projects/linux·blob v2.6.23-rc2 · refs

741 lines · 17.2 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 struct device dev;
34};
35
36struct evdev_client {
37 struct input_event buffer[EVDEV_BUFFER_SIZE];
38 int head;
39 int tail;
40 struct fasync_struct *fasync;
41 struct evdev *evdev;
42 struct list_head node;
43};
44
45static struct evdev *evdev_table[EVDEV_MINORS];
46
47static void evdev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
48{
49 struct evdev *evdev = handle->private;
50 struct evdev_client *client;
51
52 if (evdev->grab) {
53 client = evdev->grab;
54
55 do_gettimeofday(&client->buffer[client->head].time);
56 client->buffer[client->head].type = type;
57 client->buffer[client->head].code = code;
58 client->buffer[client->head].value = value;
59 client->head = (client->head + 1) & (EVDEV_BUFFER_SIZE - 1);
60
61 kill_fasync(&client->fasync, SIGIO, POLL_IN);
62 } else
63 list_for_each_entry(client, &evdev->client_list, node) {
64
65 do_gettimeofday(&client->buffer[client->head].time);
66 client->buffer[client->head].type = type;
67 client->buffer[client->head].code = code;
68 client->buffer[client->head].value = value;
69 client->head = (client->head + 1) & (EVDEV_BUFFER_SIZE - 1);
70
71 kill_fasync(&client->fasync, SIGIO, POLL_IN);
72 }
73
74 wake_up_interruptible(&evdev->wait);
75}
76
77static int evdev_fasync(int fd, struct file *file, int on)
78{
79 struct evdev_client *client = file->private_data;
80 int retval;
81
82 retval = fasync_helper(fd, file, on, &client->fasync);
83
84 return retval < 0 ? retval : 0;
85}
86
87static int evdev_flush(struct file *file, fl_owner_t id)
88{
89 struct evdev_client *client = file->private_data;
90 struct evdev *evdev = client->evdev;
91
92 if (!evdev->exist)
93 return -ENODEV;
94
95 return input_flush_device(&evdev->handle, file);
96}
97
98static void evdev_free(struct device *dev)
99{
100 struct evdev *evdev = container_of(dev, struct evdev, dev);
101
102 evdev_table[evdev->minor] = NULL;
103 kfree(evdev);
104}
105
106static int evdev_release(struct inode *inode, struct file *file)
107{
108 struct evdev_client *client = file->private_data;
109 struct evdev *evdev = client->evdev;
110
111 if (evdev->grab == client) {
112 input_release_device(&evdev->handle);
113 evdev->grab = NULL;
114 }
115
116 evdev_fasync(-1, file, 0);
117 list_del(&client->node);
118 kfree(client);
119
120 if (!--evdev->open && evdev->exist)
121 input_close_device(&evdev->handle);
122
123 put_device(&evdev->dev);
124
125 return 0;
126}
127
128static int evdev_open(struct inode *inode, struct file *file)
129{
130 struct evdev_client *client;
131 struct evdev *evdev;
132 int i = iminor(inode) - EVDEV_MINOR_BASE;
133 int error;
134
135 if (i >= EVDEV_MINORS)
136 return -ENODEV;
137
138 evdev = evdev_table[i];
139
140 if (!evdev || !evdev->exist)
141 return -ENODEV;
142
143 get_device(&evdev->dev);
144
145 client = kzalloc(sizeof(struct evdev_client), GFP_KERNEL);
146 if (!client) {
147 error = -ENOMEM;
148 goto err_put_evdev;
149 }
150
151 client->evdev = evdev;
152 list_add_tail(&client->node, &evdev->client_list);
153
154 if (!evdev->open++ && evdev->exist) {
155 error = input_open_device(&evdev->handle);
156 if (error)
157 goto err_free_client;
158 }
159
160 file->private_data = client;
161 return 0;
162
163 err_free_client:
164 list_del(&client->node);
165 kfree(client);
166 err_put_evdev:
167 put_device(&evdev->dev);
168 return error;
169}
170
171#ifdef CONFIG_COMPAT
172
173struct input_event_compat {
174 struct compat_timeval time;
175 __u16 type;
176 __u16 code;
177 __s32 value;
178};
179
180/* Note to the author of this code: did it ever occur to
181 you why the ifdefs are needed? Think about it again. -AK */
182#ifdef CONFIG_X86_64
183# define COMPAT_TEST is_compat_task()
184#elif defined(CONFIG_IA64)
185# define COMPAT_TEST IS_IA32_PROCESS(task_pt_regs(current))
186#elif defined(CONFIG_S390)
187# define COMPAT_TEST test_thread_flag(TIF_31BIT)
188#elif defined(CONFIG_MIPS)
189# define COMPAT_TEST test_thread_flag(TIF_32BIT_ADDR)
190#else
191# define COMPAT_TEST test_thread_flag(TIF_32BIT)
192#endif
193
194static inline size_t evdev_event_size(void)
195{
196 return COMPAT_TEST ?
197 sizeof(struct input_event_compat) : sizeof(struct input_event);
198}
199
200static int evdev_event_from_user(const char __user *buffer, struct input_event *event)
201{
202 if (COMPAT_TEST) {
203 struct input_event_compat compat_event;
204
205 if (copy_from_user(&compat_event, buffer, sizeof(struct input_event_compat)))
206 return -EFAULT;
207
208 event->time.tv_sec = compat_event.time.tv_sec;
209 event->time.tv_usec = compat_event.time.tv_usec;
210 event->type = compat_event.type;
211 event->code = compat_event.code;
212 event->value = compat_event.value;
213
214 } else {
215 if (copy_from_user(event, buffer, sizeof(struct input_event)))
216 return -EFAULT;
217 }
218
219 return 0;
220}
221
222static int evdev_event_to_user(char __user *buffer, const struct input_event *event)
223{
224 if (COMPAT_TEST) {
225 struct input_event_compat compat_event;
226
227 compat_event.time.tv_sec = event->time.tv_sec;
228 compat_event.time.tv_usec = event->time.tv_usec;
229 compat_event.type = event->type;
230 compat_event.code = event->code;
231 compat_event.value = event->value;
232
233 if (copy_to_user(buffer, &compat_event, sizeof(struct input_event_compat)))
234 return -EFAULT;
235
236 } else {
237 if (copy_to_user(buffer, event, sizeof(struct input_event)))
238 return -EFAULT;
239 }
240
241 return 0;
242}
243
244#else
245
246static inline size_t evdev_event_size(void)
247{
248 return sizeof(struct input_event);
249}
250
251static int evdev_event_from_user(const char __user *buffer, struct input_event *event)
252{
253 if (copy_from_user(event, buffer, sizeof(struct input_event)))
254 return -EFAULT;
255
256 return 0;
257}
258
259static int evdev_event_to_user(char __user *buffer, const struct input_event *event)
260{
261 if (copy_to_user(buffer, event, sizeof(struct input_event)))
262 return -EFAULT;
263
264 return 0;
265}
266
267#endif /* CONFIG_COMPAT */
268
269static ssize_t evdev_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
270{
271 struct evdev_client *client = file->private_data;
272 struct evdev *evdev = client->evdev;
273 struct input_event event;
274 int retval = 0;
275
276 if (!evdev->exist)
277 return -ENODEV;
278
279 while (retval < count) {
280
281 if (evdev_event_from_user(buffer + retval, &event))
282 return -EFAULT;
283 input_inject_event(&evdev->handle, event.type, event.code, event.value);
284 retval += evdev_event_size();
285 }
286
287 return retval;
288}
289
290static ssize_t evdev_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
291{
292 struct evdev_client *client = file->private_data;
293 struct evdev *evdev = client->evdev;
294 int retval;
295
296 if (count < evdev_event_size())
297 return -EINVAL;
298
299 if (client->head == client->tail && evdev->exist && (file->f_flags & O_NONBLOCK))
300 return -EAGAIN;
301
302 retval = wait_event_interruptible(evdev->wait,
303 client->head != client->tail || !evdev->exist);
304 if (retval)
305 return retval;
306
307 if (!evdev->exist)
308 return -ENODEV;
309
310 while (client->head != client->tail && retval + evdev_event_size() <= count) {
311
312 struct input_event *event = (struct input_event *) client->buffer + client->tail;
313
314 if (evdev_event_to_user(buffer + retval, event))
315 return -EFAULT;
316
317 client->tail = (client->tail + 1) & (EVDEV_BUFFER_SIZE - 1);
318 retval += evdev_event_size();
319 }
320
321 return retval;
322}
323
324/* No kernel lock - fine */
325static unsigned int evdev_poll(struct file *file, poll_table *wait)
326{
327 struct evdev_client *client = file->private_data;
328 struct evdev *evdev = client->evdev;
329
330 poll_wait(file, &evdev->wait, wait);
331 return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) |
332 (evdev->exist ? 0 : (POLLHUP | POLLERR));
333}
334
335#ifdef CONFIG_COMPAT
336
337#define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
338#define NBITS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
339
340#ifdef __BIG_ENDIAN
341static int bits_to_user(unsigned long *bits, unsigned int maxbit,
342 unsigned int maxlen, void __user *p, int compat)
343{
344 int len, i;
345
346 if (compat) {
347 len = NBITS_COMPAT(maxbit) * sizeof(compat_long_t);
348 if (len > maxlen)
349 len = maxlen;
350
351 for (i = 0; i < len / sizeof(compat_long_t); i++)
352 if (copy_to_user((compat_long_t __user *) p + i,
353 (compat_long_t *) bits +
354 i + 1 - ((i % 2) << 1),
355 sizeof(compat_long_t)))
356 return -EFAULT;
357 } else {
358 len = NBITS(maxbit) * sizeof(long);
359 if (len > maxlen)
360 len = maxlen;
361
362 if (copy_to_user(p, bits, len))
363 return -EFAULT;
364 }
365
366 return len;
367}
368#else
369static int bits_to_user(unsigned long *bits, unsigned int maxbit,
370 unsigned int maxlen, void __user *p, int compat)
371{
372 int len = compat ?
373 NBITS_COMPAT(maxbit) * sizeof(compat_long_t) :
374 NBITS(maxbit) * sizeof(long);
375
376 if (len > maxlen)
377 len = maxlen;
378
379 return copy_to_user(p, bits, len) ? -EFAULT : len;
380}
381#endif /* __BIG_ENDIAN */
382
383#else
384
385static int bits_to_user(unsigned long *bits, unsigned int maxbit,
386 unsigned int maxlen, void __user *p, int compat)
387{
388 int len = NBITS(maxbit) * sizeof(long);
389
390 if (len > maxlen)
391 len = maxlen;
392
393 return copy_to_user(p, bits, len) ? -EFAULT : len;
394}
395
396#endif /* CONFIG_COMPAT */
397
398static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
399{
400 int len;
401
402 if (!str)
403 return -ENOENT;
404
405 len = strlen(str) + 1;
406 if (len > maxlen)
407 len = maxlen;
408
409 return copy_to_user(p, str, len) ? -EFAULT : len;
410}
411
412static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
413 void __user *p, int compat_mode)
414{
415 struct evdev_client *client = file->private_data;
416 struct evdev *evdev = client->evdev;
417 struct input_dev *dev = evdev->handle.dev;
418 struct input_absinfo abs;
419 struct ff_effect effect;
420 int __user *ip = (int __user *)p;
421 int i, t, u, v;
422 int error;
423
424 if (!evdev->exist)
425 return -ENODEV;
426
427 switch (cmd) {
428
429 case EVIOCGVERSION:
430 return put_user(EV_VERSION, ip);
431
432 case EVIOCGID:
433 if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
434 return -EFAULT;
435 return 0;
436
437 case EVIOCGREP:
438 if (!test_bit(EV_REP, dev->evbit))
439 return -ENOSYS;
440 if (put_user(dev->rep[REP_DELAY], ip))
441 return -EFAULT;
442 if (put_user(dev->rep[REP_PERIOD], ip + 1))
443 return -EFAULT;
444 return 0;
445
446 case EVIOCSREP:
447 if (!test_bit(EV_REP, dev->evbit))
448 return -ENOSYS;
449 if (get_user(u, ip))
450 return -EFAULT;
451 if (get_user(v, ip + 1))
452 return -EFAULT;
453
454 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
455 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
456
457 return 0;
458
459 case EVIOCGKEYCODE:
460 if (get_user(t, ip))
461 return -EFAULT;
462
463 error = dev->getkeycode(dev, t, &v);
464 if (error)
465 return error;
466
467 if (put_user(v, ip + 1))
468 return -EFAULT;
469
470 return 0;
471
472 case EVIOCSKEYCODE:
473 if (get_user(t, ip) || get_user(v, ip + 1))
474 return -EFAULT;
475
476 return dev->setkeycode(dev, t, v);
477
478 case EVIOCSFF:
479 if (copy_from_user(&effect, p, sizeof(effect)))
480 return -EFAULT;
481
482 error = input_ff_upload(dev, &effect, file);
483
484 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
485 return -EFAULT;
486
487 return error;
488
489 case EVIOCRMFF:
490 return input_ff_erase(dev, (int)(unsigned long) p, file);
491
492 case EVIOCGEFFECTS:
493 i = test_bit(EV_FF, dev->evbit) ? dev->ff->max_effects : 0;
494 if (put_user(i, ip))
495 return -EFAULT;
496 return 0;
497
498 case EVIOCGRAB:
499 if (p) {
500 if (evdev->grab)
501 return -EBUSY;
502 if (input_grab_device(&evdev->handle))
503 return -EBUSY;
504 evdev->grab = client;
505 return 0;
506 } else {
507 if (evdev->grab != client)
508 return -EINVAL;
509 input_release_device(&evdev->handle);
510 evdev->grab = NULL;
511 return 0;
512 }
513
514 default:
515
516 if (_IOC_TYPE(cmd) != 'E')
517 return -EINVAL;
518
519 if (_IOC_DIR(cmd) == _IOC_READ) {
520
521 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) {
522
523 unsigned long *bits;
524 int len;
525
526 switch (_IOC_NR(cmd) & EV_MAX) {
527 case 0: bits = dev->evbit; len = EV_MAX; break;
528 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
529 case EV_REL: bits = dev->relbit; len = REL_MAX; break;
530 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
531 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
532 case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
533 case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
534 case EV_FF: bits = dev->ffbit; len = FF_MAX; break;
535 case EV_SW: bits = dev->swbit; len = SW_MAX; break;
536 default: return -EINVAL;
537 }
538 return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode);
539 }
540
541 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
542 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd),
543 p, compat_mode);
544
545 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
546 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd),
547 p, compat_mode);
548
549 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
550 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd),
551 p, compat_mode);
552
553 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0)))
554 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd),
555 p, compat_mode);
556
557 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0)))
558 return str_to_user(dev->name, _IOC_SIZE(cmd), p);
559
560 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0)))
561 return str_to_user(dev->phys, _IOC_SIZE(cmd), p);
562
563 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0)))
564 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p);
565
566 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
567
568 t = _IOC_NR(cmd) & ABS_MAX;
569
570 abs.value = dev->abs[t];
571 abs.minimum = dev->absmin[t];
572 abs.maximum = dev->absmax[t];
573 abs.fuzz = dev->absfuzz[t];
574 abs.flat = dev->absflat[t];
575
576 if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
577 return -EFAULT;
578
579 return 0;
580 }
581
582 }
583
584 if (_IOC_DIR(cmd) == _IOC_WRITE) {
585
586 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
587
588 t = _IOC_NR(cmd) & ABS_MAX;
589
590 if (copy_from_user(&abs, p, sizeof(struct input_absinfo)))
591 return -EFAULT;
592
593 dev->abs[t] = abs.value;
594 dev->absmin[t] = abs.minimum;
595 dev->absmax[t] = abs.maximum;
596 dev->absfuzz[t] = abs.fuzz;
597 dev->absflat[t] = abs.flat;
598
599 return 0;
600 }
601 }
602 }
603 return -EINVAL;
604}
605
606static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
607{
608 return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
609}
610
611#ifdef CONFIG_COMPAT
612static long evdev_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
613{
614 return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
615}
616#endif
617
618static const struct file_operations evdev_fops = {
619 .owner = THIS_MODULE,
620 .read = evdev_read,
621 .write = evdev_write,
622 .poll = evdev_poll,
623 .open = evdev_open,
624 .release = evdev_release,
625 .unlocked_ioctl = evdev_ioctl,
626#ifdef CONFIG_COMPAT
627 .compat_ioctl = evdev_ioctl_compat,
628#endif
629 .fasync = evdev_fasync,
630 .flush = evdev_flush
631};
632
633static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
634 const struct input_device_id *id)
635{
636 struct evdev *evdev;
637 int minor;
638 int error;
639
640 for (minor = 0; minor < EVDEV_MINORS && evdev_table[minor]; minor++);
641 if (minor == EVDEV_MINORS) {
642 printk(KERN_ERR "evdev: no more free evdev devices\n");
643 return -ENFILE;
644 }
645
646 evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
647 if (!evdev)
648 return -ENOMEM;
649
650 INIT_LIST_HEAD(&evdev->client_list);
651 init_waitqueue_head(&evdev->wait);
652
653 evdev->exist = 1;
654 evdev->minor = minor;
655 evdev->handle.dev = dev;
656 evdev->handle.name = evdev->name;
657 evdev->handle.handler = handler;
658 evdev->handle.private = evdev;
659 snprintf(evdev->name, sizeof(evdev->name), "event%d", minor);
660
661 snprintf(evdev->dev.bus_id, sizeof(evdev->dev.bus_id),
662 "event%d", minor);
663 evdev->dev.class = &input_class;
664 evdev->dev.parent = &dev->dev;
665 evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor);
666 evdev->dev.release = evdev_free;
667 device_initialize(&evdev->dev);
668
669 evdev_table[minor] = evdev;
670
671 error = device_add(&evdev->dev);
672 if (error)
673 goto err_free_evdev;
674
675 error = input_register_handle(&evdev->handle);
676 if (error)
677 goto err_delete_evdev;
678
679 return 0;
680
681 err_delete_evdev:
682 device_del(&evdev->dev);
683 err_free_evdev:
684 put_device(&evdev->dev);
685 return error;
686}
687
688static void evdev_disconnect(struct input_handle *handle)
689{
690 struct evdev *evdev = handle->private;
691 struct evdev_client *client;
692
693 input_unregister_handle(handle);
694 device_del(&evdev->dev);
695
696 evdev->exist = 0;
697
698 if (evdev->open) {
699 input_flush_device(handle, NULL);
700 input_close_device(handle);
701 list_for_each_entry(client, &evdev->client_list, node)
702 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
703 wake_up_interruptible(&evdev->wait);
704 }
705
706 put_device(&evdev->dev);
707}
708
709static const struct input_device_id evdev_ids[] = {
710 { .driver_info = 1 }, /* Matches all devices */
711 { }, /* Terminating zero entry */
712};
713
714MODULE_DEVICE_TABLE(input, evdev_ids);
715
716static struct input_handler evdev_handler = {
717 .event = evdev_event,
718 .connect = evdev_connect,
719 .disconnect = evdev_disconnect,
720 .fops = &evdev_fops,
721 .minor = EVDEV_MINOR_BASE,
722 .name = "evdev",
723 .id_table = evdev_ids,
724};
725
726static int __init evdev_init(void)
727{
728 return input_register_handler(&evdev_handler);
729}
730
731static void __exit evdev_exit(void)
732{
733 input_unregister_handler(&evdev_handler);
734}
735
736module_init(evdev_init);
737module_exit(evdev_exit);
738
739MODULE_AUTHOR("Vojtech Pavlik <[email protected]>");
740MODULE_DESCRIPTION("Input driver event char devices");
741MODULE_LICENSE("GPL");