projects/linux·blob v2.6.28 · refs

1075 lines · 24.1 KiB

1/*
2 * Event char devices, giving access to raw input device events.
3 *
4 * Copyright (c) 1999-2002 Vojtech Pavlik
5 *
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.
9 */
10
11#define EVDEV_MINOR_BASE 64
12#define EVDEV_MINORS 32
13#define EVDEV_BUFFER_SIZE 64
14
15#include <linux/poll.h>
16#include <linux/slab.h>
17#include <linux/module.h>
18#include <linux/init.h>
19#include <linux/input.h>
20#include <linux/major.h>
21#include <linux/device.h>
22#include <linux/compat.h>
23
24struct evdev {
25 int exist;
26 int open;
27 int minor;
28 char name[16];
29 struct input_handle handle;
30 wait_queue_head_t wait;
31 struct evdev_client *grab;
32 struct list_head client_list;
33 spinlock_t client_lock; /* protects client_list */
34 struct mutex mutex;
35 struct device dev;
36};
37
38struct evdev_client {
39 struct input_event buffer[EVDEV_BUFFER_SIZE];
40 int head;
41 int tail;
42 spinlock_t buffer_lock; /* protects access to buffer, head and tail */
43 struct fasync_struct *fasync;
44 struct evdev *evdev;
45 struct list_head node;
46};
47
48static struct evdev *evdev_table[EVDEV_MINORS];
49static DEFINE_MUTEX(evdev_table_mutex);
50
51static void evdev_pass_event(struct evdev_client *client,
52 struct input_event *event)
53{
54 /*
55 * Interrupts are disabled, just acquire the lock
56 */
57 spin_lock(&client->buffer_lock);
58 client->buffer[client->head++] = *event;
59 client->head &= EVDEV_BUFFER_SIZE - 1;
60 spin_unlock(&client->buffer_lock);
61
62 kill_fasync(&client->fasync, SIGIO, POLL_IN);
63}
64
65/*
66 * Pass incoming event to all connected clients.
67 */
68static void evdev_event(struct input_handle *handle,
69 unsigned int type, unsigned int code, int value)
70{
71 struct evdev *evdev = handle->private;
72 struct evdev_client *client;
73 struct input_event event;
74
75 do_gettimeofday(&event.time);
76 event.type = type;
77 event.code = code;
78 event.value = value;
79
80 rcu_read_lock();
81
82 client = rcu_dereference(evdev->grab);
83 if (client)
84 evdev_pass_event(client, &event);
85 else
86 list_for_each_entry_rcu(client, &evdev->client_list, node)
87 evdev_pass_event(client, &event);
88
89 rcu_read_unlock();
90
91 wake_up_interruptible(&evdev->wait);
92}
93
94static int evdev_fasync(int fd, struct file *file, int on)
95{
96 struct evdev_client *client = file->private_data;
97 int retval;
98
99 retval = fasync_helper(fd, file, on, &client->fasync);
100
101 return retval < 0 ? retval : 0;
102}
103
104static int evdev_flush(struct file *file, fl_owner_t id)
105{
106 struct evdev_client *client = file->private_data;
107 struct evdev *evdev = client->evdev;
108 int retval;
109
110 retval = mutex_lock_interruptible(&evdev->mutex);
111 if (retval)
112 return retval;
113
114 if (!evdev->exist)
115 retval = -ENODEV;
116 else
117 retval = input_flush_device(&evdev->handle, file);
118
119 mutex_unlock(&evdev->mutex);
120 return retval;
121}
122
123static void evdev_free(struct device *dev)
124{
125 struct evdev *evdev = container_of(dev, struct evdev, dev);
126
127 input_put_device(evdev->handle.dev);
128 kfree(evdev);
129}
130
131/*
132 * Grabs an event device (along with underlying input device).
133 * This function is called with evdev->mutex taken.
134 */
135static int evdev_grab(struct evdev *evdev, struct evdev_client *client)
136{
137 int error;
138
139 if (evdev->grab)
140 return -EBUSY;
141
142 error = input_grab_device(&evdev->handle);
143 if (error)
144 return error;
145
146 rcu_assign_pointer(evdev->grab, client);
147 synchronize_rcu();
148
149 return 0;
150}
151
152static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client)
153{
154 if (evdev->grab != client)
155 return -EINVAL;
156
157 rcu_assign_pointer(evdev->grab, NULL);
158 synchronize_rcu();
159 input_release_device(&evdev->handle);
160
161 return 0;
162}
163
164static void evdev_attach_client(struct evdev *evdev,
165 struct evdev_client *client)
166{
167 spin_lock(&evdev->client_lock);
168 list_add_tail_rcu(&client->node, &evdev->client_list);
169 spin_unlock(&evdev->client_lock);
170 synchronize_rcu();
171}
172
173static void evdev_detach_client(struct evdev *evdev,
174 struct evdev_client *client)
175{
176 spin_lock(&evdev->client_lock);
177 list_del_rcu(&client->node);
178 spin_unlock(&evdev->client_lock);
179 synchronize_rcu();
180}
181
182static int evdev_open_device(struct evdev *evdev)
183{
184 int retval;
185
186 retval = mutex_lock_interruptible(&evdev->mutex);
187 if (retval)
188 return retval;
189
190 if (!evdev->exist)
191 retval = -ENODEV;
192 else if (!evdev->open++) {
193 retval = input_open_device(&evdev->handle);
194 if (retval)
195 evdev->open--;
196 }
197
198 mutex_unlock(&evdev->mutex);
199 return retval;
200}
201
202static void evdev_close_device(struct evdev *evdev)
203{
204 mutex_lock(&evdev->mutex);
205
206 if (evdev->exist && !--evdev->open)
207 input_close_device(&evdev->handle);
208
209 mutex_unlock(&evdev->mutex);
210}
211
212/*
213 * Wake up users waiting for IO so they can disconnect from
214 * dead device.
215 */
216static void evdev_hangup(struct evdev *evdev)
217{
218 struct evdev_client *client;
219
220 spin_lock(&evdev->client_lock);
221 list_for_each_entry(client, &evdev->client_list, node)
222 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
223 spin_unlock(&evdev->client_lock);
224
225 wake_up_interruptible(&evdev->wait);
226}
227
228static int evdev_release(struct inode *inode, struct file *file)
229{
230 struct evdev_client *client = file->private_data;
231 struct evdev *evdev = client->evdev;
232
233 mutex_lock(&evdev->mutex);
234 if (evdev->grab == client)
235 evdev_ungrab(evdev, client);
236 mutex_unlock(&evdev->mutex);
237
238 evdev_detach_client(evdev, client);
239 kfree(client);
240
241 evdev_close_device(evdev);
242 put_device(&evdev->dev);
243
244 return 0;
245}
246
247static int evdev_open(struct inode *inode, struct file *file)
248{
249 struct evdev *evdev;
250 struct evdev_client *client;
251 int i = iminor(inode) - EVDEV_MINOR_BASE;
252 int error;
253
254 if (i >= EVDEV_MINORS)
255 return -ENODEV;
256
257 error = mutex_lock_interruptible(&evdev_table_mutex);
258 if (error)
259 return error;
260 evdev = evdev_table[i];
261 if (evdev)
262 get_device(&evdev->dev);
263 mutex_unlock(&evdev_table_mutex);
264
265 if (!evdev)
266 return -ENODEV;
267
268 client = kzalloc(sizeof(struct evdev_client), GFP_KERNEL);
269 if (!client) {
270 error = -ENOMEM;
271 goto err_put_evdev;
272 }
273
274 spin_lock_init(&client->buffer_lock);
275 client->evdev = evdev;
276 evdev_attach_client(evdev, client);
277
278 error = evdev_open_device(evdev);
279 if (error)
280 goto err_free_client;
281
282 file->private_data = client;
283 return 0;
284
285 err_free_client:
286 evdev_detach_client(evdev, client);
287 kfree(client);
288 err_put_evdev:
289 put_device(&evdev->dev);
290 return error;
291}
292
293#ifdef CONFIG_COMPAT
294
295struct input_event_compat {
296 struct compat_timeval time;
297 __u16 type;
298 __u16 code;
299 __s32 value;
300};
301
302struct ff_periodic_effect_compat {
303 __u16 waveform;
304 __u16 period;
305 __s16 magnitude;
306 __s16 offset;
307 __u16 phase;
308
309 struct ff_envelope envelope;
310
311 __u32 custom_len;
312 compat_uptr_t custom_data;
313};
314
315struct ff_effect_compat {
316 __u16 type;
317 __s16 id;
318 __u16 direction;
319 struct ff_trigger trigger;
320 struct ff_replay replay;
321
322 union {
323 struct ff_constant_effect constant;
324 struct ff_ramp_effect ramp;
325 struct ff_periodic_effect_compat periodic;
326 struct ff_condition_effect condition[2]; /* One for each axis */
327 struct ff_rumble_effect rumble;
328 } u;
329};
330
331/* Note to the author of this code: did it ever occur to
332 you why the ifdefs are needed? Think about it again. -AK */
333#ifdef CONFIG_X86_64
334# define COMPAT_TEST is_compat_task()
335#elif defined(CONFIG_IA64)
336# define COMPAT_TEST IS_IA32_PROCESS(task_pt_regs(current))
337#elif defined(CONFIG_S390)
338# define COMPAT_TEST test_thread_flag(TIF_31BIT)
339#elif defined(CONFIG_MIPS)
340# define COMPAT_TEST test_thread_flag(TIF_32BIT_ADDR)
341#else
342# define COMPAT_TEST test_thread_flag(TIF_32BIT)
343#endif
344
345static inline size_t evdev_event_size(void)
346{
347 return COMPAT_TEST ?
348 sizeof(struct input_event_compat) : sizeof(struct input_event);
349}
350
351static int evdev_event_from_user(const char __user *buffer,
352 struct input_event *event)
353{
354 if (COMPAT_TEST) {
355 struct input_event_compat compat_event;
356
357 if (copy_from_user(&compat_event, buffer,
358 sizeof(struct input_event_compat)))
359 return -EFAULT;
360
361 event->time.tv_sec = compat_event.time.tv_sec;
362 event->time.tv_usec = compat_event.time.tv_usec;
363 event->type = compat_event.type;
364 event->code = compat_event.code;
365 event->value = compat_event.value;
366
367 } else {
368 if (copy_from_user(event, buffer, sizeof(struct input_event)))
369 return -EFAULT;
370 }
371
372 return 0;
373}
374
375static int evdev_event_to_user(char __user *buffer,
376 const struct input_event *event)
377{
378 if (COMPAT_TEST) {
379 struct input_event_compat compat_event;
380
381 compat_event.time.tv_sec = event->time.tv_sec;
382 compat_event.time.tv_usec = event->time.tv_usec;
383 compat_event.type = event->type;
384 compat_event.code = event->code;
385 compat_event.value = event->value;
386
387 if (copy_to_user(buffer, &compat_event,
388 sizeof(struct input_event_compat)))
389 return -EFAULT;
390
391 } else {
392 if (copy_to_user(buffer, event, sizeof(struct input_event)))
393 return -EFAULT;
394 }
395
396 return 0;
397}
398
399static int evdev_ff_effect_from_user(const char __user *buffer, size_t size,
400 struct ff_effect *effect)
401{
402 if (COMPAT_TEST) {
403 struct ff_effect_compat *compat_effect;
404
405 if (size != sizeof(struct ff_effect_compat))
406 return -EINVAL;
407
408 /*
409 * It so happens that the pointer which needs to be changed
410 * is the last field in the structure, so we can copy the
411 * whole thing and replace just the pointer.
412 */
413
414 compat_effect = (struct ff_effect_compat *)effect;
415
416 if (copy_from_user(compat_effect, buffer,
417 sizeof(struct ff_effect_compat)))
418 return -EFAULT;
419
420 if (compat_effect->type == FF_PERIODIC &&
421 compat_effect->u.periodic.waveform == FF_CUSTOM)
422 effect->u.periodic.custom_data =
423 compat_ptr(compat_effect->u.periodic.custom_data);
424 } else {
425 if (size != sizeof(struct ff_effect))
426 return -EINVAL;
427
428 if (copy_from_user(effect, buffer, sizeof(struct ff_effect)))
429 return -EFAULT;
430 }
431
432 return 0;
433}
434
435#else
436
437static inline size_t evdev_event_size(void)
438{
439 return sizeof(struct input_event);
440}
441
442static int evdev_event_from_user(const char __user *buffer,
443 struct input_event *event)
444{
445 if (copy_from_user(event, buffer, sizeof(struct input_event)))
446 return -EFAULT;
447
448 return 0;
449}
450
451static int evdev_event_to_user(char __user *buffer,
452 const struct input_event *event)
453{
454 if (copy_to_user(buffer, event, sizeof(struct input_event)))
455 return -EFAULT;
456
457 return 0;
458}
459
460static int evdev_ff_effect_from_user(const char __user *buffer, size_t size,
461 struct ff_effect *effect)
462{
463 if (size != sizeof(struct ff_effect))
464 return -EINVAL;
465
466 if (copy_from_user(effect, buffer, sizeof(struct ff_effect)))
467 return -EFAULT;
468
469 return 0;
470}
471
472#endif /* CONFIG_COMPAT */
473
474static ssize_t evdev_write(struct file *file, const char __user *buffer,
475 size_t count, loff_t *ppos)
476{
477 struct evdev_client *client = file->private_data;
478 struct evdev *evdev = client->evdev;
479 struct input_event event;
480 int retval;
481
482 retval = mutex_lock_interruptible(&evdev->mutex);
483 if (retval)
484 return retval;
485
486 if (!evdev->exist) {
487 retval = -ENODEV;
488 goto out;
489 }
490
491 while (retval < count) {
492
493 if (evdev_event_from_user(buffer + retval, &event)) {
494 retval = -EFAULT;
495 goto out;
496 }
497
498 input_inject_event(&evdev->handle,
499 event.type, event.code, event.value);
500 retval += evdev_event_size();
501 }
502
503 out:
504 mutex_unlock(&evdev->mutex);
505 return retval;
506}
507
508static int evdev_fetch_next_event(struct evdev_client *client,
509 struct input_event *event)
510{
511 int have_event;
512
513 spin_lock_irq(&client->buffer_lock);
514
515 have_event = client->head != client->tail;
516 if (have_event) {
517 *event = client->buffer[client->tail++];
518 client->tail &= EVDEV_BUFFER_SIZE - 1;
519 }
520
521 spin_unlock_irq(&client->buffer_lock);
522
523 return have_event;
524}
525
526static ssize_t evdev_read(struct file *file, char __user *buffer,
527 size_t count, loff_t *ppos)
528{
529 struct evdev_client *client = file->private_data;
530 struct evdev *evdev = client->evdev;
531 struct input_event event;
532 int retval;
533
534 if (count < evdev_event_size())
535 return -EINVAL;
536
537 if (client->head == client->tail && evdev->exist &&
538 (file->f_flags & O_NONBLOCK))
539 return -EAGAIN;
540
541 retval = wait_event_interruptible(evdev->wait,
542 client->head != client->tail || !evdev->exist);
543 if (retval)
544 return retval;
545
546 if (!evdev->exist)
547 return -ENODEV;
548
549 while (retval + evdev_event_size() <= count &&
550 evdev_fetch_next_event(client, &event)) {
551
552 if (evdev_event_to_user(buffer + retval, &event))
553 return -EFAULT;
554
555 retval += evdev_event_size();
556 }
557
558 return retval;
559}
560
561/* No kernel lock - fine */
562static unsigned int evdev_poll(struct file *file, poll_table *wait)
563{
564 struct evdev_client *client = file->private_data;
565 struct evdev *evdev = client->evdev;
566
567 poll_wait(file, &evdev->wait, wait);
568 return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) |
569 (evdev->exist ? 0 : (POLLHUP | POLLERR));
570}
571
572#ifdef CONFIG_COMPAT
573
574#define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
575#define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
576
577#ifdef __BIG_ENDIAN
578static int bits_to_user(unsigned long *bits, unsigned int maxbit,
579 unsigned int maxlen, void __user *p, int compat)
580{
581 int len, i;
582
583 if (compat) {
584 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t);
585 if (len > maxlen)
586 len = maxlen;
587
588 for (i = 0; i < len / sizeof(compat_long_t); i++)
589 if (copy_to_user((compat_long_t __user *) p + i,
590 (compat_long_t *) bits +
591 i + 1 - ((i % 2) << 1),
592 sizeof(compat_long_t)))
593 return -EFAULT;
594 } else {
595 len = BITS_TO_LONGS(maxbit) * sizeof(long);
596 if (len > maxlen)
597 len = maxlen;
598
599 if (copy_to_user(p, bits, len))
600 return -EFAULT;
601 }
602
603 return len;
604}
605#else
606static int bits_to_user(unsigned long *bits, unsigned int maxbit,
607 unsigned int maxlen, void __user *p, int compat)
608{
609 int len = compat ?
610 BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) :
611 BITS_TO_LONGS(maxbit) * sizeof(long);
612
613 if (len > maxlen)
614 len = maxlen;
615
616 return copy_to_user(p, bits, len) ? -EFAULT : len;
617}
618#endif /* __BIG_ENDIAN */
619
620#else
621
622static int bits_to_user(unsigned long *bits, unsigned int maxbit,
623 unsigned int maxlen, void __user *p, int compat)
624{
625 int len = BITS_TO_LONGS(maxbit) * sizeof(long);
626
627 if (len > maxlen)
628 len = maxlen;
629
630 return copy_to_user(p, bits, len) ? -EFAULT : len;
631}
632
633#endif /* CONFIG_COMPAT */
634
635static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
636{
637 int len;
638
639 if (!str)
640 return -ENOENT;
641
642 len = strlen(str) + 1;
643 if (len > maxlen)
644 len = maxlen;
645
646 return copy_to_user(p, str, len) ? -EFAULT : len;
647}
648
649#define OLD_KEY_MAX 0x1ff
650static int handle_eviocgbit(struct input_dev *dev, unsigned int cmd, void __user *p, int compat_mode)
651{
652 static unsigned long keymax_warn_time;
653 unsigned long *bits;
654 int len;
655
656 switch (_IOC_NR(cmd) & EV_MAX) {
657
658 case 0: bits = dev->evbit; len = EV_MAX; break;
659 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
660 case EV_REL: bits = dev->relbit; len = REL_MAX; break;
661 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
662 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
663 case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
664 case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
665 case EV_FF: bits = dev->ffbit; len = FF_MAX; break;
666 case EV_SW: bits = dev->swbit; len = SW_MAX; break;
667 default: return -EINVAL;
668 }
669
670 /*
671 * Work around bugs in userspace programs that like to do
672 * EVIOCGBIT(EV_KEY, KEY_MAX) and not realize that 'len'
673 * should be in bytes, not in bits.
674 */
675 if ((_IOC_NR(cmd) & EV_MAX) == EV_KEY && _IOC_SIZE(cmd) == OLD_KEY_MAX) {
676 len = OLD_KEY_MAX;
677 if (printk_timed_ratelimit(&keymax_warn_time, 10 * 1000))
678 printk(KERN_WARNING
679 "evdev.c(EVIOCGBIT): Suspicious buffer size %u, "
680 "limiting output to %zu bytes. See "
681 "http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n",
682 OLD_KEY_MAX,
683 BITS_TO_LONGS(OLD_KEY_MAX) * sizeof(long));
684 }
685
686 return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode);
687}
688#undef OLD_KEY_MAX
689
690static long evdev_do_ioctl(struct file *file, unsigned int cmd,
691 void __user *p, int compat_mode)
692{
693 struct evdev_client *client = file->private_data;
694 struct evdev *evdev = client->evdev;
695 struct input_dev *dev = evdev->handle.dev;
696 struct input_absinfo abs;
697 struct ff_effect effect;
698 int __user *ip = (int __user *)p;
699 int i, t, u, v;
700 int error;
701
702 switch (cmd) {
703
704 case EVIOCGVERSION:
705 return put_user(EV_VERSION, ip);
706
707 case EVIOCGID:
708 if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
709 return -EFAULT;
710 return 0;
711
712 case EVIOCGREP:
713 if (!test_bit(EV_REP, dev->evbit))
714 return -ENOSYS;
715 if (put_user(dev->rep[REP_DELAY], ip))
716 return -EFAULT;
717 if (put_user(dev->rep[REP_PERIOD], ip + 1))
718 return -EFAULT;
719 return 0;
720
721 case EVIOCSREP:
722 if (!test_bit(EV_REP, dev->evbit))
723 return -ENOSYS;
724 if (get_user(u, ip))
725 return -EFAULT;
726 if (get_user(v, ip + 1))
727 return -EFAULT;
728
729 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
730 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
731
732 return 0;
733
734 case EVIOCGKEYCODE:
735 if (get_user(t, ip))
736 return -EFAULT;
737
738 error = input_get_keycode(dev, t, &v);
739 if (error)
740 return error;
741
742 if (put_user(v, ip + 1))
743 return -EFAULT;
744
745 return 0;
746
747 case EVIOCSKEYCODE:
748 if (get_user(t, ip) || get_user(v, ip + 1))
749 return -EFAULT;
750
751 return input_set_keycode(dev, t, v);
752
753 case EVIOCRMFF:
754 return input_ff_erase(dev, (int)(unsigned long) p, file);
755
756 case EVIOCGEFFECTS:
757 i = test_bit(EV_FF, dev->evbit) ?
758 dev->ff->max_effects : 0;
759 if (put_user(i, ip))
760 return -EFAULT;
761 return 0;
762
763 case EVIOCGRAB:
764 if (p)
765 return evdev_grab(evdev, client);
766 else
767 return evdev_ungrab(evdev, client);
768
769 default:
770
771 if (_IOC_TYPE(cmd) != 'E')
772 return -EINVAL;
773
774 if (_IOC_DIR(cmd) == _IOC_READ) {
775
776 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0)))
777 return handle_eviocgbit(dev, cmd, p, compat_mode);
778
779 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
780 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd),
781 p, compat_mode);
782
783 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
784 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd),
785 p, compat_mode);
786
787 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
788 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd),
789 p, compat_mode);
790
791 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0)))
792 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd),
793 p, compat_mode);
794
795 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0)))
796 return str_to_user(dev->name, _IOC_SIZE(cmd), p);
797
798 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0)))
799 return str_to_user(dev->phys, _IOC_SIZE(cmd), p);
800
801 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0)))
802 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p);
803
804 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
805
806 t = _IOC_NR(cmd) & ABS_MAX;
807
808 abs.value = dev->abs[t];
809 abs.minimum = dev->absmin[t];
810 abs.maximum = dev->absmax[t];
811 abs.fuzz = dev->absfuzz[t];
812 abs.flat = dev->absflat[t];
813
814 if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
815 return -EFAULT;
816
817 return 0;
818 }
819
820 }
821
822 if (_IOC_DIR(cmd) == _IOC_WRITE) {
823
824 if (_IOC_NR(cmd) == _IOC_NR(EVIOCSFF)) {
825
826 if (evdev_ff_effect_from_user(p, _IOC_SIZE(cmd), &effect))
827 return -EFAULT;
828
829 error = input_ff_upload(dev, &effect, file);
830
831 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
832 return -EFAULT;
833
834 return error;
835 }
836
837 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
838
839 t = _IOC_NR(cmd) & ABS_MAX;
840
841 if (copy_from_user(&abs, p,
842 sizeof(struct input_absinfo)))
843 return -EFAULT;
844
845 /*
846 * Take event lock to ensure that we are not
847 * changing device parameters in the middle
848 * of event.
849 */
850 spin_lock_irq(&dev->event_lock);
851
852 dev->abs[t] = abs.value;
853 dev->absmin[t] = abs.minimum;
854 dev->absmax[t] = abs.maximum;
855 dev->absfuzz[t] = abs.fuzz;
856 dev->absflat[t] = abs.flat;
857
858 spin_unlock_irq(&dev->event_lock);
859
860 return 0;
861 }
862 }
863 }
864 return -EINVAL;
865}
866
867static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
868 void __user *p, int compat_mode)
869{
870 struct evdev_client *client = file->private_data;
871 struct evdev *evdev = client->evdev;
872 int retval;
873
874 retval = mutex_lock_interruptible(&evdev->mutex);
875 if (retval)
876 return retval;
877
878 if (!evdev->exist) {
879 retval = -ENODEV;
880 goto out;
881 }
882
883 retval = evdev_do_ioctl(file, cmd, p, compat_mode);
884
885 out:
886 mutex_unlock(&evdev->mutex);
887 return retval;
888}
889
890static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
891{
892 return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
893}
894
895#ifdef CONFIG_COMPAT
896static long evdev_ioctl_compat(struct file *file,
897 unsigned int cmd, unsigned long arg)
898{
899 return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
900}
901#endif
902
903static const struct file_operations evdev_fops = {
904 .owner = THIS_MODULE,
905 .read = evdev_read,
906 .write = evdev_write,
907 .poll = evdev_poll,
908 .open = evdev_open,
909 .release = evdev_release,
910 .unlocked_ioctl = evdev_ioctl,
911#ifdef CONFIG_COMPAT
912 .compat_ioctl = evdev_ioctl_compat,
913#endif
914 .fasync = evdev_fasync,
915 .flush = evdev_flush
916};
917
918static int evdev_install_chrdev(struct evdev *evdev)
919{
920 /*
921 * No need to do any locking here as calls to connect and
922 * disconnect are serialized by the input core
923 */
924 evdev_table[evdev->minor] = evdev;
925 return 0;
926}
927
928static void evdev_remove_chrdev(struct evdev *evdev)
929{
930 /*
931 * Lock evdev table to prevent race with evdev_open()
932 */
933 mutex_lock(&evdev_table_mutex);
934 evdev_table[evdev->minor] = NULL;
935 mutex_unlock(&evdev_table_mutex);
936}
937
938/*
939 * Mark device non-existent. This disables writes, ioctls and
940 * prevents new users from opening the device. Already posted
941 * blocking reads will stay, however new ones will fail.
942 */
943static void evdev_mark_dead(struct evdev *evdev)
944{
945 mutex_lock(&evdev->mutex);
946 evdev->exist = 0;
947 mutex_unlock(&evdev->mutex);
948}
949
950static void evdev_cleanup(struct evdev *evdev)
951{
952 struct input_handle *handle = &evdev->handle;
953
954 evdev_mark_dead(evdev);
955 evdev_hangup(evdev);
956 evdev_remove_chrdev(evdev);
957
958 /* evdev is marked dead so no one else accesses evdev->open */
959 if (evdev->open) {
960 input_flush_device(handle, NULL);
961 input_close_device(handle);
962 }
963}
964
965/*
966 * Create new evdev device. Note that input core serializes calls
967 * to connect and disconnect so we don't need to lock evdev_table here.
968 */
969static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
970 const struct input_device_id *id)
971{
972 struct evdev *evdev;
973 int minor;
974 int error;
975
976 for (minor = 0; minor < EVDEV_MINORS; minor++)
977 if (!evdev_table[minor])
978 break;
979
980 if (minor == EVDEV_MINORS) {
981 printk(KERN_ERR "evdev: no more free evdev devices\n");
982 return -ENFILE;
983 }
984
985 evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
986 if (!evdev)
987 return -ENOMEM;
988
989 INIT_LIST_HEAD(&evdev->client_list);
990 spin_lock_init(&evdev->client_lock);
991 mutex_init(&evdev->mutex);
992 init_waitqueue_head(&evdev->wait);
993
994 snprintf(evdev->name, sizeof(evdev->name), "event%d", minor);
995 evdev->exist = 1;
996 evdev->minor = minor;
997
998 evdev->handle.dev = input_get_device(dev);
999 evdev->handle.name = evdev->name;
1000 evdev->handle.handler = handler;
1001 evdev->handle.private = evdev;
1002
1003 strlcpy(evdev->dev.bus_id, evdev->name, sizeof(evdev->dev.bus_id));
1004 evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor);
1005 evdev->dev.class = &input_class;
1006 evdev->dev.parent = &dev->dev;
1007 evdev->dev.release = evdev_free;
1008 device_initialize(&evdev->dev);
1009
1010 error = input_register_handle(&evdev->handle);
1011 if (error)
1012 goto err_free_evdev;
1013
1014 error = evdev_install_chrdev(evdev);
1015 if (error)
1016 goto err_unregister_handle;
1017
1018 error = device_add(&evdev->dev);
1019 if (error)
1020 goto err_cleanup_evdev;
1021
1022 return 0;
1023
1024 err_cleanup_evdev:
1025 evdev_cleanup(evdev);
1026 err_unregister_handle:
1027 input_unregister_handle(&evdev->handle);
1028 err_free_evdev:
1029 put_device(&evdev->dev);
1030 return error;
1031}
1032
1033static void evdev_disconnect(struct input_handle *handle)
1034{
1035 struct evdev *evdev = handle->private;
1036
1037 device_del(&evdev->dev);
1038 evdev_cleanup(evdev);
1039 input_unregister_handle(handle);
1040 put_device(&evdev->dev);
1041}
1042
1043static const struct input_device_id evdev_ids[] = {
1044 { .driver_info = 1 }, /* Matches all devices */
1045 { }, /* Terminating zero entry */
1046};
1047
1048MODULE_DEVICE_TABLE(input, evdev_ids);
1049
1050static struct input_handler evdev_handler = {
1051 .event = evdev_event,
1052 .connect = evdev_connect,
1053 .disconnect = evdev_disconnect,
1054 .fops = &evdev_fops,
1055 .minor = EVDEV_MINOR_BASE,
1056 .name = "evdev",
1057 .id_table = evdev_ids,
1058};
1059
1060static int __init evdev_init(void)
1061{
1062 return input_register_handler(&evdev_handler);
1063}
1064
1065static void __exit evdev_exit(void)
1066{
1067 input_unregister_handler(&evdev_handler);
1068}
1069
1070module_init(evdev_init);
1071module_exit(evdev_exit);
1072
1073MODULE_AUTHOR("Vojtech Pavlik <[email protected]>");
1074MODULE_DESCRIPTION("Input driver event char devices");
1075MODULE_LICENSE("GPL");