2 * Event char devices, giving access to raw input device events.
4 * Copyright (c) 1999-2002 Vojtech Pavlik
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published by
8 * the Free Software Foundation.
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13 #define EVDEV_MINOR_BASE 64
14 #define EVDEV_MINORS 32
15 #define EVDEV_MIN_BUFFER_SIZE 64U
16 #define EVDEV_BUF_PACKETS 8
18 #include <linux/poll.h>
19 #include <linux/sched.h>
20 #include <linux/slab.h>
21 #include <linux/vmalloc.h>
23 #include <linux/module.h>
24 #include <linux/init.h>
25 #include <linux/input/mt.h>
26 #include <linux/major.h>
27 #include <linux/device.h>
28 #include <linux/cdev.h>
29 #include "input-compat.h"
31 enum evdev_clock_type {
40 struct input_handle handle;
41 wait_queue_head_t wait;
42 struct evdev_client __rcu *grab;
43 struct list_head client_list;
44 spinlock_t client_lock; /* protects client_list */
54 unsigned int packet_head; /* [future] position of the first element of next packet */
55 spinlock_t buffer_lock; /* protects access to buffer, head and tail */
56 struct fasync_struct *fasync;
58 struct list_head node;
61 unsigned long *evmasks[EV_CNT];
63 struct input_event buffer[];
66 static size_t evdev_get_mask_cnt(unsigned int type)
68 static const size_t counts[EV_CNT] = {
69 /* EV_SYN==0 is EV_CNT, _not_ SYN_CNT, see EVIOCGBIT */
81 return (type < EV_CNT) ? counts[type] : 0;
84 /* requires the buffer lock to be held */
85 static bool __evdev_is_filtered(struct evdev_client *client,
92 /* EV_SYN and unknown codes are never filtered */
93 if (type == EV_SYN || type >= EV_CNT)
96 /* first test whether the type is filtered */
97 mask = client->evmasks[0];
98 if (mask && !test_bit(type, mask))
101 /* unknown values are never filtered */
102 cnt = evdev_get_mask_cnt(type);
103 if (!cnt || code >= cnt)
106 mask = client->evmasks[type];
107 return mask && !test_bit(code, mask);
110 /* flush queued events of type @type, caller must hold client->buffer_lock */
111 static void __evdev_flush_queue(struct evdev_client *client, unsigned int type)
113 unsigned int i, head, num;
114 unsigned int mask = client->bufsize - 1;
116 struct input_event *ev;
118 BUG_ON(type == EV_SYN);
121 client->packet_head = client->tail;
123 /* init to 1 so a leading SYN_REPORT will not be dropped */
126 for (i = client->tail; i != client->head; i = (i + 1) & mask) {
127 ev = &client->buffer[i];
128 is_report = ev->type == EV_SYN && ev->code == SYN_REPORT;
130 if (ev->type == type) {
131 /* drop matched entry */
133 } else if (is_report && !num) {
134 /* drop empty SYN_REPORT groups */
136 } else if (head != i) {
137 /* move entry to fill the gap */
138 client->buffer[head].time = ev->time;
139 client->buffer[head].type = ev->type;
140 client->buffer[head].code = ev->code;
141 client->buffer[head].value = ev->value;
145 head = (head + 1) & mask;
149 client->packet_head = head;
156 static void __evdev_queue_syn_dropped(struct evdev_client *client)
158 struct input_event ev;
161 time = client->clk_type == EV_CLK_REAL ?
163 client->clk_type == EV_CLK_MONO ?
165 ktime_get_boottime();
167 ev.time = ktime_to_timeval(time);
169 ev.code = SYN_DROPPED;
172 client->buffer[client->head++] = ev;
173 client->head &= client->bufsize - 1;
175 if (unlikely(client->head == client->tail)) {
176 /* drop queue but keep our SYN_DROPPED event */
177 client->tail = (client->head - 1) & (client->bufsize - 1);
178 client->packet_head = client->tail;
182 static void evdev_queue_syn_dropped(struct evdev_client *client)
186 spin_lock_irqsave(&client->buffer_lock, flags);
187 __evdev_queue_syn_dropped(client);
188 spin_unlock_irqrestore(&client->buffer_lock, flags);
191 static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid)
195 if (client->clk_type == clkid)
201 client->clk_type = EV_CLK_REAL;
203 case CLOCK_MONOTONIC:
204 client->clk_type = EV_CLK_MONO;
207 client->clk_type = EV_CLK_BOOT;
214 * Flush pending events and queue SYN_DROPPED event,
215 * but only if the queue is not empty.
217 spin_lock_irqsave(&client->buffer_lock, flags);
219 if (client->head != client->tail) {
220 client->packet_head = client->head = client->tail;
221 __evdev_queue_syn_dropped(client);
224 spin_unlock_irqrestore(&client->buffer_lock, flags);
229 static void __pass_event(struct evdev_client *client,
230 const struct input_event *event)
232 client->buffer[client->head++] = *event;
233 client->head &= client->bufsize - 1;
235 if (unlikely(client->head == client->tail)) {
237 * This effectively "drops" all unconsumed events, leaving
238 * EV_SYN/SYN_DROPPED plus the newest event in the queue.
240 client->tail = (client->head - 2) & (client->bufsize - 1);
242 client->buffer[client->tail].time = event->time;
243 client->buffer[client->tail].type = EV_SYN;
244 client->buffer[client->tail].code = SYN_DROPPED;
245 client->buffer[client->tail].value = 0;
247 client->packet_head = client->tail;
250 if (event->type == EV_SYN && event->code == SYN_REPORT) {
251 client->packet_head = client->head;
252 kill_fasync(&client->fasync, SIGIO, POLL_IN);
256 static void evdev_pass_values(struct evdev_client *client,
257 const struct input_value *vals, unsigned int count,
260 struct evdev *evdev = client->evdev;
261 const struct input_value *v;
262 struct input_event event;
268 event.time = ktime_to_timeval(ev_time[client->clk_type]);
270 /* Interrupts are disabled, just acquire the lock. */
271 spin_lock(&client->buffer_lock);
273 for (v = vals; v != vals + count; v++) {
274 if (__evdev_is_filtered(client, v->type, v->code))
277 if (v->type == EV_SYN && v->code == SYN_REPORT) {
278 /* drop empty SYN_REPORT */
279 if (client->packet_head == client->head)
285 event.type = v->type;
286 event.code = v->code;
287 event.value = v->value;
288 __pass_event(client, &event);
291 spin_unlock(&client->buffer_lock);
294 wake_up_interruptible(&evdev->wait);
298 * Pass incoming events to all connected clients.
300 static void evdev_events(struct input_handle *handle,
301 const struct input_value *vals, unsigned int count)
303 struct evdev *evdev = handle->private;
304 struct evdev_client *client;
305 ktime_t ev_time[EV_CLK_MAX];
307 ev_time[EV_CLK_MONO] = ktime_get();
308 ev_time[EV_CLK_REAL] = ktime_mono_to_real(ev_time[EV_CLK_MONO]);
309 ev_time[EV_CLK_BOOT] = ktime_mono_to_any(ev_time[EV_CLK_MONO],
314 client = rcu_dereference(evdev->grab);
317 evdev_pass_values(client, vals, count, ev_time);
319 list_for_each_entry_rcu(client, &evdev->client_list, node)
320 evdev_pass_values(client, vals, count, ev_time);
326 * Pass incoming event to all connected clients.
328 static void evdev_event(struct input_handle *handle,
329 unsigned int type, unsigned int code, int value)
331 struct input_value vals[] = { { type, code, value } };
333 evdev_events(handle, vals, 1);
336 static int evdev_fasync(int fd, struct file *file, int on)
338 struct evdev_client *client = file->private_data;
340 return fasync_helper(fd, file, on, &client->fasync);
343 static int evdev_flush(struct file *file, fl_owner_t id)
345 struct evdev_client *client = file->private_data;
346 struct evdev *evdev = client->evdev;
348 mutex_lock(&evdev->mutex);
350 if (evdev->exist && !client->revoked)
351 input_flush_device(&evdev->handle, file);
353 mutex_unlock(&evdev->mutex);
357 static void evdev_free(struct device *dev)
359 struct evdev *evdev = container_of(dev, struct evdev, dev);
361 input_put_device(evdev->handle.dev);
366 * Grabs an event device (along with underlying input device).
367 * This function is called with evdev->mutex taken.
369 static int evdev_grab(struct evdev *evdev, struct evdev_client *client)
376 error = input_grab_device(&evdev->handle);
380 rcu_assign_pointer(evdev->grab, client);
385 static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client)
387 struct evdev_client *grab = rcu_dereference_protected(evdev->grab,
388 lockdep_is_held(&evdev->mutex));
393 rcu_assign_pointer(evdev->grab, NULL);
395 input_release_device(&evdev->handle);
400 static void evdev_attach_client(struct evdev *evdev,
401 struct evdev_client *client)
403 spin_lock(&evdev->client_lock);
404 list_add_tail_rcu(&client->node, &evdev->client_list);
405 spin_unlock(&evdev->client_lock);
408 static void evdev_detach_client(struct evdev *evdev,
409 struct evdev_client *client)
411 spin_lock(&evdev->client_lock);
412 list_del_rcu(&client->node);
413 spin_unlock(&evdev->client_lock);
417 static int evdev_open_device(struct evdev *evdev)
421 retval = mutex_lock_interruptible(&evdev->mutex);
427 else if (!evdev->open++) {
428 retval = input_open_device(&evdev->handle);
433 mutex_unlock(&evdev->mutex);
437 static void evdev_close_device(struct evdev *evdev)
439 mutex_lock(&evdev->mutex);
441 if (evdev->exist && !--evdev->open)
442 input_close_device(&evdev->handle);
444 mutex_unlock(&evdev->mutex);
448 * Wake up users waiting for IO so they can disconnect from
451 static void evdev_hangup(struct evdev *evdev)
453 struct evdev_client *client;
455 spin_lock(&evdev->client_lock);
456 list_for_each_entry(client, &evdev->client_list, node)
457 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
458 spin_unlock(&evdev->client_lock);
460 wake_up_interruptible(&evdev->wait);
463 static int evdev_release(struct inode *inode, struct file *file)
465 struct evdev_client *client = file->private_data;
466 struct evdev *evdev = client->evdev;
469 mutex_lock(&evdev->mutex);
470 evdev_ungrab(evdev, client);
471 mutex_unlock(&evdev->mutex);
473 evdev_detach_client(evdev, client);
475 for (i = 0; i < EV_CNT; ++i)
476 kfree(client->evmasks[i]);
480 evdev_close_device(evdev);
485 static unsigned int evdev_compute_buffer_size(struct input_dev *dev)
487 unsigned int n_events =
488 max(dev->hint_events_per_packet * EVDEV_BUF_PACKETS,
489 EVDEV_MIN_BUFFER_SIZE);
491 return roundup_pow_of_two(n_events);
494 static int evdev_open(struct inode *inode, struct file *file)
496 struct evdev *evdev = container_of(inode->i_cdev, struct evdev, cdev);
497 unsigned int bufsize = evdev_compute_buffer_size(evdev->handle.dev);
498 unsigned int size = sizeof(struct evdev_client) +
499 bufsize * sizeof(struct input_event);
500 struct evdev_client *client;
503 client = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
505 client = vzalloc(size);
509 client->bufsize = bufsize;
510 spin_lock_init(&client->buffer_lock);
511 client->evdev = evdev;
512 evdev_attach_client(evdev, client);
514 error = evdev_open_device(evdev);
516 goto err_free_client;
518 file->private_data = client;
519 nonseekable_open(inode, file);
524 evdev_detach_client(evdev, client);
529 static ssize_t evdev_write(struct file *file, const char __user *buffer,
530 size_t count, loff_t *ppos)
532 struct evdev_client *client = file->private_data;
533 struct evdev *evdev = client->evdev;
534 struct input_event event;
537 if (count != 0 && count < input_event_size())
540 retval = mutex_lock_interruptible(&evdev->mutex);
544 if (!evdev->exist || client->revoked) {
549 while (retval + input_event_size() <= count) {
551 if (input_event_from_user(buffer + retval, &event)) {
555 retval += input_event_size();
557 input_inject_event(&evdev->handle,
558 event.type, event.code, event.value);
562 mutex_unlock(&evdev->mutex);
566 static int evdev_fetch_next_event(struct evdev_client *client,
567 struct input_event *event)
571 spin_lock_irq(&client->buffer_lock);
573 have_event = client->packet_head != client->tail;
575 *event = client->buffer[client->tail++];
576 client->tail &= client->bufsize - 1;
579 spin_unlock_irq(&client->buffer_lock);
584 static ssize_t evdev_read(struct file *file, char __user *buffer,
585 size_t count, loff_t *ppos)
587 struct evdev_client *client = file->private_data;
588 struct evdev *evdev = client->evdev;
589 struct input_event event;
593 if (count != 0 && count < input_event_size())
597 if (!evdev->exist || client->revoked)
600 if (client->packet_head == client->tail &&
601 (file->f_flags & O_NONBLOCK))
605 * count == 0 is special - no IO is done but we check
606 * for error conditions (see above).
611 while (read + input_event_size() <= count &&
612 evdev_fetch_next_event(client, &event)) {
614 if (input_event_to_user(buffer + read, &event))
617 read += input_event_size();
623 if (!(file->f_flags & O_NONBLOCK)) {
624 error = wait_event_interruptible(evdev->wait,
625 client->packet_head != client->tail ||
626 !evdev->exist || client->revoked);
635 /* No kernel lock - fine */
636 static unsigned int evdev_poll(struct file *file, poll_table *wait)
638 struct evdev_client *client = file->private_data;
639 struct evdev *evdev = client->evdev;
642 poll_wait(file, &evdev->wait, wait);
644 if (evdev->exist && !client->revoked)
645 mask = POLLOUT | POLLWRNORM;
647 mask = POLLHUP | POLLERR;
649 if (client->packet_head != client->tail)
650 mask |= POLLIN | POLLRDNORM;
657 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
658 #define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
661 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
662 unsigned int maxlen, void __user *p, int compat)
667 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t);
671 for (i = 0; i < len / sizeof(compat_long_t); i++)
672 if (copy_to_user((compat_long_t __user *) p + i,
673 (compat_long_t *) bits +
674 i + 1 - ((i % 2) << 1),
675 sizeof(compat_long_t)))
678 len = BITS_TO_LONGS(maxbit) * sizeof(long);
682 if (copy_to_user(p, bits, len))
689 static int bits_from_user(unsigned long *bits, unsigned int maxbit,
690 unsigned int maxlen, const void __user *p, int compat)
695 if (maxlen % sizeof(compat_long_t))
698 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t);
702 for (i = 0; i < len / sizeof(compat_long_t); i++)
703 if (copy_from_user((compat_long_t *) bits +
704 i + 1 - ((i % 2) << 1),
705 (compat_long_t __user *) p + i,
706 sizeof(compat_long_t)))
709 *((compat_long_t *) bits + i - 1) = 0;
712 if (maxlen % sizeof(long))
715 len = BITS_TO_LONGS(maxbit) * sizeof(long);
719 if (copy_from_user(bits, p, len))
728 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
729 unsigned int maxlen, void __user *p, int compat)
732 BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) :
733 BITS_TO_LONGS(maxbit) * sizeof(long);
738 return copy_to_user(p, bits, len) ? -EFAULT : len;
741 static int bits_from_user(unsigned long *bits, unsigned int maxbit,
742 unsigned int maxlen, const void __user *p, int compat)
744 size_t chunk_size = compat ? sizeof(compat_long_t) : sizeof(long);
747 if (maxlen % chunk_size)
750 len = compat ? BITS_TO_LONGS_COMPAT(maxbit) : BITS_TO_LONGS(maxbit);
755 return copy_from_user(bits, p, len) ? -EFAULT : len;
758 #endif /* __BIG_ENDIAN */
762 static int bits_to_user(unsigned long *bits, unsigned int maxbit,
763 unsigned int maxlen, void __user *p, int compat)
765 int len = BITS_TO_LONGS(maxbit) * sizeof(long);
770 return copy_to_user(p, bits, len) ? -EFAULT : len;
773 static int bits_from_user(unsigned long *bits, unsigned int maxbit,
774 unsigned int maxlen, const void __user *p, int compat)
778 if (maxlen % sizeof(long))
781 len = BITS_TO_LONGS(maxbit) * sizeof(long);
785 return copy_from_user(bits, p, len) ? -EFAULT : len;
788 #endif /* CONFIG_COMPAT */
790 static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
797 len = strlen(str) + 1;
801 return copy_to_user(p, str, len) ? -EFAULT : len;
804 static int handle_eviocgbit(struct input_dev *dev,
805 unsigned int type, unsigned int size,
806 void __user *p, int compat_mode)
813 case 0: bits = dev->evbit; len = EV_MAX; break;
814 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
815 case EV_REL: bits = dev->relbit; len = REL_MAX; break;
816 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
817 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
818 case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
819 case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
820 case EV_FF: bits = dev->ffbit; len = FF_MAX; break;
821 case EV_SW: bits = dev->swbit; len = SW_MAX; break;
822 default: return -EINVAL;
825 return bits_to_user(bits, len, size, p, compat_mode);
828 static int evdev_handle_get_keycode(struct input_dev *dev, void __user *p)
830 struct input_keymap_entry ke = {
831 .len = sizeof(unsigned int),
834 int __user *ip = (int __user *)p;
838 if (copy_from_user(ke.scancode, p, sizeof(unsigned int)))
841 error = input_get_keycode(dev, &ke);
845 if (put_user(ke.keycode, ip + 1))
851 static int evdev_handle_get_keycode_v2(struct input_dev *dev, void __user *p)
853 struct input_keymap_entry ke;
856 if (copy_from_user(&ke, p, sizeof(ke)))
859 error = input_get_keycode(dev, &ke);
863 if (copy_to_user(p, &ke, sizeof(ke)))
869 static int evdev_handle_set_keycode(struct input_dev *dev, void __user *p)
871 struct input_keymap_entry ke = {
872 .len = sizeof(unsigned int),
875 int __user *ip = (int __user *)p;
877 if (copy_from_user(ke.scancode, p, sizeof(unsigned int)))
880 if (get_user(ke.keycode, ip + 1))
883 return input_set_keycode(dev, &ke);
886 static int evdev_handle_set_keycode_v2(struct input_dev *dev, void __user *p)
888 struct input_keymap_entry ke;
890 if (copy_from_user(&ke, p, sizeof(ke)))
893 if (ke.len > sizeof(ke.scancode))
896 return input_set_keycode(dev, &ke);
900 * If we transfer state to the user, we should flush all pending events
901 * of the same type from the client's queue. Otherwise, they might end up
902 * with duplicate events, which can screw up client's state tracking.
903 * If bits_to_user fails after flushing the queue, we queue a SYN_DROPPED
904 * event so user-space will notice missing events.
907 * We need to take event_lock before buffer_lock to avoid dead-locks. But we
908 * need the even_lock only to guarantee consistent state. We can safely release
909 * it while flushing the queue. This allows input-core to handle filters while
910 * we flush the queue.
912 static int evdev_handle_get_val(struct evdev_client *client,
913 struct input_dev *dev, unsigned int type,
914 unsigned long *bits, unsigned int maxbit,
915 unsigned int maxlen, void __user *p,
922 len = BITS_TO_LONGS(maxbit) * sizeof(unsigned long);
923 mem = kmalloc(len, GFP_KERNEL);
927 spin_lock_irq(&dev->event_lock);
928 spin_lock(&client->buffer_lock);
930 memcpy(mem, bits, len);
932 spin_unlock(&dev->event_lock);
934 __evdev_flush_queue(client, type);
936 spin_unlock_irq(&client->buffer_lock);
938 ret = bits_to_user(mem, maxbit, maxlen, p, compat);
940 evdev_queue_syn_dropped(client);
947 static int evdev_handle_mt_request(struct input_dev *dev,
951 const struct input_mt *mt = dev->mt;
956 if (get_user(code, &ip[0]))
958 if (!mt || !input_is_mt_value(code))
961 max_slots = (size - sizeof(__u32)) / sizeof(__s32);
962 for (i = 0; i < mt->num_slots && i < max_slots; i++) {
963 int value = input_mt_get_value(&mt->slots[i], code);
964 if (put_user(value, &ip[1 + i]))
971 static int evdev_revoke(struct evdev *evdev, struct evdev_client *client,
974 client->revoked = true;
975 evdev_ungrab(evdev, client);
976 input_flush_device(&evdev->handle, file);
977 wake_up_interruptible(&evdev->wait);
982 /* must be called with evdev-mutex held */
983 static int evdev_set_mask(struct evdev_client *client,
985 const void __user *codes,
989 unsigned long flags, *mask, *oldmask;
993 /* we allow unknown types and 'codes_size > size' for forward-compat */
994 cnt = evdev_get_mask_cnt(type);
998 mask = kcalloc(sizeof(unsigned long), BITS_TO_LONGS(cnt), GFP_KERNEL);
1002 error = bits_from_user(mask, cnt - 1, codes_size, codes, compat);
1008 spin_lock_irqsave(&client->buffer_lock, flags);
1009 oldmask = client->evmasks[type];
1010 client->evmasks[type] = mask;
1011 spin_unlock_irqrestore(&client->buffer_lock, flags);
1018 /* must be called with evdev-mutex held */
1019 static int evdev_get_mask(struct evdev_client *client,
1025 unsigned long *mask;
1026 size_t cnt, size, xfer_size;
1030 /* we allow unknown types and 'codes_size > size' for forward-compat */
1031 cnt = evdev_get_mask_cnt(type);
1032 size = sizeof(unsigned long) * BITS_TO_LONGS(cnt);
1033 xfer_size = min_t(size_t, codes_size, size);
1036 mask = client->evmasks[type];
1038 error = bits_to_user(mask, cnt - 1,
1039 xfer_size, codes, compat);
1043 /* fake mask with all bits set */
1044 for (i = 0; i < xfer_size; i++)
1045 if (put_user(0xffU, (u8 __user *)codes + i))
1050 if (xfer_size < codes_size)
1051 if (clear_user(codes + xfer_size, codes_size - xfer_size))
1057 static long evdev_do_ioctl(struct file *file, unsigned int cmd,
1058 void __user *p, int compat_mode)
1060 struct evdev_client *client = file->private_data;
1061 struct evdev *evdev = client->evdev;
1062 struct input_dev *dev = evdev->handle.dev;
1063 struct input_absinfo abs;
1064 struct input_mask mask;
1065 struct ff_effect effect;
1066 int __user *ip = (int __user *)p;
1067 unsigned int i, t, u, v;
1071 /* First we check for fixed-length commands */
1075 return put_user(EV_VERSION, ip);
1078 if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
1083 if (!test_bit(EV_REP, dev->evbit))
1085 if (put_user(dev->rep[REP_DELAY], ip))
1087 if (put_user(dev->rep[REP_PERIOD], ip + 1))
1092 if (!test_bit(EV_REP, dev->evbit))
1094 if (get_user(u, ip))
1096 if (get_user(v, ip + 1))
1099 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
1100 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
1105 return input_ff_erase(dev, (int)(unsigned long) p, file);
1108 i = test_bit(EV_FF, dev->evbit) ?
1109 dev->ff->max_effects : 0;
1110 if (put_user(i, ip))
1116 return evdev_grab(evdev, client);
1118 return evdev_ungrab(evdev, client);
1124 return evdev_revoke(evdev, client, file);
1127 void __user *codes_ptr;
1129 if (copy_from_user(&mask, p, sizeof(mask)))
1132 codes_ptr = (void __user *)(unsigned long)mask.codes_ptr;
1133 return evdev_get_mask(client,
1134 mask.type, codes_ptr, mask.codes_size,
1139 const void __user *codes_ptr;
1141 if (copy_from_user(&mask, p, sizeof(mask)))
1144 codes_ptr = (const void __user *)(unsigned long)mask.codes_ptr;
1145 return evdev_set_mask(client,
1146 mask.type, codes_ptr, mask.codes_size,
1151 if (copy_from_user(&i, p, sizeof(unsigned int)))
1154 return evdev_set_clk_type(client, i);
1157 return evdev_handle_get_keycode(dev, p);
1160 return evdev_handle_set_keycode(dev, p);
1162 case EVIOCGKEYCODE_V2:
1163 return evdev_handle_get_keycode_v2(dev, p);
1165 case EVIOCSKEYCODE_V2:
1166 return evdev_handle_set_keycode_v2(dev, p);
1169 size = _IOC_SIZE(cmd);
1171 /* Now check variable-length commands */
1172 #define EVIOC_MASK_SIZE(nr) ((nr) & ~(_IOC_SIZEMASK << _IOC_SIZESHIFT))
1173 switch (EVIOC_MASK_SIZE(cmd)) {
1176 return bits_to_user(dev->propbit, INPUT_PROP_MAX,
1177 size, p, compat_mode);
1179 case EVIOCGMTSLOTS(0):
1180 return evdev_handle_mt_request(dev, size, ip);
1183 return evdev_handle_get_val(client, dev, EV_KEY, dev->key,
1184 KEY_MAX, size, p, compat_mode);
1187 return evdev_handle_get_val(client, dev, EV_LED, dev->led,
1188 LED_MAX, size, p, compat_mode);
1191 return evdev_handle_get_val(client, dev, EV_SND, dev->snd,
1192 SND_MAX, size, p, compat_mode);
1195 return evdev_handle_get_val(client, dev, EV_SW, dev->sw,
1196 SW_MAX, size, p, compat_mode);
1199 return str_to_user(dev->name, size, p);
1202 return str_to_user(dev->phys, size, p);
1205 return str_to_user(dev->uniq, size, p);
1207 case EVIOC_MASK_SIZE(EVIOCSFF):
1208 if (input_ff_effect_from_user(p, size, &effect))
1211 error = input_ff_upload(dev, &effect, file);
1215 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
1221 /* Multi-number variable-length handlers */
1222 if (_IOC_TYPE(cmd) != 'E')
1225 if (_IOC_DIR(cmd) == _IOC_READ) {
1227 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0)))
1228 return handle_eviocgbit(dev,
1229 _IOC_NR(cmd) & EV_MAX, size,
1232 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
1237 t = _IOC_NR(cmd) & ABS_MAX;
1238 abs = dev->absinfo[t];
1240 if (copy_to_user(p, &abs, min_t(size_t,
1241 size, sizeof(struct input_absinfo))))
1248 if (_IOC_DIR(cmd) == _IOC_WRITE) {
1250 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
1255 t = _IOC_NR(cmd) & ABS_MAX;
1257 if (copy_from_user(&abs, p, min_t(size_t,
1258 size, sizeof(struct input_absinfo))))
1261 if (size < sizeof(struct input_absinfo))
1264 /* We can't change number of reserved MT slots */
1265 if (t == ABS_MT_SLOT)
1269 * Take event lock to ensure that we are not
1270 * changing device parameters in the middle
1273 spin_lock_irq(&dev->event_lock);
1274 dev->absinfo[t] = abs;
1275 spin_unlock_irq(&dev->event_lock);
1284 static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
1285 void __user *p, int compat_mode)
1287 struct evdev_client *client = file->private_data;
1288 struct evdev *evdev = client->evdev;
1291 retval = mutex_lock_interruptible(&evdev->mutex);
1295 if (!evdev->exist || client->revoked) {
1300 retval = evdev_do_ioctl(file, cmd, p, compat_mode);
1303 mutex_unlock(&evdev->mutex);
1307 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1309 return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
1312 #ifdef CONFIG_COMPAT
1313 static long evdev_ioctl_compat(struct file *file,
1314 unsigned int cmd, unsigned long arg)
1316 return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
1320 static const struct file_operations evdev_fops = {
1321 .owner = THIS_MODULE,
1323 .write = evdev_write,
1326 .release = evdev_release,
1327 .unlocked_ioctl = evdev_ioctl,
1328 #ifdef CONFIG_COMPAT
1329 .compat_ioctl = evdev_ioctl_compat,
1331 .fasync = evdev_fasync,
1332 .flush = evdev_flush,
1333 .llseek = no_llseek,
1337 * Mark device non-existent. This disables writes, ioctls and
1338 * prevents new users from opening the device. Already posted
1339 * blocking reads will stay, however new ones will fail.
1341 static void evdev_mark_dead(struct evdev *evdev)
1343 mutex_lock(&evdev->mutex);
1344 evdev->exist = false;
1345 mutex_unlock(&evdev->mutex);
1348 static void evdev_cleanup(struct evdev *evdev)
1350 struct input_handle *handle = &evdev->handle;
1352 evdev_mark_dead(evdev);
1353 evdev_hangup(evdev);
1355 cdev_del(&evdev->cdev);
1357 /* evdev is marked dead so no one else accesses evdev->open */
1359 input_flush_device(handle, NULL);
1360 input_close_device(handle);
1365 * Create new evdev device. Note that input core serializes calls
1366 * to connect and disconnect.
1368 static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
1369 const struct input_device_id *id)
1371 struct evdev *evdev;
1376 minor = input_get_new_minor(EVDEV_MINOR_BASE, EVDEV_MINORS, true);
1379 pr_err("failed to reserve new minor: %d\n", error);
1383 evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
1386 goto err_free_minor;
1389 INIT_LIST_HEAD(&evdev->client_list);
1390 spin_lock_init(&evdev->client_lock);
1391 mutex_init(&evdev->mutex);
1392 init_waitqueue_head(&evdev->wait);
1393 evdev->exist = true;
1396 /* Normalize device number if it falls into legacy range */
1397 if (dev_no < EVDEV_MINOR_BASE + EVDEV_MINORS)
1398 dev_no -= EVDEV_MINOR_BASE;
1399 dev_set_name(&evdev->dev, "event%d", dev_no);
1401 evdev->handle.dev = input_get_device(dev);
1402 evdev->handle.name = dev_name(&evdev->dev);
1403 evdev->handle.handler = handler;
1404 evdev->handle.private = evdev;
1406 evdev->dev.devt = MKDEV(INPUT_MAJOR, minor);
1407 evdev->dev.class = &input_class;
1408 evdev->dev.parent = &dev->dev;
1409 evdev->dev.release = evdev_free;
1410 device_initialize(&evdev->dev);
1412 error = input_register_handle(&evdev->handle);
1414 goto err_free_evdev;
1416 cdev_init(&evdev->cdev, &evdev_fops);
1417 evdev->cdev.kobj.parent = &evdev->dev.kobj;
1418 error = cdev_add(&evdev->cdev, evdev->dev.devt, 1);
1420 goto err_unregister_handle;
1422 error = device_add(&evdev->dev);
1424 goto err_cleanup_evdev;
1429 evdev_cleanup(evdev);
1430 err_unregister_handle:
1431 input_unregister_handle(&evdev->handle);
1433 put_device(&evdev->dev);
1435 input_free_minor(minor);
1439 static void evdev_disconnect(struct input_handle *handle)
1441 struct evdev *evdev = handle->private;
1443 device_del(&evdev->dev);
1444 evdev_cleanup(evdev);
1445 input_free_minor(MINOR(evdev->dev.devt));
1446 input_unregister_handle(handle);
1447 put_device(&evdev->dev);
1450 static const struct input_device_id evdev_ids[] = {
1451 { .driver_info = 1 }, /* Matches all devices */
1452 { }, /* Terminating zero entry */
1455 MODULE_DEVICE_TABLE(input, evdev_ids);
1457 static struct input_handler evdev_handler = {
1458 .event = evdev_event,
1459 .events = evdev_events,
1460 .connect = evdev_connect,
1461 .disconnect = evdev_disconnect,
1462 .legacy_minors = true,
1463 .minor = EVDEV_MINOR_BASE,
1465 .id_table = evdev_ids,
1468 static int __init evdev_init(void)
1470 return input_register_handler(&evdev_handler);
1473 static void __exit evdev_exit(void)
1475 input_unregister_handler(&evdev_handler);
1478 module_init(evdev_init);
1479 module_exit(evdev_exit);
1481 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
1482 MODULE_DESCRIPTION("Input driver event char devices");
1483 MODULE_LICENSE("GPL");