4 * Copyright (c) 1999-2002 Vojtech Pavlik
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
46 static DEFINE_MUTEX(input_mutex);
48 static struct input_handler *input_table[8];
50 static const struct input_value input_value_sync = { EV_SYN, SYN_REPORT, 1 };
52 static inline int is_event_supported(unsigned int code,
53 unsigned long *bm, unsigned int max)
55 return code <= max && test_bit(code, bm);
58 static int input_defuzz_abs_event(int value, int old_val, int fuzz)
61 if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
64 if (value > old_val - fuzz && value < old_val + fuzz)
65 return (old_val * 3 + value) / 4;
67 if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
68 return (old_val + value) / 2;
74 static void input_start_autorepeat(struct input_dev *dev, int code)
76 if (test_bit(EV_REP, dev->evbit) &&
77 dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
79 dev->repeat_key = code;
80 mod_timer(&dev->timer,
81 jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
85 static void input_stop_autorepeat(struct input_dev *dev)
87 del_timer(&dev->timer);
91 * Pass event first through all filters and then, if event has not been
92 * filtered out, through all open handles. This function is called with
93 * dev->event_lock held and interrupts disabled.
95 static unsigned int input_to_handler(struct input_handle *handle,
96 struct input_value *vals, unsigned int count)
98 struct input_handler *handler = handle->handler;
99 struct input_value *end = vals;
100 struct input_value *v;
102 for (v = vals; v != vals + count; v++) {
103 if (handler->filter &&
104 handler->filter(handle, v->type, v->code, v->value))
116 handler->events(handle, vals, count);
117 else if (handler->event)
118 for (v = vals; v != end; v++)
119 handler->event(handle, v->type, v->code, v->value);
125 * Pass values first through all filters and then, if event has not been
126 * filtered out, through all open handles. This function is called with
127 * dev->event_lock held and interrupts disabled.
129 static void input_pass_values(struct input_dev *dev,
130 struct input_value *vals, unsigned int count)
132 struct input_handle *handle;
133 struct input_value *v;
140 handle = rcu_dereference(dev->grab);
142 count = input_to_handler(handle, vals, count);
144 list_for_each_entry_rcu(handle, &dev->h_list, d_node)
146 count = input_to_handler(handle, vals, count);
151 add_input_randomness(vals->type, vals->code, vals->value);
153 /* trigger auto repeat for key events */
154 for (v = vals; v != vals + count; v++) {
155 if (v->type == EV_KEY && v->value != 2) {
157 input_start_autorepeat(dev, v->code);
159 input_stop_autorepeat(dev);
164 static void input_pass_event(struct input_dev *dev,
165 unsigned int type, unsigned int code, int value)
167 struct input_value vals[] = { { type, code, value } };
169 input_pass_values(dev, vals, ARRAY_SIZE(vals));
173 * Generate software autorepeat event. Note that we take
174 * dev->event_lock here to avoid racing with input_event
175 * which may cause keys get "stuck".
177 static void input_repeat_key(unsigned long data)
179 struct input_dev *dev = (void *) data;
182 spin_lock_irqsave(&dev->event_lock, flags);
184 if (test_bit(dev->repeat_key, dev->key) &&
185 is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
186 struct input_value vals[] = {
187 { EV_KEY, dev->repeat_key, 2 },
191 input_pass_values(dev, vals, ARRAY_SIZE(vals));
193 if (dev->rep[REP_PERIOD])
194 mod_timer(&dev->timer, jiffies +
195 msecs_to_jiffies(dev->rep[REP_PERIOD]));
198 spin_unlock_irqrestore(&dev->event_lock, flags);
201 #define INPUT_IGNORE_EVENT 0
202 #define INPUT_PASS_TO_HANDLERS 1
203 #define INPUT_PASS_TO_DEVICE 2
205 #define INPUT_FLUSH 8
206 #define INPUT_PASS_TO_ALL (INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
208 static int input_handle_abs_event(struct input_dev *dev,
209 unsigned int code, int *pval)
211 struct input_mt *mt = dev->mt;
215 if (code == ABS_MT_SLOT) {
217 * "Stage" the event; we'll flush it later, when we
218 * get actual touch data.
220 if (mt && *pval >= 0 && *pval < mt->num_slots)
223 return INPUT_IGNORE_EVENT;
226 is_mt_event = input_is_mt_value(code);
229 pold = &dev->absinfo[code].value;
231 pold = &mt->slots[mt->slot].abs[code - ABS_MT_FIRST];
234 * Bypass filtering for multi-touch events when
235 * not employing slots.
241 *pval = input_defuzz_abs_event(*pval, *pold,
242 dev->absinfo[code].fuzz);
244 return INPUT_IGNORE_EVENT;
249 /* Flush pending "slot" event */
250 if (is_mt_event && mt && mt->slot != input_abs_get_val(dev, ABS_MT_SLOT)) {
251 input_abs_set_val(dev, ABS_MT_SLOT, mt->slot);
252 return INPUT_PASS_TO_HANDLERS | INPUT_SLOT;
255 return INPUT_PASS_TO_HANDLERS;
258 static int input_get_disposition(struct input_dev *dev,
259 unsigned int type, unsigned int code, int value)
261 int disposition = INPUT_IGNORE_EVENT;
268 disposition = INPUT_PASS_TO_ALL;
272 disposition = INPUT_PASS_TO_HANDLERS | INPUT_FLUSH;
275 disposition = INPUT_PASS_TO_HANDLERS;
281 if (is_event_supported(code, dev->keybit, KEY_MAX)) {
283 /* auto-repeat bypasses state updates */
285 disposition = INPUT_PASS_TO_HANDLERS;
289 if (!!test_bit(code, dev->key) != !!value) {
291 __change_bit(code, dev->key);
292 disposition = INPUT_PASS_TO_HANDLERS;
298 if (is_event_supported(code, dev->swbit, SW_MAX) &&
299 !!test_bit(code, dev->sw) != !!value) {
301 __change_bit(code, dev->sw);
302 disposition = INPUT_PASS_TO_HANDLERS;
307 if (is_event_supported(code, dev->absbit, ABS_MAX))
308 disposition = input_handle_abs_event(dev, code, &value);
313 if (is_event_supported(code, dev->relbit, REL_MAX) && value)
314 disposition = INPUT_PASS_TO_HANDLERS;
319 if (is_event_supported(code, dev->mscbit, MSC_MAX))
320 disposition = INPUT_PASS_TO_ALL;
325 if (is_event_supported(code, dev->ledbit, LED_MAX) &&
326 !!test_bit(code, dev->led) != !!value) {
328 __change_bit(code, dev->led);
329 disposition = INPUT_PASS_TO_ALL;
334 if (is_event_supported(code, dev->sndbit, SND_MAX)) {
336 if (!!test_bit(code, dev->snd) != !!value)
337 __change_bit(code, dev->snd);
338 disposition = INPUT_PASS_TO_ALL;
343 if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
344 dev->rep[code] = value;
345 disposition = INPUT_PASS_TO_ALL;
351 disposition = INPUT_PASS_TO_ALL;
355 disposition = INPUT_PASS_TO_ALL;
362 static void input_handle_event(struct input_dev *dev,
363 unsigned int type, unsigned int code, int value)
367 disposition = input_get_disposition(dev, type, code, value);
369 if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
370 dev->event(dev, type, code, value);
375 if (disposition & INPUT_PASS_TO_HANDLERS) {
376 struct input_value *v;
378 if (disposition & INPUT_SLOT) {
379 v = &dev->vals[dev->num_vals++];
381 v->code = ABS_MT_SLOT;
382 v->value = dev->mt->slot;
385 v = &dev->vals[dev->num_vals++];
391 if (disposition & INPUT_FLUSH) {
392 if (dev->num_vals >= 2)
393 input_pass_values(dev, dev->vals, dev->num_vals);
395 } else if (dev->num_vals >= dev->max_vals - 2) {
396 dev->vals[dev->num_vals++] = input_value_sync;
397 input_pass_values(dev, dev->vals, dev->num_vals);
404 * input_event() - report new input event
405 * @dev: device that generated the event
406 * @type: type of the event
408 * @value: value of the event
410 * This function should be used by drivers implementing various input
411 * devices to report input events. See also input_inject_event().
413 * NOTE: input_event() may be safely used right after input device was
414 * allocated with input_allocate_device(), even before it is registered
415 * with input_register_device(), but the event will not reach any of the
416 * input handlers. Such early invocation of input_event() may be used
417 * to 'seed' initial state of a switch or initial position of absolute
420 void input_event(struct input_dev *dev,
421 unsigned int type, unsigned int code, int value)
425 if (is_event_supported(type, dev->evbit, EV_MAX)) {
427 spin_lock_irqsave(&dev->event_lock, flags);
428 input_handle_event(dev, type, code, value);
429 spin_unlock_irqrestore(&dev->event_lock, flags);
432 EXPORT_SYMBOL(input_event);
435 * input_inject_event() - send input event from input handler
436 * @handle: input handle to send event through
437 * @type: type of the event
439 * @value: value of the event
441 * Similar to input_event() but will ignore event if device is
442 * "grabbed" and handle injecting event is not the one that owns
445 void input_inject_event(struct input_handle *handle,
446 unsigned int type, unsigned int code, int value)
448 struct input_dev *dev = handle->dev;
449 struct input_handle *grab;
452 if (is_event_supported(type, dev->evbit, EV_MAX)) {
453 spin_lock_irqsave(&dev->event_lock, flags);
456 grab = rcu_dereference(dev->grab);
457 if (!grab || grab == handle)
458 input_handle_event(dev, type, code, value);
461 spin_unlock_irqrestore(&dev->event_lock, flags);
464 EXPORT_SYMBOL(input_inject_event);
467 * input_alloc_absinfo - allocates array of input_absinfo structs
468 * @dev: the input device emitting absolute events
470 * If the absinfo struct the caller asked for is already allocated, this
471 * functions will not do anything.
473 void input_alloc_absinfo(struct input_dev *dev)
476 dev->absinfo = kcalloc(ABS_CNT, sizeof(struct input_absinfo),
479 WARN(!dev->absinfo, "%s(): kcalloc() failed?\n", __func__);
481 EXPORT_SYMBOL(input_alloc_absinfo);
483 void input_set_abs_params(struct input_dev *dev, unsigned int axis,
484 int min, int max, int fuzz, int flat)
486 struct input_absinfo *absinfo;
488 input_alloc_absinfo(dev);
492 absinfo = &dev->absinfo[axis];
493 absinfo->minimum = min;
494 absinfo->maximum = max;
495 absinfo->fuzz = fuzz;
496 absinfo->flat = flat;
498 dev->absbit[BIT_WORD(axis)] |= BIT_MASK(axis);
500 EXPORT_SYMBOL(input_set_abs_params);
504 * input_grab_device - grabs device for exclusive use
505 * @handle: input handle that wants to own the device
507 * When a device is grabbed by an input handle all events generated by
508 * the device are delivered only to this handle. Also events injected
509 * by other input handles are ignored while device is grabbed.
511 int input_grab_device(struct input_handle *handle)
513 struct input_dev *dev = handle->dev;
516 retval = mutex_lock_interruptible(&dev->mutex);
525 rcu_assign_pointer(dev->grab, handle);
528 mutex_unlock(&dev->mutex);
531 EXPORT_SYMBOL(input_grab_device);
533 static void __input_release_device(struct input_handle *handle)
535 struct input_dev *dev = handle->dev;
537 if (dev->grab == handle) {
538 rcu_assign_pointer(dev->grab, NULL);
539 /* Make sure input_pass_event() notices that grab is gone */
542 list_for_each_entry(handle, &dev->h_list, d_node)
543 if (handle->open && handle->handler->start)
544 handle->handler->start(handle);
549 * input_release_device - release previously grabbed device
550 * @handle: input handle that owns the device
552 * Releases previously grabbed device so that other input handles can
553 * start receiving input events. Upon release all handlers attached
554 * to the device have their start() method called so they have a change
555 * to synchronize device state with the rest of the system.
557 void input_release_device(struct input_handle *handle)
559 struct input_dev *dev = handle->dev;
561 mutex_lock(&dev->mutex);
562 __input_release_device(handle);
563 mutex_unlock(&dev->mutex);
565 EXPORT_SYMBOL(input_release_device);
568 * input_open_device - open input device
569 * @handle: handle through which device is being accessed
571 * This function should be called by input handlers when they
572 * want to start receive events from given input device.
574 int input_open_device(struct input_handle *handle)
576 struct input_dev *dev = handle->dev;
579 retval = mutex_lock_interruptible(&dev->mutex);
583 if (dev->going_away) {
590 if (!dev->users++ && dev->open)
591 retval = dev->open(dev);
595 if (!--handle->open) {
597 * Make sure we are not delivering any more events
598 * through this handle
605 mutex_unlock(&dev->mutex);
608 EXPORT_SYMBOL(input_open_device);
610 int input_flush_device(struct input_handle *handle, struct file *file)
612 struct input_dev *dev = handle->dev;
615 retval = mutex_lock_interruptible(&dev->mutex);
620 retval = dev->flush(dev, file);
622 mutex_unlock(&dev->mutex);
625 EXPORT_SYMBOL(input_flush_device);
628 * input_close_device - close input device
629 * @handle: handle through which device is being accessed
631 * This function should be called by input handlers when they
632 * want to stop receive events from given input device.
634 void input_close_device(struct input_handle *handle)
636 struct input_dev *dev = handle->dev;
638 mutex_lock(&dev->mutex);
640 __input_release_device(handle);
642 if (!--dev->users && dev->close)
645 if (!--handle->open) {
647 * synchronize_rcu() makes sure that input_pass_event()
648 * completed and that no more input events are delivered
649 * through this handle
654 mutex_unlock(&dev->mutex);
656 EXPORT_SYMBOL(input_close_device);
659 * Simulate keyup events for all keys that are marked as pressed.
660 * The function must be called with dev->event_lock held.
662 static void input_dev_release_keys(struct input_dev *dev)
666 if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
667 for (code = 0; code <= KEY_MAX; code++) {
668 if (is_event_supported(code, dev->keybit, KEY_MAX) &&
669 __test_and_clear_bit(code, dev->key)) {
670 input_pass_event(dev, EV_KEY, code, 0);
673 input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
678 * Prepare device for unregistering
680 static void input_disconnect_device(struct input_dev *dev)
682 struct input_handle *handle;
685 * Mark device as going away. Note that we take dev->mutex here
686 * not to protect access to dev->going_away but rather to ensure
687 * that there are no threads in the middle of input_open_device()
689 mutex_lock(&dev->mutex);
690 dev->going_away = true;
691 mutex_unlock(&dev->mutex);
693 spin_lock_irq(&dev->event_lock);
696 * Simulate keyup events for all pressed keys so that handlers
697 * are not left with "stuck" keys. The driver may continue
698 * generate events even after we done here but they will not
699 * reach any handlers.
701 input_dev_release_keys(dev);
703 list_for_each_entry(handle, &dev->h_list, d_node)
706 spin_unlock_irq(&dev->event_lock);
710 * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
711 * @ke: keymap entry containing scancode to be converted.
712 * @scancode: pointer to the location where converted scancode should
715 * This function is used to convert scancode stored in &struct keymap_entry
716 * into scalar form understood by legacy keymap handling methods. These
717 * methods expect scancodes to be represented as 'unsigned int'.
719 int input_scancode_to_scalar(const struct input_keymap_entry *ke,
720 unsigned int *scancode)
724 *scancode = *((u8 *)ke->scancode);
728 *scancode = *((u16 *)ke->scancode);
732 *scancode = *((u32 *)ke->scancode);
741 EXPORT_SYMBOL(input_scancode_to_scalar);
744 * Those routines handle the default case where no [gs]etkeycode() is
745 * defined. In this case, an array indexed by the scancode is used.
748 static unsigned int input_fetch_keycode(struct input_dev *dev,
751 switch (dev->keycodesize) {
753 return ((u8 *)dev->keycode)[index];
756 return ((u16 *)dev->keycode)[index];
759 return ((u32 *)dev->keycode)[index];
763 static int input_default_getkeycode(struct input_dev *dev,
764 struct input_keymap_entry *ke)
769 if (!dev->keycodesize)
772 if (ke->flags & INPUT_KEYMAP_BY_INDEX)
775 error = input_scancode_to_scalar(ke, &index);
780 if (index >= dev->keycodemax)
783 ke->keycode = input_fetch_keycode(dev, index);
785 ke->len = sizeof(index);
786 memcpy(ke->scancode, &index, sizeof(index));
791 static int input_default_setkeycode(struct input_dev *dev,
792 const struct input_keymap_entry *ke,
793 unsigned int *old_keycode)
799 if (!dev->keycodesize)
802 if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
805 error = input_scancode_to_scalar(ke, &index);
810 if (index >= dev->keycodemax)
813 if (dev->keycodesize < sizeof(ke->keycode) &&
814 (ke->keycode >> (dev->keycodesize * 8)))
817 switch (dev->keycodesize) {
819 u8 *k = (u8 *)dev->keycode;
820 *old_keycode = k[index];
821 k[index] = ke->keycode;
825 u16 *k = (u16 *)dev->keycode;
826 *old_keycode = k[index];
827 k[index] = ke->keycode;
831 u32 *k = (u32 *)dev->keycode;
832 *old_keycode = k[index];
833 k[index] = ke->keycode;
838 __clear_bit(*old_keycode, dev->keybit);
839 __set_bit(ke->keycode, dev->keybit);
841 for (i = 0; i < dev->keycodemax; i++) {
842 if (input_fetch_keycode(dev, i) == *old_keycode) {
843 __set_bit(*old_keycode, dev->keybit);
844 break; /* Setting the bit twice is useless, so break */
852 * input_get_keycode - retrieve keycode currently mapped to a given scancode
853 * @dev: input device which keymap is being queried
856 * This function should be called by anyone interested in retrieving current
857 * keymap. Presently evdev handlers use it.
859 int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
864 spin_lock_irqsave(&dev->event_lock, flags);
865 retval = dev->getkeycode(dev, ke);
866 spin_unlock_irqrestore(&dev->event_lock, flags);
870 EXPORT_SYMBOL(input_get_keycode);
873 * input_set_keycode - attribute a keycode to a given scancode
874 * @dev: input device which keymap is being updated
875 * @ke: new keymap entry
877 * This function should be called by anyone needing to update current
878 * keymap. Presently keyboard and evdev handlers use it.
880 int input_set_keycode(struct input_dev *dev,
881 const struct input_keymap_entry *ke)
884 unsigned int old_keycode;
887 if (ke->keycode > KEY_MAX)
890 spin_lock_irqsave(&dev->event_lock, flags);
892 retval = dev->setkeycode(dev, ke, &old_keycode);
896 /* Make sure KEY_RESERVED did not get enabled. */
897 __clear_bit(KEY_RESERVED, dev->keybit);
900 * Simulate keyup event if keycode is not present
901 * in the keymap anymore
903 if (test_bit(EV_KEY, dev->evbit) &&
904 !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
905 __test_and_clear_bit(old_keycode, dev->key)) {
906 struct input_value vals[] = {
907 { EV_KEY, old_keycode, 0 },
911 input_pass_values(dev, vals, ARRAY_SIZE(vals));
915 spin_unlock_irqrestore(&dev->event_lock, flags);
919 EXPORT_SYMBOL(input_set_keycode);
921 #define MATCH_BIT(bit, max) \
922 for (i = 0; i < BITS_TO_LONGS(max); i++) \
923 if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \
925 if (i != BITS_TO_LONGS(max)) \
928 static const struct input_device_id *input_match_device(struct input_handler *handler,
929 struct input_dev *dev)
931 const struct input_device_id *id;
934 for (id = handler->id_table; id->flags || id->driver_info; id++) {
936 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
937 if (id->bustype != dev->id.bustype)
940 if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
941 if (id->vendor != dev->id.vendor)
944 if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
945 if (id->product != dev->id.product)
948 if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
949 if (id->version != dev->id.version)
952 MATCH_BIT(evbit, EV_MAX);
953 MATCH_BIT(keybit, KEY_MAX);
954 MATCH_BIT(relbit, REL_MAX);
955 MATCH_BIT(absbit, ABS_MAX);
956 MATCH_BIT(mscbit, MSC_MAX);
957 MATCH_BIT(ledbit, LED_MAX);
958 MATCH_BIT(sndbit, SND_MAX);
959 MATCH_BIT(ffbit, FF_MAX);
960 MATCH_BIT(swbit, SW_MAX);
962 if (!handler->match || handler->match(handler, dev))
969 static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
971 const struct input_device_id *id;
974 id = input_match_device(handler, dev);
978 error = handler->connect(handler, dev, id);
979 if (error && error != -ENODEV)
980 pr_err("failed to attach handler %s to device %s, error: %d\n",
981 handler->name, kobject_name(&dev->dev.kobj), error);
988 static int input_bits_to_string(char *buf, int buf_size,
989 unsigned long bits, bool skip_empty)
993 if (INPUT_COMPAT_TEST) {
994 u32 dword = bits >> 32;
995 if (dword || !skip_empty)
996 len += snprintf(buf, buf_size, "%x ", dword);
998 dword = bits & 0xffffffffUL;
999 if (dword || !skip_empty || len)
1000 len += snprintf(buf + len, max(buf_size - len, 0),
1003 if (bits || !skip_empty)
1004 len += snprintf(buf, buf_size, "%lx", bits);
1010 #else /* !CONFIG_COMPAT */
1012 static int input_bits_to_string(char *buf, int buf_size,
1013 unsigned long bits, bool skip_empty)
1015 return bits || !skip_empty ?
1016 snprintf(buf, buf_size, "%lx", bits) : 0;
1021 #ifdef CONFIG_PROC_FS
1023 static struct proc_dir_entry *proc_bus_input_dir;
1024 static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
1025 static int input_devices_state;
1027 static inline void input_wakeup_procfs_readers(void)
1029 input_devices_state++;
1030 wake_up(&input_devices_poll_wait);
1033 static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
1035 poll_wait(file, &input_devices_poll_wait, wait);
1036 if (file->f_version != input_devices_state) {
1037 file->f_version = input_devices_state;
1038 return POLLIN | POLLRDNORM;
1044 union input_seq_state {
1047 bool mutex_acquired;
1052 static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
1054 union input_seq_state *state = (union input_seq_state *)&seq->private;
1057 /* We need to fit into seq->private pointer */
1058 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1060 error = mutex_lock_interruptible(&input_mutex);
1062 state->mutex_acquired = false;
1063 return ERR_PTR(error);
1066 state->mutex_acquired = true;
1068 return seq_list_start(&input_dev_list, *pos);
1071 static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1073 return seq_list_next(v, &input_dev_list, pos);
1076 static void input_seq_stop(struct seq_file *seq, void *v)
1078 union input_seq_state *state = (union input_seq_state *)&seq->private;
1080 if (state->mutex_acquired)
1081 mutex_unlock(&input_mutex);
1084 static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
1085 unsigned long *bitmap, int max)
1088 bool skip_empty = true;
1091 seq_printf(seq, "B: %s=", name);
1093 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1094 if (input_bits_to_string(buf, sizeof(buf),
1095 bitmap[i], skip_empty)) {
1097 seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
1102 * If no output was produced print a single 0.
1107 seq_putc(seq, '\n');
1110 static int input_devices_seq_show(struct seq_file *seq, void *v)
1112 struct input_dev *dev = container_of(v, struct input_dev, node);
1113 const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1114 struct input_handle *handle;
1116 seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
1117 dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
1119 seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
1120 seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
1121 seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
1122 seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1123 seq_printf(seq, "H: Handlers=");
1125 list_for_each_entry(handle, &dev->h_list, d_node)
1126 seq_printf(seq, "%s ", handle->name);
1127 seq_putc(seq, '\n');
1129 input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
1131 input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
1132 if (test_bit(EV_KEY, dev->evbit))
1133 input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
1134 if (test_bit(EV_REL, dev->evbit))
1135 input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
1136 if (test_bit(EV_ABS, dev->evbit))
1137 input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
1138 if (test_bit(EV_MSC, dev->evbit))
1139 input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
1140 if (test_bit(EV_LED, dev->evbit))
1141 input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
1142 if (test_bit(EV_SND, dev->evbit))
1143 input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
1144 if (test_bit(EV_FF, dev->evbit))
1145 input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
1146 if (test_bit(EV_SW, dev->evbit))
1147 input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
1149 seq_putc(seq, '\n');
1155 static const struct seq_operations input_devices_seq_ops = {
1156 .start = input_devices_seq_start,
1157 .next = input_devices_seq_next,
1158 .stop = input_seq_stop,
1159 .show = input_devices_seq_show,
1162 static int input_proc_devices_open(struct inode *inode, struct file *file)
1164 return seq_open(file, &input_devices_seq_ops);
1167 static const struct file_operations input_devices_fileops = {
1168 .owner = THIS_MODULE,
1169 .open = input_proc_devices_open,
1170 .poll = input_proc_devices_poll,
1172 .llseek = seq_lseek,
1173 .release = seq_release,
1176 static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
1178 union input_seq_state *state = (union input_seq_state *)&seq->private;
1181 /* We need to fit into seq->private pointer */
1182 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1184 error = mutex_lock_interruptible(&input_mutex);
1186 state->mutex_acquired = false;
1187 return ERR_PTR(error);
1190 state->mutex_acquired = true;
1193 return seq_list_start(&input_handler_list, *pos);
1196 static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1198 union input_seq_state *state = (union input_seq_state *)&seq->private;
1200 state->pos = *pos + 1;
1201 return seq_list_next(v, &input_handler_list, pos);
1204 static int input_handlers_seq_show(struct seq_file *seq, void *v)
1206 struct input_handler *handler = container_of(v, struct input_handler, node);
1207 union input_seq_state *state = (union input_seq_state *)&seq->private;
1209 seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
1210 if (handler->filter)
1211 seq_puts(seq, " (filter)");
1213 seq_printf(seq, " Minor=%d", handler->minor);
1214 seq_putc(seq, '\n');
1219 static const struct seq_operations input_handlers_seq_ops = {
1220 .start = input_handlers_seq_start,
1221 .next = input_handlers_seq_next,
1222 .stop = input_seq_stop,
1223 .show = input_handlers_seq_show,
1226 static int input_proc_handlers_open(struct inode *inode, struct file *file)
1228 return seq_open(file, &input_handlers_seq_ops);
1231 static const struct file_operations input_handlers_fileops = {
1232 .owner = THIS_MODULE,
1233 .open = input_proc_handlers_open,
1235 .llseek = seq_lseek,
1236 .release = seq_release,
1239 static int __init input_proc_init(void)
1241 struct proc_dir_entry *entry;
1243 proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1244 if (!proc_bus_input_dir)
1247 entry = proc_create("devices", 0, proc_bus_input_dir,
1248 &input_devices_fileops);
1252 entry = proc_create("handlers", 0, proc_bus_input_dir,
1253 &input_handlers_fileops);
1259 fail2: remove_proc_entry("devices", proc_bus_input_dir);
1260 fail1: remove_proc_entry("bus/input", NULL);
1264 static void input_proc_exit(void)
1266 remove_proc_entry("devices", proc_bus_input_dir);
1267 remove_proc_entry("handlers", proc_bus_input_dir);
1268 remove_proc_entry("bus/input", NULL);
1271 #else /* !CONFIG_PROC_FS */
1272 static inline void input_wakeup_procfs_readers(void) { }
1273 static inline int input_proc_init(void) { return 0; }
1274 static inline void input_proc_exit(void) { }
1277 #define INPUT_DEV_STRING_ATTR_SHOW(name) \
1278 static ssize_t input_dev_show_##name(struct device *dev, \
1279 struct device_attribute *attr, \
1282 struct input_dev *input_dev = to_input_dev(dev); \
1284 return scnprintf(buf, PAGE_SIZE, "%s\n", \
1285 input_dev->name ? input_dev->name : ""); \
1287 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1289 INPUT_DEV_STRING_ATTR_SHOW(name);
1290 INPUT_DEV_STRING_ATTR_SHOW(phys);
1291 INPUT_DEV_STRING_ATTR_SHOW(uniq);
1293 static int input_print_modalias_bits(char *buf, int size,
1294 char name, unsigned long *bm,
1295 unsigned int min_bit, unsigned int max_bit)
1299 len += snprintf(buf, max(size, 0), "%c", name);
1300 for (i = min_bit; i < max_bit; i++)
1301 if (bm[BIT_WORD(i)] & BIT_MASK(i))
1302 len += snprintf(buf + len, max(size - len, 0), "%X,", i);
1306 static int input_print_modalias(char *buf, int size, struct input_dev *id,
1311 len = snprintf(buf, max(size, 0),
1312 "input:b%04Xv%04Xp%04Xe%04X-",
1313 id->id.bustype, id->id.vendor,
1314 id->id.product, id->id.version);
1316 len += input_print_modalias_bits(buf + len, size - len,
1317 'e', id->evbit, 0, EV_MAX);
1318 len += input_print_modalias_bits(buf + len, size - len,
1319 'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1320 len += input_print_modalias_bits(buf + len, size - len,
1321 'r', id->relbit, 0, REL_MAX);
1322 len += input_print_modalias_bits(buf + len, size - len,
1323 'a', id->absbit, 0, ABS_MAX);
1324 len += input_print_modalias_bits(buf + len, size - len,
1325 'm', id->mscbit, 0, MSC_MAX);
1326 len += input_print_modalias_bits(buf + len, size - len,
1327 'l', id->ledbit, 0, LED_MAX);
1328 len += input_print_modalias_bits(buf + len, size - len,
1329 's', id->sndbit, 0, SND_MAX);
1330 len += input_print_modalias_bits(buf + len, size - len,
1331 'f', id->ffbit, 0, FF_MAX);
1332 len += input_print_modalias_bits(buf + len, size - len,
1333 'w', id->swbit, 0, SW_MAX);
1336 len += snprintf(buf + len, max(size - len, 0), "\n");
1341 static ssize_t input_dev_show_modalias(struct device *dev,
1342 struct device_attribute *attr,
1345 struct input_dev *id = to_input_dev(dev);
1348 len = input_print_modalias(buf, PAGE_SIZE, id, 1);
1350 return min_t(int, len, PAGE_SIZE);
1352 static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1354 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1355 int max, int add_cr);
1357 static ssize_t input_dev_show_properties(struct device *dev,
1358 struct device_attribute *attr,
1361 struct input_dev *input_dev = to_input_dev(dev);
1362 int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
1363 INPUT_PROP_MAX, true);
1364 return min_t(int, len, PAGE_SIZE);
1366 static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
1368 static struct attribute *input_dev_attrs[] = {
1369 &dev_attr_name.attr,
1370 &dev_attr_phys.attr,
1371 &dev_attr_uniq.attr,
1372 &dev_attr_modalias.attr,
1373 &dev_attr_properties.attr,
1377 static struct attribute_group input_dev_attr_group = {
1378 .attrs = input_dev_attrs,
1381 #define INPUT_DEV_ID_ATTR(name) \
1382 static ssize_t input_dev_show_id_##name(struct device *dev, \
1383 struct device_attribute *attr, \
1386 struct input_dev *input_dev = to_input_dev(dev); \
1387 return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name); \
1389 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1391 INPUT_DEV_ID_ATTR(bustype);
1392 INPUT_DEV_ID_ATTR(vendor);
1393 INPUT_DEV_ID_ATTR(product);
1394 INPUT_DEV_ID_ATTR(version);
1396 static struct attribute *input_dev_id_attrs[] = {
1397 &dev_attr_bustype.attr,
1398 &dev_attr_vendor.attr,
1399 &dev_attr_product.attr,
1400 &dev_attr_version.attr,
1404 static struct attribute_group input_dev_id_attr_group = {
1406 .attrs = input_dev_id_attrs,
1409 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1410 int max, int add_cr)
1414 bool skip_empty = true;
1416 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1417 len += input_bits_to_string(buf + len, max(buf_size - len, 0),
1418 bitmap[i], skip_empty);
1422 len += snprintf(buf + len, max(buf_size - len, 0), " ");
1427 * If no output was produced print a single 0.
1430 len = snprintf(buf, buf_size, "%d", 0);
1433 len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1438 #define INPUT_DEV_CAP_ATTR(ev, bm) \
1439 static ssize_t input_dev_show_cap_##bm(struct device *dev, \
1440 struct device_attribute *attr, \
1443 struct input_dev *input_dev = to_input_dev(dev); \
1444 int len = input_print_bitmap(buf, PAGE_SIZE, \
1445 input_dev->bm##bit, ev##_MAX, \
1447 return min_t(int, len, PAGE_SIZE); \
1449 static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1451 INPUT_DEV_CAP_ATTR(EV, ev);
1452 INPUT_DEV_CAP_ATTR(KEY, key);
1453 INPUT_DEV_CAP_ATTR(REL, rel);
1454 INPUT_DEV_CAP_ATTR(ABS, abs);
1455 INPUT_DEV_CAP_ATTR(MSC, msc);
1456 INPUT_DEV_CAP_ATTR(LED, led);
1457 INPUT_DEV_CAP_ATTR(SND, snd);
1458 INPUT_DEV_CAP_ATTR(FF, ff);
1459 INPUT_DEV_CAP_ATTR(SW, sw);
1461 static struct attribute *input_dev_caps_attrs[] = {
1474 static struct attribute_group input_dev_caps_attr_group = {
1475 .name = "capabilities",
1476 .attrs = input_dev_caps_attrs,
1479 static const struct attribute_group *input_dev_attr_groups[] = {
1480 &input_dev_attr_group,
1481 &input_dev_id_attr_group,
1482 &input_dev_caps_attr_group,
1486 static void input_dev_release(struct device *device)
1488 struct input_dev *dev = to_input_dev(device);
1490 input_ff_destroy(dev);
1491 input_mt_destroy_slots(dev);
1492 kfree(dev->absinfo);
1496 module_put(THIS_MODULE);
1500 * Input uevent interface - loading event handlers based on
1503 static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1504 const char *name, unsigned long *bitmap, int max)
1508 if (add_uevent_var(env, "%s", name))
1511 len = input_print_bitmap(&env->buf[env->buflen - 1],
1512 sizeof(env->buf) - env->buflen,
1513 bitmap, max, false);
1514 if (len >= (sizeof(env->buf) - env->buflen))
1521 static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1522 struct input_dev *dev)
1526 if (add_uevent_var(env, "MODALIAS="))
1529 len = input_print_modalias(&env->buf[env->buflen - 1],
1530 sizeof(env->buf) - env->buflen,
1532 if (len >= (sizeof(env->buf) - env->buflen))
1539 #define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \
1541 int err = add_uevent_var(env, fmt, val); \
1546 #define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max) \
1548 int err = input_add_uevent_bm_var(env, name, bm, max); \
1553 #define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \
1555 int err = input_add_uevent_modalias_var(env, dev); \
1560 static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
1562 struct input_dev *dev = to_input_dev(device);
1564 INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1565 dev->id.bustype, dev->id.vendor,
1566 dev->id.product, dev->id.version);
1568 INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1570 INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1572 INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1574 INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
1576 INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1577 if (test_bit(EV_KEY, dev->evbit))
1578 INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1579 if (test_bit(EV_REL, dev->evbit))
1580 INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1581 if (test_bit(EV_ABS, dev->evbit))
1582 INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1583 if (test_bit(EV_MSC, dev->evbit))
1584 INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1585 if (test_bit(EV_LED, dev->evbit))
1586 INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1587 if (test_bit(EV_SND, dev->evbit))
1588 INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1589 if (test_bit(EV_FF, dev->evbit))
1590 INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1591 if (test_bit(EV_SW, dev->evbit))
1592 INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1594 INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1599 #define INPUT_DO_TOGGLE(dev, type, bits, on) \
1604 if (!test_bit(EV_##type, dev->evbit)) \
1607 for (i = 0; i < type##_MAX; i++) { \
1608 if (!test_bit(i, dev->bits##bit)) \
1611 active = test_bit(i, dev->bits); \
1612 if (!active && !on) \
1615 dev->event(dev, EV_##type, i, on ? active : 0); \
1619 static void input_dev_toggle(struct input_dev *dev, bool activate)
1624 INPUT_DO_TOGGLE(dev, LED, led, activate);
1625 INPUT_DO_TOGGLE(dev, SND, snd, activate);
1627 if (activate && test_bit(EV_REP, dev->evbit)) {
1628 dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1629 dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1634 * input_reset_device() - reset/restore the state of input device
1635 * @dev: input device whose state needs to be reset
1637 * This function tries to reset the state of an opened input device and
1638 * bring internal state and state if the hardware in sync with each other.
1639 * We mark all keys as released, restore LED state, repeat rate, etc.
1641 void input_reset_device(struct input_dev *dev)
1643 mutex_lock(&dev->mutex);
1646 input_dev_toggle(dev, true);
1649 * Keys that have been pressed at suspend time are unlikely
1650 * to be still pressed when we resume.
1652 spin_lock_irq(&dev->event_lock);
1653 input_dev_release_keys(dev);
1654 spin_unlock_irq(&dev->event_lock);
1657 mutex_unlock(&dev->mutex);
1659 EXPORT_SYMBOL(input_reset_device);
1662 static int input_dev_suspend(struct device *dev)
1664 struct input_dev *input_dev = to_input_dev(dev);
1666 mutex_lock(&input_dev->mutex);
1668 if (input_dev->users)
1669 input_dev_toggle(input_dev, false);
1671 mutex_unlock(&input_dev->mutex);
1676 static int input_dev_resume(struct device *dev)
1678 struct input_dev *input_dev = to_input_dev(dev);
1680 input_reset_device(input_dev);
1685 static const struct dev_pm_ops input_dev_pm_ops = {
1686 .suspend = input_dev_suspend,
1687 .resume = input_dev_resume,
1688 .poweroff = input_dev_suspend,
1689 .restore = input_dev_resume,
1691 #endif /* CONFIG_PM */
1693 static struct device_type input_dev_type = {
1694 .groups = input_dev_attr_groups,
1695 .release = input_dev_release,
1696 .uevent = input_dev_uevent,
1698 .pm = &input_dev_pm_ops,
1702 static char *input_devnode(struct device *dev, umode_t *mode)
1704 return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
1707 struct class input_class = {
1709 .devnode = input_devnode,
1711 EXPORT_SYMBOL_GPL(input_class);
1714 * input_allocate_device - allocate memory for new input device
1716 * Returns prepared struct input_dev or NULL.
1718 * NOTE: Use input_free_device() to free devices that have not been
1719 * registered; input_unregister_device() should be used for already
1720 * registered devices.
1722 struct input_dev *input_allocate_device(void)
1724 struct input_dev *dev;
1726 dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
1728 dev->dev.type = &input_dev_type;
1729 dev->dev.class = &input_class;
1730 device_initialize(&dev->dev);
1731 mutex_init(&dev->mutex);
1732 spin_lock_init(&dev->event_lock);
1733 INIT_LIST_HEAD(&dev->h_list);
1734 INIT_LIST_HEAD(&dev->node);
1736 __module_get(THIS_MODULE);
1741 EXPORT_SYMBOL(input_allocate_device);
1744 * input_free_device - free memory occupied by input_dev structure
1745 * @dev: input device to free
1747 * This function should only be used if input_register_device()
1748 * was not called yet or if it failed. Once device was registered
1749 * use input_unregister_device() and memory will be freed once last
1750 * reference to the device is dropped.
1752 * Device should be allocated by input_allocate_device().
1754 * NOTE: If there are references to the input device then memory
1755 * will not be freed until last reference is dropped.
1757 void input_free_device(struct input_dev *dev)
1760 input_put_device(dev);
1762 EXPORT_SYMBOL(input_free_device);
1765 * input_set_capability - mark device as capable of a certain event
1766 * @dev: device that is capable of emitting or accepting event
1767 * @type: type of the event (EV_KEY, EV_REL, etc...)
1770 * In addition to setting up corresponding bit in appropriate capability
1771 * bitmap the function also adjusts dev->evbit.
1773 void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
1777 __set_bit(code, dev->keybit);
1781 __set_bit(code, dev->relbit);
1785 __set_bit(code, dev->absbit);
1789 __set_bit(code, dev->mscbit);
1793 __set_bit(code, dev->swbit);
1797 __set_bit(code, dev->ledbit);
1801 __set_bit(code, dev->sndbit);
1805 __set_bit(code, dev->ffbit);
1813 pr_err("input_set_capability: unknown type %u (code %u)\n",
1819 __set_bit(type, dev->evbit);
1821 EXPORT_SYMBOL(input_set_capability);
1823 static unsigned int input_estimate_events_per_packet(struct input_dev *dev)
1827 unsigned int events;
1830 mt_slots = dev->mt->num_slots;
1831 } else if (test_bit(ABS_MT_TRACKING_ID, dev->absbit)) {
1832 mt_slots = dev->absinfo[ABS_MT_TRACKING_ID].maximum -
1833 dev->absinfo[ABS_MT_TRACKING_ID].minimum + 1,
1834 mt_slots = clamp(mt_slots, 2, 32);
1835 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
1841 events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */
1843 for (i = 0; i < ABS_CNT; i++) {
1844 if (test_bit(i, dev->absbit)) {
1845 if (input_is_mt_axis(i))
1852 for (i = 0; i < REL_CNT; i++)
1853 if (test_bit(i, dev->relbit))
1856 /* Make room for KEY and MSC events */
1862 #define INPUT_CLEANSE_BITMASK(dev, type, bits) \
1864 if (!test_bit(EV_##type, dev->evbit)) \
1865 memset(dev->bits##bit, 0, \
1866 sizeof(dev->bits##bit)); \
1869 static void input_cleanse_bitmasks(struct input_dev *dev)
1871 INPUT_CLEANSE_BITMASK(dev, KEY, key);
1872 INPUT_CLEANSE_BITMASK(dev, REL, rel);
1873 INPUT_CLEANSE_BITMASK(dev, ABS, abs);
1874 INPUT_CLEANSE_BITMASK(dev, MSC, msc);
1875 INPUT_CLEANSE_BITMASK(dev, LED, led);
1876 INPUT_CLEANSE_BITMASK(dev, SND, snd);
1877 INPUT_CLEANSE_BITMASK(dev, FF, ff);
1878 INPUT_CLEANSE_BITMASK(dev, SW, sw);
1882 * input_register_device - register device with input core
1883 * @dev: device to be registered
1885 * This function registers device with input core. The device must be
1886 * allocated with input_allocate_device() and all it's capabilities
1887 * set up before registering.
1888 * If function fails the device must be freed with input_free_device().
1889 * Once device has been successfully registered it can be unregistered
1890 * with input_unregister_device(); input_free_device() should not be
1891 * called in this case.
1893 int input_register_device(struct input_dev *dev)
1895 static atomic_t input_no = ATOMIC_INIT(0);
1896 struct input_handler *handler;
1897 unsigned int packet_size;
1901 /* Every input device generates EV_SYN/SYN_REPORT events. */
1902 __set_bit(EV_SYN, dev->evbit);
1904 /* KEY_RESERVED is not supposed to be transmitted to userspace. */
1905 __clear_bit(KEY_RESERVED, dev->keybit);
1907 /* Make sure that bitmasks not mentioned in dev->evbit are clean. */
1908 input_cleanse_bitmasks(dev);
1910 packet_size = input_estimate_events_per_packet(dev);
1911 if (dev->hint_events_per_packet < packet_size)
1912 dev->hint_events_per_packet = packet_size;
1914 dev->max_vals = max(dev->hint_events_per_packet, packet_size) + 2;
1915 dev->vals = kcalloc(dev->max_vals, sizeof(*dev->vals), GFP_KERNEL);
1920 * If delay and period are pre-set by the driver, then autorepeating
1921 * is handled by the driver itself and we don't do it in input.c.
1923 init_timer(&dev->timer);
1924 if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
1925 dev->timer.data = (long) dev;
1926 dev->timer.function = input_repeat_key;
1927 dev->rep[REP_DELAY] = 250;
1928 dev->rep[REP_PERIOD] = 33;
1931 if (!dev->getkeycode)
1932 dev->getkeycode = input_default_getkeycode;
1934 if (!dev->setkeycode)
1935 dev->setkeycode = input_default_setkeycode;
1937 dev_set_name(&dev->dev, "input%ld",
1938 (unsigned long) atomic_inc_return(&input_no) - 1);
1940 error = device_add(&dev->dev);
1944 path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1945 pr_info("%s as %s\n",
1946 dev->name ? dev->name : "Unspecified device",
1947 path ? path : "N/A");
1950 error = mutex_lock_interruptible(&input_mutex);
1952 device_del(&dev->dev);
1956 list_add_tail(&dev->node, &input_dev_list);
1958 list_for_each_entry(handler, &input_handler_list, node)
1959 input_attach_handler(dev, handler);
1961 input_wakeup_procfs_readers();
1963 mutex_unlock(&input_mutex);
1967 EXPORT_SYMBOL(input_register_device);
1970 * input_unregister_device - unregister previously registered device
1971 * @dev: device to be unregistered
1973 * This function unregisters an input device. Once device is unregistered
1974 * the caller should not try to access it as it may get freed at any moment.
1976 void input_unregister_device(struct input_dev *dev)
1978 struct input_handle *handle, *next;
1980 input_disconnect_device(dev);
1982 mutex_lock(&input_mutex);
1984 list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
1985 handle->handler->disconnect(handle);
1986 WARN_ON(!list_empty(&dev->h_list));
1988 del_timer_sync(&dev->timer);
1989 list_del_init(&dev->node);
1991 input_wakeup_procfs_readers();
1993 mutex_unlock(&input_mutex);
1995 device_unregister(&dev->dev);
1997 EXPORT_SYMBOL(input_unregister_device);
2000 * input_register_handler - register a new input handler
2001 * @handler: handler to be registered
2003 * This function registers a new input handler (interface) for input
2004 * devices in the system and attaches it to all input devices that
2005 * are compatible with the handler.
2007 int input_register_handler(struct input_handler *handler)
2009 struct input_dev *dev;
2012 retval = mutex_lock_interruptible(&input_mutex);
2016 INIT_LIST_HEAD(&handler->h_list);
2018 if (handler->fops != NULL) {
2019 if (input_table[handler->minor >> 5]) {
2023 input_table[handler->minor >> 5] = handler;
2026 list_add_tail(&handler->node, &input_handler_list);
2028 list_for_each_entry(dev, &input_dev_list, node)
2029 input_attach_handler(dev, handler);
2031 input_wakeup_procfs_readers();
2034 mutex_unlock(&input_mutex);
2037 EXPORT_SYMBOL(input_register_handler);
2040 * input_unregister_handler - unregisters an input handler
2041 * @handler: handler to be unregistered
2043 * This function disconnects a handler from its input devices and
2044 * removes it from lists of known handlers.
2046 void input_unregister_handler(struct input_handler *handler)
2048 struct input_handle *handle, *next;
2050 mutex_lock(&input_mutex);
2052 list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
2053 handler->disconnect(handle);
2054 WARN_ON(!list_empty(&handler->h_list));
2056 list_del_init(&handler->node);
2058 if (handler->fops != NULL)
2059 input_table[handler->minor >> 5] = NULL;
2061 input_wakeup_procfs_readers();
2063 mutex_unlock(&input_mutex);
2065 EXPORT_SYMBOL(input_unregister_handler);
2068 * input_handler_for_each_handle - handle iterator
2069 * @handler: input handler to iterate
2070 * @data: data for the callback
2071 * @fn: function to be called for each handle
2073 * Iterate over @bus's list of devices, and call @fn for each, passing
2074 * it @data and stop when @fn returns a non-zero value. The function is
2075 * using RCU to traverse the list and therefore may be usind in atonic
2076 * contexts. The @fn callback is invoked from RCU critical section and
2077 * thus must not sleep.
2079 int input_handler_for_each_handle(struct input_handler *handler, void *data,
2080 int (*fn)(struct input_handle *, void *))
2082 struct input_handle *handle;
2087 list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
2088 retval = fn(handle, data);
2097 EXPORT_SYMBOL(input_handler_for_each_handle);
2100 * input_register_handle - register a new input handle
2101 * @handle: handle to register
2103 * This function puts a new input handle onto device's
2104 * and handler's lists so that events can flow through
2105 * it once it is opened using input_open_device().
2107 * This function is supposed to be called from handler's
2110 int input_register_handle(struct input_handle *handle)
2112 struct input_handler *handler = handle->handler;
2113 struct input_dev *dev = handle->dev;
2117 * We take dev->mutex here to prevent race with
2118 * input_release_device().
2120 error = mutex_lock_interruptible(&dev->mutex);
2125 * Filters go to the head of the list, normal handlers
2128 if (handler->filter)
2129 list_add_rcu(&handle->d_node, &dev->h_list);
2131 list_add_tail_rcu(&handle->d_node, &dev->h_list);
2133 mutex_unlock(&dev->mutex);
2136 * Since we are supposed to be called from ->connect()
2137 * which is mutually exclusive with ->disconnect()
2138 * we can't be racing with input_unregister_handle()
2139 * and so separate lock is not needed here.
2141 list_add_tail_rcu(&handle->h_node, &handler->h_list);
2144 handler->start(handle);
2148 EXPORT_SYMBOL(input_register_handle);
2151 * input_unregister_handle - unregister an input handle
2152 * @handle: handle to unregister
2154 * This function removes input handle from device's
2155 * and handler's lists.
2157 * This function is supposed to be called from handler's
2158 * disconnect() method.
2160 void input_unregister_handle(struct input_handle *handle)
2162 struct input_dev *dev = handle->dev;
2164 list_del_rcu(&handle->h_node);
2167 * Take dev->mutex to prevent race with input_release_device().
2169 mutex_lock(&dev->mutex);
2170 list_del_rcu(&handle->d_node);
2171 mutex_unlock(&dev->mutex);
2175 EXPORT_SYMBOL(input_unregister_handle);
2177 static int input_open_file(struct inode *inode, struct file *file)
2179 struct input_handler *handler;
2180 const struct file_operations *old_fops, *new_fops = NULL;
2183 err = mutex_lock_interruptible(&input_mutex);
2187 /* No load-on-demand here? */
2188 handler = input_table[iminor(inode) >> 5];
2190 new_fops = fops_get(handler->fops);
2192 mutex_unlock(&input_mutex);
2195 * That's _really_ odd. Usually NULL ->open means "nothing special",
2196 * not "no device". Oh, well...
2198 if (!new_fops || !new_fops->open) {
2204 old_fops = file->f_op;
2205 file->f_op = new_fops;
2207 err = new_fops->open(inode, file);
2209 fops_put(file->f_op);
2210 file->f_op = fops_get(old_fops);
2217 static const struct file_operations input_fops = {
2218 .owner = THIS_MODULE,
2219 .open = input_open_file,
2220 .llseek = noop_llseek,
2223 static int __init input_init(void)
2227 err = class_register(&input_class);
2229 pr_err("unable to register input_dev class\n");
2233 err = input_proc_init();
2237 err = register_chrdev(INPUT_MAJOR, "input", &input_fops);
2239 pr_err("unable to register char major %d", INPUT_MAJOR);
2245 fail2: input_proc_exit();
2246 fail1: class_unregister(&input_class);
2250 static void __exit input_exit(void)
2253 unregister_chrdev(INPUT_MAJOR, "input");
2254 class_unregister(&input_class);
2257 subsys_initcall(input_init);
2258 module_exit(input_exit);