Btrfs: stop the readahead threads on failed mount
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / input / input.c
blobda38d97a51b1c67782f3265a19bac3cdb5fd2686
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);
455 out:
456 mutex_unlock(&dev->mutex);
457 return retval;
459 EXPORT_SYMBOL(input_grab_device);
461 static void __input_release_device(struct input_handle *handle)
463 struct input_dev *dev = handle->dev;
465 if (dev->grab == handle) {
466 rcu_assign_pointer(dev->grab, NULL);
467 /* Make sure input_pass_event() notices that grab is gone */
468 synchronize_rcu();
470 list_for_each_entry(handle, &dev->h_list, d_node)
471 if (handle->open && handle->handler->start)
472 handle->handler->start(handle);
477 * input_release_device - release previously grabbed device
478 * @handle: input handle that owns the device
480 * Releases previously grabbed device so that other input handles can
481 * start receiving input events. Upon release all handlers attached
482 * to the device have their start() method called so they have a change
483 * to synchronize device state with the rest of the system.
485 void input_release_device(struct input_handle *handle)
487 struct input_dev *dev = handle->dev;
489 mutex_lock(&dev->mutex);
490 __input_release_device(handle);
491 mutex_unlock(&dev->mutex);
493 EXPORT_SYMBOL(input_release_device);
496 * input_open_device - open input device
497 * @handle: handle through which device is being accessed
499 * This function should be called by input handlers when they
500 * want to start receive events from given input device.
502 int input_open_device(struct input_handle *handle)
504 struct input_dev *dev = handle->dev;
505 int retval;
507 retval = mutex_lock_interruptible(&dev->mutex);
508 if (retval)
509 return retval;
511 if (dev->going_away) {
512 retval = -ENODEV;
513 goto out;
516 handle->open++;
518 if (!dev->users++ && dev->open)
519 retval = dev->open(dev);
521 if (retval) {
522 dev->users--;
523 if (!--handle->open) {
525 * Make sure we are not delivering any more events
526 * through this handle
528 synchronize_rcu();
532 out:
533 mutex_unlock(&dev->mutex);
534 return retval;
536 EXPORT_SYMBOL(input_open_device);
538 int input_flush_device(struct input_handle *handle, struct file *file)
540 struct input_dev *dev = handle->dev;
541 int retval;
543 retval = mutex_lock_interruptible(&dev->mutex);
544 if (retval)
545 return retval;
547 if (dev->flush)
548 retval = dev->flush(dev, file);
550 mutex_unlock(&dev->mutex);
551 return retval;
553 EXPORT_SYMBOL(input_flush_device);
556 * input_close_device - close input device
557 * @handle: handle through which device is being accessed
559 * This function should be called by input handlers when they
560 * want to stop receive events from given input device.
562 void input_close_device(struct input_handle *handle)
564 struct input_dev *dev = handle->dev;
566 mutex_lock(&dev->mutex);
568 __input_release_device(handle);
570 if (!--dev->users && dev->close)
571 dev->close(dev);
573 if (!--handle->open) {
575 * synchronize_rcu() makes sure that input_pass_event()
576 * completed and that no more input events are delivered
577 * through this handle
579 synchronize_rcu();
582 mutex_unlock(&dev->mutex);
584 EXPORT_SYMBOL(input_close_device);
587 * Simulate keyup events for all keys that are marked as pressed.
588 * The function must be called with dev->event_lock held.
590 static void input_dev_release_keys(struct input_dev *dev)
592 int code;
594 if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
595 for (code = 0; code <= KEY_MAX; code++) {
596 if (is_event_supported(code, dev->keybit, KEY_MAX) &&
597 __test_and_clear_bit(code, dev->key)) {
598 input_pass_event(dev, EV_KEY, code, 0);
601 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
606 * Prepare device for unregistering
608 static void input_disconnect_device(struct input_dev *dev)
610 struct input_handle *handle;
613 * Mark device as going away. Note that we take dev->mutex here
614 * not to protect access to dev->going_away but rather to ensure
615 * that there are no threads in the middle of input_open_device()
617 mutex_lock(&dev->mutex);
618 dev->going_away = true;
619 mutex_unlock(&dev->mutex);
621 spin_lock_irq(&dev->event_lock);
624 * Simulate keyup events for all pressed keys so that handlers
625 * are not left with "stuck" keys. The driver may continue
626 * generate events even after we done here but they will not
627 * reach any handlers.
629 input_dev_release_keys(dev);
631 list_for_each_entry(handle, &dev->h_list, d_node)
632 handle->open = 0;
634 spin_unlock_irq(&dev->event_lock);
638 * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
639 * @ke: keymap entry containing scancode to be converted.
640 * @scancode: pointer to the location where converted scancode should
641 * be stored.
643 * This function is used to convert scancode stored in &struct keymap_entry
644 * into scalar form understood by legacy keymap handling methods. These
645 * methods expect scancodes to be represented as 'unsigned int'.
647 int input_scancode_to_scalar(const struct input_keymap_entry *ke,
648 unsigned int *scancode)
650 switch (ke->len) {
651 case 1:
652 *scancode = *((u8 *)ke->scancode);
653 break;
655 case 2:
656 *scancode = *((u16 *)ke->scancode);
657 break;
659 case 4:
660 *scancode = *((u32 *)ke->scancode);
661 break;
663 default:
664 return -EINVAL;
667 return 0;
669 EXPORT_SYMBOL(input_scancode_to_scalar);
672 * Those routines handle the default case where no [gs]etkeycode() is
673 * defined. In this case, an array indexed by the scancode is used.
676 static unsigned int input_fetch_keycode(struct input_dev *dev,
677 unsigned int index)
679 switch (dev->keycodesize) {
680 case 1:
681 return ((u8 *)dev->keycode)[index];
683 case 2:
684 return ((u16 *)dev->keycode)[index];
686 default:
687 return ((u32 *)dev->keycode)[index];
691 static int input_default_getkeycode(struct input_dev *dev,
692 struct input_keymap_entry *ke)
694 unsigned int index;
695 int error;
697 if (!dev->keycodesize)
698 return -EINVAL;
700 if (ke->flags & INPUT_KEYMAP_BY_INDEX)
701 index = ke->index;
702 else {
703 error = input_scancode_to_scalar(ke, &index);
704 if (error)
705 return error;
708 if (index >= dev->keycodemax)
709 return -EINVAL;
711 ke->keycode = input_fetch_keycode(dev, index);
712 ke->index = index;
713 ke->len = sizeof(index);
714 memcpy(ke->scancode, &index, sizeof(index));
716 return 0;
719 static int input_default_setkeycode(struct input_dev *dev,
720 const struct input_keymap_entry *ke,
721 unsigned int *old_keycode)
723 unsigned int index;
724 int error;
725 int i;
727 if (!dev->keycodesize)
728 return -EINVAL;
730 if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
731 index = ke->index;
732 } else {
733 error = input_scancode_to_scalar(ke, &index);
734 if (error)
735 return error;
738 if (index >= dev->keycodemax)
739 return -EINVAL;
741 if (dev->keycodesize < sizeof(ke->keycode) &&
742 (ke->keycode >> (dev->keycodesize * 8)))
743 return -EINVAL;
745 switch (dev->keycodesize) {
746 case 1: {
747 u8 *k = (u8 *)dev->keycode;
748 *old_keycode = k[index];
749 k[index] = ke->keycode;
750 break;
752 case 2: {
753 u16 *k = (u16 *)dev->keycode;
754 *old_keycode = k[index];
755 k[index] = ke->keycode;
756 break;
758 default: {
759 u32 *k = (u32 *)dev->keycode;
760 *old_keycode = k[index];
761 k[index] = ke->keycode;
762 break;
766 __clear_bit(*old_keycode, dev->keybit);
767 __set_bit(ke->keycode, dev->keybit);
769 for (i = 0; i < dev->keycodemax; i++) {
770 if (input_fetch_keycode(dev, i) == *old_keycode) {
771 __set_bit(*old_keycode, dev->keybit);
772 break; /* Setting the bit twice is useless, so break */
776 return 0;
780 * input_get_keycode - retrieve keycode currently mapped to a given scancode
781 * @dev: input device which keymap is being queried
782 * @ke: keymap entry
784 * This function should be called by anyone interested in retrieving current
785 * keymap. Presently evdev handlers use it.
787 int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
789 unsigned long flags;
790 int retval;
792 spin_lock_irqsave(&dev->event_lock, flags);
793 retval = dev->getkeycode(dev, ke);
794 spin_unlock_irqrestore(&dev->event_lock, flags);
796 return retval;
798 EXPORT_SYMBOL(input_get_keycode);
801 * input_set_keycode - attribute a keycode to a given scancode
802 * @dev: input device which keymap is being updated
803 * @ke: new keymap entry
805 * This function should be called by anyone needing to update current
806 * keymap. Presently keyboard and evdev handlers use it.
808 int input_set_keycode(struct input_dev *dev,
809 const struct input_keymap_entry *ke)
811 unsigned long flags;
812 unsigned int old_keycode;
813 int retval;
815 if (ke->keycode > KEY_MAX)
816 return -EINVAL;
818 spin_lock_irqsave(&dev->event_lock, flags);
820 retval = dev->setkeycode(dev, ke, &old_keycode);
821 if (retval)
822 goto out;
824 /* Make sure KEY_RESERVED did not get enabled. */
825 __clear_bit(KEY_RESERVED, dev->keybit);
828 * Simulate keyup event if keycode is not present
829 * in the keymap anymore
831 if (test_bit(EV_KEY, dev->evbit) &&
832 !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
833 __test_and_clear_bit(old_keycode, dev->key)) {
835 input_pass_event(dev, EV_KEY, old_keycode, 0);
836 if (dev->sync)
837 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
840 out:
841 spin_unlock_irqrestore(&dev->event_lock, flags);
843 return retval;
845 EXPORT_SYMBOL(input_set_keycode);
847 #define MATCH_BIT(bit, max) \
848 for (i = 0; i < BITS_TO_LONGS(max); i++) \
849 if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \
850 break; \
851 if (i != BITS_TO_LONGS(max)) \
852 continue;
854 static const struct input_device_id *input_match_device(struct input_handler *handler,
855 struct input_dev *dev)
857 const struct input_device_id *id;
858 int i;
860 for (id = handler->id_table; id->flags || id->driver_info; id++) {
862 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
863 if (id->bustype != dev->id.bustype)
864 continue;
866 if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
867 if (id->vendor != dev->id.vendor)
868 continue;
870 if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
871 if (id->product != dev->id.product)
872 continue;
874 if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
875 if (id->version != dev->id.version)
876 continue;
878 MATCH_BIT(evbit, EV_MAX);
879 MATCH_BIT(keybit, KEY_MAX);
880 MATCH_BIT(relbit, REL_MAX);
881 MATCH_BIT(absbit, ABS_MAX);
882 MATCH_BIT(mscbit, MSC_MAX);
883 MATCH_BIT(ledbit, LED_MAX);
884 MATCH_BIT(sndbit, SND_MAX);
885 MATCH_BIT(ffbit, FF_MAX);
886 MATCH_BIT(swbit, SW_MAX);
888 if (!handler->match || handler->match(handler, dev))
889 return id;
892 return NULL;
895 static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
897 const struct input_device_id *id;
898 int error;
900 id = input_match_device(handler, dev);
901 if (!id)
902 return -ENODEV;
904 error = handler->connect(handler, dev, id);
905 if (error && error != -ENODEV)
906 pr_err("failed to attach handler %s to device %s, error: %d\n",
907 handler->name, kobject_name(&dev->dev.kobj), error);
909 return error;
912 #ifdef CONFIG_COMPAT
914 static int input_bits_to_string(char *buf, int buf_size,
915 unsigned long bits, bool skip_empty)
917 int len = 0;
919 if (INPUT_COMPAT_TEST) {
920 u32 dword = bits >> 32;
921 if (dword || !skip_empty)
922 len += snprintf(buf, buf_size, "%x ", dword);
924 dword = bits & 0xffffffffUL;
925 if (dword || !skip_empty || len)
926 len += snprintf(buf + len, max(buf_size - len, 0),
927 "%x", dword);
928 } else {
929 if (bits || !skip_empty)
930 len += snprintf(buf, buf_size, "%lx", bits);
933 return len;
936 #else /* !CONFIG_COMPAT */
938 static int input_bits_to_string(char *buf, int buf_size,
939 unsigned long bits, bool skip_empty)
941 return bits || !skip_empty ?
942 snprintf(buf, buf_size, "%lx", bits) : 0;
945 #endif
947 #ifdef CONFIG_PROC_FS
949 static struct proc_dir_entry *proc_bus_input_dir;
950 static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
951 static int input_devices_state;
953 static inline void input_wakeup_procfs_readers(void)
955 input_devices_state++;
956 wake_up(&input_devices_poll_wait);
959 static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
961 poll_wait(file, &input_devices_poll_wait, wait);
962 if (file->f_version != input_devices_state) {
963 file->f_version = input_devices_state;
964 return POLLIN | POLLRDNORM;
967 return 0;
970 union input_seq_state {
971 struct {
972 unsigned short pos;
973 bool mutex_acquired;
975 void *p;
978 static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
980 union input_seq_state *state = (union input_seq_state *)&seq->private;
981 int error;
983 /* We need to fit into seq->private pointer */
984 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
986 error = mutex_lock_interruptible(&input_mutex);
987 if (error) {
988 state->mutex_acquired = false;
989 return ERR_PTR(error);
992 state->mutex_acquired = true;
994 return seq_list_start(&input_dev_list, *pos);
997 static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
999 return seq_list_next(v, &input_dev_list, pos);
1002 static void input_seq_stop(struct seq_file *seq, void *v)
1004 union input_seq_state *state = (union input_seq_state *)&seq->private;
1006 if (state->mutex_acquired)
1007 mutex_unlock(&input_mutex);
1010 static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
1011 unsigned long *bitmap, int max)
1013 int i;
1014 bool skip_empty = true;
1015 char buf[18];
1017 seq_printf(seq, "B: %s=", name);
1019 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1020 if (input_bits_to_string(buf, sizeof(buf),
1021 bitmap[i], skip_empty)) {
1022 skip_empty = false;
1023 seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
1028 * If no output was produced print a single 0.
1030 if (skip_empty)
1031 seq_puts(seq, "0");
1033 seq_putc(seq, '\n');
1036 static int input_devices_seq_show(struct seq_file *seq, void *v)
1038 struct input_dev *dev = container_of(v, struct input_dev, node);
1039 const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1040 struct input_handle *handle;
1042 seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
1043 dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
1045 seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
1046 seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
1047 seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
1048 seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1049 seq_printf(seq, "H: Handlers=");
1051 list_for_each_entry(handle, &dev->h_list, d_node)
1052 seq_printf(seq, "%s ", handle->name);
1053 seq_putc(seq, '\n');
1055 input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
1057 input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
1058 if (test_bit(EV_KEY, dev->evbit))
1059 input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
1060 if (test_bit(EV_REL, dev->evbit))
1061 input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
1062 if (test_bit(EV_ABS, dev->evbit))
1063 input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
1064 if (test_bit(EV_MSC, dev->evbit))
1065 input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
1066 if (test_bit(EV_LED, dev->evbit))
1067 input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
1068 if (test_bit(EV_SND, dev->evbit))
1069 input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
1070 if (test_bit(EV_FF, dev->evbit))
1071 input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
1072 if (test_bit(EV_SW, dev->evbit))
1073 input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
1075 seq_putc(seq, '\n');
1077 kfree(path);
1078 return 0;
1081 static const struct seq_operations input_devices_seq_ops = {
1082 .start = input_devices_seq_start,
1083 .next = input_devices_seq_next,
1084 .stop = input_seq_stop,
1085 .show = input_devices_seq_show,
1088 static int input_proc_devices_open(struct inode *inode, struct file *file)
1090 return seq_open(file, &input_devices_seq_ops);
1093 static const struct file_operations input_devices_fileops = {
1094 .owner = THIS_MODULE,
1095 .open = input_proc_devices_open,
1096 .poll = input_proc_devices_poll,
1097 .read = seq_read,
1098 .llseek = seq_lseek,
1099 .release = seq_release,
1102 static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
1104 union input_seq_state *state = (union input_seq_state *)&seq->private;
1105 int error;
1107 /* We need to fit into seq->private pointer */
1108 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1110 error = mutex_lock_interruptible(&input_mutex);
1111 if (error) {
1112 state->mutex_acquired = false;
1113 return ERR_PTR(error);
1116 state->mutex_acquired = true;
1117 state->pos = *pos;
1119 return seq_list_start(&input_handler_list, *pos);
1122 static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1124 union input_seq_state *state = (union input_seq_state *)&seq->private;
1126 state->pos = *pos + 1;
1127 return seq_list_next(v, &input_handler_list, pos);
1130 static int input_handlers_seq_show(struct seq_file *seq, void *v)
1132 struct input_handler *handler = container_of(v, struct input_handler, node);
1133 union input_seq_state *state = (union input_seq_state *)&seq->private;
1135 seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
1136 if (handler->filter)
1137 seq_puts(seq, " (filter)");
1138 if (handler->fops)
1139 seq_printf(seq, " Minor=%d", handler->minor);
1140 seq_putc(seq, '\n');
1142 return 0;
1145 static const struct seq_operations input_handlers_seq_ops = {
1146 .start = input_handlers_seq_start,
1147 .next = input_handlers_seq_next,
1148 .stop = input_seq_stop,
1149 .show = input_handlers_seq_show,
1152 static int input_proc_handlers_open(struct inode *inode, struct file *file)
1154 return seq_open(file, &input_handlers_seq_ops);
1157 static const struct file_operations input_handlers_fileops = {
1158 .owner = THIS_MODULE,
1159 .open = input_proc_handlers_open,
1160 .read = seq_read,
1161 .llseek = seq_lseek,
1162 .release = seq_release,
1165 static int __init input_proc_init(void)
1167 struct proc_dir_entry *entry;
1169 proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1170 if (!proc_bus_input_dir)
1171 return -ENOMEM;
1173 entry = proc_create("devices", 0, proc_bus_input_dir,
1174 &input_devices_fileops);
1175 if (!entry)
1176 goto fail1;
1178 entry = proc_create("handlers", 0, proc_bus_input_dir,
1179 &input_handlers_fileops);
1180 if (!entry)
1181 goto fail2;
1183 return 0;
1185 fail2: remove_proc_entry("devices", proc_bus_input_dir);
1186 fail1: remove_proc_entry("bus/input", NULL);
1187 return -ENOMEM;
1190 static void input_proc_exit(void)
1192 remove_proc_entry("devices", proc_bus_input_dir);
1193 remove_proc_entry("handlers", proc_bus_input_dir);
1194 remove_proc_entry("bus/input", NULL);
1197 #else /* !CONFIG_PROC_FS */
1198 static inline void input_wakeup_procfs_readers(void) { }
1199 static inline int input_proc_init(void) { return 0; }
1200 static inline void input_proc_exit(void) { }
1201 #endif
1203 #define INPUT_DEV_STRING_ATTR_SHOW(name) \
1204 static ssize_t input_dev_show_##name(struct device *dev, \
1205 struct device_attribute *attr, \
1206 char *buf) \
1208 struct input_dev *input_dev = to_input_dev(dev); \
1210 return scnprintf(buf, PAGE_SIZE, "%s\n", \
1211 input_dev->name ? input_dev->name : ""); \
1213 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1215 INPUT_DEV_STRING_ATTR_SHOW(name);
1216 INPUT_DEV_STRING_ATTR_SHOW(phys);
1217 INPUT_DEV_STRING_ATTR_SHOW(uniq);
1219 static int input_print_modalias_bits(char *buf, int size,
1220 char name, unsigned long *bm,
1221 unsigned int min_bit, unsigned int max_bit)
1223 int len = 0, i;
1225 len += snprintf(buf, max(size, 0), "%c", name);
1226 for (i = min_bit; i < max_bit; i++)
1227 if (bm[BIT_WORD(i)] & BIT_MASK(i))
1228 len += snprintf(buf + len, max(size - len, 0), "%X,", i);
1229 return len;
1232 static int input_print_modalias(char *buf, int size, struct input_dev *id,
1233 int add_cr)
1235 int len;
1237 len = snprintf(buf, max(size, 0),
1238 "input:b%04Xv%04Xp%04Xe%04X-",
1239 id->id.bustype, id->id.vendor,
1240 id->id.product, id->id.version);
1242 len += input_print_modalias_bits(buf + len, size - len,
1243 'e', id->evbit, 0, EV_MAX);
1244 len += input_print_modalias_bits(buf + len, size - len,
1245 'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1246 len += input_print_modalias_bits(buf + len, size - len,
1247 'r', id->relbit, 0, REL_MAX);
1248 len += input_print_modalias_bits(buf + len, size - len,
1249 'a', id->absbit, 0, ABS_MAX);
1250 len += input_print_modalias_bits(buf + len, size - len,
1251 'm', id->mscbit, 0, MSC_MAX);
1252 len += input_print_modalias_bits(buf + len, size - len,
1253 'l', id->ledbit, 0, LED_MAX);
1254 len += input_print_modalias_bits(buf + len, size - len,
1255 's', id->sndbit, 0, SND_MAX);
1256 len += input_print_modalias_bits(buf + len, size - len,
1257 'f', id->ffbit, 0, FF_MAX);
1258 len += input_print_modalias_bits(buf + len, size - len,
1259 'w', id->swbit, 0, SW_MAX);
1261 if (add_cr)
1262 len += snprintf(buf + len, max(size - len, 0), "\n");
1264 return len;
1267 static ssize_t input_dev_show_modalias(struct device *dev,
1268 struct device_attribute *attr,
1269 char *buf)
1271 struct input_dev *id = to_input_dev(dev);
1272 ssize_t len;
1274 len = input_print_modalias(buf, PAGE_SIZE, id, 1);
1276 return min_t(int, len, PAGE_SIZE);
1278 static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1280 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1281 int max, int add_cr);
1283 static ssize_t input_dev_show_properties(struct device *dev,
1284 struct device_attribute *attr,
1285 char *buf)
1287 struct input_dev *input_dev = to_input_dev(dev);
1288 int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
1289 INPUT_PROP_MAX, true);
1290 return min_t(int, len, PAGE_SIZE);
1292 static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
1294 static struct attribute *input_dev_attrs[] = {
1295 &dev_attr_name.attr,
1296 &dev_attr_phys.attr,
1297 &dev_attr_uniq.attr,
1298 &dev_attr_modalias.attr,
1299 &dev_attr_properties.attr,
1300 NULL
1303 static struct attribute_group input_dev_attr_group = {
1304 .attrs = input_dev_attrs,
1307 #define INPUT_DEV_ID_ATTR(name) \
1308 static ssize_t input_dev_show_id_##name(struct device *dev, \
1309 struct device_attribute *attr, \
1310 char *buf) \
1312 struct input_dev *input_dev = to_input_dev(dev); \
1313 return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name); \
1315 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1317 INPUT_DEV_ID_ATTR(bustype);
1318 INPUT_DEV_ID_ATTR(vendor);
1319 INPUT_DEV_ID_ATTR(product);
1320 INPUT_DEV_ID_ATTR(version);
1322 static struct attribute *input_dev_id_attrs[] = {
1323 &dev_attr_bustype.attr,
1324 &dev_attr_vendor.attr,
1325 &dev_attr_product.attr,
1326 &dev_attr_version.attr,
1327 NULL
1330 static struct attribute_group input_dev_id_attr_group = {
1331 .name = "id",
1332 .attrs = input_dev_id_attrs,
1335 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1336 int max, int add_cr)
1338 int i;
1339 int len = 0;
1340 bool skip_empty = true;
1342 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1343 len += input_bits_to_string(buf + len, max(buf_size - len, 0),
1344 bitmap[i], skip_empty);
1345 if (len) {
1346 skip_empty = false;
1347 if (i > 0)
1348 len += snprintf(buf + len, max(buf_size - len, 0), " ");
1353 * If no output was produced print a single 0.
1355 if (len == 0)
1356 len = snprintf(buf, buf_size, "%d", 0);
1358 if (add_cr)
1359 len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1361 return len;
1364 #define INPUT_DEV_CAP_ATTR(ev, bm) \
1365 static ssize_t input_dev_show_cap_##bm(struct device *dev, \
1366 struct device_attribute *attr, \
1367 char *buf) \
1369 struct input_dev *input_dev = to_input_dev(dev); \
1370 int len = input_print_bitmap(buf, PAGE_SIZE, \
1371 input_dev->bm##bit, ev##_MAX, \
1372 true); \
1373 return min_t(int, len, PAGE_SIZE); \
1375 static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1377 INPUT_DEV_CAP_ATTR(EV, ev);
1378 INPUT_DEV_CAP_ATTR(KEY, key);
1379 INPUT_DEV_CAP_ATTR(REL, rel);
1380 INPUT_DEV_CAP_ATTR(ABS, abs);
1381 INPUT_DEV_CAP_ATTR(MSC, msc);
1382 INPUT_DEV_CAP_ATTR(LED, led);
1383 INPUT_DEV_CAP_ATTR(SND, snd);
1384 INPUT_DEV_CAP_ATTR(FF, ff);
1385 INPUT_DEV_CAP_ATTR(SW, sw);
1387 static struct attribute *input_dev_caps_attrs[] = {
1388 &dev_attr_ev.attr,
1389 &dev_attr_key.attr,
1390 &dev_attr_rel.attr,
1391 &dev_attr_abs.attr,
1392 &dev_attr_msc.attr,
1393 &dev_attr_led.attr,
1394 &dev_attr_snd.attr,
1395 &dev_attr_ff.attr,
1396 &dev_attr_sw.attr,
1397 NULL
1400 static struct attribute_group input_dev_caps_attr_group = {
1401 .name = "capabilities",
1402 .attrs = input_dev_caps_attrs,
1405 static const struct attribute_group *input_dev_attr_groups[] = {
1406 &input_dev_attr_group,
1407 &input_dev_id_attr_group,
1408 &input_dev_caps_attr_group,
1409 NULL
1412 static void input_dev_release(struct device *device)
1414 struct input_dev *dev = to_input_dev(device);
1416 input_ff_destroy(dev);
1417 input_mt_destroy_slots(dev);
1418 kfree(dev->absinfo);
1419 kfree(dev);
1421 module_put(THIS_MODULE);
1425 * Input uevent interface - loading event handlers based on
1426 * device bitfields.
1428 static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1429 const char *name, unsigned long *bitmap, int max)
1431 int len;
1433 if (add_uevent_var(env, "%s", name))
1434 return -ENOMEM;
1436 len = input_print_bitmap(&env->buf[env->buflen - 1],
1437 sizeof(env->buf) - env->buflen,
1438 bitmap, max, false);
1439 if (len >= (sizeof(env->buf) - env->buflen))
1440 return -ENOMEM;
1442 env->buflen += len;
1443 return 0;
1446 static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1447 struct input_dev *dev)
1449 int len;
1451 if (add_uevent_var(env, "MODALIAS="))
1452 return -ENOMEM;
1454 len = input_print_modalias(&env->buf[env->buflen - 1],
1455 sizeof(env->buf) - env->buflen,
1456 dev, 0);
1457 if (len >= (sizeof(env->buf) - env->buflen))
1458 return -ENOMEM;
1460 env->buflen += len;
1461 return 0;
1464 #define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \
1465 do { \
1466 int err = add_uevent_var(env, fmt, val); \
1467 if (err) \
1468 return err; \
1469 } while (0)
1471 #define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max) \
1472 do { \
1473 int err = input_add_uevent_bm_var(env, name, bm, max); \
1474 if (err) \
1475 return err; \
1476 } while (0)
1478 #define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \
1479 do { \
1480 int err = input_add_uevent_modalias_var(env, dev); \
1481 if (err) \
1482 return err; \
1483 } while (0)
1485 static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
1487 struct input_dev *dev = to_input_dev(device);
1489 INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1490 dev->id.bustype, dev->id.vendor,
1491 dev->id.product, dev->id.version);
1492 if (dev->name)
1493 INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1494 if (dev->phys)
1495 INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1496 if (dev->uniq)
1497 INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1499 INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
1501 INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1502 if (test_bit(EV_KEY, dev->evbit))
1503 INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1504 if (test_bit(EV_REL, dev->evbit))
1505 INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1506 if (test_bit(EV_ABS, dev->evbit))
1507 INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1508 if (test_bit(EV_MSC, dev->evbit))
1509 INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1510 if (test_bit(EV_LED, dev->evbit))
1511 INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1512 if (test_bit(EV_SND, dev->evbit))
1513 INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1514 if (test_bit(EV_FF, dev->evbit))
1515 INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1516 if (test_bit(EV_SW, dev->evbit))
1517 INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1519 INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1521 return 0;
1524 #define INPUT_DO_TOGGLE(dev, type, bits, on) \
1525 do { \
1526 int i; \
1527 bool active; \
1529 if (!test_bit(EV_##type, dev->evbit)) \
1530 break; \
1532 for (i = 0; i < type##_MAX; i++) { \
1533 if (!test_bit(i, dev->bits##bit)) \
1534 continue; \
1536 active = test_bit(i, dev->bits); \
1537 if (!active && !on) \
1538 continue; \
1540 dev->event(dev, EV_##type, i, on ? active : 0); \
1542 } while (0)
1544 static void input_dev_toggle(struct input_dev *dev, bool activate)
1546 if (!dev->event)
1547 return;
1549 INPUT_DO_TOGGLE(dev, LED, led, activate);
1550 INPUT_DO_TOGGLE(dev, SND, snd, activate);
1552 if (activate && test_bit(EV_REP, dev->evbit)) {
1553 dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1554 dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1559 * input_reset_device() - reset/restore the state of input device
1560 * @dev: input device whose state needs to be reset
1562 * This function tries to reset the state of an opened input device and
1563 * bring internal state and state if the hardware in sync with each other.
1564 * We mark all keys as released, restore LED state, repeat rate, etc.
1566 void input_reset_device(struct input_dev *dev)
1568 mutex_lock(&dev->mutex);
1570 if (dev->users) {
1571 input_dev_toggle(dev, true);
1574 * Keys that have been pressed at suspend time are unlikely
1575 * to be still pressed when we resume.
1577 spin_lock_irq(&dev->event_lock);
1578 input_dev_release_keys(dev);
1579 spin_unlock_irq(&dev->event_lock);
1582 mutex_unlock(&dev->mutex);
1584 EXPORT_SYMBOL(input_reset_device);
1586 #ifdef CONFIG_PM
1587 static int input_dev_suspend(struct device *dev)
1589 struct input_dev *input_dev = to_input_dev(dev);
1591 mutex_lock(&input_dev->mutex);
1593 if (input_dev->users)
1594 input_dev_toggle(input_dev, false);
1596 mutex_unlock(&input_dev->mutex);
1598 return 0;
1601 static int input_dev_resume(struct device *dev)
1603 struct input_dev *input_dev = to_input_dev(dev);
1605 input_reset_device(input_dev);
1607 return 0;
1610 static const struct dev_pm_ops input_dev_pm_ops = {
1611 .suspend = input_dev_suspend,
1612 .resume = input_dev_resume,
1613 .poweroff = input_dev_suspend,
1614 .restore = input_dev_resume,
1616 #endif /* CONFIG_PM */
1618 static struct device_type input_dev_type = {
1619 .groups = input_dev_attr_groups,
1620 .release = input_dev_release,
1621 .uevent = input_dev_uevent,
1622 #ifdef CONFIG_PM
1623 .pm = &input_dev_pm_ops,
1624 #endif
1627 static char *input_devnode(struct device *dev, mode_t *mode)
1629 return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
1632 struct class input_class = {
1633 .name = "input",
1634 .devnode = input_devnode,
1636 EXPORT_SYMBOL_GPL(input_class);
1639 * input_allocate_device - allocate memory for new input device
1641 * Returns prepared struct input_dev or NULL.
1643 * NOTE: Use input_free_device() to free devices that have not been
1644 * registered; input_unregister_device() should be used for already
1645 * registered devices.
1647 struct input_dev *input_allocate_device(void)
1649 struct input_dev *dev;
1651 dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
1652 if (dev) {
1653 dev->dev.type = &input_dev_type;
1654 dev->dev.class = &input_class;
1655 device_initialize(&dev->dev);
1656 mutex_init(&dev->mutex);
1657 spin_lock_init(&dev->event_lock);
1658 INIT_LIST_HEAD(&dev->h_list);
1659 INIT_LIST_HEAD(&dev->node);
1661 __module_get(THIS_MODULE);
1664 return dev;
1666 EXPORT_SYMBOL(input_allocate_device);
1669 * input_free_device - free memory occupied by input_dev structure
1670 * @dev: input device to free
1672 * This function should only be used if input_register_device()
1673 * was not called yet or if it failed. Once device was registered
1674 * use input_unregister_device() and memory will be freed once last
1675 * reference to the device is dropped.
1677 * Device should be allocated by input_allocate_device().
1679 * NOTE: If there are references to the input device then memory
1680 * will not be freed until last reference is dropped.
1682 void input_free_device(struct input_dev *dev)
1684 if (dev)
1685 input_put_device(dev);
1687 EXPORT_SYMBOL(input_free_device);
1690 * input_set_capability - mark device as capable of a certain event
1691 * @dev: device that is capable of emitting or accepting event
1692 * @type: type of the event (EV_KEY, EV_REL, etc...)
1693 * @code: event code
1695 * In addition to setting up corresponding bit in appropriate capability
1696 * bitmap the function also adjusts dev->evbit.
1698 void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
1700 switch (type) {
1701 case EV_KEY:
1702 __set_bit(code, dev->keybit);
1703 break;
1705 case EV_REL:
1706 __set_bit(code, dev->relbit);
1707 break;
1709 case EV_ABS:
1710 __set_bit(code, dev->absbit);
1711 break;
1713 case EV_MSC:
1714 __set_bit(code, dev->mscbit);
1715 break;
1717 case EV_SW:
1718 __set_bit(code, dev->swbit);
1719 break;
1721 case EV_LED:
1722 __set_bit(code, dev->ledbit);
1723 break;
1725 case EV_SND:
1726 __set_bit(code, dev->sndbit);
1727 break;
1729 case EV_FF:
1730 __set_bit(code, dev->ffbit);
1731 break;
1733 case EV_PWR:
1734 /* do nothing */
1735 break;
1737 default:
1738 pr_err("input_set_capability: unknown type %u (code %u)\n",
1739 type, code);
1740 dump_stack();
1741 return;
1744 __set_bit(type, dev->evbit);
1746 EXPORT_SYMBOL(input_set_capability);
1748 static unsigned int input_estimate_events_per_packet(struct input_dev *dev)
1750 int mt_slots;
1751 int i;
1752 unsigned int events;
1754 if (dev->mtsize) {
1755 mt_slots = dev->mtsize;
1756 } else if (test_bit(ABS_MT_TRACKING_ID, dev->absbit)) {
1757 mt_slots = dev->absinfo[ABS_MT_TRACKING_ID].maximum -
1758 dev->absinfo[ABS_MT_TRACKING_ID].minimum + 1,
1759 mt_slots = clamp(mt_slots, 2, 32);
1760 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
1761 mt_slots = 2;
1762 } else {
1763 mt_slots = 0;
1766 events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */
1768 for (i = 0; i < ABS_CNT; i++) {
1769 if (test_bit(i, dev->absbit)) {
1770 if (input_is_mt_axis(i))
1771 events += mt_slots;
1772 else
1773 events++;
1777 for (i = 0; i < REL_CNT; i++)
1778 if (test_bit(i, dev->relbit))
1779 events++;
1781 return events;
1784 #define INPUT_CLEANSE_BITMASK(dev, type, bits) \
1785 do { \
1786 if (!test_bit(EV_##type, dev->evbit)) \
1787 memset(dev->bits##bit, 0, \
1788 sizeof(dev->bits##bit)); \
1789 } while (0)
1791 static void input_cleanse_bitmasks(struct input_dev *dev)
1793 INPUT_CLEANSE_BITMASK(dev, KEY, key);
1794 INPUT_CLEANSE_BITMASK(dev, REL, rel);
1795 INPUT_CLEANSE_BITMASK(dev, ABS, abs);
1796 INPUT_CLEANSE_BITMASK(dev, MSC, msc);
1797 INPUT_CLEANSE_BITMASK(dev, LED, led);
1798 INPUT_CLEANSE_BITMASK(dev, SND, snd);
1799 INPUT_CLEANSE_BITMASK(dev, FF, ff);
1800 INPUT_CLEANSE_BITMASK(dev, SW, sw);
1804 * input_register_device - register device with input core
1805 * @dev: device to be registered
1807 * This function registers device with input core. The device must be
1808 * allocated with input_allocate_device() and all it's capabilities
1809 * set up before registering.
1810 * If function fails the device must be freed with input_free_device().
1811 * Once device has been successfully registered it can be unregistered
1812 * with input_unregister_device(); input_free_device() should not be
1813 * called in this case.
1815 int input_register_device(struct input_dev *dev)
1817 static atomic_t input_no = ATOMIC_INIT(0);
1818 struct input_handler *handler;
1819 const char *path;
1820 int error;
1822 /* Every input device generates EV_SYN/SYN_REPORT events. */
1823 __set_bit(EV_SYN, dev->evbit);
1825 /* KEY_RESERVED is not supposed to be transmitted to userspace. */
1826 __clear_bit(KEY_RESERVED, dev->keybit);
1828 /* Make sure that bitmasks not mentioned in dev->evbit are clean. */
1829 input_cleanse_bitmasks(dev);
1831 if (!dev->hint_events_per_packet)
1832 dev->hint_events_per_packet =
1833 input_estimate_events_per_packet(dev);
1836 * If delay and period are pre-set by the driver, then autorepeating
1837 * is handled by the driver itself and we don't do it in input.c.
1839 init_timer(&dev->timer);
1840 if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
1841 dev->timer.data = (long) dev;
1842 dev->timer.function = input_repeat_key;
1843 dev->rep[REP_DELAY] = 250;
1844 dev->rep[REP_PERIOD] = 33;
1847 if (!dev->getkeycode)
1848 dev->getkeycode = input_default_getkeycode;
1850 if (!dev->setkeycode)
1851 dev->setkeycode = input_default_setkeycode;
1853 dev_set_name(&dev->dev, "input%ld",
1854 (unsigned long) atomic_inc_return(&input_no) - 1);
1856 error = device_add(&dev->dev);
1857 if (error)
1858 return error;
1860 path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1861 pr_info("%s as %s\n",
1862 dev->name ? dev->name : "Unspecified device",
1863 path ? path : "N/A");
1864 kfree(path);
1866 error = mutex_lock_interruptible(&input_mutex);
1867 if (error) {
1868 device_del(&dev->dev);
1869 return error;
1872 list_add_tail(&dev->node, &input_dev_list);
1874 list_for_each_entry(handler, &input_handler_list, node)
1875 input_attach_handler(dev, handler);
1877 input_wakeup_procfs_readers();
1879 mutex_unlock(&input_mutex);
1881 return 0;
1883 EXPORT_SYMBOL(input_register_device);
1886 * input_unregister_device - unregister previously registered device
1887 * @dev: device to be unregistered
1889 * This function unregisters an input device. Once device is unregistered
1890 * the caller should not try to access it as it may get freed at any moment.
1892 void input_unregister_device(struct input_dev *dev)
1894 struct input_handle *handle, *next;
1896 input_disconnect_device(dev);
1898 mutex_lock(&input_mutex);
1900 list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
1901 handle->handler->disconnect(handle);
1902 WARN_ON(!list_empty(&dev->h_list));
1904 del_timer_sync(&dev->timer);
1905 list_del_init(&dev->node);
1907 input_wakeup_procfs_readers();
1909 mutex_unlock(&input_mutex);
1911 device_unregister(&dev->dev);
1913 EXPORT_SYMBOL(input_unregister_device);
1916 * input_register_handler - register a new input handler
1917 * @handler: handler to be registered
1919 * This function registers a new input handler (interface) for input
1920 * devices in the system and attaches it to all input devices that
1921 * are compatible with the handler.
1923 int input_register_handler(struct input_handler *handler)
1925 struct input_dev *dev;
1926 int retval;
1928 retval = mutex_lock_interruptible(&input_mutex);
1929 if (retval)
1930 return retval;
1932 INIT_LIST_HEAD(&handler->h_list);
1934 if (handler->fops != NULL) {
1935 if (input_table[handler->minor >> 5]) {
1936 retval = -EBUSY;
1937 goto out;
1939 input_table[handler->minor >> 5] = handler;
1942 list_add_tail(&handler->node, &input_handler_list);
1944 list_for_each_entry(dev, &input_dev_list, node)
1945 input_attach_handler(dev, handler);
1947 input_wakeup_procfs_readers();
1949 out:
1950 mutex_unlock(&input_mutex);
1951 return retval;
1953 EXPORT_SYMBOL(input_register_handler);
1956 * input_unregister_handler - unregisters an input handler
1957 * @handler: handler to be unregistered
1959 * This function disconnects a handler from its input devices and
1960 * removes it from lists of known handlers.
1962 void input_unregister_handler(struct input_handler *handler)
1964 struct input_handle *handle, *next;
1966 mutex_lock(&input_mutex);
1968 list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
1969 handler->disconnect(handle);
1970 WARN_ON(!list_empty(&handler->h_list));
1972 list_del_init(&handler->node);
1974 if (handler->fops != NULL)
1975 input_table[handler->minor >> 5] = NULL;
1977 input_wakeup_procfs_readers();
1979 mutex_unlock(&input_mutex);
1981 EXPORT_SYMBOL(input_unregister_handler);
1984 * input_handler_for_each_handle - handle iterator
1985 * @handler: input handler to iterate
1986 * @data: data for the callback
1987 * @fn: function to be called for each handle
1989 * Iterate over @bus's list of devices, and call @fn for each, passing
1990 * it @data and stop when @fn returns a non-zero value. The function is
1991 * using RCU to traverse the list and therefore may be usind in atonic
1992 * contexts. The @fn callback is invoked from RCU critical section and
1993 * thus must not sleep.
1995 int input_handler_for_each_handle(struct input_handler *handler, void *data,
1996 int (*fn)(struct input_handle *, void *))
1998 struct input_handle *handle;
1999 int retval = 0;
2001 rcu_read_lock();
2003 list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
2004 retval = fn(handle, data);
2005 if (retval)
2006 break;
2009 rcu_read_unlock();
2011 return retval;
2013 EXPORT_SYMBOL(input_handler_for_each_handle);
2016 * input_register_handle - register a new input handle
2017 * @handle: handle to register
2019 * This function puts a new input handle onto device's
2020 * and handler's lists so that events can flow through
2021 * it once it is opened using input_open_device().
2023 * This function is supposed to be called from handler's
2024 * connect() method.
2026 int input_register_handle(struct input_handle *handle)
2028 struct input_handler *handler = handle->handler;
2029 struct input_dev *dev = handle->dev;
2030 int error;
2033 * We take dev->mutex here to prevent race with
2034 * input_release_device().
2036 error = mutex_lock_interruptible(&dev->mutex);
2037 if (error)
2038 return error;
2041 * Filters go to the head of the list, normal handlers
2042 * to the tail.
2044 if (handler->filter)
2045 list_add_rcu(&handle->d_node, &dev->h_list);
2046 else
2047 list_add_tail_rcu(&handle->d_node, &dev->h_list);
2049 mutex_unlock(&dev->mutex);
2052 * Since we are supposed to be called from ->connect()
2053 * which is mutually exclusive with ->disconnect()
2054 * we can't be racing with input_unregister_handle()
2055 * and so separate lock is not needed here.
2057 list_add_tail_rcu(&handle->h_node, &handler->h_list);
2059 if (handler->start)
2060 handler->start(handle);
2062 return 0;
2064 EXPORT_SYMBOL(input_register_handle);
2067 * input_unregister_handle - unregister an input handle
2068 * @handle: handle to unregister
2070 * This function removes input handle from device's
2071 * and handler's lists.
2073 * This function is supposed to be called from handler's
2074 * disconnect() method.
2076 void input_unregister_handle(struct input_handle *handle)
2078 struct input_dev *dev = handle->dev;
2080 list_del_rcu(&handle->h_node);
2083 * Take dev->mutex to prevent race with input_release_device().
2085 mutex_lock(&dev->mutex);
2086 list_del_rcu(&handle->d_node);
2087 mutex_unlock(&dev->mutex);
2089 synchronize_rcu();
2091 EXPORT_SYMBOL(input_unregister_handle);
2093 static int input_open_file(struct inode *inode, struct file *file)
2095 struct input_handler *handler;
2096 const struct file_operations *old_fops, *new_fops = NULL;
2097 int err;
2099 err = mutex_lock_interruptible(&input_mutex);
2100 if (err)
2101 return err;
2103 /* No load-on-demand here? */
2104 handler = input_table[iminor(inode) >> 5];
2105 if (handler)
2106 new_fops = fops_get(handler->fops);
2108 mutex_unlock(&input_mutex);
2111 * That's _really_ odd. Usually NULL ->open means "nothing special",
2112 * not "no device". Oh, well...
2114 if (!new_fops || !new_fops->open) {
2115 fops_put(new_fops);
2116 err = -ENODEV;
2117 goto out;
2120 old_fops = file->f_op;
2121 file->f_op = new_fops;
2123 err = new_fops->open(inode, file);
2124 if (err) {
2125 fops_put(file->f_op);
2126 file->f_op = fops_get(old_fops);
2128 fops_put(old_fops);
2129 out:
2130 return err;
2133 static const struct file_operations input_fops = {
2134 .owner = THIS_MODULE,
2135 .open = input_open_file,
2136 .llseek = noop_llseek,
2139 static int __init input_init(void)
2141 int err;
2143 err = class_register(&input_class);
2144 if (err) {
2145 pr_err("unable to register input_dev class\n");
2146 return err;
2149 err = input_proc_init();
2150 if (err)
2151 goto fail1;
2153 err = register_chrdev(INPUT_MAJOR, "input", &input_fops);
2154 if (err) {
2155 pr_err("unable to register char major %d", INPUT_MAJOR);
2156 goto fail2;
2159 return 0;
2161 fail2: input_proc_exit();
2162 fail1: class_unregister(&input_class);
2163 return err;
2166 static void __exit input_exit(void)
2168 input_proc_exit();
2169 unregister_chrdev(INPUT_MAJOR, "input");
2170 class_unregister(&input_class);
2173 subsys_initcall(input_init);
2174 module_exit(input_exit);