }
1817
1818 input->dev.parent = dev;
1819 input->devres_managed = true;
1820
1821 devres->input = input;
1822 devres_add(dev, devres);
1823
1824 return input;
1825 }
1826 EXPORT_SYMBOL(devm_input_allocate_device);
1827
1828 /**
1829 * input_free_device - free memory occupied by input_dev structure
1830 * @dev: input device to free
1831 *
1832 * This function should only be used if input_register_device()
1833 * was not called yet or if it failed. Once device was registered
1834 * use input_unregister_device() and memory will be freed once last
1835 * reference to the device is dropped.
1836 *
1837 * Device should be allocated by input_allocate_device().
1838 *
1839 * NOTE: If there are references to the input device then memory
1840 * will not be freed until last reference is dropped.
1841 */
1842 void input_free_device(struct input_dev *dev)
1843 {
1844 if (dev) {
1845 if (dev->devres_managed)
1846 WARN_ON(devres_destroy(dev->dev.parent,
1847 devm_input_device_release,
1848 devm_input_device_match,
1849 dev));
1850 input_put_device(dev);
1851 }
1852 }
1853 EXPORT_SYMBOL(input_free_device);
1854
1855 /**
1856 * input_set_capability - mark device as capable of a certain event
1857 * @dev: device that is capable of emitting or accepting event
1858 * @type: type of the event (EV_KEY, EV_REL, etc...)
1859 * @code: event code
1860 *
1861 * In addition to setting up corresponding bit in appropriate capability
1862 * bitmap the function also adjusts dev->evbit.
1863 */
1864 void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
1865 {
1866 switch (type) {
1867 case EV_KEY:
1868 __set_bit(code, dev->keybit);
1869 break;
1870
1871 case EV_REL:
1872 __set_bit(code, dev->relbit);
1873 break;
1874
1875 case EV_ABS:
1876 input_alloc_absinfo(dev);
1877 if (!dev->absinfo)
1878 return;
1879
1880 __set_bit(code, dev->absbit);
1881 break;
1882
1883 case EV_MSC:
1884 __set_bit(code, dev->mscbit);
1885 break;
1886
1887 case EV_SW:
1888 __set_bit(code, dev->swbit);
1889 break;
1890
1891 case EV_LED:
1892 __set_bit(code, dev->ledbit);
1893 break;
1894
1895 case EV_SND:
1896 __set_bit(code, dev->sndbit);
1897 break;
1898
1899 case EV_FF:
1900 __set_bit(code, dev->ffbit);
1901 break;
1902
1903 case EV_PWR:
1904 /* do nothing */
1905 break;
1906
1907 default:
1908 pr_err("input_set_capability: unknown type %u (code %u)\n",
1909 type, code);
1910 dump_stack();
1911 return;
1912 }
1913
1914 __set_bit(type, dev->evbit);
1915 }
1916 EXPORT_SYMBOL(input_set_capability);
1917
1918 static unsigned int input_estimate_events_per_packet(struct input_dev *dev)
1919 {
1920 int mt_slots;
1921 int i;
1922 unsigned int events;
1923
1924 if (dev->mt) {
1925 mt_slots = dev->mt->num_slots;
1926 } else if (test_bit(ABS_MT_TRACKING_ID, dev->absbit)) {
1927 mt_slots = dev->absinfo[ABS_MT_TRACKING_ID].maximum -
1928 dev->absinfo[ABS_MT_TRACKING_ID].minimum + 1,
1929 mt_slots = clamp(mt_slots, 2, 32);
1930 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
1931 mt_slots = 2;
1932 } else {
1933 mt_slots = 0;
1934 }
1935
1936 events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */
1937
1938 for (i = 0; i < ABS_CNT; i++) {
1939 if (test_bit(i, dev->absbit)) {
1940 if (input_is_mt_axis(i))
1941 events += mt_slots;
1942 else
1943 events++;
1944 }
1945 }
1946
1947 for (i = 0; i < REL_CNT; i++)
1948 if (test_bit(i, dev->relbit))
1949 events++;
1950
1951 /* Make room for KEY and MSC events */
1952 events += 7;
1953
1954 return events;
1955 }
1956
1957 #define INPUT_CLEANSE_BITMASK(dev, type, bits) \
1958 do { \
1959 if (!test_bit(EV_##type, dev->evbit)) \
1960 memset(dev->bits##bit, 0, \
1961 sizeof(dev->bits##bit)); \
1962 } while (0)
1963
1964 static void input_cleanse_bitmasks(struct input_dev *dev)
1965 {
1966 INPUT_CLEANSE_BITMASK(dev, KEY, key);
1967 INPUT_CLEANSE_BITMASK(dev, REL, rel);
1968 INPUT_CLEANSE_BITMASK(dev, ABS, abs);
1969 INPUT_CLEANSE_BITMASK(dev, MSC, msc);
1970 INPUT_CLEANSE_BITMASK(dev, LED, led);
1971 INPUT_CLEANSE_BITMASK(dev, SND, snd);
1972 INPUT_CLEANSE_BITMASK(dev, FF, ff);
1973 INPUT_CLEANSE_BITMASK(dev, SW, sw);
1974 }
1975
1976 static void __input_unregister_device(struct input_dev *dev)
1977 {
1978 struct input_handle *handle, *next;
1979
1980 input_disconnect_device(dev);
1981
1982 mutex_lock(&input_mutex);
1983
1984 list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
1985 handle->handler->disconnect(handle);
1986 WARN_ON(!list_empty(&dev->h_list));
1987
1988 del_timer_sync(&dev->timer);
1989 list_del_init(&dev->node);
1990
1991 input_wakeup_procfs_readers();
1992
1993 mutex_unlock(&input_mutex);
1994
1995 device_del(&dev->dev);
1996 }
1997
1998 static void devm_input_device_unregister(struct device *dev, void *res)
1999 {
2000 struct input_devres *devres = res;
2001 struct input_dev *input = devres->input;
2002
2003 dev_dbg(dev, "%s: unregistering device %s\n",
2004 __func__, dev_name(&input->dev));
2005 __input_unregister_device(input);
2006 }
2007
2008 /**
2009 * input_register_device - register device with input core
2010 * @dev: device to be registered
2011 *
2012 * This function registers device with input core. The device must be
2013 * allocated with input_allocate_device() and all it's capabilities
2014 * set up before registering.
2015 * If function fails the device must be freed with input_free_device().
2016 * Once device has been successfully registered it can be unregistered
2017 * with input_unregister_device(); input_free_device() should not be
2018 * called in this case.
2019 *
2020 * Note that this function is also used to register managed input devices
2021 * (ones allocated with devm_input_allocate_device()). Such managed input
2022 * devices need not be explicitly unregistered or freed, their tear down
2023 * is controlled by the devres infrastructure. It is also worth noting
2024 * that tear down of managed input devices is internally a 2-step process:
2025 * registered managed input device is first unregistered, but stays in
2026 * memory and can still handle input_event() calls (although events will
2027 * not be delivered anywhere). The freeing of managed input device will
2028 * happen later, when devres stack is unwound to the point where device
2029 * allocation was made.
2030 */
2031 int input_register_device(struct input_dev *dev)
2032 {
2033 struct input_devres *devres = NULL;
2034 struct input_handler *handler;
2035 unsigned int packet_size;
2036 const char *path;
2037 int error;
2038
2039 if (dev->devres_managed) {
2040 devres = devres_alloc(devm_input_device_unregister,
2041 sizeof(struct input_devres), GFP_KERNEL);
2042 if (!devres)
2043 return -ENOMEM;
2044
2045 devres->input = dev;
2046 }
2047
2048 /* Every input device generates EV_SYN/SYN_REPORT events. */
2049 __set_bit(EV_SYN, dev->evbit);
2050
2051 /* KEY_RESERVED is not supposed to be transmitted to userspace. */
2052 __clear_bit(KEY_RESERVED, dev->keybit);
2053
2054 /* Make sure that bitmasks not mentioned in dev->evbit are clean. */
2055 input_cleanse_bitmasks(dev);
2056
2057 packet_size = input_estimate_events_per_packet(dev);
2058 if (dev->hint_events_per_packet < packet_size)
2059 dev->hint_events_per_packet = packet_size;
2060
2061 dev->max_vals = max(dev->hint_events_per_packet, packet_size) + 2;
2062 dev->vals = kcalloc(dev->max_vals, sizeof(*dev->vals), GFP_KERNEL);
2063 if (!dev->vals) {
2064 error = -ENOMEM;
2065 goto err_devres_free;
2066 }
2067
2068 /*
2069 * If delay and period are pre-set by the driver, then autorepeating
2070 * is handled by the driver itself and we don't do it in input.c.
2071 */
2072 if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
2073 dev->timer.data = (long) dev;
2074 dev->timer.function = input_repeat_key;
2075 dev->rep[REP_DELAY] = 250;
2076 dev->rep[REP_PERIOD] = 33;
2077 }
2078
2079 if (!dev->getkeycode)
2080 dev->getkeycode = input_default_getkeycode;
2081
2082 if (!dev->setkeycode)
2083 dev->setkeycode = input_default_setkeycode;
2084
2085 error = device_add(&dev->dev);
2086 if (error)
2087 goto err_free_vals;
2088
2089 path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
2090 pr_info("%s as %s\n",
2091 dev->name ? dev->name : "Unspecified device",
2092 path ? path : "N/A");
2093 kfree(path);
2094
2095 error = mutex_lock_interruptible(&input_mutex);
2096 if (error)
2097 goto err_device_del;
2098
2099 list_add_tail(&dev->node, &input_dev_list);
2100
2101 list_for_each_entry(handler, &input_handler_list, node)
2102 input_attach_handler(dev, handler);
2103
2104 input_wakeup_procfs_readers();
2105
2106 mutex_unlock(&input_mutex);
2107
2108 if (dev->devres_managed) {
2109 dev_dbg(dev->dev.parent, "%s: registering %s with devres.\n",
2110 __func__, dev_name(&dev->dev));
2111 devres_add(dev->dev.parent, devres);
2112 }
2113 return 0;
2114
2115 err_device_del:
2116 device_del(&dev->dev);
2117 err_free_vals:
2118 kfree(dev->vals);
2119 dev->vals = NULL;
2120 err_devres_free:
2121 devres_free(devres);
2122 return error;
2123 }
2124 EXPORT_SYMBOL(input_register_device);
2125
2126 /**
2127 * input_unregister_device - unregister previously registered device
2128 * @dev: device to be unregistered
2129 *
2130 * This function unregisters an input device. Once device is unregistered
2131 * the caller should not try to access it as it may get freed at any moment.
2132 */
2133 void input_unregister_device(struct input_dev *dev)
2134 {
2135 if (dev->devres_managed) {
2136 WARN_ON(devres_destroy(dev->dev.parent,
2137 devm_input_device_unregister,
2138 devm_input_device_match,
2139 dev));
2140 __input_unregister_device(dev);
2141 /*
2142 * We do not do input_put_device() here because it will be done
2143 * when 2nd devres fires up.
2144 */
2145 } else {
2146 __input_unregister_device(dev);
2147 input_put_device(dev);
2148 }
2149 }
2150 EXPORT_SYMBOL(input_unregister_device);
2151
2152 /**
2153 * input_register_handler - register a new input handler
2154 * @handler: handler to be registered
2155 *
2156 * This function registers a new input handler (interface) for input
2157 * devices in the system and attaches it to all input devices that
2158 * are compatible with the handler.
2159 */
2160 int input_register_handler(struct input_handler *handler)
2161 {
2162 struct input_dev *dev;
2163 int error;
2164
2165 error = mutex_lock_interruptible(&input_mutex);
2166 if (error)
2167 return error;
2168
2169 INIT_LIST_HEAD(&handler->h_list);
2170
2171 list_add_tail(&handler->node, &input_handler_list);
2172
2173 list_for_each_entry(dev, &input_dev_list, node)
2174 input_attach_handler(dev, handler);
2175
2176 input_wakeup_procfs_readers();
2177
2178 mutex_unlock(&input_mutex);
2179 return 0;
2180 }
2181 EXPORT_SYMBOL(input_register_handler);
2182
2183 /**
2184 * input_unregister_handler - unregisters an input handler
2185 * @handler: handler to be unregistered
2186 *
2187 * This function disconnects a handler from its input devices and
2188 * removes it from lists of known handlers.
2189 */
2190 void input_unregister_handler(struct input_handler *handler)
2191 {
2192 struct input_handle *handle, *next;
2193
2194 mutex_lock(&input_mutex);
2195
2196 list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
2197 handler->disconnect(handle);
2198 WARN_ON(!list_empty(&handler->h_list));
2199
2200 list_del_init(&handler->node);
2201
2202 input_wakeup_procfs_readers();
2203
2204 mutex_unlock(&input_mutex);
2205 }
2206 EXPORT_SYMBOL(input_unregister_handler);
2207
2208 /**
2209 * input_handler_for_each_handle - handle iterator
2210 * @handler: input handler to iterate
2211 * @data: data for the callback
2212 * @fn: function to be called for each handle
2213 *
2214 * Iterate over @bus's list of devices, and call @fn for each, passing
2215 * it @data and stop when @fn returns a non-zero value. The function is
2216 * using RCU to traverse the list and therefore may be usind in atonic
2217 * contexts. The @fn callback is invoked from RCU critical section and
2218 * thus must not sleep.
2219 */
2220 int input_handler_for_each_handle(struct input_handler *handler, void *data,
2221 int (*fn)(struct input_handle *, void *))
2222 {
2223 struct input_handle *handle;
2224 int retval = 0;
2225
2226 rcu_read_lock();
2227
2228 list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
2229 retval = fn(handle, data);
2230 if (retval)
2231 break;
2232 }
2233
2234 rcu_read_unlock();
2235
2236 return retval;
2237 }
2238 EXPORT_SYMBOL(input_handler_for_each_handle);
2239
2240 /**
2241 * input_register_handle - register a new input handle
2242 * @handle: handle to register
2243 *
2244 * This function puts a new input handle onto device's
2245 * and handler's lists so that events can flow through
2246 * it once it is opened using input_open_device().
2247 *
2248 * This function is supposed to be called from handler's
2249 * connect() method.
2250 */
2251 int input_register_handle(struct input_handle *handle)
2252 {
2253 struct input_handler *handler = handle->handler;
2254 struct input_dev *dev = handle->dev;
2255 int error;
2256
2257 /*
2258 * We take dev->mutex here to prevent race with
2259 * input_release_device().
2260 */
2261 error = mutex_lock_interruptible(&dev->mutex);
2262 if (error)
2263 return error;
2264
2265 /*
2266 * Filters go to the head of the list, normal handlers
2267 * to the tail.
2268 */
2269 if (handler->filter)
2270 list_add_rcu(&handle->d_node, &dev->h_list);
2271 else
2272 list_add_tail_rcu(&handle->d_node, &dev->h_list);
2273
2274 mutex_unlock(&dev->mutex);
2275
2276 /*
2277 * Since we are supposed to be called from ->connect()
2278 * which is mutually exclusive with ->disconnect()
2279 * we can't be racing with input_unregister_handle()
2280 * and so separate lock is not needed here.
2281 */
2282 list_add_tail_rcu(&handle->h_node, &handler->h_list);
2283
2284 if (handler->start)
2285 handler->start(handle);
2286
2287 return 0;
2288 }
2289 EXPORT_SYMBOL(input_register_handle);
2290
2291 /**
2292 * input_unregister_handle - unregister an input handle
2293 * @handle: handle to unregister
2294 *
2295 * This function removes input handle from device's
2296 * and handler's lists.
2297 *
2298 * This function is supposed to be called from handler's
2299 * disconnect() method.
2300 */
2301 void input_unregister_handle(struct input_handle *handle)
2302 {
2303 struct input_dev *dev = handle->dev;
2304
2305 list_del_rcu(&handle->h_node);
2306
2307 /*
2308 * Take dev->mutex to prevent race with input_release_device().
2309 */
2310 mutex_lock(&dev->mutex);
2311 list_del_rcu(&handle->d_node);
2312 mutex_unlock(&dev->mutex);
2313
2314 synchronize_rcu();
2315 }
2316 EXPORT_SYMBOL(input_unregister_handle);
2317
2318 /**
2319 * input_get_new_minor - allocates a new input minor number
2320 * @legacy_base: beginning or the legacy range to be searched
2321 * @legacy_num: size of legacy range
2322 * @allow_dynamic: whether we can also take ID from the dynamic range
2323 *
2324 * This function allocates a new device minor for from input major namespace.
2325 * Caller can request legacy minor by specifying @legacy_base and @legacy_num
2326 * parameters and whether ID can be allocated from dynamic range if there are
2327 * no free IDs in legacy range.
2328 */
2329 int input_get_new_minor(int legacy_base, unsigned int legacy_num,
2330 bool allow_dynamic)
2331 {
2332 /*
2333 * This function should be called from input handler's ->connect()
2334 * methods, which are serialized with input_mutex, so no additional
2335 * locking is needed here.
2336 */
2337 if (legacy_base >= 0) {
2338 int minor = ida_simple_get(&input_ida,
2339 legacy_base,
2340 legacy_base + legacy_num,
2341 GFP_KERNEL);
2342 if (minor >= 0 || !allow_dynamic)
2343 return minor;
2344 }
2345
2346 return ida_simple_get(&input_ida,
2347 INPUT_FIRST_DYNAMIC_DEV, INPUT_MAX_CHAR_DEVICES,
2348 GFP_KERNEL);
2349 }
2350 EXPORT_SYMBOL(input_get_new_minor);
2351
2352 /**
2353 * input_free_minor - release previously allocated minor
2354 * @minor: minor to be released
2355 *
2356 * This function releases previously allocated input minor so that it can be
2357 * reused later.
2358 */
2359 void input_free_minor(unsigned int minor)
2360 {
2361 ida_simple_remove(&input_ida, minor);
2362 }
2363 EXPORT_SYMBOL(input_free_minor);
2364
2365 static int __init input_init(void)
2366 {
2367 int err;
2368
2369 err = class_register(&input_class);
2370 if (err) {
2371 pr_err("unable to register input_dev class\n");
2372 return err;
2373 }
2374
2375 err = input_proc_init();
2376 if (err)
2377 goto fail1;
2378
2379 err = register_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2380 INPUT_MAX_CHAR_DEVICES, "input");
2381 if (err) {
2382 pr_err("unable to register char major %d", INPUT_MAJOR);
2383 goto fail2;
2384 }
2385
2386 return 0;
2387
2388 fail2: input_proc_exit();
2389 fail1: class_unregister(&input_class);
2390 return err;
2391 }
2392
2393 static void __exit input_exit(void)
2394 {
2395 input_proc_exit();
2396 unregister_chrdev_region(MKDEV(INPUT_MAJOR, 0),
2397 INPUT_MAX_CHAR_DEVICES);
2398 class_unregister(&input_class);
2399 }
2400
2401 subsys_initcall(input_init);
2402 module_exit(input_exit);
Linux with added FPC-III support