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/module.h>
22 #include <linux/init.h>
23 #include <linux/input/mt.h>
24 #include <linux/major.h>
25 #include <linux/device.h>
26 #include <linux/cdev.h>
27 #include "input-compat.h"
31 struct input_handle handle
;
32 wait_queue_head_t wait
;
33 struct evdev_client __rcu
*grab
;
34 struct list_head client_list
;
35 spinlock_t client_lock
; /* protects client_list */
45 unsigned int packet_head
; /* [future] position of the first element of next packet */
46 spinlock_t buffer_lock
; /* protects access to buffer, head and tail */
47 struct fasync_struct
*fasync
;
49 struct list_head node
;
53 struct input_event buffer
[];
56 /* flush queued events of type @type, caller must hold client->buffer_lock */
57 static void __evdev_flush_queue(struct evdev_client
*client
, unsigned int type
)
59 unsigned int i
, head
, num
;
60 unsigned int mask
= client
->bufsize
- 1;
62 struct input_event
*ev
;
64 BUG_ON(type
== EV_SYN
);
67 client
->packet_head
= client
->tail
;
69 /* init to 1 so a leading SYN_REPORT will not be dropped */
72 for (i
= client
->tail
; i
!= client
->head
; i
= (i
+ 1) & mask
) {
73 ev
= &client
->buffer
[i
];
74 is_report
= ev
->type
== EV_SYN
&& ev
->code
== SYN_REPORT
;
76 if (ev
->type
== type
) {
77 /* drop matched entry */
79 } else if (is_report
&& !num
) {
80 /* drop empty SYN_REPORT groups */
82 } else if (head
!= i
) {
83 /* move entry to fill the gap */
84 client
->buffer
[head
].time
= ev
->time
;
85 client
->buffer
[head
].type
= ev
->type
;
86 client
->buffer
[head
].code
= ev
->code
;
87 client
->buffer
[head
].value
= ev
->value
;
91 head
= (head
+ 1) & mask
;
95 client
->packet_head
= head
;
102 /* queue SYN_DROPPED event */
103 static void evdev_queue_syn_dropped(struct evdev_client
*client
)
106 struct input_event ev
;
110 if (client
->clkid
!= CLOCK_MONOTONIC
)
111 time
= ktime_sub(time
, ktime_get_monotonic_offset());
113 ev
.time
= ktime_to_timeval(time
);
115 ev
.code
= SYN_DROPPED
;
118 spin_lock_irqsave(&client
->buffer_lock
, flags
);
120 client
->buffer
[client
->head
++] = ev
;
121 client
->head
&= client
->bufsize
- 1;
123 if (unlikely(client
->head
== client
->tail
)) {
124 /* drop queue but keep our SYN_DROPPED event */
125 client
->tail
= (client
->head
- 1) & (client
->bufsize
- 1);
126 client
->packet_head
= client
->tail
;
129 spin_unlock_irqrestore(&client
->buffer_lock
, flags
);
132 static void __pass_event(struct evdev_client
*client
,
133 const struct input_event
*event
)
135 client
->buffer
[client
->head
++] = *event
;
136 client
->head
&= client
->bufsize
- 1;
138 if (unlikely(client
->head
== client
->tail
)) {
140 * This effectively "drops" all unconsumed events, leaving
141 * EV_SYN/SYN_DROPPED plus the newest event in the queue.
143 client
->tail
= (client
->head
- 2) & (client
->bufsize
- 1);
145 client
->buffer
[client
->tail
].time
= event
->time
;
146 client
->buffer
[client
->tail
].type
= EV_SYN
;
147 client
->buffer
[client
->tail
].code
= SYN_DROPPED
;
148 client
->buffer
[client
->tail
].value
= 0;
150 client
->packet_head
= client
->tail
;
153 if (event
->type
== EV_SYN
&& event
->code
== SYN_REPORT
) {
154 client
->packet_head
= client
->head
;
155 kill_fasync(&client
->fasync
, SIGIO
, POLL_IN
);
159 static void evdev_pass_values(struct evdev_client
*client
,
160 const struct input_value
*vals
, unsigned int count
,
161 ktime_t mono
, ktime_t real
)
163 struct evdev
*evdev
= client
->evdev
;
164 const struct input_value
*v
;
165 struct input_event event
;
171 event
.time
= ktime_to_timeval(client
->clkid
== CLOCK_MONOTONIC
?
174 /* Interrupts are disabled, just acquire the lock. */
175 spin_lock(&client
->buffer_lock
);
177 for (v
= vals
; v
!= vals
+ count
; v
++) {
178 event
.type
= v
->type
;
179 event
.code
= v
->code
;
180 event
.value
= v
->value
;
181 __pass_event(client
, &event
);
182 if (v
->type
== EV_SYN
&& v
->code
== SYN_REPORT
)
186 spin_unlock(&client
->buffer_lock
);
189 wake_up_interruptible(&evdev
->wait
);
193 * Pass incoming events to all connected clients.
195 static void evdev_events(struct input_handle
*handle
,
196 const struct input_value
*vals
, unsigned int count
)
198 struct evdev
*evdev
= handle
->private;
199 struct evdev_client
*client
;
200 ktime_t time_mono
, time_real
;
202 time_mono
= ktime_get();
203 time_real
= ktime_sub(time_mono
, ktime_get_monotonic_offset());
207 client
= rcu_dereference(evdev
->grab
);
210 evdev_pass_values(client
, vals
, count
, time_mono
, time_real
);
212 list_for_each_entry_rcu(client
, &evdev
->client_list
, node
)
213 evdev_pass_values(client
, vals
, count
,
214 time_mono
, time_real
);
220 * Pass incoming event to all connected clients.
222 static void evdev_event(struct input_handle
*handle
,
223 unsigned int type
, unsigned int code
, int value
)
225 struct input_value vals
[] = { { type
, code
, value
} };
227 evdev_events(handle
, vals
, 1);
230 static int evdev_fasync(int fd
, struct file
*file
, int on
)
232 struct evdev_client
*client
= file
->private_data
;
234 return fasync_helper(fd
, file
, on
, &client
->fasync
);
237 static int evdev_flush(struct file
*file
, fl_owner_t id
)
239 struct evdev_client
*client
= file
->private_data
;
240 struct evdev
*evdev
= client
->evdev
;
243 retval
= mutex_lock_interruptible(&evdev
->mutex
);
247 if (!evdev
->exist
|| client
->revoked
)
250 retval
= input_flush_device(&evdev
->handle
, file
);
252 mutex_unlock(&evdev
->mutex
);
256 static void evdev_free(struct device
*dev
)
258 struct evdev
*evdev
= container_of(dev
, struct evdev
, dev
);
260 input_put_device(evdev
->handle
.dev
);
265 * Grabs an event device (along with underlying input device).
266 * This function is called with evdev->mutex taken.
268 static int evdev_grab(struct evdev
*evdev
, struct evdev_client
*client
)
275 error
= input_grab_device(&evdev
->handle
);
279 rcu_assign_pointer(evdev
->grab
, client
);
284 static int evdev_ungrab(struct evdev
*evdev
, struct evdev_client
*client
)
286 struct evdev_client
*grab
= rcu_dereference_protected(evdev
->grab
,
287 lockdep_is_held(&evdev
->mutex
));
292 rcu_assign_pointer(evdev
->grab
, NULL
);
294 input_release_device(&evdev
->handle
);
299 static void evdev_attach_client(struct evdev
*evdev
,
300 struct evdev_client
*client
)
302 spin_lock(&evdev
->client_lock
);
303 list_add_tail_rcu(&client
->node
, &evdev
->client_list
);
304 spin_unlock(&evdev
->client_lock
);
307 static void evdev_detach_client(struct evdev
*evdev
,
308 struct evdev_client
*client
)
310 spin_lock(&evdev
->client_lock
);
311 list_del_rcu(&client
->node
);
312 spin_unlock(&evdev
->client_lock
);
316 static int evdev_open_device(struct evdev
*evdev
)
320 retval
= mutex_lock_interruptible(&evdev
->mutex
);
326 else if (!evdev
->open
++) {
327 retval
= input_open_device(&evdev
->handle
);
332 mutex_unlock(&evdev
->mutex
);
336 static void evdev_close_device(struct evdev
*evdev
)
338 mutex_lock(&evdev
->mutex
);
340 if (evdev
->exist
&& !--evdev
->open
)
341 input_close_device(&evdev
->handle
);
343 mutex_unlock(&evdev
->mutex
);
347 * Wake up users waiting for IO so they can disconnect from
350 static void evdev_hangup(struct evdev
*evdev
)
352 struct evdev_client
*client
;
354 spin_lock(&evdev
->client_lock
);
355 list_for_each_entry(client
, &evdev
->client_list
, node
)
356 kill_fasync(&client
->fasync
, SIGIO
, POLL_HUP
);
357 spin_unlock(&evdev
->client_lock
);
359 wake_up_interruptible(&evdev
->wait
);
362 static int evdev_release(struct inode
*inode
, struct file
*file
)
364 struct evdev_client
*client
= file
->private_data
;
365 struct evdev
*evdev
= client
->evdev
;
367 mutex_lock(&evdev
->mutex
);
368 evdev_ungrab(evdev
, client
);
369 mutex_unlock(&evdev
->mutex
);
371 evdev_detach_client(evdev
, client
);
374 evdev_close_device(evdev
);
379 static unsigned int evdev_compute_buffer_size(struct input_dev
*dev
)
381 unsigned int n_events
=
382 max(dev
->hint_events_per_packet
* EVDEV_BUF_PACKETS
,
383 EVDEV_MIN_BUFFER_SIZE
);
385 return roundup_pow_of_two(n_events
);
388 static int evdev_open(struct inode
*inode
, struct file
*file
)
390 struct evdev
*evdev
= container_of(inode
->i_cdev
, struct evdev
, cdev
);
391 unsigned int bufsize
= evdev_compute_buffer_size(evdev
->handle
.dev
);
392 struct evdev_client
*client
;
395 client
= kzalloc(sizeof(struct evdev_client
) +
396 bufsize
* sizeof(struct input_event
),
401 client
->bufsize
= bufsize
;
402 spin_lock_init(&client
->buffer_lock
);
403 client
->evdev
= evdev
;
404 evdev_attach_client(evdev
, client
);
406 error
= evdev_open_device(evdev
);
408 goto err_free_client
;
410 file
->private_data
= client
;
411 nonseekable_open(inode
, file
);
416 evdev_detach_client(evdev
, client
);
421 static ssize_t
evdev_write(struct file
*file
, const char __user
*buffer
,
422 size_t count
, loff_t
*ppos
)
424 struct evdev_client
*client
= file
->private_data
;
425 struct evdev
*evdev
= client
->evdev
;
426 struct input_event event
;
429 if (count
!= 0 && count
< input_event_size())
432 retval
= mutex_lock_interruptible(&evdev
->mutex
);
436 if (!evdev
->exist
|| client
->revoked
) {
441 while (retval
+ input_event_size() <= count
) {
443 if (input_event_from_user(buffer
+ retval
, &event
)) {
447 retval
+= input_event_size();
449 input_inject_event(&evdev
->handle
,
450 event
.type
, event
.code
, event
.value
);
454 mutex_unlock(&evdev
->mutex
);
458 static int evdev_fetch_next_event(struct evdev_client
*client
,
459 struct input_event
*event
)
463 spin_lock_irq(&client
->buffer_lock
);
465 have_event
= client
->packet_head
!= client
->tail
;
467 *event
= client
->buffer
[client
->tail
++];
468 client
->tail
&= client
->bufsize
- 1;
471 spin_unlock_irq(&client
->buffer_lock
);
476 static ssize_t
evdev_read(struct file
*file
, char __user
*buffer
,
477 size_t count
, loff_t
*ppos
)
479 struct evdev_client
*client
= file
->private_data
;
480 struct evdev
*evdev
= client
->evdev
;
481 struct input_event event
;
485 if (count
!= 0 && count
< input_event_size())
489 if (!evdev
->exist
|| client
->revoked
)
492 if (client
->packet_head
== client
->tail
&&
493 (file
->f_flags
& O_NONBLOCK
))
497 * count == 0 is special - no IO is done but we check
498 * for error conditions (see above).
503 while (read
+ input_event_size() <= count
&&
504 evdev_fetch_next_event(client
, &event
)) {
506 if (input_event_to_user(buffer
+ read
, &event
))
509 read
+= input_event_size();
515 if (!(file
->f_flags
& O_NONBLOCK
)) {
516 error
= wait_event_interruptible(evdev
->wait
,
517 client
->packet_head
!= client
->tail
||
518 !evdev
->exist
|| client
->revoked
);
527 /* No kernel lock - fine */
528 static unsigned int evdev_poll(struct file
*file
, poll_table
*wait
)
530 struct evdev_client
*client
= file
->private_data
;
531 struct evdev
*evdev
= client
->evdev
;
534 poll_wait(file
, &evdev
->wait
, wait
);
536 if (evdev
->exist
&& !client
->revoked
)
537 mask
= POLLOUT
| POLLWRNORM
;
539 mask
= POLLHUP
| POLLERR
;
541 if (client
->packet_head
!= client
->tail
)
542 mask
|= POLLIN
| POLLRDNORM
;
549 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
550 #define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
553 static int bits_to_user(unsigned long *bits
, unsigned int maxbit
,
554 unsigned int maxlen
, void __user
*p
, int compat
)
559 len
= BITS_TO_LONGS_COMPAT(maxbit
) * sizeof(compat_long_t
);
563 for (i
= 0; i
< len
/ sizeof(compat_long_t
); i
++)
564 if (copy_to_user((compat_long_t __user
*) p
+ i
,
565 (compat_long_t
*) bits
+
566 i
+ 1 - ((i
% 2) << 1),
567 sizeof(compat_long_t
)))
570 len
= BITS_TO_LONGS(maxbit
) * sizeof(long);
574 if (copy_to_user(p
, bits
, len
))
581 static int bits_to_user(unsigned long *bits
, unsigned int maxbit
,
582 unsigned int maxlen
, void __user
*p
, int compat
)
585 BITS_TO_LONGS_COMPAT(maxbit
) * sizeof(compat_long_t
) :
586 BITS_TO_LONGS(maxbit
) * sizeof(long);
591 return copy_to_user(p
, bits
, len
) ? -EFAULT
: len
;
593 #endif /* __BIG_ENDIAN */
597 static int bits_to_user(unsigned long *bits
, unsigned int maxbit
,
598 unsigned int maxlen
, void __user
*p
, int compat
)
600 int len
= BITS_TO_LONGS(maxbit
) * sizeof(long);
605 return copy_to_user(p
, bits
, len
) ? -EFAULT
: len
;
608 #endif /* CONFIG_COMPAT */
610 static int str_to_user(const char *str
, unsigned int maxlen
, void __user
*p
)
617 len
= strlen(str
) + 1;
621 return copy_to_user(p
, str
, len
) ? -EFAULT
: len
;
624 #define OLD_KEY_MAX 0x1ff
625 static int handle_eviocgbit(struct input_dev
*dev
,
626 unsigned int type
, unsigned int size
,
627 void __user
*p
, int compat_mode
)
629 static unsigned long keymax_warn_time
;
635 case 0: bits
= dev
->evbit
; len
= EV_MAX
; break;
636 case EV_KEY
: bits
= dev
->keybit
; len
= KEY_MAX
; break;
637 case EV_REL
: bits
= dev
->relbit
; len
= REL_MAX
; break;
638 case EV_ABS
: bits
= dev
->absbit
; len
= ABS_MAX
; break;
639 case EV_MSC
: bits
= dev
->mscbit
; len
= MSC_MAX
; break;
640 case EV_LED
: bits
= dev
->ledbit
; len
= LED_MAX
; break;
641 case EV_SND
: bits
= dev
->sndbit
; len
= SND_MAX
; break;
642 case EV_FF
: bits
= dev
->ffbit
; len
= FF_MAX
; break;
643 case EV_SW
: bits
= dev
->swbit
; len
= SW_MAX
; break;
644 default: return -EINVAL
;
648 * Work around bugs in userspace programs that like to do
649 * EVIOCGBIT(EV_KEY, KEY_MAX) and not realize that 'len'
650 * should be in bytes, not in bits.
652 if (type
== EV_KEY
&& size
== OLD_KEY_MAX
) {
654 if (printk_timed_ratelimit(&keymax_warn_time
, 10 * 1000))
655 pr_warning("(EVIOCGBIT): Suspicious buffer size %u, "
656 "limiting output to %zu bytes. See "
657 "http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n",
659 BITS_TO_LONGS(OLD_KEY_MAX
) * sizeof(long));
662 return bits_to_user(bits
, len
, size
, p
, compat_mode
);
666 static int evdev_handle_get_keycode(struct input_dev
*dev
, void __user
*p
)
668 struct input_keymap_entry ke
= {
669 .len
= sizeof(unsigned int),
672 int __user
*ip
= (int __user
*)p
;
676 if (copy_from_user(ke
.scancode
, p
, sizeof(unsigned int)))
679 error
= input_get_keycode(dev
, &ke
);
683 if (put_user(ke
.keycode
, ip
+ 1))
689 static int evdev_handle_get_keycode_v2(struct input_dev
*dev
, void __user
*p
)
691 struct input_keymap_entry ke
;
694 if (copy_from_user(&ke
, p
, sizeof(ke
)))
697 error
= input_get_keycode(dev
, &ke
);
701 if (copy_to_user(p
, &ke
, sizeof(ke
)))
707 static int evdev_handle_set_keycode(struct input_dev
*dev
, void __user
*p
)
709 struct input_keymap_entry ke
= {
710 .len
= sizeof(unsigned int),
713 int __user
*ip
= (int __user
*)p
;
715 if (copy_from_user(ke
.scancode
, p
, sizeof(unsigned int)))
718 if (get_user(ke
.keycode
, ip
+ 1))
721 return input_set_keycode(dev
, &ke
);
724 static int evdev_handle_set_keycode_v2(struct input_dev
*dev
, void __user
*p
)
726 struct input_keymap_entry ke
;
728 if (copy_from_user(&ke
, p
, sizeof(ke
)))
731 if (ke
.len
> sizeof(ke
.scancode
))
734 return input_set_keycode(dev
, &ke
);
738 * If we transfer state to the user, we should flush all pending events
739 * of the same type from the client's queue. Otherwise, they might end up
740 * with duplicate events, which can screw up client's state tracking.
741 * If bits_to_user fails after flushing the queue, we queue a SYN_DROPPED
742 * event so user-space will notice missing events.
745 * We need to take event_lock before buffer_lock to avoid dead-locks. But we
746 * need the even_lock only to guarantee consistent state. We can safely release
747 * it while flushing the queue. This allows input-core to handle filters while
748 * we flush the queue.
750 static int evdev_handle_get_val(struct evdev_client
*client
,
751 struct input_dev
*dev
, unsigned int type
,
752 unsigned long *bits
, unsigned int max
,
753 unsigned int size
, void __user
*p
, int compat
)
758 mem
= kmalloc(sizeof(unsigned long) * max
, GFP_KERNEL
);
762 spin_lock_irq(&dev
->event_lock
);
763 spin_lock(&client
->buffer_lock
);
765 memcpy(mem
, bits
, sizeof(unsigned long) * max
);
767 spin_unlock(&dev
->event_lock
);
769 __evdev_flush_queue(client
, type
);
771 spin_unlock_irq(&client
->buffer_lock
);
773 ret
= bits_to_user(mem
, max
, size
, p
, compat
);
775 evdev_queue_syn_dropped(client
);
782 static int evdev_handle_mt_request(struct input_dev
*dev
,
786 const struct input_mt
*mt
= dev
->mt
;
791 if (get_user(code
, &ip
[0]))
793 if (!mt
|| !input_is_mt_value(code
))
796 max_slots
= (size
- sizeof(__u32
)) / sizeof(__s32
);
797 for (i
= 0; i
< mt
->num_slots
&& i
< max_slots
; i
++) {
798 int value
= input_mt_get_value(&mt
->slots
[i
], code
);
799 if (put_user(value
, &ip
[1 + i
]))
806 static int evdev_revoke(struct evdev
*evdev
, struct evdev_client
*client
,
809 client
->revoked
= true;
810 evdev_ungrab(evdev
, client
);
811 input_flush_device(&evdev
->handle
, file
);
812 wake_up_interruptible(&evdev
->wait
);
817 static long evdev_do_ioctl(struct file
*file
, unsigned int cmd
,
818 void __user
*p
, int compat_mode
)
820 struct evdev_client
*client
= file
->private_data
;
821 struct evdev
*evdev
= client
->evdev
;
822 struct input_dev
*dev
= evdev
->handle
.dev
;
823 struct input_absinfo abs
;
824 struct ff_effect effect
;
825 int __user
*ip
= (int __user
*)p
;
826 unsigned int i
, t
, u
, v
;
830 /* First we check for fixed-length commands */
834 return put_user(EV_VERSION
, ip
);
837 if (copy_to_user(p
, &dev
->id
, sizeof(struct input_id
)))
842 if (!test_bit(EV_REP
, dev
->evbit
))
844 if (put_user(dev
->rep
[REP_DELAY
], ip
))
846 if (put_user(dev
->rep
[REP_PERIOD
], ip
+ 1))
851 if (!test_bit(EV_REP
, dev
->evbit
))
855 if (get_user(v
, ip
+ 1))
858 input_inject_event(&evdev
->handle
, EV_REP
, REP_DELAY
, u
);
859 input_inject_event(&evdev
->handle
, EV_REP
, REP_PERIOD
, v
);
864 return input_ff_erase(dev
, (int)(unsigned long) p
, file
);
867 i
= test_bit(EV_FF
, dev
->evbit
) ?
868 dev
->ff
->max_effects
: 0;
875 return evdev_grab(evdev
, client
);
877 return evdev_ungrab(evdev
, client
);
883 return evdev_revoke(evdev
, client
, file
);
886 if (copy_from_user(&i
, p
, sizeof(unsigned int)))
888 if (i
!= CLOCK_MONOTONIC
&& i
!= CLOCK_REALTIME
)
894 return evdev_handle_get_keycode(dev
, p
);
897 return evdev_handle_set_keycode(dev
, p
);
899 case EVIOCGKEYCODE_V2
:
900 return evdev_handle_get_keycode_v2(dev
, p
);
902 case EVIOCSKEYCODE_V2
:
903 return evdev_handle_set_keycode_v2(dev
, p
);
906 size
= _IOC_SIZE(cmd
);
908 /* Now check variable-length commands */
909 #define EVIOC_MASK_SIZE(nr) ((nr) & ~(_IOC_SIZEMASK << _IOC_SIZESHIFT))
910 switch (EVIOC_MASK_SIZE(cmd
)) {
913 return bits_to_user(dev
->propbit
, INPUT_PROP_MAX
,
914 size
, p
, compat_mode
);
916 case EVIOCGMTSLOTS(0):
917 return evdev_handle_mt_request(dev
, size
, ip
);
920 return evdev_handle_get_val(client
, dev
, EV_KEY
, dev
->key
,
921 KEY_MAX
, size
, p
, compat_mode
);
924 return evdev_handle_get_val(client
, dev
, EV_LED
, dev
->led
,
925 LED_MAX
, size
, p
, compat_mode
);
928 return evdev_handle_get_val(client
, dev
, EV_SND
, dev
->snd
,
929 SND_MAX
, size
, p
, compat_mode
);
932 return evdev_handle_get_val(client
, dev
, EV_SW
, dev
->sw
,
933 SW_MAX
, size
, p
, compat_mode
);
936 return str_to_user(dev
->name
, size
, p
);
939 return str_to_user(dev
->phys
, size
, p
);
942 return str_to_user(dev
->uniq
, size
, p
);
944 case EVIOC_MASK_SIZE(EVIOCSFF
):
945 if (input_ff_effect_from_user(p
, size
, &effect
))
948 error
= input_ff_upload(dev
, &effect
, file
);
950 if (put_user(effect
.id
, &(((struct ff_effect __user
*)p
)->id
)))
956 /* Multi-number variable-length handlers */
957 if (_IOC_TYPE(cmd
) != 'E')
960 if (_IOC_DIR(cmd
) == _IOC_READ
) {
962 if ((_IOC_NR(cmd
) & ~EV_MAX
) == _IOC_NR(EVIOCGBIT(0, 0)))
963 return handle_eviocgbit(dev
,
964 _IOC_NR(cmd
) & EV_MAX
, size
,
967 if ((_IOC_NR(cmd
) & ~ABS_MAX
) == _IOC_NR(EVIOCGABS(0))) {
972 t
= _IOC_NR(cmd
) & ABS_MAX
;
973 abs
= dev
->absinfo
[t
];
975 if (copy_to_user(p
, &abs
, min_t(size_t,
976 size
, sizeof(struct input_absinfo
))))
983 if (_IOC_DIR(cmd
) == _IOC_WRITE
) {
985 if ((_IOC_NR(cmd
) & ~ABS_MAX
) == _IOC_NR(EVIOCSABS(0))) {
990 t
= _IOC_NR(cmd
) & ABS_MAX
;
992 if (copy_from_user(&abs
, p
, min_t(size_t,
993 size
, sizeof(struct input_absinfo
))))
996 if (size
< sizeof(struct input_absinfo
))
999 /* We can't change number of reserved MT slots */
1000 if (t
== ABS_MT_SLOT
)
1004 * Take event lock to ensure that we are not
1005 * changing device parameters in the middle
1008 spin_lock_irq(&dev
->event_lock
);
1009 dev
->absinfo
[t
] = abs
;
1010 spin_unlock_irq(&dev
->event_lock
);
1019 static long evdev_ioctl_handler(struct file
*file
, unsigned int cmd
,
1020 void __user
*p
, int compat_mode
)
1022 struct evdev_client
*client
= file
->private_data
;
1023 struct evdev
*evdev
= client
->evdev
;
1026 retval
= mutex_lock_interruptible(&evdev
->mutex
);
1030 if (!evdev
->exist
|| client
->revoked
) {
1035 retval
= evdev_do_ioctl(file
, cmd
, p
, compat_mode
);
1038 mutex_unlock(&evdev
->mutex
);
1042 static long evdev_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1044 return evdev_ioctl_handler(file
, cmd
, (void __user
*)arg
, 0);
1047 #ifdef CONFIG_COMPAT
1048 static long evdev_ioctl_compat(struct file
*file
,
1049 unsigned int cmd
, unsigned long arg
)
1051 return evdev_ioctl_handler(file
, cmd
, compat_ptr(arg
), 1);
1055 static const struct file_operations evdev_fops
= {
1056 .owner
= THIS_MODULE
,
1058 .write
= evdev_write
,
1061 .release
= evdev_release
,
1062 .unlocked_ioctl
= evdev_ioctl
,
1063 #ifdef CONFIG_COMPAT
1064 .compat_ioctl
= evdev_ioctl_compat
,
1066 .fasync
= evdev_fasync
,
1067 .flush
= evdev_flush
,
1068 .llseek
= no_llseek
,
1072 * Mark device non-existent. This disables writes, ioctls and
1073 * prevents new users from opening the device. Already posted
1074 * blocking reads will stay, however new ones will fail.
1076 static void evdev_mark_dead(struct evdev
*evdev
)
1078 mutex_lock(&evdev
->mutex
);
1079 evdev
->exist
= false;
1080 mutex_unlock(&evdev
->mutex
);
1083 static void evdev_cleanup(struct evdev
*evdev
)
1085 struct input_handle
*handle
= &evdev
->handle
;
1087 evdev_mark_dead(evdev
);
1088 evdev_hangup(evdev
);
1090 cdev_del(&evdev
->cdev
);
1092 /* evdev is marked dead so no one else accesses evdev->open */
1094 input_flush_device(handle
, NULL
);
1095 input_close_device(handle
);
1100 * Create new evdev device. Note that input core serializes calls
1101 * to connect and disconnect.
1103 static int evdev_connect(struct input_handler
*handler
, struct input_dev
*dev
,
1104 const struct input_device_id
*id
)
1106 struct evdev
*evdev
;
1111 minor
= input_get_new_minor(EVDEV_MINOR_BASE
, EVDEV_MINORS
, true);
1114 pr_err("failed to reserve new minor: %d\n", error
);
1118 evdev
= kzalloc(sizeof(struct evdev
), GFP_KERNEL
);
1121 goto err_free_minor
;
1124 INIT_LIST_HEAD(&evdev
->client_list
);
1125 spin_lock_init(&evdev
->client_lock
);
1126 mutex_init(&evdev
->mutex
);
1127 init_waitqueue_head(&evdev
->wait
);
1128 evdev
->exist
= true;
1131 /* Normalize device number if it falls into legacy range */
1132 if (dev_no
< EVDEV_MINOR_BASE
+ EVDEV_MINORS
)
1133 dev_no
-= EVDEV_MINOR_BASE
;
1134 dev_set_name(&evdev
->dev
, "event%d", dev_no
);
1136 evdev
->handle
.dev
= input_get_device(dev
);
1137 evdev
->handle
.name
= dev_name(&evdev
->dev
);
1138 evdev
->handle
.handler
= handler
;
1139 evdev
->handle
.private = evdev
;
1141 evdev
->dev
.devt
= MKDEV(INPUT_MAJOR
, minor
);
1142 evdev
->dev
.class = &input_class
;
1143 evdev
->dev
.parent
= &dev
->dev
;
1144 evdev
->dev
.release
= evdev_free
;
1145 device_initialize(&evdev
->dev
);
1147 error
= input_register_handle(&evdev
->handle
);
1149 goto err_free_evdev
;
1151 cdev_init(&evdev
->cdev
, &evdev_fops
);
1152 evdev
->cdev
.kobj
.parent
= &evdev
->dev
.kobj
;
1153 error
= cdev_add(&evdev
->cdev
, evdev
->dev
.devt
, 1);
1155 goto err_unregister_handle
;
1157 error
= device_add(&evdev
->dev
);
1159 goto err_cleanup_evdev
;
1164 evdev_cleanup(evdev
);
1165 err_unregister_handle
:
1166 input_unregister_handle(&evdev
->handle
);
1168 put_device(&evdev
->dev
);
1170 input_free_minor(minor
);
1174 static void evdev_disconnect(struct input_handle
*handle
)
1176 struct evdev
*evdev
= handle
->private;
1178 device_del(&evdev
->dev
);
1179 evdev_cleanup(evdev
);
1180 input_free_minor(MINOR(evdev
->dev
.devt
));
1181 input_unregister_handle(handle
);
1182 put_device(&evdev
->dev
);
1185 static const struct input_device_id evdev_ids
[] = {
1186 { .driver_info
= 1 }, /* Matches all devices */
1187 { }, /* Terminating zero entry */
1190 MODULE_DEVICE_TABLE(input
, evdev_ids
);
1192 static struct input_handler evdev_handler
= {
1193 .event
= evdev_event
,
1194 .events
= evdev_events
,
1195 .connect
= evdev_connect
,
1196 .disconnect
= evdev_disconnect
,
1197 .legacy_minors
= true,
1198 .minor
= EVDEV_MINOR_BASE
,
1200 .id_table
= evdev_ids
,
1203 static int __init
evdev_init(void)
1205 return input_register_handler(&evdev_handler
);
1208 static void __exit
evdev_exit(void)
1210 input_unregister_handler(&evdev_handler
);
1213 module_init(evdev_init
);
1214 module_exit(evdev_exit
);
1216 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
1217 MODULE_DESCRIPTION("Input driver event char devices");
1218 MODULE_LICENSE("GPL");