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 <linux/smp_lock.h>
30 #include "input-compat.h"
32 MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
33 MODULE_DESCRIPTION("Input core");
34 MODULE_LICENSE("GPL");
36 #define INPUT_DEVICES 256
38 static LIST_HEAD(input_dev_list);
39 static LIST_HEAD(input_handler_list);
42 * input_mutex protects access to both input_dev_list and input_handler_list.
43 * This also causes input_[un]register_device and input_[un]register_handler
44 * be mutually exclusive which simplifies locking in drivers implementing
47 static DEFINE_MUTEX(input_mutex);
49 static struct input_handler *input_table[8];
51 static inline int is_event_supported(unsigned int code,
52 unsigned long *bm, unsigned int max)
54 return code <= max && test_bit(code, bm);
57 static int input_defuzz_abs_event(int value, int old_val, int fuzz)
60 if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
63 if (value > old_val - fuzz && value < old_val + fuzz)
64 return (old_val * 3 + value) / 4;
66 if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
67 return (old_val + value) / 2;
74 * Pass event first through all filters and then, if event has not been
75 * filtered out, through all open handles. This function is called with
76 * dev->event_lock held and interrupts disabled.
78 static void input_pass_event(struct input_dev *dev,
79 struct input_handler *src_handler,
80 unsigned int type, unsigned int code, int value)
82 struct input_handler *handler;
83 struct input_handle *handle;
87 handle = rcu_dereference(dev->grab);
89 handle->handler->event(handle, type, code, value);
91 bool filtered = false;
93 list_for_each_entry_rcu(handle, &dev->h_list, d_node) {
97 handler = handle->handler;
100 * If this is the handler that injected this
101 * particular event we want to skip it to avoid
102 * filters firing again and again.
104 if (handler == src_handler)
107 if (!handler->filter) {
111 handler->event(handle, type, code, value);
113 } else if (handler->filter(handle, type, code, value))
122 * Generate software autorepeat event. Note that we take
123 * dev->event_lock here to avoid racing with input_event
124 * which may cause keys get "stuck".
126 static void input_repeat_key(unsigned long data)
128 struct input_dev *dev = (void *) data;
131 spin_lock_irqsave(&dev->event_lock, flags);
133 if (test_bit(dev->repeat_key, dev->key) &&
134 is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
136 input_pass_event(dev, NULL, EV_KEY, dev->repeat_key, 2);
140 * Only send SYN_REPORT if we are not in a middle
141 * of driver parsing a new hardware packet.
142 * Otherwise assume that the driver will send
143 * SYN_REPORT once it's done.
145 input_pass_event(dev, NULL, EV_SYN, SYN_REPORT, 1);
148 if (dev->rep[REP_PERIOD])
149 mod_timer(&dev->timer, jiffies +
150 msecs_to_jiffies(dev->rep[REP_PERIOD]));
153 spin_unlock_irqrestore(&dev->event_lock, flags);
156 static void input_start_autorepeat(struct input_dev *dev, int code)
158 if (test_bit(EV_REP, dev->evbit) &&
159 dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
161 dev->repeat_key = code;
162 mod_timer(&dev->timer,
163 jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
167 static void input_stop_autorepeat(struct input_dev *dev)
169 del_timer(&dev->timer);
172 #define INPUT_IGNORE_EVENT 0
173 #define INPUT_PASS_TO_HANDLERS 1
174 #define INPUT_PASS_TO_DEVICE 2
175 #define INPUT_PASS_TO_ALL (INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
177 static int input_handle_abs_event(struct input_dev *dev,
178 struct input_handler *src_handler,
179 unsigned int code, int *pval)
184 if (code == ABS_MT_SLOT) {
186 * "Stage" the event; we'll flush it later, when we
187 * get actual touch data.
189 if (*pval >= 0 && *pval < dev->mtsize)
192 return INPUT_IGNORE_EVENT;
195 is_mt_event = code >= ABS_MT_FIRST && code <= ABS_MT_LAST;
198 pold = &dev->absinfo[code].value;
199 } else if (dev->mt) {
200 struct input_mt_slot *mtslot = &dev->mt[dev->slot];
201 pold = &mtslot->abs[code - ABS_MT_FIRST];
204 * Bypass filtering for multi-touch events when
205 * not employing slots.
211 *pval = input_defuzz_abs_event(*pval, *pold,
212 dev->absinfo[code].fuzz);
214 return INPUT_IGNORE_EVENT;
219 /* Flush pending "slot" event */
220 if (is_mt_event && dev->slot != input_abs_get_val(dev, ABS_MT_SLOT)) {
221 input_abs_set_val(dev, ABS_MT_SLOT, dev->slot);
222 input_pass_event(dev, src_handler,
223 EV_ABS, ABS_MT_SLOT, dev->slot);
226 return INPUT_PASS_TO_HANDLERS;
229 static void input_handle_event(struct input_dev *dev,
230 struct input_handler *src_handler,
231 unsigned int type, unsigned int code, int value)
233 int disposition = INPUT_IGNORE_EVENT;
240 disposition = INPUT_PASS_TO_ALL;
246 disposition = INPUT_PASS_TO_HANDLERS;
251 disposition = INPUT_PASS_TO_HANDLERS;
257 if (is_event_supported(code, dev->keybit, KEY_MAX) &&
258 !!test_bit(code, dev->key) != value) {
261 __change_bit(code, dev->key);
263 input_start_autorepeat(dev, code);
265 input_stop_autorepeat(dev);
268 disposition = INPUT_PASS_TO_HANDLERS;
273 if (is_event_supported(code, dev->swbit, SW_MAX) &&
274 !!test_bit(code, dev->sw) != value) {
276 __change_bit(code, dev->sw);
277 disposition = INPUT_PASS_TO_HANDLERS;
282 if (is_event_supported(code, dev->absbit, ABS_MAX))
283 disposition = input_handle_abs_event(dev, src_handler,
289 if (is_event_supported(code, dev->relbit, REL_MAX) && value)
290 disposition = INPUT_PASS_TO_HANDLERS;
295 if (is_event_supported(code, dev->mscbit, MSC_MAX))
296 disposition = INPUT_PASS_TO_ALL;
301 if (is_event_supported(code, dev->ledbit, LED_MAX) &&
302 !!test_bit(code, dev->led) != value) {
304 __change_bit(code, dev->led);
305 disposition = INPUT_PASS_TO_ALL;
310 if (is_event_supported(code, dev->sndbit, SND_MAX)) {
312 if (!!test_bit(code, dev->snd) != !!value)
313 __change_bit(code, dev->snd);
314 disposition = INPUT_PASS_TO_ALL;
319 if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
320 dev->rep[code] = value;
321 disposition = INPUT_PASS_TO_ALL;
327 disposition = INPUT_PASS_TO_ALL;
331 disposition = INPUT_PASS_TO_ALL;
335 if (disposition != INPUT_IGNORE_EVENT && type != EV_SYN)
338 if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
339 dev->event(dev, type, code, value);
341 if (disposition & INPUT_PASS_TO_HANDLERS)
342 input_pass_event(dev, src_handler, type, code, value);
346 * input_event() - report new input event
347 * @dev: device that generated the event
348 * @type: type of the event
350 * @value: value of the event
352 * This function should be used by drivers implementing various input
353 * devices to report input events. See also input_inject_event().
355 * NOTE: input_event() may be safely used right after input device was
356 * allocated with input_allocate_device(), even before it is registered
357 * with input_register_device(), but the event will not reach any of the
358 * input handlers. Such early invocation of input_event() may be used
359 * to 'seed' initial state of a switch or initial position of absolute
362 void input_event(struct input_dev *dev,
363 unsigned int type, unsigned int code, int value)
367 if (is_event_supported(type, dev->evbit, EV_MAX)) {
369 spin_lock_irqsave(&dev->event_lock, flags);
370 add_input_randomness(type, code, value);
371 input_handle_event(dev, NULL, type, code, value);
372 spin_unlock_irqrestore(&dev->event_lock, flags);
375 EXPORT_SYMBOL(input_event);
378 * input_inject_event() - send input event from input handler
379 * @handle: input handle to send event through
380 * @type: type of the event
382 * @value: value of the event
384 * Similar to input_event() but will ignore event if device is
385 * "grabbed" and handle injecting event is not the one that owns
388 void input_inject_event(struct input_handle *handle,
389 unsigned int type, unsigned int code, int value)
391 struct input_dev *dev = handle->dev;
392 struct input_handle *grab;
395 if (is_event_supported(type, dev->evbit, EV_MAX)) {
396 spin_lock_irqsave(&dev->event_lock, flags);
399 grab = rcu_dereference(dev->grab);
400 if (!grab || grab == handle)
401 input_handle_event(dev, handle->handler,
405 spin_unlock_irqrestore(&dev->event_lock, flags);
408 EXPORT_SYMBOL(input_inject_event);
411 * input_alloc_absinfo - allocates array of input_absinfo structs
412 * @dev: the input device emitting absolute events
414 * If the absinfo struct the caller asked for is already allocated, this
415 * functions will not do anything.
417 void input_alloc_absinfo(struct input_dev *dev)
420 dev->absinfo = kcalloc(ABS_CNT, sizeof(struct input_absinfo),
423 WARN(!dev->absinfo, "%s(): kcalloc() failed?\n", __func__);
425 EXPORT_SYMBOL(input_alloc_absinfo);
427 void input_set_abs_params(struct input_dev *dev, unsigned int axis,
428 int min, int max, int fuzz, int flat)
430 struct input_absinfo *absinfo;
432 input_alloc_absinfo(dev);
436 absinfo = &dev->absinfo[axis];
437 absinfo->minimum = min;
438 absinfo->maximum = max;
439 absinfo->fuzz = fuzz;
440 absinfo->flat = flat;
442 dev->absbit[BIT_WORD(axis)] |= BIT_MASK(axis);
444 EXPORT_SYMBOL(input_set_abs_params);
448 * input_grab_device - grabs device for exclusive use
449 * @handle: input handle that wants to own the device
451 * When a device is grabbed by an input handle all events generated by
452 * the device are delivered only to this handle. Also events injected
453 * by other input handles are ignored while device is grabbed.
455 int input_grab_device(struct input_handle *handle)
457 struct input_dev *dev = handle->dev;
460 retval = mutex_lock_interruptible(&dev->mutex);
469 rcu_assign_pointer(dev->grab, handle);
473 mutex_unlock(&dev->mutex);
476 EXPORT_SYMBOL(input_grab_device);
478 static void __input_release_device(struct input_handle *handle)
480 struct input_dev *dev = handle->dev;
482 if (dev->grab == handle) {
483 rcu_assign_pointer(dev->grab, NULL);
484 /* Make sure input_pass_event() notices that grab is gone */
487 list_for_each_entry(handle, &dev->h_list, d_node)
488 if (handle->open && handle->handler->start)
489 handle->handler->start(handle);
494 * input_release_device - release previously grabbed device
495 * @handle: input handle that owns the device
497 * Releases previously grabbed device so that other input handles can
498 * start receiving input events. Upon release all handlers attached
499 * to the device have their start() method called so they have a change
500 * to synchronize device state with the rest of the system.
502 void input_release_device(struct input_handle *handle)
504 struct input_dev *dev = handle->dev;
506 mutex_lock(&dev->mutex);
507 __input_release_device(handle);
508 mutex_unlock(&dev->mutex);
510 EXPORT_SYMBOL(input_release_device);
513 * input_open_device - open input device
514 * @handle: handle through which device is being accessed
516 * This function should be called by input handlers when they
517 * want to start receive events from given input device.
519 int input_open_device(struct input_handle *handle)
521 struct input_dev *dev = handle->dev;
524 retval = mutex_lock_interruptible(&dev->mutex);
528 if (dev->going_away) {
535 if (!dev->users++ && dev->open)
536 retval = dev->open(dev);
540 if (!--handle->open) {
542 * Make sure we are not delivering any more events
543 * through this handle
550 mutex_unlock(&dev->mutex);
553 EXPORT_SYMBOL(input_open_device);
555 int input_flush_device(struct input_handle *handle, struct file *file)
557 struct input_dev *dev = handle->dev;
560 retval = mutex_lock_interruptible(&dev->mutex);
565 retval = dev->flush(dev, file);
567 mutex_unlock(&dev->mutex);
570 EXPORT_SYMBOL(input_flush_device);
573 * input_close_device - close input device
574 * @handle: handle through which device is being accessed
576 * This function should be called by input handlers when they
577 * want to stop receive events from given input device.
579 void input_close_device(struct input_handle *handle)
581 struct input_dev *dev = handle->dev;
583 mutex_lock(&dev->mutex);
585 __input_release_device(handle);
587 if (!--dev->users && dev->close)
590 if (!--handle->open) {
592 * synchronize_rcu() makes sure that input_pass_event()
593 * completed and that no more input events are delivered
594 * through this handle
599 mutex_unlock(&dev->mutex);
601 EXPORT_SYMBOL(input_close_device);
604 * Simulate keyup events for all keys that are marked as pressed.
605 * The function must be called with dev->event_lock held.
607 static void input_dev_release_keys(struct input_dev *dev)
611 if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
612 for (code = 0; code <= KEY_MAX; code++) {
613 if (is_event_supported(code, dev->keybit, KEY_MAX) &&
614 __test_and_clear_bit(code, dev->key)) {
615 input_pass_event(dev, NULL, EV_KEY, code, 0);
618 input_pass_event(dev, NULL, EV_SYN, SYN_REPORT, 1);
623 * Prepare device for unregistering
625 static void input_disconnect_device(struct input_dev *dev)
627 struct input_handle *handle;
630 * Mark device as going away. Note that we take dev->mutex here
631 * not to protect access to dev->going_away but rather to ensure
632 * that there are no threads in the middle of input_open_device()
634 mutex_lock(&dev->mutex);
635 dev->going_away = true;
636 mutex_unlock(&dev->mutex);
638 spin_lock_irq(&dev->event_lock);
641 * Simulate keyup events for all pressed keys so that handlers
642 * are not left with "stuck" keys. The driver may continue
643 * generate events even after we done here but they will not
644 * reach any handlers.
646 input_dev_release_keys(dev);
648 list_for_each_entry(handle, &dev->h_list, d_node)
651 spin_unlock_irq(&dev->event_lock);
655 * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
656 * @ke: keymap entry containing scancode to be converted.
657 * @scancode: pointer to the location where converted scancode should
660 * This function is used to convert scancode stored in &struct keymap_entry
661 * into scalar form understood by legacy keymap handling methods. These
662 * methods expect scancodes to be represented as 'unsigned int'.
664 int input_scancode_to_scalar(const struct input_keymap_entry *ke,
665 unsigned int *scancode)
669 *scancode = *((u8 *)ke->scancode);
673 *scancode = *((u16 *)ke->scancode);
677 *scancode = *((u32 *)ke->scancode);
686 EXPORT_SYMBOL(input_scancode_to_scalar);
689 * Those routines handle the default case where no [gs]etkeycode() is
690 * defined. In this case, an array indexed by the scancode is used.
693 static unsigned int input_fetch_keycode(struct input_dev *dev,
696 switch (dev->keycodesize) {
698 return ((u8 *)dev->keycode)[index];
701 return ((u16 *)dev->keycode)[index];
704 return ((u32 *)dev->keycode)[index];
708 static int input_default_getkeycode(struct input_dev *dev,
709 struct input_keymap_entry *ke)
714 if (!dev->keycodesize)
717 if (ke->flags & INPUT_KEYMAP_BY_INDEX)
720 error = input_scancode_to_scalar(ke, &index);
725 if (index >= dev->keycodemax)
728 ke->keycode = input_fetch_keycode(dev, index);
730 ke->len = sizeof(index);
731 memcpy(ke->scancode, &index, sizeof(index));
736 static int input_default_setkeycode(struct input_dev *dev,
737 const struct input_keymap_entry *ke,
738 unsigned int *old_keycode)
744 if (!dev->keycodesize)
747 if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
750 error = input_scancode_to_scalar(ke, &index);
755 if (index >= dev->keycodemax)
758 if (dev->keycodesize < sizeof(ke->keycode) &&
759 (ke->keycode >> (dev->keycodesize * 8)))
762 switch (dev->keycodesize) {
764 u8 *k = (u8 *)dev->keycode;
765 *old_keycode = k[index];
766 k[index] = ke->keycode;
770 u16 *k = (u16 *)dev->keycode;
771 *old_keycode = k[index];
772 k[index] = ke->keycode;
776 u32 *k = (u32 *)dev->keycode;
777 *old_keycode = k[index];
778 k[index] = ke->keycode;
783 __clear_bit(*old_keycode, dev->keybit);
784 __set_bit(ke->keycode, dev->keybit);
786 for (i = 0; i < dev->keycodemax; i++) {
787 if (input_fetch_keycode(dev, i) == *old_keycode) {
788 __set_bit(*old_keycode, dev->keybit);
789 break; /* Setting the bit twice is useless, so break */
797 * input_get_keycode - retrieve keycode currently mapped to a given scancode
798 * @dev: input device which keymap is being queried
801 * This function should be called by anyone interested in retrieving current
802 * keymap. Presently evdev handlers use it.
804 int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
809 spin_lock_irqsave(&dev->event_lock, flags);
811 if (dev->getkeycode) {
813 * Support for legacy drivers, that don't implement the new
816 u32 scancode = ke->index;
818 memcpy(ke->scancode, &scancode, sizeof(scancode));
819 ke->len = sizeof(scancode);
820 retval = dev->getkeycode(dev, scancode, &ke->keycode);
822 retval = dev->getkeycode_new(dev, ke);
825 spin_unlock_irqrestore(&dev->event_lock, flags);
828 EXPORT_SYMBOL(input_get_keycode);
831 * input_set_keycode - attribute a keycode to a given scancode
832 * @dev: input device which keymap is being updated
833 * @ke: new keymap entry
835 * This function should be called by anyone needing to update current
836 * keymap. Presently keyboard and evdev handlers use it.
838 int input_set_keycode(struct input_dev *dev,
839 const struct input_keymap_entry *ke)
842 unsigned int old_keycode;
845 if (ke->keycode > KEY_MAX)
848 spin_lock_irqsave(&dev->event_lock, flags);
850 if (dev->setkeycode) {
852 * Support for legacy drivers, that don't implement the new
855 unsigned int scancode;
857 retval = input_scancode_to_scalar(ke, &scancode);
862 * We need to know the old scancode, in order to generate a
863 * keyup effect, if the set operation happens successfully
865 if (!dev->getkeycode) {
870 retval = dev->getkeycode(dev, scancode, &old_keycode);
874 retval = dev->setkeycode(dev, scancode, ke->keycode);
876 retval = dev->setkeycode_new(dev, ke, &old_keycode);
882 /* Make sure KEY_RESERVED did not get enabled. */
883 __clear_bit(KEY_RESERVED, dev->keybit);
886 * Simulate keyup event if keycode is not present
887 * in the keymap anymore
889 if (test_bit(EV_KEY, dev->evbit) &&
890 !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
891 __test_and_clear_bit(old_keycode, dev->key)) {
893 input_pass_event(dev, NULL, EV_KEY, old_keycode, 0);
895 input_pass_event(dev, NULL, EV_SYN, SYN_REPORT, 1);
899 spin_unlock_irqrestore(&dev->event_lock, flags);
903 EXPORT_SYMBOL(input_set_keycode);
905 #define MATCH_BIT(bit, max) \
906 for (i = 0; i < BITS_TO_LONGS(max); i++) \
907 if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \
909 if (i != BITS_TO_LONGS(max)) \
912 static const struct input_device_id *input_match_device(struct input_handler *handler,
913 struct input_dev *dev)
915 const struct input_device_id *id;
918 for (id = handler->id_table; id->flags || id->driver_info; id++) {
920 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
921 if (id->bustype != dev->id.bustype)
924 if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
925 if (id->vendor != dev->id.vendor)
928 if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
929 if (id->product != dev->id.product)
932 if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
933 if (id->version != dev->id.version)
936 MATCH_BIT(evbit, EV_MAX);
937 MATCH_BIT(keybit, KEY_MAX);
938 MATCH_BIT(relbit, REL_MAX);
939 MATCH_BIT(absbit, ABS_MAX);
940 MATCH_BIT(mscbit, MSC_MAX);
941 MATCH_BIT(ledbit, LED_MAX);
942 MATCH_BIT(sndbit, SND_MAX);
943 MATCH_BIT(ffbit, FF_MAX);
944 MATCH_BIT(swbit, SW_MAX);
946 if (!handler->match || handler->match(handler, dev))
953 static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
955 const struct input_device_id *id;
958 id = input_match_device(handler, dev);
962 error = handler->connect(handler, dev, id);
963 if (error && error != -ENODEV)
964 pr_err("failed to attach handler %s to device %s, error: %d\n",
965 handler->name, kobject_name(&dev->dev.kobj), error);
972 static int input_bits_to_string(char *buf, int buf_size,
973 unsigned long bits, bool skip_empty)
977 if (INPUT_COMPAT_TEST) {
978 u32 dword = bits >> 32;
979 if (dword || !skip_empty)
980 len += snprintf(buf, buf_size, "%x ", dword);
982 dword = bits & 0xffffffffUL;
983 if (dword || !skip_empty || len)
984 len += snprintf(buf + len, max(buf_size - len, 0),
987 if (bits || !skip_empty)
988 len += snprintf(buf, buf_size, "%lx", bits);
994 #else /* !CONFIG_COMPAT */
996 static int input_bits_to_string(char *buf, int buf_size,
997 unsigned long bits, bool skip_empty)
999 return bits || !skip_empty ?
1000 snprintf(buf, buf_size, "%lx", bits) : 0;
1005 #ifdef CONFIG_PROC_FS
1007 static struct proc_dir_entry *proc_bus_input_dir;
1008 static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
1009 static int input_devices_state;
1011 static inline void input_wakeup_procfs_readers(void)
1013 input_devices_state++;
1014 wake_up(&input_devices_poll_wait);
1017 static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
1019 poll_wait(file, &input_devices_poll_wait, wait);
1020 if (file->f_version != input_devices_state) {
1021 file->f_version = input_devices_state;
1022 return POLLIN | POLLRDNORM;
1028 union input_seq_state {
1031 bool mutex_acquired;
1036 static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
1038 union input_seq_state *state = (union input_seq_state *)&seq->private;
1041 /* We need to fit into seq->private pointer */
1042 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1044 error = mutex_lock_interruptible(&input_mutex);
1046 state->mutex_acquired = false;
1047 return ERR_PTR(error);
1050 state->mutex_acquired = true;
1052 return seq_list_start(&input_dev_list, *pos);
1055 static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1057 return seq_list_next(v, &input_dev_list, pos);
1060 static void input_seq_stop(struct seq_file *seq, void *v)
1062 union input_seq_state *state = (union input_seq_state *)&seq->private;
1064 if (state->mutex_acquired)
1065 mutex_unlock(&input_mutex);
1068 static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
1069 unsigned long *bitmap, int max)
1072 bool skip_empty = true;
1075 seq_printf(seq, "B: %s=", name);
1077 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1078 if (input_bits_to_string(buf, sizeof(buf),
1079 bitmap[i], skip_empty)) {
1081 seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
1086 * If no output was produced print a single 0.
1091 seq_putc(seq, '\n');
1094 static int input_devices_seq_show(struct seq_file *seq, void *v)
1096 struct input_dev *dev = container_of(v, struct input_dev, node);
1097 const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1098 struct input_handle *handle;
1100 seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
1101 dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
1103 seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
1104 seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
1105 seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
1106 seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
1107 seq_printf(seq, "H: Handlers=");
1109 list_for_each_entry(handle, &dev->h_list, d_node)
1110 seq_printf(seq, "%s ", handle->name);
1111 seq_putc(seq, '\n');
1113 input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
1115 input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
1116 if (test_bit(EV_KEY, dev->evbit))
1117 input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
1118 if (test_bit(EV_REL, dev->evbit))
1119 input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
1120 if (test_bit(EV_ABS, dev->evbit))
1121 input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
1122 if (test_bit(EV_MSC, dev->evbit))
1123 input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
1124 if (test_bit(EV_LED, dev->evbit))
1125 input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
1126 if (test_bit(EV_SND, dev->evbit))
1127 input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
1128 if (test_bit(EV_FF, dev->evbit))
1129 input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
1130 if (test_bit(EV_SW, dev->evbit))
1131 input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
1133 seq_putc(seq, '\n');
1139 static const struct seq_operations input_devices_seq_ops = {
1140 .start = input_devices_seq_start,
1141 .next = input_devices_seq_next,
1142 .stop = input_seq_stop,
1143 .show = input_devices_seq_show,
1146 static int input_proc_devices_open(struct inode *inode, struct file *file)
1148 return seq_open(file, &input_devices_seq_ops);
1151 static const struct file_operations input_devices_fileops = {
1152 .owner = THIS_MODULE,
1153 .open = input_proc_devices_open,
1154 .poll = input_proc_devices_poll,
1156 .llseek = seq_lseek,
1157 .release = seq_release,
1160 static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
1162 union input_seq_state *state = (union input_seq_state *)&seq->private;
1165 /* We need to fit into seq->private pointer */
1166 BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
1168 error = mutex_lock_interruptible(&input_mutex);
1170 state->mutex_acquired = false;
1171 return ERR_PTR(error);
1174 state->mutex_acquired = true;
1177 return seq_list_start(&input_handler_list, *pos);
1180 static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1182 union input_seq_state *state = (union input_seq_state *)&seq->private;
1184 state->pos = *pos + 1;
1185 return seq_list_next(v, &input_handler_list, pos);
1188 static int input_handlers_seq_show(struct seq_file *seq, void *v)
1190 struct input_handler *handler = container_of(v, struct input_handler, node);
1191 union input_seq_state *state = (union input_seq_state *)&seq->private;
1193 seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
1194 if (handler->filter)
1195 seq_puts(seq, " (filter)");
1197 seq_printf(seq, " Minor=%d", handler->minor);
1198 seq_putc(seq, '\n');
1203 static const struct seq_operations input_handlers_seq_ops = {
1204 .start = input_handlers_seq_start,
1205 .next = input_handlers_seq_next,
1206 .stop = input_seq_stop,
1207 .show = input_handlers_seq_show,
1210 static int input_proc_handlers_open(struct inode *inode, struct file *file)
1212 return seq_open(file, &input_handlers_seq_ops);
1215 static const struct file_operations input_handlers_fileops = {
1216 .owner = THIS_MODULE,
1217 .open = input_proc_handlers_open,
1219 .llseek = seq_lseek,
1220 .release = seq_release,
1223 static int __init input_proc_init(void)
1225 struct proc_dir_entry *entry;
1227 proc_bus_input_dir = proc_mkdir("bus/input", NULL);
1228 if (!proc_bus_input_dir)
1231 entry = proc_create("devices", 0, proc_bus_input_dir,
1232 &input_devices_fileops);
1236 entry = proc_create("handlers", 0, proc_bus_input_dir,
1237 &input_handlers_fileops);
1243 fail2: remove_proc_entry("devices", proc_bus_input_dir);
1244 fail1: remove_proc_entry("bus/input", NULL);
1248 static void input_proc_exit(void)
1250 remove_proc_entry("devices", proc_bus_input_dir);
1251 remove_proc_entry("handlers", proc_bus_input_dir);
1252 remove_proc_entry("bus/input", NULL);
1255 #else /* !CONFIG_PROC_FS */
1256 static inline void input_wakeup_procfs_readers(void) { }
1257 static inline int input_proc_init(void) { return 0; }
1258 static inline void input_proc_exit(void) { }
1261 #define INPUT_DEV_STRING_ATTR_SHOW(name) \
1262 static ssize_t input_dev_show_##name(struct device *dev, \
1263 struct device_attribute *attr, \
1266 struct input_dev *input_dev = to_input_dev(dev); \
1268 return scnprintf(buf, PAGE_SIZE, "%s\n", \
1269 input_dev->name ? input_dev->name : ""); \
1271 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
1273 INPUT_DEV_STRING_ATTR_SHOW(name);
1274 INPUT_DEV_STRING_ATTR_SHOW(phys);
1275 INPUT_DEV_STRING_ATTR_SHOW(uniq);
1277 static int input_print_modalias_bits(char *buf, int size,
1278 char name, unsigned long *bm,
1279 unsigned int min_bit, unsigned int max_bit)
1283 len += snprintf(buf, max(size, 0), "%c", name);
1284 for (i = min_bit; i < max_bit; i++)
1285 if (bm[BIT_WORD(i)] & BIT_MASK(i))
1286 len += snprintf(buf + len, max(size - len, 0), "%X,", i);
1290 static int input_print_modalias(char *buf, int size, struct input_dev *id,
1295 len = snprintf(buf, max(size, 0),
1296 "input:b%04Xv%04Xp%04Xe%04X-",
1297 id->id.bustype, id->id.vendor,
1298 id->id.product, id->id.version);
1300 len += input_print_modalias_bits(buf + len, size - len,
1301 'e', id->evbit, 0, EV_MAX);
1302 len += input_print_modalias_bits(buf + len, size - len,
1303 'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
1304 len += input_print_modalias_bits(buf + len, size - len,
1305 'r', id->relbit, 0, REL_MAX);
1306 len += input_print_modalias_bits(buf + len, size - len,
1307 'a', id->absbit, 0, ABS_MAX);
1308 len += input_print_modalias_bits(buf + len, size - len,
1309 'm', id->mscbit, 0, MSC_MAX);
1310 len += input_print_modalias_bits(buf + len, size - len,
1311 'l', id->ledbit, 0, LED_MAX);
1312 len += input_print_modalias_bits(buf + len, size - len,
1313 's', id->sndbit, 0, SND_MAX);
1314 len += input_print_modalias_bits(buf + len, size - len,
1315 'f', id->ffbit, 0, FF_MAX);
1316 len += input_print_modalias_bits(buf + len, size - len,
1317 'w', id->swbit, 0, SW_MAX);
1320 len += snprintf(buf + len, max(size - len, 0), "\n");
1325 static ssize_t input_dev_show_modalias(struct device *dev,
1326 struct device_attribute *attr,
1329 struct input_dev *id = to_input_dev(dev);
1332 len = input_print_modalias(buf, PAGE_SIZE, id, 1);
1334 return min_t(int, len, PAGE_SIZE);
1336 static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
1338 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1339 int max, int add_cr);
1341 static ssize_t input_dev_show_properties(struct device *dev,
1342 struct device_attribute *attr,
1345 struct input_dev *input_dev = to_input_dev(dev);
1346 int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
1347 INPUT_PROP_MAX, true);
1348 return min_t(int, len, PAGE_SIZE);
1350 static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
1352 static struct attribute *input_dev_attrs[] = {
1353 &dev_attr_name.attr,
1354 &dev_attr_phys.attr,
1355 &dev_attr_uniq.attr,
1356 &dev_attr_modalias.attr,
1357 &dev_attr_properties.attr,
1361 static struct attribute_group input_dev_attr_group = {
1362 .attrs = input_dev_attrs,
1365 #define INPUT_DEV_ID_ATTR(name) \
1366 static ssize_t input_dev_show_id_##name(struct device *dev, \
1367 struct device_attribute *attr, \
1370 struct input_dev *input_dev = to_input_dev(dev); \
1371 return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name); \
1373 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
1375 INPUT_DEV_ID_ATTR(bustype);
1376 INPUT_DEV_ID_ATTR(vendor);
1377 INPUT_DEV_ID_ATTR(product);
1378 INPUT_DEV_ID_ATTR(version);
1380 static struct attribute *input_dev_id_attrs[] = {
1381 &dev_attr_bustype.attr,
1382 &dev_attr_vendor.attr,
1383 &dev_attr_product.attr,
1384 &dev_attr_version.attr,
1388 static struct attribute_group input_dev_id_attr_group = {
1390 .attrs = input_dev_id_attrs,
1393 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
1394 int max, int add_cr)
1398 bool skip_empty = true;
1400 for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
1401 len += input_bits_to_string(buf + len, max(buf_size - len, 0),
1402 bitmap[i], skip_empty);
1406 len += snprintf(buf + len, max(buf_size - len, 0), " ");
1411 * If no output was produced print a single 0.
1414 len = snprintf(buf, buf_size, "%d", 0);
1417 len += snprintf(buf + len, max(buf_size - len, 0), "\n");
1422 #define INPUT_DEV_CAP_ATTR(ev, bm) \
1423 static ssize_t input_dev_show_cap_##bm(struct device *dev, \
1424 struct device_attribute *attr, \
1427 struct input_dev *input_dev = to_input_dev(dev); \
1428 int len = input_print_bitmap(buf, PAGE_SIZE, \
1429 input_dev->bm##bit, ev##_MAX, \
1431 return min_t(int, len, PAGE_SIZE); \
1433 static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
1435 INPUT_DEV_CAP_ATTR(EV, ev);
1436 INPUT_DEV_CAP_ATTR(KEY, key);
1437 INPUT_DEV_CAP_ATTR(REL, rel);
1438 INPUT_DEV_CAP_ATTR(ABS, abs);
1439 INPUT_DEV_CAP_ATTR(MSC, msc);
1440 INPUT_DEV_CAP_ATTR(LED, led);
1441 INPUT_DEV_CAP_ATTR(SND, snd);
1442 INPUT_DEV_CAP_ATTR(FF, ff);
1443 INPUT_DEV_CAP_ATTR(SW, sw);
1445 static struct attribute *input_dev_caps_attrs[] = {
1458 static struct attribute_group input_dev_caps_attr_group = {
1459 .name = "capabilities",
1460 .attrs = input_dev_caps_attrs,
1463 static const struct attribute_group *input_dev_attr_groups[] = {
1464 &input_dev_attr_group,
1465 &input_dev_id_attr_group,
1466 &input_dev_caps_attr_group,
1470 static void input_dev_release(struct device *device)
1472 struct input_dev *dev = to_input_dev(device);
1474 input_ff_destroy(dev);
1475 input_mt_destroy_slots(dev);
1476 kfree(dev->absinfo);
1479 module_put(THIS_MODULE);
1483 * Input uevent interface - loading event handlers based on
1486 static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
1487 const char *name, unsigned long *bitmap, int max)
1491 if (add_uevent_var(env, "%s", name))
1494 len = input_print_bitmap(&env->buf[env->buflen - 1],
1495 sizeof(env->buf) - env->buflen,
1496 bitmap, max, false);
1497 if (len >= (sizeof(env->buf) - env->buflen))
1504 static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
1505 struct input_dev *dev)
1509 if (add_uevent_var(env, "MODALIAS="))
1512 len = input_print_modalias(&env->buf[env->buflen - 1],
1513 sizeof(env->buf) - env->buflen,
1515 if (len >= (sizeof(env->buf) - env->buflen))
1522 #define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \
1524 int err = add_uevent_var(env, fmt, val); \
1529 #define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max) \
1531 int err = input_add_uevent_bm_var(env, name, bm, max); \
1536 #define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \
1538 int err = input_add_uevent_modalias_var(env, dev); \
1543 static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
1545 struct input_dev *dev = to_input_dev(device);
1547 INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
1548 dev->id.bustype, dev->id.vendor,
1549 dev->id.product, dev->id.version);
1551 INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
1553 INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
1555 INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
1557 INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
1559 INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
1560 if (test_bit(EV_KEY, dev->evbit))
1561 INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
1562 if (test_bit(EV_REL, dev->evbit))
1563 INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
1564 if (test_bit(EV_ABS, dev->evbit))
1565 INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
1566 if (test_bit(EV_MSC, dev->evbit))
1567 INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
1568 if (test_bit(EV_LED, dev->evbit))
1569 INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
1570 if (test_bit(EV_SND, dev->evbit))
1571 INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
1572 if (test_bit(EV_FF, dev->evbit))
1573 INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
1574 if (test_bit(EV_SW, dev->evbit))
1575 INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
1577 INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
1582 #define INPUT_DO_TOGGLE(dev, type, bits, on) \
1587 if (!test_bit(EV_##type, dev->evbit)) \
1590 for (i = 0; i < type##_MAX; i++) { \
1591 if (!test_bit(i, dev->bits##bit)) \
1594 active = test_bit(i, dev->bits); \
1595 if (!active && !on) \
1598 dev->event(dev, EV_##type, i, on ? active : 0); \
1602 static void input_dev_toggle(struct input_dev *dev, bool activate)
1607 INPUT_DO_TOGGLE(dev, LED, led, activate);
1608 INPUT_DO_TOGGLE(dev, SND, snd, activate);
1610 if (activate && test_bit(EV_REP, dev->evbit)) {
1611 dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
1612 dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
1617 * input_reset_device() - reset/restore the state of input device
1618 * @dev: input device whose state needs to be reset
1620 * This function tries to reset the state of an opened input device and
1621 * bring internal state and state if the hardware in sync with each other.
1622 * We mark all keys as released, restore LED state, repeat rate, etc.
1624 void input_reset_device(struct input_dev *dev)
1626 mutex_lock(&dev->mutex);
1629 input_dev_toggle(dev, true);
1632 * Keys that have been pressed at suspend time are unlikely
1633 * to be still pressed when we resume.
1635 spin_lock_irq(&dev->event_lock);
1636 input_dev_release_keys(dev);
1637 spin_unlock_irq(&dev->event_lock);
1640 mutex_unlock(&dev->mutex);
1642 EXPORT_SYMBOL(input_reset_device);
1645 static int input_dev_suspend(struct device *dev)
1647 struct input_dev *input_dev = to_input_dev(dev);
1649 mutex_lock(&input_dev->mutex);
1651 if (input_dev->users)
1652 input_dev_toggle(input_dev, false);
1654 mutex_unlock(&input_dev->mutex);
1659 static int input_dev_resume(struct device *dev)
1661 struct input_dev *input_dev = to_input_dev(dev);
1663 input_reset_device(input_dev);
1668 static const struct dev_pm_ops input_dev_pm_ops = {
1669 .suspend = input_dev_suspend,
1670 .resume = input_dev_resume,
1671 .poweroff = input_dev_suspend,
1672 .restore = input_dev_resume,
1674 #endif /* CONFIG_PM */
1676 static struct device_type input_dev_type = {
1677 .groups = input_dev_attr_groups,
1678 .release = input_dev_release,
1679 .uevent = input_dev_uevent,
1681 .pm = &input_dev_pm_ops,
1685 static char *input_devnode(struct device *dev, mode_t *mode)
1687 return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
1690 struct class input_class = {
1692 .devnode = input_devnode,
1694 EXPORT_SYMBOL_GPL(input_class);
1697 * input_allocate_device - allocate memory for new input device
1699 * Returns prepared struct input_dev or NULL.
1701 * NOTE: Use input_free_device() to free devices that have not been
1702 * registered; input_unregister_device() should be used for already
1703 * registered devices.
1705 struct input_dev *input_allocate_device(void)
1707 struct input_dev *dev;
1709 dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
1711 dev->dev.type = &input_dev_type;
1712 dev->dev.class = &input_class;
1713 device_initialize(&dev->dev);
1714 mutex_init(&dev->mutex);
1715 spin_lock_init(&dev->event_lock);
1716 INIT_LIST_HEAD(&dev->h_list);
1717 INIT_LIST_HEAD(&dev->node);
1719 __module_get(THIS_MODULE);
1724 EXPORT_SYMBOL(input_allocate_device);
1727 * input_free_device - free memory occupied by input_dev structure
1728 * @dev: input device to free
1730 * This function should only be used if input_register_device()
1731 * was not called yet or if it failed. Once device was registered
1732 * use input_unregister_device() and memory will be freed once last
1733 * reference to the device is dropped.
1735 * Device should be allocated by input_allocate_device().
1737 * NOTE: If there are references to the input device then memory
1738 * will not be freed until last reference is dropped.
1740 void input_free_device(struct input_dev *dev)
1743 input_put_device(dev);
1745 EXPORT_SYMBOL(input_free_device);
1748 * input_set_capability - mark device as capable of a certain event
1749 * @dev: device that is capable of emitting or accepting event
1750 * @type: type of the event (EV_KEY, EV_REL, etc...)
1753 * In addition to setting up corresponding bit in appropriate capability
1754 * bitmap the function also adjusts dev->evbit.
1756 void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
1760 __set_bit(code, dev->keybit);
1764 __set_bit(code, dev->relbit);
1768 __set_bit(code, dev->absbit);
1772 __set_bit(code, dev->mscbit);
1776 __set_bit(code, dev->swbit);
1780 __set_bit(code, dev->ledbit);
1784 __set_bit(code, dev->sndbit);
1788 __set_bit(code, dev->ffbit);
1796 pr_err("input_set_capability: unknown type %u (code %u)\n",
1802 __set_bit(type, dev->evbit);
1804 EXPORT_SYMBOL(input_set_capability);
1806 #define INPUT_CLEANSE_BITMASK(dev, type, bits) \
1808 if (!test_bit(EV_##type, dev->evbit)) \
1809 memset(dev->bits##bit, 0, \
1810 sizeof(dev->bits##bit)); \
1813 static void input_cleanse_bitmasks(struct input_dev *dev)
1815 INPUT_CLEANSE_BITMASK(dev, KEY, key);
1816 INPUT_CLEANSE_BITMASK(dev, REL, rel);
1817 INPUT_CLEANSE_BITMASK(dev, ABS, abs);
1818 INPUT_CLEANSE_BITMASK(dev, MSC, msc);
1819 INPUT_CLEANSE_BITMASK(dev, LED, led);
1820 INPUT_CLEANSE_BITMASK(dev, SND, snd);
1821 INPUT_CLEANSE_BITMASK(dev, FF, ff);
1822 INPUT_CLEANSE_BITMASK(dev, SW, sw);
1826 * input_register_device - register device with input core
1827 * @dev: device to be registered
1829 * This function registers device with input core. The device must be
1830 * allocated with input_allocate_device() and all it's capabilities
1831 * set up before registering.
1832 * If function fails the device must be freed with input_free_device().
1833 * Once device has been successfully registered it can be unregistered
1834 * with input_unregister_device(); input_free_device() should not be
1835 * called in this case.
1837 int input_register_device(struct input_dev *dev)
1839 static atomic_t input_no = ATOMIC_INIT(0);
1840 struct input_handler *handler;
1844 /* Every input device generates EV_SYN/SYN_REPORT events. */
1845 __set_bit(EV_SYN, dev->evbit);
1847 /* KEY_RESERVED is not supposed to be transmitted to userspace. */
1848 __clear_bit(KEY_RESERVED, dev->keybit);
1850 /* Make sure that bitmasks not mentioned in dev->evbit are clean. */
1851 input_cleanse_bitmasks(dev);
1854 * If delay and period are pre-set by the driver, then autorepeating
1855 * is handled by the driver itself and we don't do it in input.c.
1857 init_timer(&dev->timer);
1858 if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
1859 dev->timer.data = (long) dev;
1860 dev->timer.function = input_repeat_key;
1861 dev->rep[REP_DELAY] = 250;
1862 dev->rep[REP_PERIOD] = 33;
1865 if (!dev->getkeycode && !dev->getkeycode_new)
1866 dev->getkeycode_new = input_default_getkeycode;
1868 if (!dev->setkeycode && !dev->setkeycode_new)
1869 dev->setkeycode_new = input_default_setkeycode;
1871 dev_set_name(&dev->dev, "input%ld",
1872 (unsigned long) atomic_inc_return(&input_no) - 1);
1874 error = device_add(&dev->dev);
1878 path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
1879 pr_info("%s as %s\n",
1880 dev->name ? dev->name : "Unspecified device",
1881 path ? path : "N/A");
1884 error = mutex_lock_interruptible(&input_mutex);
1886 device_del(&dev->dev);
1890 list_add_tail(&dev->node, &input_dev_list);
1892 list_for_each_entry(handler, &input_handler_list, node)
1893 input_attach_handler(dev, handler);
1895 input_wakeup_procfs_readers();
1897 mutex_unlock(&input_mutex);
1901 EXPORT_SYMBOL(input_register_device);
1904 * input_unregister_device - unregister previously registered device
1905 * @dev: device to be unregistered
1907 * This function unregisters an input device. Once device is unregistered
1908 * the caller should not try to access it as it may get freed at any moment.
1910 void input_unregister_device(struct input_dev *dev)
1912 struct input_handle *handle, *next;
1914 input_disconnect_device(dev);
1916 mutex_lock(&input_mutex);
1918 list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
1919 handle->handler->disconnect(handle);
1920 WARN_ON(!list_empty(&dev->h_list));
1922 del_timer_sync(&dev->timer);
1923 list_del_init(&dev->node);
1925 input_wakeup_procfs_readers();
1927 mutex_unlock(&input_mutex);
1929 device_unregister(&dev->dev);
1931 EXPORT_SYMBOL(input_unregister_device);
1934 * input_register_handler - register a new input handler
1935 * @handler: handler to be registered
1937 * This function registers a new input handler (interface) for input
1938 * devices in the system and attaches it to all input devices that
1939 * are compatible with the handler.
1941 int input_register_handler(struct input_handler *handler)
1943 struct input_dev *dev;
1946 retval = mutex_lock_interruptible(&input_mutex);
1950 INIT_LIST_HEAD(&handler->h_list);
1952 if (handler->fops != NULL) {
1953 if (input_table[handler->minor >> 5]) {
1957 input_table[handler->minor >> 5] = handler;
1960 list_add_tail(&handler->node, &input_handler_list);
1962 list_for_each_entry(dev, &input_dev_list, node)
1963 input_attach_handler(dev, handler);
1965 input_wakeup_procfs_readers();
1968 mutex_unlock(&input_mutex);
1971 EXPORT_SYMBOL(input_register_handler);
1974 * input_unregister_handler - unregisters an input handler
1975 * @handler: handler to be unregistered
1977 * This function disconnects a handler from its input devices and
1978 * removes it from lists of known handlers.
1980 void input_unregister_handler(struct input_handler *handler)
1982 struct input_handle *handle, *next;
1984 mutex_lock(&input_mutex);
1986 list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
1987 handler->disconnect(handle);
1988 WARN_ON(!list_empty(&handler->h_list));
1990 list_del_init(&handler->node);
1992 if (handler->fops != NULL)
1993 input_table[handler->minor >> 5] = NULL;
1995 input_wakeup_procfs_readers();
1997 mutex_unlock(&input_mutex);
1999 EXPORT_SYMBOL(input_unregister_handler);
2002 * input_handler_for_each_handle - handle iterator
2003 * @handler: input handler to iterate
2004 * @data: data for the callback
2005 * @fn: function to be called for each handle
2007 * Iterate over @bus's list of devices, and call @fn for each, passing
2008 * it @data and stop when @fn returns a non-zero value. The function is
2009 * using RCU to traverse the list and therefore may be usind in atonic
2010 * contexts. The @fn callback is invoked from RCU critical section and
2011 * thus must not sleep.
2013 int input_handler_for_each_handle(struct input_handler *handler, void *data,
2014 int (*fn)(struct input_handle *, void *))
2016 struct input_handle *handle;
2021 list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
2022 retval = fn(handle, data);
2031 EXPORT_SYMBOL(input_handler_for_each_handle);
2034 * input_register_handle - register a new input handle
2035 * @handle: handle to register
2037 * This function puts a new input handle onto device's
2038 * and handler's lists so that events can flow through
2039 * it once it is opened using input_open_device().
2041 * This function is supposed to be called from handler's
2044 int input_register_handle(struct input_handle *handle)
2046 struct input_handler *handler = handle->handler;
2047 struct input_dev *dev = handle->dev;
2051 * We take dev->mutex here to prevent race with
2052 * input_release_device().
2054 error = mutex_lock_interruptible(&dev->mutex);
2059 * Filters go to the head of the list, normal handlers
2062 if (handler->filter)
2063 list_add_rcu(&handle->d_node, &dev->h_list);
2065 list_add_tail_rcu(&handle->d_node, &dev->h_list);
2067 mutex_unlock(&dev->mutex);
2070 * Since we are supposed to be called from ->connect()
2071 * which is mutually exclusive with ->disconnect()
2072 * we can't be racing with input_unregister_handle()
2073 * and so separate lock is not needed here.
2075 list_add_tail_rcu(&handle->h_node, &handler->h_list);
2078 handler->start(handle);
2082 EXPORT_SYMBOL(input_register_handle);
2085 * input_unregister_handle - unregister an input handle
2086 * @handle: handle to unregister
2088 * This function removes input handle from device's
2089 * and handler's lists.
2091 * This function is supposed to be called from handler's
2092 * disconnect() method.
2094 void input_unregister_handle(struct input_handle *handle)
2096 struct input_dev *dev = handle->dev;
2098 list_del_rcu(&handle->h_node);
2101 * Take dev->mutex to prevent race with input_release_device().
2103 mutex_lock(&dev->mutex);
2104 list_del_rcu(&handle->d_node);
2105 mutex_unlock(&dev->mutex);
2109 EXPORT_SYMBOL(input_unregister_handle);
2111 static int input_open_file(struct inode *inode, struct file *file)
2113 struct input_handler *handler;
2114 const struct file_operations *old_fops, *new_fops = NULL;
2117 err = mutex_lock_interruptible(&input_mutex);
2121 /* No load-on-demand here? */
2122 handler = input_table[iminor(inode) >> 5];
2124 new_fops = fops_get(handler->fops);
2126 mutex_unlock(&input_mutex);
2129 * That's _really_ odd. Usually NULL ->open means "nothing special",
2130 * not "no device". Oh, well...
2132 if (!new_fops || !new_fops->open) {
2138 old_fops = file->f_op;
2139 file->f_op = new_fops;
2141 err = new_fops->open(inode, file);
2143 fops_put(file->f_op);
2144 file->f_op = fops_get(old_fops);
2151 static const struct file_operations input_fops = {
2152 .owner = THIS_MODULE,
2153 .open = input_open_file,
2154 .llseek = noop_llseek,
2157 static int __init input_init(void)
2161 err = class_register(&input_class);
2163 pr_err("unable to register input_dev class\n");
2167 err = input_proc_init();
2171 err = register_chrdev(INPUT_MAJOR, "input", &input_fops);
2173 pr_err("unable to register char major %d", INPUT_MAJOR);
2179 fail2: input_proc_exit();
2180 fail1: class_unregister(&input_class);
2184 static void __exit input_exit(void)
2187 unregister_chrdev(INPUT_MAJOR, "input");
2188 class_unregister(&input_class);
2191 subsys_initcall(input_init);
2192 module_exit(input_exit);