Input: evdev - be less aggressive about sending SIGIO notifies
[deliverable/linux.git] / drivers / input / evdev.c
CommitLineData
1da177e4
LT
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>
a99bbaf5 16#include <linux/sched.h>
1da177e4
LT
17#include <linux/slab.h>
18#include <linux/module.h>
19#include <linux/init.h>
20#include <linux/input.h>
21#include <linux/major.h>
1da177e4 22#include <linux/device.h>
2d56f3a3 23#include "input-compat.h"
1da177e4
LT
24
25struct evdev {
26 int exist;
27 int open;
28 int minor;
1da177e4
LT
29 struct input_handle handle;
30 wait_queue_head_t wait;
d0ffb9be
DT
31 struct evdev_client *grab;
32 struct list_head client_list;
6addb1d6
DT
33 spinlock_t client_lock; /* protects client_list */
34 struct mutex mutex;
9657d75c 35 struct device dev;
1da177e4
LT
36};
37
d0ffb9be 38struct evdev_client {
1da177e4
LT
39 struct input_event buffer[EVDEV_BUFFER_SIZE];
40 int head;
41 int tail;
6addb1d6 42 spinlock_t buffer_lock; /* protects access to buffer, head and tail */
1da177e4
LT
43 struct fasync_struct *fasync;
44 struct evdev *evdev;
45 struct list_head node;
46};
47
48static struct evdev *evdev_table[EVDEV_MINORS];
6addb1d6 49static DEFINE_MUTEX(evdev_table_mutex);
1da177e4 50
6addb1d6
DT
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
30a589fd
AJ
62 if (event->type == EV_SYN)
63 kill_fasync(&client->fasync, SIGIO, POLL_IN);
6addb1d6
DT
64}
65
66/*
82ba56c2 67 * Pass incoming event to all connected clients.
6addb1d6
DT
68 */
69static void evdev_event(struct input_handle *handle,
70 unsigned int type, unsigned int code, int value)
1da177e4
LT
71{
72 struct evdev *evdev = handle->private;
d0ffb9be 73 struct evdev_client *client;
6addb1d6 74 struct input_event event;
1da177e4 75
6addb1d6
DT
76 do_gettimeofday(&event.time);
77 event.type = type;
78 event.code = code;
79 event.value = value;
1da177e4 80
82ba56c2
DT
81 rcu_read_lock();
82
6addb1d6
DT
83 client = rcu_dereference(evdev->grab);
84 if (client)
85 evdev_pass_event(client, &event);
86 else
87 list_for_each_entry_rcu(client, &evdev->client_list, node)
88 evdev_pass_event(client, &event);
1da177e4 89
82ba56c2
DT
90 rcu_read_unlock();
91
1da177e4
LT
92 wake_up_interruptible(&evdev->wait);
93}
94
95static int evdev_fasync(int fd, struct file *file, int on)
96{
d0ffb9be 97 struct evdev_client *client = file->private_data;
1e0afb28 98
60aa4924 99 return fasync_helper(fd, file, on, &client->fasync);
1da177e4
LT
100}
101
1e0afb28 102static int evdev_flush(struct file *file, fl_owner_t id)
1da177e4 103{
d0ffb9be
DT
104 struct evdev_client *client = file->private_data;
105 struct evdev *evdev = client->evdev;
6addb1d6
DT
106 int retval;
107
108 retval = mutex_lock_interruptible(&evdev->mutex);
109 if (retval)
110 return retval;
1e0afb28 111
d0ffb9be 112 if (!evdev->exist)
6addb1d6
DT
113 retval = -ENODEV;
114 else
115 retval = input_flush_device(&evdev->handle, file);
1e0afb28 116
6addb1d6
DT
117 mutex_unlock(&evdev->mutex);
118 return retval;
1da177e4
LT
119}
120
9657d75c 121static void evdev_free(struct device *dev)
1da177e4 122{
9657d75c
DT
123 struct evdev *evdev = container_of(dev, struct evdev, dev);
124
a7097ff8 125 input_put_device(evdev->handle.dev);
1da177e4
LT
126 kfree(evdev);
127}
128
6addb1d6
DT
129/*
130 * Grabs an event device (along with underlying input device).
131 * This function is called with evdev->mutex taken.
132 */
133static int evdev_grab(struct evdev *evdev, struct evdev_client *client)
134{
135 int error;
136
137 if (evdev->grab)
138 return -EBUSY;
139
140 error = input_grab_device(&evdev->handle);
141 if (error)
142 return error;
143
144 rcu_assign_pointer(evdev->grab, client);
82ba56c2 145 synchronize_rcu();
6addb1d6
DT
146
147 return 0;
148}
149
150static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client)
151{
152 if (evdev->grab != client)
153 return -EINVAL;
154
155 rcu_assign_pointer(evdev->grab, NULL);
82ba56c2 156 synchronize_rcu();
6addb1d6
DT
157 input_release_device(&evdev->handle);
158
159 return 0;
160}
161
162static void evdev_attach_client(struct evdev *evdev,
163 struct evdev_client *client)
164{
165 spin_lock(&evdev->client_lock);
166 list_add_tail_rcu(&client->node, &evdev->client_list);
167 spin_unlock(&evdev->client_lock);
82ba56c2 168 synchronize_rcu();
6addb1d6
DT
169}
170
171static void evdev_detach_client(struct evdev *evdev,
172 struct evdev_client *client)
173{
174 spin_lock(&evdev->client_lock);
175 list_del_rcu(&client->node);
176 spin_unlock(&evdev->client_lock);
82ba56c2 177 synchronize_rcu();
6addb1d6
DT
178}
179
180static int evdev_open_device(struct evdev *evdev)
181{
182 int retval;
183
184 retval = mutex_lock_interruptible(&evdev->mutex);
185 if (retval)
186 return retval;
187
188 if (!evdev->exist)
189 retval = -ENODEV;
06445014 190 else if (!evdev->open++) {
6addb1d6 191 retval = input_open_device(&evdev->handle);
06445014
ON
192 if (retval)
193 evdev->open--;
194 }
6addb1d6
DT
195
196 mutex_unlock(&evdev->mutex);
197 return retval;
198}
199
200static void evdev_close_device(struct evdev *evdev)
201{
202 mutex_lock(&evdev->mutex);
203
204 if (evdev->exist && !--evdev->open)
205 input_close_device(&evdev->handle);
206
207 mutex_unlock(&evdev->mutex);
208}
209
210/*
211 * Wake up users waiting for IO so they can disconnect from
212 * dead device.
213 */
214static void evdev_hangup(struct evdev *evdev)
215{
216 struct evdev_client *client;
217
218 spin_lock(&evdev->client_lock);
219 list_for_each_entry(client, &evdev->client_list, node)
220 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
221 spin_unlock(&evdev->client_lock);
222
223 wake_up_interruptible(&evdev->wait);
224}
225
d0ffb9be 226static int evdev_release(struct inode *inode, struct file *file)
1da177e4 227{
d0ffb9be
DT
228 struct evdev_client *client = file->private_data;
229 struct evdev *evdev = client->evdev;
1da177e4 230
6addb1d6
DT
231 mutex_lock(&evdev->mutex);
232 if (evdev->grab == client)
233 evdev_ungrab(evdev, client);
234 mutex_unlock(&evdev->mutex);
1da177e4 235
6addb1d6 236 evdev_detach_client(evdev, client);
d0ffb9be 237 kfree(client);
1da177e4 238
6addb1d6 239 evdev_close_device(evdev);
9657d75c 240 put_device(&evdev->dev);
1da177e4 241
1da177e4
LT
242 return 0;
243}
244
d0ffb9be 245static int evdev_open(struct inode *inode, struct file *file)
1da177e4 246{
d0ffb9be 247 struct evdev *evdev;
6addb1d6 248 struct evdev_client *client;
1da177e4 249 int i = iminor(inode) - EVDEV_MINOR_BASE;
d542ed82 250 int error;
1da177e4 251
d0ffb9be 252 if (i >= EVDEV_MINORS)
1da177e4
LT
253 return -ENODEV;
254
6addb1d6
DT
255 error = mutex_lock_interruptible(&evdev_table_mutex);
256 if (error)
257 return error;
d0ffb9be 258 evdev = evdev_table[i];
6addb1d6
DT
259 if (evdev)
260 get_device(&evdev->dev);
261 mutex_unlock(&evdev_table_mutex);
d0ffb9be 262
6addb1d6 263 if (!evdev)
1da177e4
LT
264 return -ENODEV;
265
d0ffb9be 266 client = kzalloc(sizeof(struct evdev_client), GFP_KERNEL);
9657d75c
DT
267 if (!client) {
268 error = -ENOMEM;
269 goto err_put_evdev;
270 }
1da177e4 271
6addb1d6 272 spin_lock_init(&client->buffer_lock);
d0ffb9be 273 client->evdev = evdev;
6addb1d6 274 evdev_attach_client(evdev, client);
1da177e4 275
6addb1d6
DT
276 error = evdev_open_device(evdev);
277 if (error)
278 goto err_free_client;
1da177e4 279
d0ffb9be 280 file->private_data = client;
1da177e4 281 return 0;
9657d75c
DT
282
283 err_free_client:
6addb1d6 284 evdev_detach_client(evdev, client);
9657d75c
DT
285 kfree(client);
286 err_put_evdev:
287 put_device(&evdev->dev);
288 return error;
1da177e4
LT
289}
290
6addb1d6
DT
291static ssize_t evdev_write(struct file *file, const char __user *buffer,
292 size_t count, loff_t *ppos)
3a51f7c4 293{
d0ffb9be
DT
294 struct evdev_client *client = file->private_data;
295 struct evdev *evdev = client->evdev;
3a51f7c4 296 struct input_event event;
6addb1d6 297 int retval;
52658bb6 298
6addb1d6
DT
299 retval = mutex_lock_interruptible(&evdev->mutex);
300 if (retval)
301 return retval;
302
303 if (!evdev->exist) {
304 retval = -ENODEV;
305 goto out;
306 }
52658bb6 307
3a51f7c4
DT
308 while (retval < count) {
309
2d56f3a3 310 if (input_event_from_user(buffer + retval, &event)) {
6addb1d6
DT
311 retval = -EFAULT;
312 goto out;
313 }
314
315 input_inject_event(&evdev->handle,
316 event.type, event.code, event.value);
2d56f3a3 317 retval += input_event_size();
52658bb6
JK
318 }
319
6addb1d6
DT
320 out:
321 mutex_unlock(&evdev->mutex);
52658bb6
JK
322 return retval;
323}
52658bb6 324
6addb1d6
DT
325static int evdev_fetch_next_event(struct evdev_client *client,
326 struct input_event *event)
327{
328 int have_event;
329
330 spin_lock_irq(&client->buffer_lock);
331
332 have_event = client->head != client->tail;
333 if (have_event) {
334 *event = client->buffer[client->tail++];
335 client->tail &= EVDEV_BUFFER_SIZE - 1;
336 }
337
338 spin_unlock_irq(&client->buffer_lock);
339
340 return have_event;
341}
342
343static ssize_t evdev_read(struct file *file, char __user *buffer,
344 size_t count, loff_t *ppos)
1da177e4 345{
d0ffb9be
DT
346 struct evdev_client *client = file->private_data;
347 struct evdev *evdev = client->evdev;
6addb1d6 348 struct input_event event;
1da177e4
LT
349 int retval;
350
2d56f3a3 351 if (count < input_event_size())
1da177e4
LT
352 return -EINVAL;
353
6addb1d6
DT
354 if (client->head == client->tail && evdev->exist &&
355 (file->f_flags & O_NONBLOCK))
1da177e4
LT
356 return -EAGAIN;
357
d0ffb9be
DT
358 retval = wait_event_interruptible(evdev->wait,
359 client->head != client->tail || !evdev->exist);
1da177e4
LT
360 if (retval)
361 return retval;
362
d0ffb9be 363 if (!evdev->exist)
1da177e4
LT
364 return -ENODEV;
365
2d56f3a3 366 while (retval + input_event_size() <= count &&
6addb1d6 367 evdev_fetch_next_event(client, &event)) {
3a51f7c4 368
2d56f3a3 369 if (input_event_to_user(buffer + retval, &event))
3a51f7c4
DT
370 return -EFAULT;
371
2d56f3a3 372 retval += input_event_size();
1da177e4
LT
373 }
374
375 return retval;
376}
377
378/* No kernel lock - fine */
379static unsigned int evdev_poll(struct file *file, poll_table *wait)
380{
d0ffb9be
DT
381 struct evdev_client *client = file->private_data;
382 struct evdev *evdev = client->evdev;
1e0afb28 383
d0ffb9be
DT
384 poll_wait(file, &evdev->wait, wait);
385 return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) |
386 (evdev->exist ? 0 : (POLLHUP | POLLERR));
1da177e4
LT
387}
388
3a51f7c4
DT
389#ifdef CONFIG_COMPAT
390
391#define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
7b19ada2 392#define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
3a51f7c4
DT
393
394#ifdef __BIG_ENDIAN
395static int bits_to_user(unsigned long *bits, unsigned int maxbit,
396 unsigned int maxlen, void __user *p, int compat)
397{
398 int len, i;
399
400 if (compat) {
7b19ada2 401 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t);
bf61f8d3 402 if (len > maxlen)
3a51f7c4
DT
403 len = maxlen;
404
405 for (i = 0; i < len / sizeof(compat_long_t); i++)
406 if (copy_to_user((compat_long_t __user *) p + i,
407 (compat_long_t *) bits +
408 i + 1 - ((i % 2) << 1),
409 sizeof(compat_long_t)))
410 return -EFAULT;
411 } else {
7b19ada2 412 len = BITS_TO_LONGS(maxbit) * sizeof(long);
3a51f7c4
DT
413 if (len > maxlen)
414 len = maxlen;
415
416 if (copy_to_user(p, bits, len))
417 return -EFAULT;
418 }
419
420 return len;
421}
422#else
423static int bits_to_user(unsigned long *bits, unsigned int maxbit,
424 unsigned int maxlen, void __user *p, int compat)
425{
426 int len = compat ?
7b19ada2
JS
427 BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) :
428 BITS_TO_LONGS(maxbit) * sizeof(long);
3a51f7c4
DT
429
430 if (len > maxlen)
431 len = maxlen;
432
433 return copy_to_user(p, bits, len) ? -EFAULT : len;
434}
435#endif /* __BIG_ENDIAN */
436
437#else
438
439static int bits_to_user(unsigned long *bits, unsigned int maxbit,
440 unsigned int maxlen, void __user *p, int compat)
441{
7b19ada2 442 int len = BITS_TO_LONGS(maxbit) * sizeof(long);
3a51f7c4
DT
443
444 if (len > maxlen)
445 len = maxlen;
446
447 return copy_to_user(p, bits, len) ? -EFAULT : len;
448}
449
450#endif /* CONFIG_COMPAT */
451
452static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
453{
454 int len;
455
456 if (!str)
457 return -ENOENT;
458
459 len = strlen(str) + 1;
460 if (len > maxlen)
461 len = maxlen;
462
463 return copy_to_user(p, str, len) ? -EFAULT : len;
464}
465
f2afa771 466#define OLD_KEY_MAX 0x1ff
5402a734
LT
467static int handle_eviocgbit(struct input_dev *dev, unsigned int cmd, void __user *p, int compat_mode)
468{
f2afa771 469 static unsigned long keymax_warn_time;
5402a734
LT
470 unsigned long *bits;
471 int len;
472
473 switch (_IOC_NR(cmd) & EV_MAX) {
474
475 case 0: bits = dev->evbit; len = EV_MAX; break;
476 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
477 case EV_REL: bits = dev->relbit; len = REL_MAX; break;
478 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
479 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
480 case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
481 case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
482 case EV_FF: bits = dev->ffbit; len = FF_MAX; break;
483 case EV_SW: bits = dev->swbit; len = SW_MAX; break;
484 default: return -EINVAL;
485 }
f2afa771
DT
486
487 /*
488 * Work around bugs in userspace programs that like to do
489 * EVIOCGBIT(EV_KEY, KEY_MAX) and not realize that 'len'
490 * should be in bytes, not in bits.
491 */
492 if ((_IOC_NR(cmd) & EV_MAX) == EV_KEY && _IOC_SIZE(cmd) == OLD_KEY_MAX) {
493 len = OLD_KEY_MAX;
494 if (printk_timed_ratelimit(&keymax_warn_time, 10 * 1000))
495 printk(KERN_WARNING
c85e2031
GU
496 "evdev.c(EVIOCGBIT): Suspicious buffer size %u, "
497 "limiting output to %zu bytes. See "
f2afa771
DT
498 "http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n",
499 OLD_KEY_MAX,
500 BITS_TO_LONGS(OLD_KEY_MAX) * sizeof(long));
501 }
502
5402a734
LT
503 return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode);
504}
f2afa771 505#undef OLD_KEY_MAX
5402a734 506
6addb1d6
DT
507static long evdev_do_ioctl(struct file *file, unsigned int cmd,
508 void __user *p, int compat_mode)
1da177e4 509{
d0ffb9be
DT
510 struct evdev_client *client = file->private_data;
511 struct evdev *evdev = client->evdev;
1da177e4
LT
512 struct input_dev *dev = evdev->handle.dev;
513 struct input_absinfo abs;
509ca1a9 514 struct ff_effect effect;
3a51f7c4 515 int __user *ip = (int __user *)p;
1da177e4 516 int i, t, u, v;
509ca1a9 517 int error;
1da177e4 518
1da177e4
LT
519 switch (cmd) {
520
6addb1d6
DT
521 case EVIOCGVERSION:
522 return put_user(EV_VERSION, ip);
1da177e4 523
6addb1d6
DT
524 case EVIOCGID:
525 if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
526 return -EFAULT;
527 return 0;
08791e5c 528
6addb1d6
DT
529 case EVIOCGREP:
530 if (!test_bit(EV_REP, dev->evbit))
531 return -ENOSYS;
532 if (put_user(dev->rep[REP_DELAY], ip))
533 return -EFAULT;
534 if (put_user(dev->rep[REP_PERIOD], ip + 1))
535 return -EFAULT;
536 return 0;
08791e5c 537
6addb1d6
DT
538 case EVIOCSREP:
539 if (!test_bit(EV_REP, dev->evbit))
540 return -ENOSYS;
541 if (get_user(u, ip))
542 return -EFAULT;
543 if (get_user(v, ip + 1))
544 return -EFAULT;
08791e5c 545
6addb1d6
DT
546 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
547 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
3a51f7c4 548
6addb1d6 549 return 0;
1da177e4 550
6addb1d6
DT
551 case EVIOCGKEYCODE:
552 if (get_user(t, ip))
553 return -EFAULT;
c8e4c772 554
f4f37c8e 555 error = input_get_keycode(dev, t, &v);
6addb1d6
DT
556 if (error)
557 return error;
c8e4c772 558
6addb1d6
DT
559 if (put_user(v, ip + 1))
560 return -EFAULT;
c8e4c772 561
6addb1d6 562 return 0;
1da177e4 563
6addb1d6
DT
564 case EVIOCSKEYCODE:
565 if (get_user(t, ip) || get_user(v, ip + 1))
566 return -EFAULT;
3a51f7c4 567
f4f37c8e 568 return input_set_keycode(dev, t, v);
1da177e4 569
6addb1d6
DT
570 case EVIOCRMFF:
571 return input_ff_erase(dev, (int)(unsigned long) p, file);
1da177e4 572
6addb1d6
DT
573 case EVIOCGEFFECTS:
574 i = test_bit(EV_FF, dev->evbit) ?
575 dev->ff->max_effects : 0;
576 if (put_user(i, ip))
577 return -EFAULT;
578 return 0;
579
580 case EVIOCGRAB:
581 if (p)
582 return evdev_grab(evdev, client);
583 else
584 return evdev_ungrab(evdev, client);
1da177e4 585
6addb1d6 586 default:
1da177e4 587
6addb1d6
DT
588 if (_IOC_TYPE(cmd) != 'E')
589 return -EINVAL;
1da177e4 590
6addb1d6 591 if (_IOC_DIR(cmd) == _IOC_READ) {
41e979f8 592
5402a734
LT
593 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0)))
594 return handle_eviocgbit(dev, cmd, p, compat_mode);
1da177e4 595
6addb1d6
DT
596 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
597 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd),
598 p, compat_mode);
1da177e4 599
6addb1d6
DT
600 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
601 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd),
602 p, compat_mode);
1da177e4 603
6addb1d6
DT
604 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
605 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd),
606 p, compat_mode);
31581066 607
6addb1d6
DT
608 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0)))
609 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd),
610 p, compat_mode);
1da177e4 611
6addb1d6 612 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0)))
f9366014 613 return str_to_user(dev->name, _IOC_SIZE(cmd), p);
1da177e4 614
6addb1d6
DT
615 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0)))
616 return str_to_user(dev->phys, _IOC_SIZE(cmd), p);
1da177e4 617
6addb1d6
DT
618 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0)))
619 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p);
1da177e4 620
6addb1d6 621 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
1da177e4 622
6addb1d6 623 t = _IOC_NR(cmd) & ABS_MAX;
1da177e4 624
6addb1d6
DT
625 abs.value = dev->abs[t];
626 abs.minimum = dev->absmin[t];
627 abs.maximum = dev->absmax[t];
628 abs.fuzz = dev->absfuzz[t];
629 abs.flat = dev->absflat[t];
ec20a022 630 abs.resolution = dev->absres[t];
41e979f8 631
ec20a022
TS
632 if (copy_to_user(p, &abs, min_t(size_t,
633 _IOC_SIZE(cmd),
634 sizeof(struct input_absinfo))))
6addb1d6 635 return -EFAULT;
1da177e4 636
6addb1d6 637 return 0;
1da177e4
LT
638 }
639
6addb1d6
DT
640 }
641
642 if (_IOC_DIR(cmd) == _IOC_WRITE) {
1da177e4 643
f2278f31
AD
644 if (_IOC_NR(cmd) == _IOC_NR(EVIOCSFF)) {
645
2d56f3a3 646 if (input_ff_effect_from_user(p, _IOC_SIZE(cmd), &effect))
f2278f31
AD
647 return -EFAULT;
648
649 error = input_ff_upload(dev, &effect, file);
650
651 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
652 return -EFAULT;
653
654 return error;
655 }
656
6addb1d6 657 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
1da177e4 658
6addb1d6 659 t = _IOC_NR(cmd) & ABS_MAX;
41e979f8 660
ec20a022
TS
661 if (copy_from_user(&abs, p, min_t(size_t,
662 _IOC_SIZE(cmd),
663 sizeof(struct input_absinfo))))
6addb1d6 664 return -EFAULT;
1da177e4 665
6addb1d6
DT
666 /*
667 * Take event lock to ensure that we are not
668 * changing device parameters in the middle
669 * of event.
670 */
671 spin_lock_irq(&dev->event_lock);
1da177e4 672
6addb1d6
DT
673 dev->abs[t] = abs.value;
674 dev->absmin[t] = abs.minimum;
675 dev->absmax[t] = abs.maximum;
676 dev->absfuzz[t] = abs.fuzz;
677 dev->absflat[t] = abs.flat;
ec20a022
TS
678 dev->absres[t] = _IOC_SIZE(cmd) < sizeof(struct input_absinfo) ?
679 0 : abs.resolution;
6addb1d6
DT
680
681 spin_unlock_irq(&dev->event_lock);
682
683 return 0;
1da177e4 684 }
6addb1d6 685 }
1da177e4
LT
686 }
687 return -EINVAL;
688}
1da177e4 689
6addb1d6
DT
690static long evdev_ioctl_handler(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 int retval;
696
697 retval = mutex_lock_interruptible(&evdev->mutex);
698 if (retval)
699 return retval;
700
701 if (!evdev->exist) {
702 retval = -ENODEV;
703 goto out;
704 }
705
706 retval = evdev_do_ioctl(file, cmd, p, compat_mode);
707
708 out:
709 mutex_unlock(&evdev->mutex);
710 return retval;
711}
712
3a51f7c4
DT
713static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
714{
715 return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
716}
41e979f8 717
3a51f7c4 718#ifdef CONFIG_COMPAT
6addb1d6
DT
719static long evdev_ioctl_compat(struct file *file,
720 unsigned int cmd, unsigned long arg)
52658bb6 721{
3a51f7c4 722 return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
1da177e4 723}
52658bb6 724#endif
1da177e4 725
66e66118 726static const struct file_operations evdev_fops = {
6addb1d6
DT
727 .owner = THIS_MODULE,
728 .read = evdev_read,
729 .write = evdev_write,
730 .poll = evdev_poll,
731 .open = evdev_open,
732 .release = evdev_release,
733 .unlocked_ioctl = evdev_ioctl,
52658bb6 734#ifdef CONFIG_COMPAT
6addb1d6 735 .compat_ioctl = evdev_ioctl_compat,
52658bb6 736#endif
6addb1d6
DT
737 .fasync = evdev_fasync,
738 .flush = evdev_flush
1da177e4
LT
739};
740
6addb1d6
DT
741static int evdev_install_chrdev(struct evdev *evdev)
742{
743 /*
744 * No need to do any locking here as calls to connect and
745 * disconnect are serialized by the input core
746 */
747 evdev_table[evdev->minor] = evdev;
748 return 0;
749}
750
751static void evdev_remove_chrdev(struct evdev *evdev)
752{
753 /*
754 * Lock evdev table to prevent race with evdev_open()
755 */
756 mutex_lock(&evdev_table_mutex);
757 evdev_table[evdev->minor] = NULL;
758 mutex_unlock(&evdev_table_mutex);
759}
760
761/*
762 * Mark device non-existent. This disables writes, ioctls and
763 * prevents new users from opening the device. Already posted
764 * blocking reads will stay, however new ones will fail.
765 */
766static void evdev_mark_dead(struct evdev *evdev)
767{
768 mutex_lock(&evdev->mutex);
769 evdev->exist = 0;
770 mutex_unlock(&evdev->mutex);
771}
772
773static void evdev_cleanup(struct evdev *evdev)
774{
775 struct input_handle *handle = &evdev->handle;
776
777 evdev_mark_dead(evdev);
778 evdev_hangup(evdev);
779 evdev_remove_chrdev(evdev);
780
781 /* evdev is marked dead so no one else accesses evdev->open */
782 if (evdev->open) {
783 input_flush_device(handle, NULL);
784 input_close_device(handle);
785 }
786}
787
788/*
789 * Create new evdev device. Note that input core serializes calls
790 * to connect and disconnect so we don't need to lock evdev_table here.
791 */
5b2a0826
DT
792static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
793 const struct input_device_id *id)
1da177e4
LT
794{
795 struct evdev *evdev;
796 int minor;
5b2a0826 797 int error;
1da177e4 798
6addb1d6
DT
799 for (minor = 0; minor < EVDEV_MINORS; minor++)
800 if (!evdev_table[minor])
801 break;
802
1da177e4
LT
803 if (minor == EVDEV_MINORS) {
804 printk(KERN_ERR "evdev: no more free evdev devices\n");
5b2a0826 805 return -ENFILE;
1da177e4
LT
806 }
807
5b2a0826
DT
808 evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
809 if (!evdev)
810 return -ENOMEM;
1da177e4 811
d0ffb9be 812 INIT_LIST_HEAD(&evdev->client_list);
6addb1d6
DT
813 spin_lock_init(&evdev->client_lock);
814 mutex_init(&evdev->mutex);
1da177e4
LT
815 init_waitqueue_head(&evdev->wait);
816
3d5cb60e 817 dev_set_name(&evdev->dev, "event%d", minor);
1da177e4
LT
818 evdev->exist = 1;
819 evdev->minor = minor;
6addb1d6 820
a7097ff8 821 evdev->handle.dev = input_get_device(dev);
3d5cb60e 822 evdev->handle.name = dev_name(&evdev->dev);
1da177e4
LT
823 evdev->handle.handler = handler;
824 evdev->handle.private = evdev;
1da177e4 825
6addb1d6 826 evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor);
9657d75c
DT
827 evdev->dev.class = &input_class;
828 evdev->dev.parent = &dev->dev;
9657d75c
DT
829 evdev->dev.release = evdev_free;
830 device_initialize(&evdev->dev);
5b2a0826 831
6addb1d6 832 error = input_register_handle(&evdev->handle);
5b2a0826 833 if (error)
9657d75c 834 goto err_free_evdev;
5b2a0826 835
6addb1d6
DT
836 error = evdev_install_chrdev(evdev);
837 if (error)
838 goto err_unregister_handle;
839
840 error = device_add(&evdev->dev);
5b2a0826 841 if (error)
6addb1d6 842 goto err_cleanup_evdev;
1da177e4 843
5b2a0826 844 return 0;
1da177e4 845
6addb1d6
DT
846 err_cleanup_evdev:
847 evdev_cleanup(evdev);
848 err_unregister_handle:
849 input_unregister_handle(&evdev->handle);
5b2a0826 850 err_free_evdev:
9657d75c 851 put_device(&evdev->dev);
5b2a0826 852 return error;
1da177e4
LT
853}
854
855static void evdev_disconnect(struct input_handle *handle)
856{
857 struct evdev *evdev = handle->private;
1da177e4 858
9657d75c 859 device_del(&evdev->dev);
6addb1d6
DT
860 evdev_cleanup(evdev);
861 input_unregister_handle(handle);
9657d75c 862 put_device(&evdev->dev);
1da177e4
LT
863}
864
66e66118 865static const struct input_device_id evdev_ids[] = {
1da177e4
LT
866 { .driver_info = 1 }, /* Matches all devices */
867 { }, /* Terminating zero entry */
868};
869
870MODULE_DEVICE_TABLE(input, evdev_ids);
871
872static struct input_handler evdev_handler = {
6addb1d6
DT
873 .event = evdev_event,
874 .connect = evdev_connect,
875 .disconnect = evdev_disconnect,
876 .fops = &evdev_fops,
877 .minor = EVDEV_MINOR_BASE,
878 .name = "evdev",
879 .id_table = evdev_ids,
1da177e4
LT
880};
881
882static int __init evdev_init(void)
883{
4263cf0f 884 return input_register_handler(&evdev_handler);
1da177e4
LT
885}
886
887static void __exit evdev_exit(void)
888{
889 input_unregister_handler(&evdev_handler);
890}
891
892module_init(evdev_init);
893module_exit(evdev_exit);
894
895MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
896MODULE_DESCRIPTION("Input driver event char devices");
897MODULE_LICENSE("GPL");
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