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"
33 struct input_handle handle
;
34 wait_queue_head_t wait
;
35 struct evdev_client __rcu
*grab
;
36 struct list_head client_list
;
37 spinlock_t client_lock
; /* protects client_list */
47 unsigned int packet_head
; /* [future] position of the first element of next packet */
48 spinlock_t buffer_lock
; /* protects access to buffer, head and tail */
49 struct fasync_struct
*fasync
;
51 struct list_head node
;
55 struct input_event buffer
[];
58 /* flush queued events of type @type, caller must hold client->buffer_lock */
59 static void __evdev_flush_queue(struct evdev_client
*client
, unsigned int type
)
61 unsigned int i
, head
, num
;
62 unsigned int mask
= client
->bufsize
- 1;
64 struct input_event
*ev
;
66 BUG_ON(type
== EV_SYN
);
69 client
->packet_head
= client
->tail
;
71 /* init to 1 so a leading SYN_REPORT will not be dropped */
74 for (i
= client
->tail
; i
!= client
->head
; i
= (i
+ 1) & mask
) {
75 ev
= &client
->buffer
[i
];
76 is_report
= ev
->type
== EV_SYN
&& ev
->code
== SYN_REPORT
;
78 if (ev
->type
== type
) {
79 /* drop matched entry */
81 } else if (is_report
&& !num
) {
82 /* drop empty SYN_REPORT groups */
84 } else if (head
!= i
) {
85 /* move entry to fill the gap */
86 client
->buffer
[head
].time
= ev
->time
;
87 client
->buffer
[head
].type
= ev
->type
;
88 client
->buffer
[head
].code
= ev
->code
;
89 client
->buffer
[head
].value
= ev
->value
;
93 head
= (head
+ 1) & mask
;
97 client
->packet_head
= head
;
104 /* queue SYN_DROPPED event */
105 static void evdev_queue_syn_dropped(struct evdev_client
*client
)
108 struct input_event ev
;
111 time
= (client
->clkid
== CLOCK_MONOTONIC
) ?
112 ktime_get() : ktime_get_real();
114 ev
.time
= ktime_to_timeval(time
);
116 ev
.code
= SYN_DROPPED
;
119 spin_lock_irqsave(&client
->buffer_lock
, flags
);
121 client
->buffer
[client
->head
++] = ev
;
122 client
->head
&= client
->bufsize
- 1;
124 if (unlikely(client
->head
== client
->tail
)) {
125 /* drop queue but keep our SYN_DROPPED event */
126 client
->tail
= (client
->head
- 1) & (client
->bufsize
- 1);
127 client
->packet_head
= client
->tail
;
130 spin_unlock_irqrestore(&client
->buffer_lock
, flags
);
133 static void __pass_event(struct evdev_client
*client
,
134 const struct input_event
*event
)
136 client
->buffer
[client
->head
++] = *event
;
137 client
->head
&= client
->bufsize
- 1;
139 if (unlikely(client
->head
== client
->tail
)) {
141 * This effectively "drops" all unconsumed events, leaving
142 * EV_SYN/SYN_DROPPED plus the newest event in the queue.
144 client
->tail
= (client
->head
- 2) & (client
->bufsize
- 1);
146 client
->buffer
[client
->tail
].time
= event
->time
;
147 client
->buffer
[client
->tail
].type
= EV_SYN
;
148 client
->buffer
[client
->tail
].code
= SYN_DROPPED
;
149 client
->buffer
[client
->tail
].value
= 0;
151 client
->packet_head
= client
->tail
;
154 if (event
->type
== EV_SYN
&& event
->code
== SYN_REPORT
) {
155 client
->packet_head
= client
->head
;
156 kill_fasync(&client
->fasync
, SIGIO
, POLL_IN
);
160 static void evdev_pass_values(struct evdev_client
*client
,
161 const struct input_value
*vals
, unsigned int count
,
162 ktime_t mono
, ktime_t real
)
164 struct evdev
*evdev
= client
->evdev
;
165 const struct input_value
*v
;
166 struct input_event event
;
172 event
.time
= ktime_to_timeval(client
->clkid
== CLOCK_MONOTONIC
?
175 /* Interrupts are disabled, just acquire the lock. */
176 spin_lock(&client
->buffer_lock
);
178 for (v
= vals
; v
!= vals
+ count
; v
++) {
179 event
.type
= v
->type
;
180 event
.code
= v
->code
;
181 event
.value
= v
->value
;
182 __pass_event(client
, &event
);
183 if (v
->type
== EV_SYN
&& v
->code
== SYN_REPORT
)
187 spin_unlock(&client
->buffer_lock
);
190 wake_up_interruptible(&evdev
->wait
);
194 * Pass incoming events to all connected clients.
196 static void evdev_events(struct input_handle
*handle
,
197 const struct input_value
*vals
, unsigned int count
)
199 struct evdev
*evdev
= handle
->private;
200 struct evdev_client
*client
;
201 ktime_t time_mono
, time_real
;
203 time_mono
= ktime_get();
204 time_real
= ktime_mono_to_real(time_mono
);
208 client
= rcu_dereference(evdev
->grab
);
211 evdev_pass_values(client
, vals
, count
, time_mono
, time_real
);
213 list_for_each_entry_rcu(client
, &evdev
->client_list
, node
)
214 evdev_pass_values(client
, vals
, count
,
215 time_mono
, time_real
);
221 * Pass incoming event to all connected clients.
223 static void evdev_event(struct input_handle
*handle
,
224 unsigned int type
, unsigned int code
, int value
)
226 struct input_value vals
[] = { { type
, code
, value
} };
228 evdev_events(handle
, vals
, 1);
231 static int evdev_fasync(int fd
, struct file
*file
, int on
)
233 struct evdev_client
*client
= file
->private_data
;
235 return fasync_helper(fd
, file
, on
, &client
->fasync
);
238 static int evdev_flush(struct file
*file
, fl_owner_t id
)
240 struct evdev_client
*client
= file
->private_data
;
241 struct evdev
*evdev
= client
->evdev
;
244 retval
= mutex_lock_interruptible(&evdev
->mutex
);
248 if (!evdev
->exist
|| client
->revoked
)
251 retval
= input_flush_device(&evdev
->handle
, file
);
253 mutex_unlock(&evdev
->mutex
);
257 static void evdev_free(struct device
*dev
)
259 struct evdev
*evdev
= container_of(dev
, struct evdev
, dev
);
261 input_put_device(evdev
->handle
.dev
);
266 * Grabs an event device (along with underlying input device).
267 * This function is called with evdev->mutex taken.
269 static int evdev_grab(struct evdev
*evdev
, struct evdev_client
*client
)
276 error
= input_grab_device(&evdev
->handle
);
280 rcu_assign_pointer(evdev
->grab
, client
);
285 static int evdev_ungrab(struct evdev
*evdev
, struct evdev_client
*client
)
287 struct evdev_client
*grab
= rcu_dereference_protected(evdev
->grab
,
288 lockdep_is_held(&evdev
->mutex
));
293 rcu_assign_pointer(evdev
->grab
, NULL
);
295 input_release_device(&evdev
->handle
);
300 static void evdev_attach_client(struct evdev
*evdev
,
301 struct evdev_client
*client
)
303 spin_lock(&evdev
->client_lock
);
304 list_add_tail_rcu(&client
->node
, &evdev
->client_list
);
305 spin_unlock(&evdev
->client_lock
);
308 static void evdev_detach_client(struct evdev
*evdev
,
309 struct evdev_client
*client
)
311 spin_lock(&evdev
->client_lock
);
312 list_del_rcu(&client
->node
);
313 spin_unlock(&evdev
->client_lock
);
317 static int evdev_open_device(struct evdev
*evdev
)
321 retval
= mutex_lock_interruptible(&evdev
->mutex
);
327 else if (!evdev
->open
++) {
328 retval
= input_open_device(&evdev
->handle
);
333 mutex_unlock(&evdev
->mutex
);
337 static void evdev_close_device(struct evdev
*evdev
)
339 mutex_lock(&evdev
->mutex
);
341 if (evdev
->exist
&& !--evdev
->open
)
342 input_close_device(&evdev
->handle
);
344 mutex_unlock(&evdev
->mutex
);
348 * Wake up users waiting for IO so they can disconnect from
351 static void evdev_hangup(struct evdev
*evdev
)
353 struct evdev_client
*client
;
355 spin_lock(&evdev
->client_lock
);
356 list_for_each_entry(client
, &evdev
->client_list
, node
)
357 kill_fasync(&client
->fasync
, SIGIO
, POLL_HUP
);
358 spin_unlock(&evdev
->client_lock
);
360 wake_up_interruptible(&evdev
->wait
);
363 static int evdev_release(struct inode
*inode
, struct file
*file
)
365 struct evdev_client
*client
= file
->private_data
;
366 struct evdev
*evdev
= client
->evdev
;
368 mutex_lock(&evdev
->mutex
);
369 evdev_ungrab(evdev
, client
);
370 mutex_unlock(&evdev
->mutex
);
372 evdev_detach_client(evdev
, client
);
374 if (is_vmalloc_addr(client
))
379 evdev_close_device(evdev
);
384 static unsigned int evdev_compute_buffer_size(struct input_dev
*dev
)
386 unsigned int n_events
=
387 max(dev
->hint_events_per_packet
* EVDEV_BUF_PACKETS
,
388 EVDEV_MIN_BUFFER_SIZE
);
390 return roundup_pow_of_two(n_events
);
393 static int evdev_open(struct inode
*inode
, struct file
*file
)
395 struct evdev
*evdev
= container_of(inode
->i_cdev
, struct evdev
, cdev
);
396 unsigned int bufsize
= evdev_compute_buffer_size(evdev
->handle
.dev
);
397 unsigned int size
= sizeof(struct evdev_client
) +
398 bufsize
* sizeof(struct input_event
);
399 struct evdev_client
*client
;
402 client
= kzalloc(size
, GFP_KERNEL
| __GFP_NOWARN
);
404 client
= vzalloc(size
);
408 client
->bufsize
= bufsize
;
409 spin_lock_init(&client
->buffer_lock
);
410 client
->evdev
= evdev
;
411 evdev_attach_client(evdev
, client
);
413 error
= evdev_open_device(evdev
);
415 goto err_free_client
;
417 file
->private_data
= client
;
418 nonseekable_open(inode
, file
);
423 evdev_detach_client(evdev
, client
);
428 static ssize_t
evdev_write(struct file
*file
, const char __user
*buffer
,
429 size_t count
, loff_t
*ppos
)
431 struct evdev_client
*client
= file
->private_data
;
432 struct evdev
*evdev
= client
->evdev
;
433 struct input_event event
;
436 if (count
!= 0 && count
< input_event_size())
439 retval
= mutex_lock_interruptible(&evdev
->mutex
);
443 if (!evdev
->exist
|| client
->revoked
) {
448 while (retval
+ input_event_size() <= count
) {
450 if (input_event_from_user(buffer
+ retval
, &event
)) {
454 retval
+= input_event_size();
456 input_inject_event(&evdev
->handle
,
457 event
.type
, event
.code
, event
.value
);
461 mutex_unlock(&evdev
->mutex
);
465 static int evdev_fetch_next_event(struct evdev_client
*client
,
466 struct input_event
*event
)
470 spin_lock_irq(&client
->buffer_lock
);
472 have_event
= client
->packet_head
!= client
->tail
;
474 *event
= client
->buffer
[client
->tail
++];
475 client
->tail
&= client
->bufsize
- 1;
478 spin_unlock_irq(&client
->buffer_lock
);
483 static ssize_t
evdev_read(struct file
*file
, char __user
*buffer
,
484 size_t count
, loff_t
*ppos
)
486 struct evdev_client
*client
= file
->private_data
;
487 struct evdev
*evdev
= client
->evdev
;
488 struct input_event event
;
492 if (count
!= 0 && count
< input_event_size())
496 if (!evdev
->exist
|| client
->revoked
)
499 if (client
->packet_head
== client
->tail
&&
500 (file
->f_flags
& O_NONBLOCK
))
504 * count == 0 is special - no IO is done but we check
505 * for error conditions (see above).
510 while (read
+ input_event_size() <= count
&&
511 evdev_fetch_next_event(client
, &event
)) {
513 if (input_event_to_user(buffer
+ read
, &event
))
516 read
+= input_event_size();
522 if (!(file
->f_flags
& O_NONBLOCK
)) {
523 error
= wait_event_interruptible(evdev
->wait
,
524 client
->packet_head
!= client
->tail
||
525 !evdev
->exist
|| client
->revoked
);
534 /* No kernel lock - fine */
535 static unsigned int evdev_poll(struct file
*file
, poll_table
*wait
)
537 struct evdev_client
*client
= file
->private_data
;
538 struct evdev
*evdev
= client
->evdev
;
541 poll_wait(file
, &evdev
->wait
, wait
);
543 if (evdev
->exist
&& !client
->revoked
)
544 mask
= POLLOUT
| POLLWRNORM
;
546 mask
= POLLHUP
| POLLERR
;
548 if (client
->packet_head
!= client
->tail
)
549 mask
|= POLLIN
| POLLRDNORM
;
556 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
557 #define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
560 static int bits_to_user(unsigned long *bits
, unsigned int maxbit
,
561 unsigned int maxlen
, void __user
*p
, int compat
)
566 len
= BITS_TO_LONGS_COMPAT(maxbit
) * sizeof(compat_long_t
);
570 for (i
= 0; i
< len
/ sizeof(compat_long_t
); i
++)
571 if (copy_to_user((compat_long_t __user
*) p
+ i
,
572 (compat_long_t
*) bits
+
573 i
+ 1 - ((i
% 2) << 1),
574 sizeof(compat_long_t
)))
577 len
= BITS_TO_LONGS(maxbit
) * sizeof(long);
581 if (copy_to_user(p
, bits
, len
))
588 static int bits_to_user(unsigned long *bits
, unsigned int maxbit
,
589 unsigned int maxlen
, void __user
*p
, int compat
)
592 BITS_TO_LONGS_COMPAT(maxbit
) * sizeof(compat_long_t
) :
593 BITS_TO_LONGS(maxbit
) * sizeof(long);
598 return copy_to_user(p
, bits
, len
) ? -EFAULT
: len
;
600 #endif /* __BIG_ENDIAN */
604 static int bits_to_user(unsigned long *bits
, unsigned int maxbit
,
605 unsigned int maxlen
, void __user
*p
, int compat
)
607 int len
= BITS_TO_LONGS(maxbit
) * sizeof(long);
612 return copy_to_user(p
, bits
, len
) ? -EFAULT
: len
;
615 #endif /* CONFIG_COMPAT */
617 static int str_to_user(const char *str
, unsigned int maxlen
, void __user
*p
)
624 len
= strlen(str
) + 1;
628 return copy_to_user(p
, str
, len
) ? -EFAULT
: len
;
631 static int handle_eviocgbit(struct input_dev
*dev
,
632 unsigned int type
, unsigned int size
,
633 void __user
*p
, int compat_mode
)
640 case 0: bits
= dev
->evbit
; len
= EV_MAX
; break;
641 case EV_KEY
: bits
= dev
->keybit
; len
= KEY_MAX
; break;
642 case EV_REL
: bits
= dev
->relbit
; len
= REL_MAX
; break;
643 case EV_ABS
: bits
= dev
->absbit
; len
= ABS_MAX
; break;
644 case EV_MSC
: bits
= dev
->mscbit
; len
= MSC_MAX
; break;
645 case EV_LED
: bits
= dev
->ledbit
; len
= LED_MAX
; break;
646 case EV_SND
: bits
= dev
->sndbit
; len
= SND_MAX
; break;
647 case EV_FF
: bits
= dev
->ffbit
; len
= FF_MAX
; break;
648 case EV_SW
: bits
= dev
->swbit
; len
= SW_MAX
; break;
649 default: return -EINVAL
;
652 return bits_to_user(bits
, len
, size
, p
, compat_mode
);
655 static int evdev_handle_get_keycode(struct input_dev
*dev
, void __user
*p
)
657 struct input_keymap_entry ke
= {
658 .len
= sizeof(unsigned int),
661 int __user
*ip
= (int __user
*)p
;
665 if (copy_from_user(ke
.scancode
, p
, sizeof(unsigned int)))
668 error
= input_get_keycode(dev
, &ke
);
672 if (put_user(ke
.keycode
, ip
+ 1))
678 static int evdev_handle_get_keycode_v2(struct input_dev
*dev
, void __user
*p
)
680 struct input_keymap_entry ke
;
683 if (copy_from_user(&ke
, p
, sizeof(ke
)))
686 error
= input_get_keycode(dev
, &ke
);
690 if (copy_to_user(p
, &ke
, sizeof(ke
)))
696 static int evdev_handle_set_keycode(struct input_dev
*dev
, void __user
*p
)
698 struct input_keymap_entry ke
= {
699 .len
= sizeof(unsigned int),
702 int __user
*ip
= (int __user
*)p
;
704 if (copy_from_user(ke
.scancode
, p
, sizeof(unsigned int)))
707 if (get_user(ke
.keycode
, ip
+ 1))
710 return input_set_keycode(dev
, &ke
);
713 static int evdev_handle_set_keycode_v2(struct input_dev
*dev
, void __user
*p
)
715 struct input_keymap_entry ke
;
717 if (copy_from_user(&ke
, p
, sizeof(ke
)))
720 if (ke
.len
> sizeof(ke
.scancode
))
723 return input_set_keycode(dev
, &ke
);
727 * If we transfer state to the user, we should flush all pending events
728 * of the same type from the client's queue. Otherwise, they might end up
729 * with duplicate events, which can screw up client's state tracking.
730 * If bits_to_user fails after flushing the queue, we queue a SYN_DROPPED
731 * event so user-space will notice missing events.
734 * We need to take event_lock before buffer_lock to avoid dead-locks. But we
735 * need the even_lock only to guarantee consistent state. We can safely release
736 * it while flushing the queue. This allows input-core to handle filters while
737 * we flush the queue.
739 static int evdev_handle_get_val(struct evdev_client
*client
,
740 struct input_dev
*dev
, unsigned int type
,
741 unsigned long *bits
, unsigned int maxbit
,
742 unsigned int maxlen
, void __user
*p
,
749 len
= BITS_TO_LONGS(maxbit
) * sizeof(unsigned long);
750 mem
= kmalloc(len
, GFP_KERNEL
);
754 spin_lock_irq(&dev
->event_lock
);
755 spin_lock(&client
->buffer_lock
);
757 memcpy(mem
, bits
, len
);
759 spin_unlock(&dev
->event_lock
);
761 __evdev_flush_queue(client
, type
);
763 spin_unlock_irq(&client
->buffer_lock
);
765 ret
= bits_to_user(mem
, maxbit
, maxlen
, p
, compat
);
767 evdev_queue_syn_dropped(client
);
774 static int evdev_handle_mt_request(struct input_dev
*dev
,
778 const struct input_mt
*mt
= dev
->mt
;
783 if (get_user(code
, &ip
[0]))
785 if (!mt
|| !input_is_mt_value(code
))
788 max_slots
= (size
- sizeof(__u32
)) / sizeof(__s32
);
789 for (i
= 0; i
< mt
->num_slots
&& i
< max_slots
; i
++) {
790 int value
= input_mt_get_value(&mt
->slots
[i
], code
);
791 if (put_user(value
, &ip
[1 + i
]))
798 static int evdev_revoke(struct evdev
*evdev
, struct evdev_client
*client
,
801 client
->revoked
= true;
802 evdev_ungrab(evdev
, client
);
803 input_flush_device(&evdev
->handle
, file
);
804 wake_up_interruptible(&evdev
->wait
);
809 static long evdev_do_ioctl(struct file
*file
, unsigned int cmd
,
810 void __user
*p
, int compat_mode
)
812 struct evdev_client
*client
= file
->private_data
;
813 struct evdev
*evdev
= client
->evdev
;
814 struct input_dev
*dev
= evdev
->handle
.dev
;
815 struct input_absinfo abs
;
816 struct ff_effect effect
;
817 int __user
*ip
= (int __user
*)p
;
818 unsigned int i
, t
, u
, v
;
822 /* First we check for fixed-length commands */
826 return put_user(EV_VERSION
, ip
);
829 if (copy_to_user(p
, &dev
->id
, sizeof(struct input_id
)))
834 if (!test_bit(EV_REP
, dev
->evbit
))
836 if (put_user(dev
->rep
[REP_DELAY
], ip
))
838 if (put_user(dev
->rep
[REP_PERIOD
], ip
+ 1))
843 if (!test_bit(EV_REP
, dev
->evbit
))
847 if (get_user(v
, ip
+ 1))
850 input_inject_event(&evdev
->handle
, EV_REP
, REP_DELAY
, u
);
851 input_inject_event(&evdev
->handle
, EV_REP
, REP_PERIOD
, v
);
856 return input_ff_erase(dev
, (int)(unsigned long) p
, file
);
859 i
= test_bit(EV_FF
, dev
->evbit
) ?
860 dev
->ff
->max_effects
: 0;
867 return evdev_grab(evdev
, client
);
869 return evdev_ungrab(evdev
, client
);
875 return evdev_revoke(evdev
, client
, file
);
878 if (copy_from_user(&i
, p
, sizeof(unsigned int)))
880 if (i
!= CLOCK_MONOTONIC
&& i
!= CLOCK_REALTIME
)
886 return evdev_handle_get_keycode(dev
, p
);
889 return evdev_handle_set_keycode(dev
, p
);
891 case EVIOCGKEYCODE_V2
:
892 return evdev_handle_get_keycode_v2(dev
, p
);
894 case EVIOCSKEYCODE_V2
:
895 return evdev_handle_set_keycode_v2(dev
, p
);
898 size
= _IOC_SIZE(cmd
);
900 /* Now check variable-length commands */
901 #define EVIOC_MASK_SIZE(nr) ((nr) & ~(_IOC_SIZEMASK << _IOC_SIZESHIFT))
902 switch (EVIOC_MASK_SIZE(cmd
)) {
905 return bits_to_user(dev
->propbit
, INPUT_PROP_MAX
,
906 size
, p
, compat_mode
);
908 case EVIOCGMTSLOTS(0):
909 return evdev_handle_mt_request(dev
, size
, ip
);
912 return evdev_handle_get_val(client
, dev
, EV_KEY
, dev
->key
,
913 KEY_MAX
, size
, p
, compat_mode
);
916 return evdev_handle_get_val(client
, dev
, EV_LED
, dev
->led
,
917 LED_MAX
, size
, p
, compat_mode
);
920 return evdev_handle_get_val(client
, dev
, EV_SND
, dev
->snd
,
921 SND_MAX
, size
, p
, compat_mode
);
924 return evdev_handle_get_val(client
, dev
, EV_SW
, dev
->sw
,
925 SW_MAX
, size
, p
, compat_mode
);
928 return str_to_user(dev
->name
, size
, p
);
931 return str_to_user(dev
->phys
, size
, p
);
934 return str_to_user(dev
->uniq
, size
, p
);
936 case EVIOC_MASK_SIZE(EVIOCSFF
):
937 if (input_ff_effect_from_user(p
, size
, &effect
))
940 error
= input_ff_upload(dev
, &effect
, file
);
944 if (put_user(effect
.id
, &(((struct ff_effect __user
*)p
)->id
)))
950 /* Multi-number variable-length handlers */
951 if (_IOC_TYPE(cmd
) != 'E')
954 if (_IOC_DIR(cmd
) == _IOC_READ
) {
956 if ((_IOC_NR(cmd
) & ~EV_MAX
) == _IOC_NR(EVIOCGBIT(0, 0)))
957 return handle_eviocgbit(dev
,
958 _IOC_NR(cmd
) & EV_MAX
, size
,
961 if ((_IOC_NR(cmd
) & ~ABS_MAX
) == _IOC_NR(EVIOCGABS(0))) {
966 t
= _IOC_NR(cmd
) & ABS_MAX
;
967 abs
= dev
->absinfo
[t
];
969 if (copy_to_user(p
, &abs
, min_t(size_t,
970 size
, sizeof(struct input_absinfo
))))
977 if (_IOC_DIR(cmd
) == _IOC_WRITE
) {
979 if ((_IOC_NR(cmd
) & ~ABS_MAX
) == _IOC_NR(EVIOCSABS(0))) {
984 t
= _IOC_NR(cmd
) & ABS_MAX
;
986 if (copy_from_user(&abs
, p
, min_t(size_t,
987 size
, sizeof(struct input_absinfo
))))
990 if (size
< sizeof(struct input_absinfo
))
993 /* We can't change number of reserved MT slots */
994 if (t
== ABS_MT_SLOT
)
998 * Take event lock to ensure that we are not
999 * changing device parameters in the middle
1002 spin_lock_irq(&dev
->event_lock
);
1003 dev
->absinfo
[t
] = abs
;
1004 spin_unlock_irq(&dev
->event_lock
);
1013 static long evdev_ioctl_handler(struct file
*file
, unsigned int cmd
,
1014 void __user
*p
, int compat_mode
)
1016 struct evdev_client
*client
= file
->private_data
;
1017 struct evdev
*evdev
= client
->evdev
;
1020 retval
= mutex_lock_interruptible(&evdev
->mutex
);
1024 if (!evdev
->exist
|| client
->revoked
) {
1029 retval
= evdev_do_ioctl(file
, cmd
, p
, compat_mode
);
1032 mutex_unlock(&evdev
->mutex
);
1036 static long evdev_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
1038 return evdev_ioctl_handler(file
, cmd
, (void __user
*)arg
, 0);
1041 #ifdef CONFIG_COMPAT
1042 static long evdev_ioctl_compat(struct file
*file
,
1043 unsigned int cmd
, unsigned long arg
)
1045 return evdev_ioctl_handler(file
, cmd
, compat_ptr(arg
), 1);
1049 static const struct file_operations evdev_fops
= {
1050 .owner
= THIS_MODULE
,
1052 .write
= evdev_write
,
1055 .release
= evdev_release
,
1056 .unlocked_ioctl
= evdev_ioctl
,
1057 #ifdef CONFIG_COMPAT
1058 .compat_ioctl
= evdev_ioctl_compat
,
1060 .fasync
= evdev_fasync
,
1061 .flush
= evdev_flush
,
1062 .llseek
= no_llseek
,
1066 * Mark device non-existent. This disables writes, ioctls and
1067 * prevents new users from opening the device. Already posted
1068 * blocking reads will stay, however new ones will fail.
1070 static void evdev_mark_dead(struct evdev
*evdev
)
1072 mutex_lock(&evdev
->mutex
);
1073 evdev
->exist
= false;
1074 mutex_unlock(&evdev
->mutex
);
1077 static void evdev_cleanup(struct evdev
*evdev
)
1079 struct input_handle
*handle
= &evdev
->handle
;
1081 evdev_mark_dead(evdev
);
1082 evdev_hangup(evdev
);
1084 cdev_del(&evdev
->cdev
);
1086 /* evdev is marked dead so no one else accesses evdev->open */
1088 input_flush_device(handle
, NULL
);
1089 input_close_device(handle
);
1094 * Create new evdev device. Note that input core serializes calls
1095 * to connect and disconnect.
1097 static int evdev_connect(struct input_handler
*handler
, struct input_dev
*dev
,
1098 const struct input_device_id
*id
)
1100 struct evdev
*evdev
;
1105 minor
= input_get_new_minor(EVDEV_MINOR_BASE
, EVDEV_MINORS
, true);
1108 pr_err("failed to reserve new minor: %d\n", error
);
1112 evdev
= kzalloc(sizeof(struct evdev
), GFP_KERNEL
);
1115 goto err_free_minor
;
1118 INIT_LIST_HEAD(&evdev
->client_list
);
1119 spin_lock_init(&evdev
->client_lock
);
1120 mutex_init(&evdev
->mutex
);
1121 init_waitqueue_head(&evdev
->wait
);
1122 evdev
->exist
= true;
1125 /* Normalize device number if it falls into legacy range */
1126 if (dev_no
< EVDEV_MINOR_BASE
+ EVDEV_MINORS
)
1127 dev_no
-= EVDEV_MINOR_BASE
;
1128 dev_set_name(&evdev
->dev
, "event%d", dev_no
);
1130 evdev
->handle
.dev
= input_get_device(dev
);
1131 evdev
->handle
.name
= dev_name(&evdev
->dev
);
1132 evdev
->handle
.handler
= handler
;
1133 evdev
->handle
.private = evdev
;
1135 evdev
->dev
.devt
= MKDEV(INPUT_MAJOR
, minor
);
1136 evdev
->dev
.class = &input_class
;
1137 evdev
->dev
.parent
= &dev
->dev
;
1138 evdev
->dev
.release
= evdev_free
;
1139 device_initialize(&evdev
->dev
);
1141 error
= input_register_handle(&evdev
->handle
);
1143 goto err_free_evdev
;
1145 cdev_init(&evdev
->cdev
, &evdev_fops
);
1146 evdev
->cdev
.kobj
.parent
= &evdev
->dev
.kobj
;
1147 error
= cdev_add(&evdev
->cdev
, evdev
->dev
.devt
, 1);
1149 goto err_unregister_handle
;
1151 error
= device_add(&evdev
->dev
);
1153 goto err_cleanup_evdev
;
1158 evdev_cleanup(evdev
);
1159 err_unregister_handle
:
1160 input_unregister_handle(&evdev
->handle
);
1162 put_device(&evdev
->dev
);
1164 input_free_minor(minor
);
1168 static void evdev_disconnect(struct input_handle
*handle
)
1170 struct evdev
*evdev
= handle
->private;
1172 device_del(&evdev
->dev
);
1173 evdev_cleanup(evdev
);
1174 input_free_minor(MINOR(evdev
->dev
.devt
));
1175 input_unregister_handle(handle
);
1176 put_device(&evdev
->dev
);
1179 static const struct input_device_id evdev_ids
[] = {
1180 { .driver_info
= 1 }, /* Matches all devices */
1181 { }, /* Terminating zero entry */
1184 MODULE_DEVICE_TABLE(input
, evdev_ids
);
1186 static struct input_handler evdev_handler
= {
1187 .event
= evdev_event
,
1188 .events
= evdev_events
,
1189 .connect
= evdev_connect
,
1190 .disconnect
= evdev_disconnect
,
1191 .legacy_minors
= true,
1192 .minor
= EVDEV_MINOR_BASE
,
1194 .id_table
= evdev_ids
,
1197 static int __init
evdev_init(void)
1199 return input_register_handler(&evdev_handler
);
1202 static void __exit
evdev_exit(void)
1204 input_unregister_handler(&evdev_handler
);
1207 module_init(evdev_init
);
1208 module_exit(evdev_exit
);
1210 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
1211 MODULE_DESCRIPTION("Input driver event char devices");
1212 MODULE_LICENSE("GPL");