Merge branch 'firewire-kernel-streaming' of git://git.alsa-project.org/alsa-kprivate
[firewire-audio.git] / drivers / input / input.c
blob11905b6a30237c574825a178b16b8fde32d593dd
1 /*
2 * The input core
4 * Copyright (c) 1999-2002 Vojtech Pavlik
5 */
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.
13 #define pr_fmt(fmt) KBUILD_BASENAME ": " fmt
15 #include <linux/init.h>
16 #include <linux/types.h>
17 #include <linux/input/mt.h>
18 #include <linux/module.h>
19 #include <linux/slab.h>
20 #include <linux/random.h>
21 #include <linux/major.h>
22 #include <linux/proc_fs.h>
23 #include <linux/sched.h>
24 #include <linux/seq_file.h>
25 #include <linux/poll.h>
26 #include <linux/device.h>
27 #include <linux/mutex.h>
28 #include <linux/rcupdate.h>
29 #include "input-compat.h"
31 MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
32 MODULE_DESCRIPTION("Input core");
33 MODULE_LICENSE("GPL");
35 #define INPUT_DEVICES 256
37 static LIST_HEAD(input_dev_list);
38 static LIST_HEAD(input_handler_list);
41 * input_mutex protects access to both input_dev_list and input_handler_list.
42 * This also causes input_[un]register_device and input_[un]register_handler
43 * be mutually exclusive which simplifies locking in drivers implementing
44 * input handlers.
46 static DEFINE_MUTEX(input_mutex);
48 static struct input_handler *input_table[8];
50 static inline int is_event_supported(unsigned int code,
51 unsigned long *bm, unsigned int max)
53 return code <= max && test_bit(code, bm);
56 static int input_defuzz_abs_event(int value, int old_val, int fuzz)
58 if (fuzz) {
59 if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
60 return old_val;
62 if (value > old_val - fuzz && value < old_val + fuzz)
63 return (old_val * 3 + value) / 4;
65 if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
66 return (old_val + value) / 2;
69 return value;
73 * Pass event first through all filters and then, if event has not been
74 * filtered out, through all open handles. This function is called with
75 * dev->event_lock held and interrupts disabled.
77 static void input_pass_event(struct input_dev *dev,
78 unsigned int type, unsigned int code, int value)
80 struct input_handler *handler;
81 struct input_handle *handle;
83 rcu_read_lock();
85 handle = rcu_dereference(dev->grab);
86 if (handle)
87 handle->handler->event(handle, type, code, value);
88 else {
89 bool filtered = false;
91 list_for_each_entry_rcu(handle, &dev->h_list, d_node) {
92 if (!handle->open)
93 continue;
95 handler = handle->handler;
96 if (!handler->filter) {
97 if (filtered)
98 break;
100 handler->event(handle, type, code, value);
102 } else if (handler->filter(handle, type, code, value))
103 filtered = true;
107 rcu_read_unlock();
111 * Generate software autorepeat event. Note that we take
112 * dev->event_lock here to avoid racing with input_event
113 * which may cause keys get "stuck".
115 static void input_repeat_key(unsigned long data)
117 struct input_dev *dev = (void *) data;
118 unsigned long flags;
120 spin_lock_irqsave(&dev->event_lock, flags);
122 if (test_bit(dev->repeat_key, dev->key) &&
123 is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
125 input_pass_event(dev, EV_KEY, dev->repeat_key, 2);
127 if (dev->sync) {
129 * Only send SYN_REPORT if we are not in a middle
130 * of driver parsing a new hardware packet.
131 * Otherwise assume that the driver will send
132 * SYN_REPORT once it's done.
134 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
137 if (dev->rep[REP_PERIOD])
138 mod_timer(&dev->timer, jiffies +
139 msecs_to_jiffies(dev->rep[REP_PERIOD]));
142 spin_unlock_irqrestore(&dev->event_lock, flags);
145 static void input_start_autorepeat(struct input_dev *dev, int code)
147 if (test_bit(EV_REP, dev->evbit) &&
148 dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
149 dev->timer.data) {
150 dev->repeat_key = code;
151 mod_timer(&dev->timer,
152 jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
156 static void input_stop_autorepeat(struct input_dev *dev)
158 del_timer(&dev->timer);
161 #define INPUT_IGNORE_EVENT 0
162 #define INPUT_PASS_TO_HANDLERS 1
163 #define INPUT_PASS_TO_DEVICE 2
164 #define INPUT_PASS_TO_ALL (INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
166 static int input_handle_abs_event(struct input_dev *dev,
167 unsigned int code, int *pval)
169 bool is_mt_event;
170 int *pold;
172 if (code == ABS_MT_SLOT) {
174 * "Stage" the event; we'll flush it later, when we
175 * get actual touch data.
177 if (*pval >= 0 && *pval < dev->mtsize)
178 dev->slot = *pval;
180 return INPUT_IGNORE_EVENT;
183 is_mt_event = code >= ABS_MT_FIRST && code <= ABS_MT_LAST;
185 if (!is_mt_event) {
186 pold = &dev->absinfo[code].value;
187 } else if (dev->mt) {
188 struct input_mt_slot *mtslot = &dev->mt[dev->slot];
189 pold = &mtslot->abs[code - ABS_MT_FIRST];
190 } else {
192 * Bypass filtering for multi-touch events when
193 * not employing slots.
195 pold = NULL;
198 if (pold) {
199 *pval = input_defuzz_abs_event(*pval, *pold,
200 dev->absinfo[code].fuzz);
201 if (*pold == *pval)
202 return INPUT_IGNORE_EVENT;
204 *pold = *pval;
207 /* Flush pending "slot" event */
208 if (is_mt_event && dev->slot != input_abs_get_val(dev, ABS_MT_SLOT)) {
209 input_abs_set_val(dev, ABS_MT_SLOT, dev->slot);
210 input_pass_event(dev, EV_ABS, ABS_MT_SLOT, dev->slot);
213 return INPUT_PASS_TO_HANDLERS;
216 static void input_handle_event(struct input_dev *dev,
217 unsigned int type, unsigned int code, int value)
219 int disposition = INPUT_IGNORE_EVENT;
221 switch (type) {
223 case EV_SYN:
224 switch (code) {
225 case SYN_CONFIG:
226 disposition = INPUT_PASS_TO_ALL;
227 break;
229 case SYN_REPORT:
230 if (!dev->sync) {
231 dev->sync = true;
232 disposition = INPUT_PASS_TO_HANDLERS;
234 break;
235 case SYN_MT_REPORT:
236 dev->sync = false;
237 disposition = INPUT_PASS_TO_HANDLERS;
238 break;
240 break;
242 case EV_KEY:
243 if (is_event_supported(code, dev->keybit, KEY_MAX) &&
244 !!test_bit(code, dev->key) != value) {
246 if (value != 2) {
247 __change_bit(code, dev->key);
248 if (value)
249 input_start_autorepeat(dev, code);
250 else
251 input_stop_autorepeat(dev);
254 disposition = INPUT_PASS_TO_HANDLERS;
256 break;
258 case EV_SW:
259 if (is_event_supported(code, dev->swbit, SW_MAX) &&
260 !!test_bit(code, dev->sw) != value) {
262 __change_bit(code, dev->sw);
263 disposition = INPUT_PASS_TO_HANDLERS;
265 break;
267 case EV_ABS:
268 if (is_event_supported(code, dev->absbit, ABS_MAX))
269 disposition = input_handle_abs_event(dev, code, &value);
271 break;
273 case EV_REL:
274 if (is_event_supported(code, dev->relbit, REL_MAX) && value)
275 disposition = INPUT_PASS_TO_HANDLERS;
277 break;
279 case EV_MSC:
280 if (is_event_supported(code, dev->mscbit, MSC_MAX))
281 disposition = INPUT_PASS_TO_ALL;
283 break;
285 case EV_LED:
286 if (is_event_supported(code, dev->ledbit, LED_MAX) &&
287 !!test_bit(code, dev->led) != value) {
289 __change_bit(code, dev->led);
290 disposition = INPUT_PASS_TO_ALL;
292 break;
294 case EV_SND:
295 if (is_event_supported(code, dev->sndbit, SND_MAX)) {
297 if (!!test_bit(code, dev->snd) != !!value)
298 __change_bit(code, dev->snd);
299 disposition = INPUT_PASS_TO_ALL;
301 break;
303 case EV_REP:
304 if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
305 dev->rep[code] = value;
306 disposition = INPUT_PASS_TO_ALL;
308 break;
310 case EV_FF:
311 if (value >= 0)
312 disposition = INPUT_PASS_TO_ALL;
313 break;
315 case EV_PWR:
316 disposition = INPUT_PASS_TO_ALL;
317 break;
320 if (disposition != INPUT_IGNORE_EVENT && type != EV_SYN)
321 dev->sync = false;
323 if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
324 dev->event(dev, type, code, value);
326 if (disposition & INPUT_PASS_TO_HANDLERS)
327 input_pass_event(dev, type, code, value);
331 * input_event() - report new input event
332 * @dev: device that generated the event
333 * @type: type of the event
334 * @code: event code
335 * @value: value of the event
337 * This function should be used by drivers implementing various input
338 * devices to report input events. See also input_inject_event().
340 * NOTE: input_event() may be safely used right after input device was
341 * allocated with input_allocate_device(), even before it is registered
342 * with input_register_device(), but the event will not reach any of the
343 * input handlers. Such early invocation of input_event() may be used
344 * to 'seed' initial state of a switch or initial position of absolute
345 * axis, etc.
347 void input_event(struct input_dev *dev,
348 unsigned int type, unsigned int code, int value)
350 unsigned long flags;
352 if (is_event_supported(type, dev->evbit, EV_MAX)) {
354 spin_lock_irqsave(&dev->event_lock, flags);
355 add_input_randomness(type, code, value);
356 input_handle_event(dev, type, code, value);
357 spin_unlock_irqrestore(&dev->event_lock, flags);
360 EXPORT_SYMBOL(input_event);
363 * input_inject_event() - send input event from input handler
364 * @handle: input handle to send event through
365 * @type: type of the event
366 * @code: event code
367 * @value: value of the event
369 * Similar to input_event() but will ignore event if device is
370 * "grabbed" and handle injecting event is not the one that owns
371 * the device.
373 void input_inject_event(struct input_handle *handle,
374 unsigned int type, unsigned int code, int value)
376 struct input_dev *dev = handle->dev;
377 struct input_handle *grab;
378 unsigned long flags;
380 if (is_event_supported(type, dev->evbit, EV_MAX)) {
381 spin_lock_irqsave(&dev->event_lock, flags);
383 rcu_read_lock();
384 grab = rcu_dereference(dev->grab);
385 if (!grab || grab == handle)
386 input_handle_event(dev, type, code, value);
387 rcu_read_unlock();
389 spin_unlock_irqrestore(&dev->event_lock, flags);
392 EXPORT_SYMBOL(input_inject_event);
395 * input_alloc_absinfo - allocates array of input_absinfo structs
396 * @dev: the input device emitting absolute events
398 * If the absinfo struct the caller asked for is already allocated, this
399 * functions will not do anything.
401 void input_alloc_absinfo(struct input_dev *dev)
403 if (!dev->absinfo)
404 dev->absinfo = kcalloc(ABS_CNT, sizeof(struct input_absinfo),
405 GFP_KERNEL);
407 WARN(!dev->absinfo, "%s(): kcalloc() failed?\n", __func__);
409 EXPORT_SYMBOL(input_alloc_absinfo);
411 void input_set_abs_params(struct input_dev *dev, unsigned int axis,
412 int min, int max, int fuzz, int flat)
414 struct input_absinfo *absinfo;
416 input_alloc_absinfo(dev);
417 if (!dev->absinfo)
418 return;
420 absinfo = &dev->absinfo[axis];
421 absinfo->minimum = min;
422 absinfo->maximum = max;
423 absinfo->fuzz = fuzz;
424 absinfo->flat = flat;
426 dev->absbit[BIT_WORD(axis)] |= BIT_MASK(axis);
428 EXPORT_SYMBOL(input_set_abs_params);
432 * input_grab_device - grabs device for exclusive use
433 * @handle: input handle that wants to own the device
435 * When a device is grabbed by an input handle all events generated by
436 * the device are delivered only to this handle. Also events injected
437 * by other input handles are ignored while device is grabbed.
439 int input_grab_device(struct input_handle *handle)
441 struct input_dev *dev = handle->dev;
442 int retval;
444 retval = mutex_lock_interruptible(&dev->mutex);
445 if (retval)
446 return retval;
448 if (dev->grab) {
449 retval = -EBUSY;
450 goto out;
453 rcu_assign_pointer(dev->grab, handle);
454 synchronize_rcu();
456 out:
457 mutex_unlock(&dev->mutex);
458 return retval;
460 EXPORT_SYMBOL(input_grab_device);
462 static void __input_release_device(struct input_handle *handle)
464 struct input_dev *dev = handle->dev;
466 if (dev->grab == handle) {
467 rcu_assign_pointer(dev->grab, NULL);
468 /* Make sure input_pass_event() notices that grab is gone */
469 synchronize_rcu();
471 list_for_each_entry(handle, &dev->h_list, d_node)
472 if (handle->open && handle->handler->start)
473 handle->handler->start(handle);
478 * input_release_device - release previously grabbed device
479 * @handle: input handle that owns the device
481 * Releases previously grabbed device so that other input handles can
482 * start receiving input events. Upon release all handlers attached
483 * to the device have their start() method called so they have a change
484 * to synchronize device state with the rest of the system.
486 void input_release_device(struct input_handle *handle)
488 struct input_dev *dev = handle->dev;
490 mutex_lock(&dev->mutex);
491 __input_release_device(handle);
492 mutex_unlock(&dev->mutex);
494 EXPORT_SYMBOL(input_release_device);
497 * input_open_device - open input device
498 * @handle: handle through which device is being accessed
500 * This function should be called by input handlers when they
501 * want to start receive events from given input device.
503 int input_open_device(struct input_handle *handle)
505 struct input_dev *dev = handle->dev;
506 int retval;
508 retval = mutex_lock_interruptible(&dev->mutex);
509 if (retval)
510 return retval;
512 if (dev->going_away) {
513 retval = -ENODEV;
514 goto out;
517 handle->open++;
519 if (!dev->users++ && dev->open)
520 retval = dev->open(dev);
522 if (retval) {
523 dev->users--;
524 if (!--handle->open) {
526 * Make sure we are not delivering any more events
527 * through this handle
529 synchronize_rcu();
533 out:
534 mutex_unlock(&dev->mutex);
535 return retval;
537 EXPORT_SYMBOL(input_open_device);
539 int input_flush_device(struct input_handle *handle, struct file *file)
541 struct input_dev *dev = handle->dev;
542 int retval;
544 retval = mutex_lock_interruptible(&dev->mutex);
545 if (retval)
546 return retval;
548 if (dev->flush)
549 retval = dev->flush(dev, file);
551 mutex_unlock(&dev->mutex);
552 return retval;
554 EXPORT_SYMBOL(input_flush_device);
557 * input_close_device - close input device
558 * @handle: handle through which device is being accessed
560 * This function should be called by input handlers when they
561 * want to stop receive events from given input device.
563 void input_close_device(struct input_handle *handle)
565 struct input_dev *dev = handle->dev;
567 mutex_lock(&dev->mutex);
569 __input_release_device(handle);
571 if (!--dev->users && dev->close)
572 dev->close(dev);
574 if (!--handle->open) {
576 * synchronize_rcu() makes sure that input_pass_event()
577 * completed and that no more input events are delivered
578 * through this handle
580 synchronize_rcu();
583 mutex_unlock(&dev->mutex);
585 EXPORT_SYMBOL(input_close_device);
588 * Simulate keyup events for all keys that are marked as pressed.
589 * The function must be called with dev->event_lock held.
591 static void input_dev_release_keys(struct input_dev *dev)
593 int code;
595 if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
596 for (code = 0; code <= KEY_MAX; code++) {
597 if (is_event_supported(code, dev->keybit, KEY_MAX) &&
598 __test_and_clear_bit(code, dev->key)) {
599 input_pass_event(dev, EV_KEY, code, 0);
602 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
607 * Prepare device for unregistering
609 static void input_disconnect_device(struct input_dev *dev)
611 struct input_handle *handle;
614 * Mark device as going away. Note that we take dev->mutex here
615 * not to protect access to dev->going_away but rather to ensure
616 * that there are no threads in the middle of input_open_device()
618 mutex_lock(&dev->mutex);
619 dev->going_away = true;
620 mutex_unlock(&dev->mutex);
622 spin_lock_irq(&dev->event_lock);
625 * Simulate keyup events for all pressed keys so that handlers
626 * are not left with "stuck" keys. The driver may continue
627 * generate events even after we done here but they will not
628 * reach any handlers.
630 input_dev_release_keys(dev);
632 list_for_each_entry(handle, &dev->h_list, d_node)
633 handle->open = 0;
635 spin_unlock_irq(&dev->event_lock);
639 * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
640 * @ke: keymap entry containing scancode to be converted.
641 * @scancode: pointer to the location where converted scancode should
642 * be stored.
644 * This function is used to convert scancode stored in &struct keymap_entry
645 * into scalar form understood by legacy keymap handling methods. These
646 * methods expect scancodes to be represented as 'unsigned int'.
648 int input_scancode_to_scalar(const struct input_keymap_entry *ke,
649 unsigned int *scancode)
651 switch (ke->len) {
652 case 1:
653 *scancode = *((u8 *)ke->scancode);
654 break;
656 case 2:
657 *scancode = *((u16 *)ke->scancode);
658 break;
660 case 4:
661 *scancode = *((u32 *)ke->scancode);
662 break;
664 default:
665 return -EINVAL;
668 return 0;
670 EXPORT_SYMBOL(input_scancode_to_scalar);
673 * Those routines handle the default case where no [gs]etkeycode() is
674 * defined. In this case, an array indexed by the scancode is used.
677 static unsigned int input_fetch_keycode(struct input_dev *dev,
678 unsigned int index)
680 switch (dev->keycodesize) {
681 case 1:
682 return ((u8 *)dev->keycode)[index];
684 case 2:
685 return ((u16 *)dev->keycode)[index];
687 default:
688 return ((u32 *)dev->keycode)[index];
692 static int input_default_getkeycode(struct input_dev *dev,
693 struct input_keymap_entry *ke)
695 unsigned int index;
696 int error;
698 if (!dev->keycodesize)
699 return -EINVAL;
701 if (ke->flags & INPUT_KEYMAP_BY_INDEX)
702 index = ke->index;
703 else {
704 error = input_scancode_to_scalar(ke, &index);
705 if (error)
706 return error;
709 if (index >= dev->keycodemax)
710 return -EINVAL;
712 ke->keycode = input_fetch_keycode(dev, index);
713 ke->index = index;
714 ke->len = sizeof(index);
715 memcpy(ke->scancode, &index, sizeof(index));
717 return 0;
720 static int input_default_setkeycode(struct input_dev *dev,
721 const struct input_keymap_entry *ke,
722 unsigned int *old_keycode)
724 unsigned int index;
725 int error;
726 int i;
728 if (!dev->keycodesize)
729 return -EINVAL;
731 if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
732 index = ke->index;
733 } else {
734 error = input_scancode_to_scalar(ke, &index);
735 if (error)
736 return error;
739 if (index >= dev->keycodemax)
740 return -EINVAL;
742 if (dev->keycodesize < sizeof(ke->keycode) &&
743 (ke->keycode >> (dev->keycodesize * 8)))
744 return -EINVAL;
746 switch (dev->keycodesize) {
747 case 1: {
748 u8 *k = (u8 *)dev->keycode;
749 *old_keycode = k[index];
750 k[index] = ke->keycode;
751 break;
753 case 2: {
754 u16 *k = (u16 *)dev->keycode;
755 *old_keycode = k[index];
756 k[index] = ke->keycode;
757 break;
759 default: {
760 u32 *k = (u32 *)dev->keycode;
761 *old_keycode = k[index];
762 k[index] = ke->keycode;
763 break;
767 __clear_bit(*old_keycode, dev->keybit);
768 __set_bit(ke->keycode, dev->keybit);
770 for (i = 0; i < dev->keycodemax; i++) {
771 if (input_fetch_keycode(dev, i) == *old_keycode) {
772 __set_bit(*old_keycode, dev->keybit);
773 break; /* Setting the bit twice is useless, so break */
777 return 0;
781 * input_get_keycode - retrieve keycode currently mapped to a given scancode
782 * @dev: input device which keymap is being queried
783 * @ke: keymap entry
785 * This function should be called by anyone interested in retrieving current
786 * keymap. Presently evdev handlers use it.
788 int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
790 unsigned long flags;
791 int retval;
793 spin_lock_irqsave(&dev->event_lock, flags);
795 if (dev->getkeycode) {
797 * Support for legacy drivers, that don't implement the new
798 * ioctls
800 u32 scancode = ke->index;
802 memcpy(ke->scancode, &scancode, sizeof(scancode));
803 ke->len = sizeof(scancode);
804 retval = dev->getkeycode(dev, scancode, &ke->keycode);
805 } else {
806 retval = dev->getkeycode_new(dev, ke);
809 spin_unlock_irqrestore(&dev->event_lock, flags);
810 return retval;
812 EXPORT_SYMBOL(input_get_keycode);
815 * input_set_keycode - attribute a keycode to a given scancode
816 * @dev: input device which keymap is being updated
817 * @ke: new keymap entry
819 * This function should be called by anyone needing to update current
820 * keymap. Presently keyboard and evdev handlers use it.
822 int input_set_keycode(struct input_dev *dev,
823 const struct input_keymap_entry *ke)
825 unsigned long flags;
826 unsigned int old_keycode;
827 int retval;
829 if (ke->keycode > KEY_MAX)
830 return -EINVAL;
832 spin_lock_irqsave(&dev->event_lock, flags);
834 if (dev->setkeycode) {
836 * Support for legacy drivers, that don't implement the new
837 * ioctls
839 unsigned int scancode;
841 retval = input_scancode_to_scalar(ke, &scancode);
842 if (retval)
843 goto out;
846 * We need to know the old scancode, in order to generate a
847 * keyup effect, if the set operation happens successfully
849 if (!dev->getkeycode) {
850 retval = -EINVAL;
851 goto out;
854 retval = dev->getkeycode(dev, scancode, &old_keycode);
855 if (retval)
856 goto out;
858 retval = dev->setkeycode(dev, scancode, ke->keycode);
859 } else {
860 retval = dev->setkeycode_new(dev, ke, &old_keycode);
863 if (retval)
864 goto out;
866 /* Make sure KEY_RESERVED did not get enabled. */
867 __clear_bit(KEY_RESERVED, dev->keybit);
870 * Simulate keyup event if keycode is not present
871 * in the keymap anymore
873 if (test_bit(EV_KEY, dev->evbit) &&
874 !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
875 __test_and_clear_bit(old_keycode, dev->key)) {
877 input_pass_event(dev, EV_KEY, old_keycode, 0);
878 if (dev->sync)
879 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
882 out:
883 spin_unlock_irqrestore(&dev->event_lock, flags);
885 return retval;
887 EXPORT_SYMBOL(input_set_keycode);
889 #define MATCH_BIT(bit, max) \
890 for (i = 0; i < BITS_TO_LONGS(max); i++) \
891 if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \
892 break; \
893 if (i != BITS_TO_LONGS(max)) \
894 continue;
896 static const struct input_device_id *input_match_device(struct input_handler *handler,
897 struct input_dev *dev)
899 const struct input_device_id *id;
900 int i;
902 for (id = handler->id_table; id->flags || id->driver_info; id++) {
904 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
905 if (id->bustype != dev->id.bustype)
906 continue;
908 if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
909 if (id->vendor != dev->id.vendor)
910 continue;
912 if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
913 if (id->product != dev->id.product)
914 continue;
916 if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
917 if (id->version != dev->id.version)
918 continue;
920 MATCH_BIT(evbit, EV_MAX);
921 MATCH_BIT(keybit, KEY_MAX);
922 MATCH_BIT(relbit, REL_MAX);
923 MATCH_BIT(absbit, ABS_MAX);
924 MATCH_BIT(mscbit, MSC_MAX);
925 MATCH_BIT(ledbit, LED_MAX);
926 MATCH_BIT(sndbit, SND_MAX);
927 MATCH_BIT(ffbit, FF_MAX);
928 MATCH_BIT(swbit, SW_MAX);
930 if (!handler->match || handler->match(handler, dev))
931 return id;
934 return NULL;
937 static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
939 const struct input_device_id *id;
940 int error;
942 id = input_match_device(handler, dev);
943 if (!id)
944 return -ENODEV;
946 error = handler->connect(handler, dev, id);
947 if (error && error != -ENODEV)
948 pr_err("failed to attach handler %s to device %s, error: %d\n",
949 handler->name, kobject_name(&dev->dev.kobj), error);
951 return error;
954 #ifdef CONFIG_COMPAT
956 static int input_bits_to_string(char *buf, int buf_size,
957 unsigned long bits, bool skip_empty)
959 int len = 0;
961 if (INPUT_COMPAT_TEST) {
962 u32 dword = bits >> 32;
963 if (dword || !skip_empty)
964 len += snprintf(buf, buf_size, "%x ", dword);
966 dword = bits & 0xffffffffUL;
967 if (dword || !skip_empty || len)
968 len += snprintf(buf + len, max(buf_size - len, 0),
969 "%x", dword);
970 } else {
971 if (bits || !skip_empty)
972 len += snprintf(buf, buf_size, "%lx", bits);
975 return len;
978 #else /* !CONFIG_COMPAT */
980 static int input_bits_to_string(char *buf, int buf_size,
981 unsigned long bits, bool skip_empty)
983 return bits || !skip_empty ?
984 snprintf(buf, buf_size, "%lx", bits) : 0;
987 #endif
989 #ifdef CONFIG_PROC_FS
991 static struct proc_dir_entry *proc_bus_input_dir;
992 static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
993 static int input_devices_state;
995 static inline void input_wakeup_procfs_readers(void)
997 input_devices_state++;
998 wake_up(&input_devices_poll_wait);
1001 static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
1003 poll_wait(file, &input_devices_poll_wait, wait);
1004 if (file->f_version != input_devices_state) {
1005 file->f_version = input_devices_state;
1006 return POLLIN | POLLRDNORM;
1009 return 0;
1012 union input_seq_state {
1013 struct {
1014 unsigned short pos;
1015 bool mutex_acquired;
1017 void *p;
1020 static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
1022 union input_seq_state *state = (union input_seq_state *)&seq->private;
1023 int error;
1025 /* We need to fit into seq->private pointer */
1026 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1028 error = mutex_lock_interruptible(&input_mutex);
1029 if (error) {
1030 state->mutex_acquired = false;
1031 return ERR_PTR(error);
1034 state->mutex_acquired = true;
1036 return seq_list_start(&input_dev_list, *pos);
1039 static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1041 return seq_list_next(v, &input_dev_list, pos);
1044 static void input_seq_stop(struct seq_file *seq, void *v)
1046 union input_seq_state *state = (union input_seq_state *)&seq->private;
1048 if (state->mutex_acquired)
1049 mutex_unlock(&input_mutex);
1052 static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
1053 unsigned long *bitmap, int max)
1055 int i;
1056 bool skip_empty = true;
1057 char buf[18];
1059 seq_printf(seq, "B: %s=", name);
1061 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1062 if (input_bits_to_string(buf, sizeof(buf),
1063 bitmap[i], skip_empty)) {
1064 skip_empty = false;
1065 seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
1070 * If no output was produced print a single 0.
1072 if (skip_empty)
1073 seq_puts(seq, "0");
1075 seq_putc(seq, '\n');
1078 static int input_devices_seq_show(struct seq_file *seq, void *v)
1080 struct input_dev *dev = container_of(v, struct input_dev, node);
1081 const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1082 struct input_handle *handle;
1084 seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
1085 dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
1087 seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
1088 seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
1089 seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
1090 seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1091 seq_printf(seq, "H: Handlers=");
1093 list_for_each_entry(handle, &dev->h_list, d_node)
1094 seq_printf(seq, "%s ", handle->name);
1095 seq_putc(seq, '\n');
1097 input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
1099 input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
1100 if (test_bit(EV_KEY, dev->evbit))
1101 input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
1102 if (test_bit(EV_REL, dev->evbit))
1103 input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
1104 if (test_bit(EV_ABS, dev->evbit))
1105 input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
1106 if (test_bit(EV_MSC, dev->evbit))
1107 input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
1108 if (test_bit(EV_LED, dev->evbit))
1109 input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
1110 if (test_bit(EV_SND, dev->evbit))
1111 input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
1112 if (test_bit(EV_FF, dev->evbit))
1113 input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
1114 if (test_bit(EV_SW, dev->evbit))
1115 input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
1117 seq_putc(seq, '\n');
1119 kfree(path);
1120 return 0;
1123 static const struct seq_operations input_devices_seq_ops = {
1124 .start = input_devices_seq_start,
1125 .next = input_devices_seq_next,
1126 .stop = input_seq_stop,
1127 .show = input_devices_seq_show,
1130 static int input_proc_devices_open(struct inode *inode, struct file *file)
1132 return seq_open(file, &input_devices_seq_ops);
1135 static const struct file_operations input_devices_fileops = {
1136 .owner = THIS_MODULE,
1137 .open = input_proc_devices_open,
1138 .poll = input_proc_devices_poll,
1139 .read = seq_read,
1140 .llseek = seq_lseek,
1141 .release = seq_release,
1144 static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
1146 union input_seq_state *state = (union input_seq_state *)&seq->private;
1147 int error;
1149 /* We need to fit into seq->private pointer */
1150 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1152 error = mutex_lock_interruptible(&input_mutex);
1153 if (error) {
1154 state->mutex_acquired = false;
1155 return ERR_PTR(error);
1158 state->mutex_acquired = true;
1159 state->pos = *pos;
1161 return seq_list_start(&input_handler_list, *pos);
1164 static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1166 union input_seq_state *state = (union input_seq_state *)&seq->private;
1168 state->pos = *pos + 1;
1169 return seq_list_next(v, &input_handler_list, pos);
1172 static int input_handlers_seq_show(struct seq_file *seq, void *v)
1174 struct input_handler *handler = container_of(v, struct input_handler, node);
1175 union input_seq_state *state = (union input_seq_state *)&seq->private;
1177 seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
1178 if (handler->filter)
1179 seq_puts(seq, " (filter)");
1180 if (handler->fops)
1181 seq_printf(seq, " Minor=%d", handler->minor);
1182 seq_putc(seq, '\n');
1184 return 0;
1187 static const struct seq_operations input_handlers_seq_ops = {
1188 .start = input_handlers_seq_start,
1189 .next = input_handlers_seq_next,
1190 .stop = input_seq_stop,
1191 .show = input_handlers_seq_show,
1194 static int input_proc_handlers_open(struct inode *inode, struct file *file)
1196 return seq_open(file, &input_handlers_seq_ops);
1199 static const struct file_operations input_handlers_fileops = {
1200 .owner = THIS_MODULE,
1201 .open = input_proc_handlers_open,
1202 .read = seq_read,
1203 .llseek = seq_lseek,
1204 .release = seq_release,
1207 static int __init input_proc_init(void)
1209 struct proc_dir_entry *entry;
1211 proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1212 if (!proc_bus_input_dir)
1213 return -ENOMEM;
1215 entry = proc_create("devices", 0, proc_bus_input_dir,
1216 &input_devices_fileops);
1217 if (!entry)
1218 goto fail1;
1220 entry = proc_create("handlers", 0, proc_bus_input_dir,
1221 &input_handlers_fileops);
1222 if (!entry)
1223 goto fail2;
1225 return 0;
1227 fail2: remove_proc_entry("devices", proc_bus_input_dir);
1228 fail1: remove_proc_entry("bus/input", NULL);
1229 return -ENOMEM;
1232 static void input_proc_exit(void)
1234 remove_proc_entry("devices", proc_bus_input_dir);
1235 remove_proc_entry("handlers", proc_bus_input_dir);
1236 remove_proc_entry("bus/input", NULL);
1239 #else /* !CONFIG_PROC_FS */
1240 static inline void input_wakeup_procfs_readers(void) { }
1241 static inline int input_proc_init(void) { return 0; }
1242 static inline void input_proc_exit(void) { }
1243 #endif
1245 #define INPUT_DEV_STRING_ATTR_SHOW(name) \
1246 static ssize_t input_dev_show_##name(struct device *dev, \
1247 struct device_attribute *attr, \
1248 char *buf) \
1250 struct input_dev *input_dev = to_input_dev(dev); \
1252 return scnprintf(buf, PAGE_SIZE, "%s\n", \
1253 input_dev->name ? input_dev->name : ""); \
1255 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1257 INPUT_DEV_STRING_ATTR_SHOW(name);
1258 INPUT_DEV_STRING_ATTR_SHOW(phys);
1259 INPUT_DEV_STRING_ATTR_SHOW(uniq);
1261 static int input_print_modalias_bits(char *buf, int size,
1262 char name, unsigned long *bm,
1263 unsigned int min_bit, unsigned int max_bit)
1265 int len = 0, i;
1267 len += snprintf(buf, max(size, 0), "%c", name);
1268 for (i = min_bit; i < max_bit; i++)
1269 if (bm[BIT_WORD(i)] & BIT_MASK(i))
1270 len += snprintf(buf + len, max(size - len, 0), "%X,", i);
1271 return len;
1274 static int input_print_modalias(char *buf, int size, struct input_dev *id,
1275 int add_cr)
1277 int len;
1279 len = snprintf(buf, max(size, 0),
1280 "input:b%04Xv%04Xp%04Xe%04X-",
1281 id->id.bustype, id->id.vendor,
1282 id->id.product, id->id.version);
1284 len += input_print_modalias_bits(buf + len, size - len,
1285 'e', id->evbit, 0, EV_MAX);
1286 len += input_print_modalias_bits(buf + len, size - len,
1287 'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1288 len += input_print_modalias_bits(buf + len, size - len,
1289 'r', id->relbit, 0, REL_MAX);
1290 len += input_print_modalias_bits(buf + len, size - len,
1291 'a', id->absbit, 0, ABS_MAX);
1292 len += input_print_modalias_bits(buf + len, size - len,
1293 'm', id->mscbit, 0, MSC_MAX);
1294 len += input_print_modalias_bits(buf + len, size - len,
1295 'l', id->ledbit, 0, LED_MAX);
1296 len += input_print_modalias_bits(buf + len, size - len,
1297 's', id->sndbit, 0, SND_MAX);
1298 len += input_print_modalias_bits(buf + len, size - len,
1299 'f', id->ffbit, 0, FF_MAX);
1300 len += input_print_modalias_bits(buf + len, size - len,
1301 'w', id->swbit, 0, SW_MAX);
1303 if (add_cr)
1304 len += snprintf(buf + len, max(size - len, 0), "\n");
1306 return len;
1309 static ssize_t input_dev_show_modalias(struct device *dev,
1310 struct device_attribute *attr,
1311 char *buf)
1313 struct input_dev *id = to_input_dev(dev);
1314 ssize_t len;
1316 len = input_print_modalias(buf, PAGE_SIZE, id, 1);
1318 return min_t(int, len, PAGE_SIZE);
1320 static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1322 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1323 int max, int add_cr);
1325 static ssize_t input_dev_show_properties(struct device *dev,
1326 struct device_attribute *attr,
1327 char *buf)
1329 struct input_dev *input_dev = to_input_dev(dev);
1330 int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
1331 INPUT_PROP_MAX, true);
1332 return min_t(int, len, PAGE_SIZE);
1334 static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
1336 static struct attribute *input_dev_attrs[] = {
1337 &dev_attr_name.attr,
1338 &dev_attr_phys.attr,
1339 &dev_attr_uniq.attr,
1340 &dev_attr_modalias.attr,
1341 &dev_attr_properties.attr,
1342 NULL
1345 static struct attribute_group input_dev_attr_group = {
1346 .attrs = input_dev_attrs,
1349 #define INPUT_DEV_ID_ATTR(name) \
1350 static ssize_t input_dev_show_id_##name(struct device *dev, \
1351 struct device_attribute *attr, \
1352 char *buf) \
1354 struct input_dev *input_dev = to_input_dev(dev); \
1355 return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name); \
1357 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1359 INPUT_DEV_ID_ATTR(bustype);
1360 INPUT_DEV_ID_ATTR(vendor);
1361 INPUT_DEV_ID_ATTR(product);
1362 INPUT_DEV_ID_ATTR(version);
1364 static struct attribute *input_dev_id_attrs[] = {
1365 &dev_attr_bustype.attr,
1366 &dev_attr_vendor.attr,
1367 &dev_attr_product.attr,
1368 &dev_attr_version.attr,
1369 NULL
1372 static struct attribute_group input_dev_id_attr_group = {
1373 .name = "id",
1374 .attrs = input_dev_id_attrs,
1377 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1378 int max, int add_cr)
1380 int i;
1381 int len = 0;
1382 bool skip_empty = true;
1384 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1385 len += input_bits_to_string(buf + len, max(buf_size - len, 0),
1386 bitmap[i], skip_empty);
1387 if (len) {
1388 skip_empty = false;
1389 if (i > 0)
1390 len += snprintf(buf + len, max(buf_size - len, 0), " ");
1395 * If no output was produced print a single 0.
1397 if (len == 0)
1398 len = snprintf(buf, buf_size, "%d", 0);
1400 if (add_cr)
1401 len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1403 return len;
1406 #define INPUT_DEV_CAP_ATTR(ev, bm) \
1407 static ssize_t input_dev_show_cap_##bm(struct device *dev, \
1408 struct device_attribute *attr, \
1409 char *buf) \
1411 struct input_dev *input_dev = to_input_dev(dev); \
1412 int len = input_print_bitmap(buf, PAGE_SIZE, \
1413 input_dev->bm##bit, ev##_MAX, \
1414 true); \
1415 return min_t(int, len, PAGE_SIZE); \
1417 static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1419 INPUT_DEV_CAP_ATTR(EV, ev);
1420 INPUT_DEV_CAP_ATTR(KEY, key);
1421 INPUT_DEV_CAP_ATTR(REL, rel);
1422 INPUT_DEV_CAP_ATTR(ABS, abs);
1423 INPUT_DEV_CAP_ATTR(MSC, msc);
1424 INPUT_DEV_CAP_ATTR(LED, led);
1425 INPUT_DEV_CAP_ATTR(SND, snd);
1426 INPUT_DEV_CAP_ATTR(FF, ff);
1427 INPUT_DEV_CAP_ATTR(SW, sw);
1429 static struct attribute *input_dev_caps_attrs[] = {
1430 &dev_attr_ev.attr,
1431 &dev_attr_key.attr,
1432 &dev_attr_rel.attr,
1433 &dev_attr_abs.attr,
1434 &dev_attr_msc.attr,
1435 &dev_attr_led.attr,
1436 &dev_attr_snd.attr,
1437 &dev_attr_ff.attr,
1438 &dev_attr_sw.attr,
1439 NULL
1442 static struct attribute_group input_dev_caps_attr_group = {
1443 .name = "capabilities",
1444 .attrs = input_dev_caps_attrs,
1447 static const struct attribute_group *input_dev_attr_groups[] = {
1448 &input_dev_attr_group,
1449 &input_dev_id_attr_group,
1450 &input_dev_caps_attr_group,
1451 NULL
1454 static void input_dev_release(struct device *device)
1456 struct input_dev *dev = to_input_dev(device);
1458 input_ff_destroy(dev);
1459 input_mt_destroy_slots(dev);
1460 kfree(dev->absinfo);
1461 kfree(dev);
1463 module_put(THIS_MODULE);
1467 * Input uevent interface - loading event handlers based on
1468 * device bitfields.
1470 static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1471 const char *name, unsigned long *bitmap, int max)
1473 int len;
1475 if (add_uevent_var(env, "%s", name))
1476 return -ENOMEM;
1478 len = input_print_bitmap(&env->buf[env->buflen - 1],
1479 sizeof(env->buf) - env->buflen,
1480 bitmap, max, false);
1481 if (len >= (sizeof(env->buf) - env->buflen))
1482 return -ENOMEM;
1484 env->buflen += len;
1485 return 0;
1488 static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1489 struct input_dev *dev)
1491 int len;
1493 if (add_uevent_var(env, "MODALIAS="))
1494 return -ENOMEM;
1496 len = input_print_modalias(&env->buf[env->buflen - 1],
1497 sizeof(env->buf) - env->buflen,
1498 dev, 0);
1499 if (len >= (sizeof(env->buf) - env->buflen))
1500 return -ENOMEM;
1502 env->buflen += len;
1503 return 0;
1506 #define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \
1507 do { \
1508 int err = add_uevent_var(env, fmt, val); \
1509 if (err) \
1510 return err; \
1511 } while (0)
1513 #define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max) \
1514 do { \
1515 int err = input_add_uevent_bm_var(env, name, bm, max); \
1516 if (err) \
1517 return err; \
1518 } while (0)
1520 #define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \
1521 do { \
1522 int err = input_add_uevent_modalias_var(env, dev); \
1523 if (err) \
1524 return err; \
1525 } while (0)
1527 static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
1529 struct input_dev *dev = to_input_dev(device);
1531 INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1532 dev->id.bustype, dev->id.vendor,
1533 dev->id.product, dev->id.version);
1534 if (dev->name)
1535 INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1536 if (dev->phys)
1537 INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1538 if (dev->uniq)
1539 INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1541 INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
1543 INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1544 if (test_bit(EV_KEY, dev->evbit))
1545 INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1546 if (test_bit(EV_REL, dev->evbit))
1547 INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1548 if (test_bit(EV_ABS, dev->evbit))
1549 INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1550 if (test_bit(EV_MSC, dev->evbit))
1551 INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1552 if (test_bit(EV_LED, dev->evbit))
1553 INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1554 if (test_bit(EV_SND, dev->evbit))
1555 INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1556 if (test_bit(EV_FF, dev->evbit))
1557 INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1558 if (test_bit(EV_SW, dev->evbit))
1559 INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1561 INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1563 return 0;
1566 #define INPUT_DO_TOGGLE(dev, type, bits, on) \
1567 do { \
1568 int i; \
1569 bool active; \
1571 if (!test_bit(EV_##type, dev->evbit)) \
1572 break; \
1574 for (i = 0; i < type##_MAX; i++) { \
1575 if (!test_bit(i, dev->bits##bit)) \
1576 continue; \
1578 active = test_bit(i, dev->bits); \
1579 if (!active && !on) \
1580 continue; \
1582 dev->event(dev, EV_##type, i, on ? active : 0); \
1584 } while (0)
1586 static void input_dev_toggle(struct input_dev *dev, bool activate)
1588 if (!dev->event)
1589 return;
1591 INPUT_DO_TOGGLE(dev, LED, led, activate);
1592 INPUT_DO_TOGGLE(dev, SND, snd, activate);
1594 if (activate && test_bit(EV_REP, dev->evbit)) {
1595 dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1596 dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1601 * input_reset_device() - reset/restore the state of input device
1602 * @dev: input device whose state needs to be reset
1604 * This function tries to reset the state of an opened input device and
1605 * bring internal state and state if the hardware in sync with each other.
1606 * We mark all keys as released, restore LED state, repeat rate, etc.
1608 void input_reset_device(struct input_dev *dev)
1610 mutex_lock(&dev->mutex);
1612 if (dev->users) {
1613 input_dev_toggle(dev, true);
1616 * Keys that have been pressed at suspend time are unlikely
1617 * to be still pressed when we resume.
1619 spin_lock_irq(&dev->event_lock);
1620 input_dev_release_keys(dev);
1621 spin_unlock_irq(&dev->event_lock);
1624 mutex_unlock(&dev->mutex);
1626 EXPORT_SYMBOL(input_reset_device);
1628 #ifdef CONFIG_PM
1629 static int input_dev_suspend(struct device *dev)
1631 struct input_dev *input_dev = to_input_dev(dev);
1633 mutex_lock(&input_dev->mutex);
1635 if (input_dev->users)
1636 input_dev_toggle(input_dev, false);
1638 mutex_unlock(&input_dev->mutex);
1640 return 0;
1643 static int input_dev_resume(struct device *dev)
1645 struct input_dev *input_dev = to_input_dev(dev);
1647 input_reset_device(input_dev);
1649 return 0;
1652 static const struct dev_pm_ops input_dev_pm_ops = {
1653 .suspend = input_dev_suspend,
1654 .resume = input_dev_resume,
1655 .poweroff = input_dev_suspend,
1656 .restore = input_dev_resume,
1658 #endif /* CONFIG_PM */
1660 static struct device_type input_dev_type = {
1661 .groups = input_dev_attr_groups,
1662 .release = input_dev_release,
1663 .uevent = input_dev_uevent,
1664 #ifdef CONFIG_PM
1665 .pm = &input_dev_pm_ops,
1666 #endif
1669 static char *input_devnode(struct device *dev, mode_t *mode)
1671 return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
1674 struct class input_class = {
1675 .name = "input",
1676 .devnode = input_devnode,
1678 EXPORT_SYMBOL_GPL(input_class);
1681 * input_allocate_device - allocate memory for new input device
1683 * Returns prepared struct input_dev or NULL.
1685 * NOTE: Use input_free_device() to free devices that have not been
1686 * registered; input_unregister_device() should be used for already
1687 * registered devices.
1689 struct input_dev *input_allocate_device(void)
1691 struct input_dev *dev;
1693 dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
1694 if (dev) {
1695 dev->dev.type = &input_dev_type;
1696 dev->dev.class = &input_class;
1697 device_initialize(&dev->dev);
1698 mutex_init(&dev->mutex);
1699 spin_lock_init(&dev->event_lock);
1700 INIT_LIST_HEAD(&dev->h_list);
1701 INIT_LIST_HEAD(&dev->node);
1703 __module_get(THIS_MODULE);
1706 return dev;
1708 EXPORT_SYMBOL(input_allocate_device);
1711 * input_free_device - free memory occupied by input_dev structure
1712 * @dev: input device to free
1714 * This function should only be used if input_register_device()
1715 * was not called yet or if it failed. Once device was registered
1716 * use input_unregister_device() and memory will be freed once last
1717 * reference to the device is dropped.
1719 * Device should be allocated by input_allocate_device().
1721 * NOTE: If there are references to the input device then memory
1722 * will not be freed until last reference is dropped.
1724 void input_free_device(struct input_dev *dev)
1726 if (dev)
1727 input_put_device(dev);
1729 EXPORT_SYMBOL(input_free_device);
1732 * input_set_capability - mark device as capable of a certain event
1733 * @dev: device that is capable of emitting or accepting event
1734 * @type: type of the event (EV_KEY, EV_REL, etc...)
1735 * @code: event code
1737 * In addition to setting up corresponding bit in appropriate capability
1738 * bitmap the function also adjusts dev->evbit.
1740 void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
1742 switch (type) {
1743 case EV_KEY:
1744 __set_bit(code, dev->keybit);
1745 break;
1747 case EV_REL:
1748 __set_bit(code, dev->relbit);
1749 break;
1751 case EV_ABS:
1752 __set_bit(code, dev->absbit);
1753 break;
1755 case EV_MSC:
1756 __set_bit(code, dev->mscbit);
1757 break;
1759 case EV_SW:
1760 __set_bit(code, dev->swbit);
1761 break;
1763 case EV_LED:
1764 __set_bit(code, dev->ledbit);
1765 break;
1767 case EV_SND:
1768 __set_bit(code, dev->sndbit);
1769 break;
1771 case EV_FF:
1772 __set_bit(code, dev->ffbit);
1773 break;
1775 case EV_PWR:
1776 /* do nothing */
1777 break;
1779 default:
1780 pr_err("input_set_capability: unknown type %u (code %u)\n",
1781 type, code);
1782 dump_stack();
1783 return;
1786 __set_bit(type, dev->evbit);
1788 EXPORT_SYMBOL(input_set_capability);
1790 #define INPUT_CLEANSE_BITMASK(dev, type, bits) \
1791 do { \
1792 if (!test_bit(EV_##type, dev->evbit)) \
1793 memset(dev->bits##bit, 0, \
1794 sizeof(dev->bits##bit)); \
1795 } while (0)
1797 static void input_cleanse_bitmasks(struct input_dev *dev)
1799 INPUT_CLEANSE_BITMASK(dev, KEY, key);
1800 INPUT_CLEANSE_BITMASK(dev, REL, rel);
1801 INPUT_CLEANSE_BITMASK(dev, ABS, abs);
1802 INPUT_CLEANSE_BITMASK(dev, MSC, msc);
1803 INPUT_CLEANSE_BITMASK(dev, LED, led);
1804 INPUT_CLEANSE_BITMASK(dev, SND, snd);
1805 INPUT_CLEANSE_BITMASK(dev, FF, ff);
1806 INPUT_CLEANSE_BITMASK(dev, SW, sw);
1810 * input_register_device - register device with input core
1811 * @dev: device to be registered
1813 * This function registers device with input core. The device must be
1814 * allocated with input_allocate_device() and all it's capabilities
1815 * set up before registering.
1816 * If function fails the device must be freed with input_free_device().
1817 * Once device has been successfully registered it can be unregistered
1818 * with input_unregister_device(); input_free_device() should not be
1819 * called in this case.
1821 int input_register_device(struct input_dev *dev)
1823 static atomic_t input_no = ATOMIC_INIT(0);
1824 struct input_handler *handler;
1825 const char *path;
1826 int error;
1828 /* Every input device generates EV_SYN/SYN_REPORT events. */
1829 __set_bit(EV_SYN, dev->evbit);
1831 /* KEY_RESERVED is not supposed to be transmitted to userspace. */
1832 __clear_bit(KEY_RESERVED, dev->keybit);
1834 /* Make sure that bitmasks not mentioned in dev->evbit are clean. */
1835 input_cleanse_bitmasks(dev);
1838 * If delay and period are pre-set by the driver, then autorepeating
1839 * is handled by the driver itself and we don't do it in input.c.
1841 init_timer(&dev->timer);
1842 if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
1843 dev->timer.data = (long) dev;
1844 dev->timer.function = input_repeat_key;
1845 dev->rep[REP_DELAY] = 250;
1846 dev->rep[REP_PERIOD] = 33;
1849 if (!dev->getkeycode && !dev->getkeycode_new)
1850 dev->getkeycode_new = input_default_getkeycode;
1852 if (!dev->setkeycode && !dev->setkeycode_new)
1853 dev->setkeycode_new = input_default_setkeycode;
1855 dev_set_name(&dev->dev, "input%ld",
1856 (unsigned long) atomic_inc_return(&input_no) - 1);
1858 error = device_add(&dev->dev);
1859 if (error)
1860 return error;
1862 path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1863 pr_info("%s as %s\n",
1864 dev->name ? dev->name : "Unspecified device",
1865 path ? path : "N/A");
1866 kfree(path);
1868 error = mutex_lock_interruptible(&input_mutex);
1869 if (error) {
1870 device_del(&dev->dev);
1871 return error;
1874 list_add_tail(&dev->node, &input_dev_list);
1876 list_for_each_entry(handler, &input_handler_list, node)
1877 input_attach_handler(dev, handler);
1879 input_wakeup_procfs_readers();
1881 mutex_unlock(&input_mutex);
1883 return 0;
1885 EXPORT_SYMBOL(input_register_device);
1888 * input_unregister_device - unregister previously registered device
1889 * @dev: device to be unregistered
1891 * This function unregisters an input device. Once device is unregistered
1892 * the caller should not try to access it as it may get freed at any moment.
1894 void input_unregister_device(struct input_dev *dev)
1896 struct input_handle *handle, *next;
1898 input_disconnect_device(dev);
1900 mutex_lock(&input_mutex);
1902 list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
1903 handle->handler->disconnect(handle);
1904 WARN_ON(!list_empty(&dev->h_list));
1906 del_timer_sync(&dev->timer);
1907 list_del_init(&dev->node);
1909 input_wakeup_procfs_readers();
1911 mutex_unlock(&input_mutex);
1913 device_unregister(&dev->dev);
1915 EXPORT_SYMBOL(input_unregister_device);
1918 * input_register_handler - register a new input handler
1919 * @handler: handler to be registered
1921 * This function registers a new input handler (interface) for input
1922 * devices in the system and attaches it to all input devices that
1923 * are compatible with the handler.
1925 int input_register_handler(struct input_handler *handler)
1927 struct input_dev *dev;
1928 int retval;
1930 retval = mutex_lock_interruptible(&input_mutex);
1931 if (retval)
1932 return retval;
1934 INIT_LIST_HEAD(&handler->h_list);
1936 if (handler->fops != NULL) {
1937 if (input_table[handler->minor >> 5]) {
1938 retval = -EBUSY;
1939 goto out;
1941 input_table[handler->minor >> 5] = handler;
1944 list_add_tail(&handler->node, &input_handler_list);
1946 list_for_each_entry(dev, &input_dev_list, node)
1947 input_attach_handler(dev, handler);
1949 input_wakeup_procfs_readers();
1951 out:
1952 mutex_unlock(&input_mutex);
1953 return retval;
1955 EXPORT_SYMBOL(input_register_handler);
1958 * input_unregister_handler - unregisters an input handler
1959 * @handler: handler to be unregistered
1961 * This function disconnects a handler from its input devices and
1962 * removes it from lists of known handlers.
1964 void input_unregister_handler(struct input_handler *handler)
1966 struct input_handle *handle, *next;
1968 mutex_lock(&input_mutex);
1970 list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
1971 handler->disconnect(handle);
1972 WARN_ON(!list_empty(&handler->h_list));
1974 list_del_init(&handler->node);
1976 if (handler->fops != NULL)
1977 input_table[handler->minor >> 5] = NULL;
1979 input_wakeup_procfs_readers();
1981 mutex_unlock(&input_mutex);
1983 EXPORT_SYMBOL(input_unregister_handler);
1986 * input_handler_for_each_handle - handle iterator
1987 * @handler: input handler to iterate
1988 * @data: data for the callback
1989 * @fn: function to be called for each handle
1991 * Iterate over @bus's list of devices, and call @fn for each, passing
1992 * it @data and stop when @fn returns a non-zero value. The function is
1993 * using RCU to traverse the list and therefore may be usind in atonic
1994 * contexts. The @fn callback is invoked from RCU critical section and
1995 * thus must not sleep.
1997 int input_handler_for_each_handle(struct input_handler *handler, void *data,
1998 int (*fn)(struct input_handle *, void *))
2000 struct input_handle *handle;
2001 int retval = 0;
2003 rcu_read_lock();
2005 list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
2006 retval = fn(handle, data);
2007 if (retval)
2008 break;
2011 rcu_read_unlock();
2013 return retval;
2015 EXPORT_SYMBOL(input_handler_for_each_handle);
2018 * input_register_handle - register a new input handle
2019 * @handle: handle to register
2021 * This function puts a new input handle onto device's
2022 * and handler's lists so that events can flow through
2023 * it once it is opened using input_open_device().
2025 * This function is supposed to be called from handler's
2026 * connect() method.
2028 int input_register_handle(struct input_handle *handle)
2030 struct input_handler *handler = handle->handler;
2031 struct input_dev *dev = handle->dev;
2032 int error;
2035 * We take dev->mutex here to prevent race with
2036 * input_release_device().
2038 error = mutex_lock_interruptible(&dev->mutex);
2039 if (error)
2040 return error;
2043 * Filters go to the head of the list, normal handlers
2044 * to the tail.
2046 if (handler->filter)
2047 list_add_rcu(&handle->d_node, &dev->h_list);
2048 else
2049 list_add_tail_rcu(&handle->d_node, &dev->h_list);
2051 mutex_unlock(&dev->mutex);
2054 * Since we are supposed to be called from ->connect()
2055 * which is mutually exclusive with ->disconnect()
2056 * we can't be racing with input_unregister_handle()
2057 * and so separate lock is not needed here.
2059 list_add_tail_rcu(&handle->h_node, &handler->h_list);
2061 if (handler->start)
2062 handler->start(handle);
2064 return 0;
2066 EXPORT_SYMBOL(input_register_handle);
2069 * input_unregister_handle - unregister an input handle
2070 * @handle: handle to unregister
2072 * This function removes input handle from device's
2073 * and handler's lists.
2075 * This function is supposed to be called from handler's
2076 * disconnect() method.
2078 void input_unregister_handle(struct input_handle *handle)
2080 struct input_dev *dev = handle->dev;
2082 list_del_rcu(&handle->h_node);
2085 * Take dev->mutex to prevent race with input_release_device().
2087 mutex_lock(&dev->mutex);
2088 list_del_rcu(&handle->d_node);
2089 mutex_unlock(&dev->mutex);
2091 synchronize_rcu();
2093 EXPORT_SYMBOL(input_unregister_handle);
2095 static int input_open_file(struct inode *inode, struct file *file)
2097 struct input_handler *handler;
2098 const struct file_operations *old_fops, *new_fops = NULL;
2099 int err;
2101 err = mutex_lock_interruptible(&input_mutex);
2102 if (err)
2103 return err;
2105 /* No load-on-demand here? */
2106 handler = input_table[iminor(inode) >> 5];
2107 if (handler)
2108 new_fops = fops_get(handler->fops);
2110 mutex_unlock(&input_mutex);
2113 * That's _really_ odd. Usually NULL ->open means "nothing special",
2114 * not "no device". Oh, well...
2116 if (!new_fops || !new_fops->open) {
2117 fops_put(new_fops);
2118 err = -ENODEV;
2119 goto out;
2122 old_fops = file->f_op;
2123 file->f_op = new_fops;
2125 err = new_fops->open(inode, file);
2126 if (err) {
2127 fops_put(file->f_op);
2128 file->f_op = fops_get(old_fops);
2130 fops_put(old_fops);
2131 out:
2132 return err;
2135 static const struct file_operations input_fops = {
2136 .owner = THIS_MODULE,
2137 .open = input_open_file,
2138 .llseek = noop_llseek,
2141 static int __init input_init(void)
2143 int err;
2145 err = class_register(&input_class);
2146 if (err) {
2147 pr_err("unable to register input_dev class\n");
2148 return err;
2151 err = input_proc_init();
2152 if (err)
2153 goto fail1;
2155 err = register_chrdev(INPUT_MAJOR, "input", &input_fops);
2156 if (err) {
2157 pr_err("unable to register char major %d", INPUT_MAJOR);
2158 goto fail2;
2161 return 0;
2163 fail2: input_proc_exit();
2164 fail1: class_unregister(&input_class);
2165 return err;
2168 static void __exit input_exit(void)
2170 input_proc_exit();
2171 unregister_chrdev(INPUT_MAJOR, "input");
2172 class_unregister(&input_class);
2175 subsys_initcall(input_init);
2176 module_exit(input_exit);