projects/linux·blob v2.6.22 · refs

741 lines · 17.3 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};
34
35struct evdev_client {
36 struct input_event buffer[EVDEV_BUFFER_SIZE];
37 int head;
38 int tail;
39 struct fasync_struct *fasync;
40 struct evdev *evdev;
41 struct list_head node;
42};
43
44static struct evdev *evdev_table[EVDEV_MINORS];
45
46static void evdev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
47{
48 struct evdev *evdev = handle->private;
49 struct evdev_client *client;
50
51 if (evdev->grab) {
52 client = evdev->grab;
53
54 do_gettimeofday(&client->buffer[client->head].time);
55 client->buffer[client->head].type = type;
56 client->buffer[client->head].code = code;
57 client->buffer[client->head].value = value;
58 client->head = (client->head + 1) & (EVDEV_BUFFER_SIZE - 1);
59
60 kill_fasync(&client->fasync, SIGIO, POLL_IN);
61 } else
62 list_for_each_entry(client, &evdev->client_list, node) {
63
64 do_gettimeofday(&client->buffer[client->head].time);
65 client->buffer[client->head].type = type;
66 client->buffer[client->head].code = code;
67 client->buffer[client->head].value = value;
68 client->head = (client->head + 1) & (EVDEV_BUFFER_SIZE - 1);
69
70 kill_fasync(&client->fasync, SIGIO, POLL_IN);
71 }
72
73 wake_up_interruptible(&evdev->wait);
74}
75
76static int evdev_fasync(int fd, struct file *file, int on)
77{
78 struct evdev_client *client = file->private_data;
79 int retval;
80
81 retval = fasync_helper(fd, file, on, &client->fasync);
82
83 return retval < 0 ? retval : 0;
84}
85
86static int evdev_flush(struct file *file, fl_owner_t id)
87{
88 struct evdev_client *client = file->private_data;
89 struct evdev *evdev = client->evdev;
90
91 if (!evdev->exist)
92 return -ENODEV;
93
94 return input_flush_device(&evdev->handle, file);
95}
96
97static void evdev_free(struct evdev *evdev)
98{
99 evdev_table[evdev->minor] = NULL;
100 kfree(evdev);
101}
102
103static int evdev_release(struct inode *inode, struct file *file)
104{
105 struct evdev_client *client = file->private_data;
106 struct evdev *evdev = client->evdev;
107
108 if (evdev->grab == client) {
109 input_release_device(&evdev->handle);
110 evdev->grab = NULL;
111 }
112
113 evdev_fasync(-1, file, 0);
114 list_del(&client->node);
115 kfree(client);
116
117 if (!--evdev->open) {
118 if (evdev->exist)
119 input_close_device(&evdev->handle);
120 else
121 evdev_free(evdev);
122 }
123
124 return 0;
125}
126
127static int evdev_open(struct inode *inode, struct file *file)
128{
129 struct evdev_client *client;
130 struct evdev *evdev;
131 int i = iminor(inode) - EVDEV_MINOR_BASE;
132 int error;
133
134 if (i >= EVDEV_MINORS)
135 return -ENODEV;
136
137 evdev = evdev_table[i];
138
139 if (!evdev || !evdev->exist)
140 return -ENODEV;
141
142 client = kzalloc(sizeof(struct evdev_client), GFP_KERNEL);
143 if (!client)
144 return -ENOMEM;
145
146 client->evdev = evdev;
147 list_add_tail(&client->node, &evdev->client_list);
148
149 if (!evdev->open++ && evdev->exist) {
150 error = input_open_device(&evdev->handle);
151 if (error) {
152 list_del(&client->node);
153 kfree(client);
154 return error;
155 }
156 }
157
158 file->private_data = client;
159 return 0;
160}
161
162#ifdef CONFIG_COMPAT
163
164struct input_event_compat {
165 struct compat_timeval time;
166 __u16 type;
167 __u16 code;
168 __s32 value;
169};
170
171/* Note to the author of this code: did it ever occur to
172 you why the ifdefs are needed? Think about it again. -AK */
173#ifdef CONFIG_X86_64
174# define COMPAT_TEST is_compat_task()
175#elif defined(CONFIG_IA64)
176# define COMPAT_TEST IS_IA32_PROCESS(task_pt_regs(current))
177#elif defined(CONFIG_S390)
178# define COMPAT_TEST test_thread_flag(TIF_31BIT)
179#elif defined(CONFIG_MIPS)
180# define COMPAT_TEST (current->thread.mflags & MF_32BIT_ADDR)
181#else
182# define COMPAT_TEST test_thread_flag(TIF_32BIT)
183#endif
184
185static inline size_t evdev_event_size(void)
186{
187 return COMPAT_TEST ?
188 sizeof(struct input_event_compat) : sizeof(struct input_event);
189}
190
191static int evdev_event_from_user(const char __user *buffer, struct input_event *event)
192{
193 if (COMPAT_TEST) {
194 struct input_event_compat compat_event;
195
196 if (copy_from_user(&compat_event, buffer, sizeof(struct input_event_compat)))
197 return -EFAULT;
198
199 event->time.tv_sec = compat_event.time.tv_sec;
200 event->time.tv_usec = compat_event.time.tv_usec;
201 event->type = compat_event.type;
202 event->code = compat_event.code;
203 event->value = compat_event.value;
204
205 } else {
206 if (copy_from_user(event, buffer, sizeof(struct input_event)))
207 return -EFAULT;
208 }
209
210 return 0;
211}
212
213static int evdev_event_to_user(char __user *buffer, const struct input_event *event)
214{
215 if (COMPAT_TEST) {
216 struct input_event_compat compat_event;
217
218 compat_event.time.tv_sec = event->time.tv_sec;
219 compat_event.time.tv_usec = event->time.tv_usec;
220 compat_event.type = event->type;
221 compat_event.code = event->code;
222 compat_event.value = event->value;
223
224 if (copy_to_user(buffer, &compat_event, sizeof(struct input_event_compat)))
225 return -EFAULT;
226
227 } else {
228 if (copy_to_user(buffer, event, sizeof(struct input_event)))
229 return -EFAULT;
230 }
231
232 return 0;
233}
234
235#else
236
237static inline size_t evdev_event_size(void)
238{
239 return sizeof(struct input_event);
240}
241
242static int evdev_event_from_user(const char __user *buffer, struct input_event *event)
243{
244 if (copy_from_user(event, buffer, sizeof(struct input_event)))
245 return -EFAULT;
246
247 return 0;
248}
249
250static int evdev_event_to_user(char __user *buffer, const struct input_event *event)
251{
252 if (copy_to_user(buffer, event, sizeof(struct input_event)))
253 return -EFAULT;
254
255 return 0;
256}
257
258#endif /* CONFIG_COMPAT */
259
260static ssize_t evdev_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
261{
262 struct evdev_client *client = file->private_data;
263 struct evdev *evdev = client->evdev;
264 struct input_event event;
265 int retval = 0;
266
267 if (!evdev->exist)
268 return -ENODEV;
269
270 while (retval < count) {
271
272 if (evdev_event_from_user(buffer + retval, &event))
273 return -EFAULT;
274 input_inject_event(&evdev->handle, event.type, event.code, event.value);
275 retval += evdev_event_size();
276 }
277
278 return retval;
279}
280
281static ssize_t evdev_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
282{
283 struct evdev_client *client = file->private_data;
284 struct evdev *evdev = client->evdev;
285 int retval;
286
287 if (count < evdev_event_size())
288 return -EINVAL;
289
290 if (client->head == client->tail && evdev->exist && (file->f_flags & O_NONBLOCK))
291 return -EAGAIN;
292
293 retval = wait_event_interruptible(evdev->wait,
294 client->head != client->tail || !evdev->exist);
295 if (retval)
296 return retval;
297
298 if (!evdev->exist)
299 return -ENODEV;
300
301 while (client->head != client->tail && retval + evdev_event_size() <= count) {
302
303 struct input_event *event = (struct input_event *) client->buffer + client->tail;
304
305 if (evdev_event_to_user(buffer + retval, event))
306 return -EFAULT;
307
308 client->tail = (client->tail + 1) & (EVDEV_BUFFER_SIZE - 1);
309 retval += evdev_event_size();
310 }
311
312 return retval;
313}
314
315/* No kernel lock - fine */
316static unsigned int evdev_poll(struct file *file, poll_table *wait)
317{
318 struct evdev_client *client = file->private_data;
319 struct evdev *evdev = client->evdev;
320
321 poll_wait(file, &evdev->wait, wait);
322 return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) |
323 (evdev->exist ? 0 : (POLLHUP | POLLERR));
324}
325
326#ifdef CONFIG_COMPAT
327
328#define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8)
329#define NBITS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1)
330
331#ifdef __BIG_ENDIAN
332static int bits_to_user(unsigned long *bits, unsigned int maxbit,
333 unsigned int maxlen, void __user *p, int compat)
334{
335 int len, i;
336
337 if (compat) {
338 len = NBITS_COMPAT(maxbit) * sizeof(compat_long_t);
339 if (len > maxlen)
340 len = maxlen;
341
342 for (i = 0; i < len / sizeof(compat_long_t); i++)
343 if (copy_to_user((compat_long_t __user *) p + i,
344 (compat_long_t *) bits +
345 i + 1 - ((i % 2) << 1),
346 sizeof(compat_long_t)))
347 return -EFAULT;
348 } else {
349 len = NBITS(maxbit) * sizeof(long);
350 if (len > maxlen)
351 len = maxlen;
352
353 if (copy_to_user(p, bits, len))
354 return -EFAULT;
355 }
356
357 return len;
358}
359#else
360static int bits_to_user(unsigned long *bits, unsigned int maxbit,
361 unsigned int maxlen, void __user *p, int compat)
362{
363 int len = compat ?
364 NBITS_COMPAT(maxbit) * sizeof(compat_long_t) :
365 NBITS(maxbit) * sizeof(long);
366
367 if (len > maxlen)
368 len = maxlen;
369
370 return copy_to_user(p, bits, len) ? -EFAULT : len;
371}
372#endif /* __BIG_ENDIAN */
373
374#else
375
376static int bits_to_user(unsigned long *bits, unsigned int maxbit,
377 unsigned int maxlen, void __user *p, int compat)
378{
379 int len = NBITS(maxbit) * sizeof(long);
380
381 if (len > maxlen)
382 len = maxlen;
383
384 return copy_to_user(p, bits, len) ? -EFAULT : len;
385}
386
387#endif /* CONFIG_COMPAT */
388
389static int str_to_user(const char *str, unsigned int maxlen, void __user *p)
390{
391 int len;
392
393 if (!str)
394 return -ENOENT;
395
396 len = strlen(str) + 1;
397 if (len > maxlen)
398 len = maxlen;
399
400 return copy_to_user(p, str, len) ? -EFAULT : len;
401}
402
403static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
404 void __user *p, int compat_mode)
405{
406 struct evdev_client *client = file->private_data;
407 struct evdev *evdev = client->evdev;
408 struct input_dev *dev = evdev->handle.dev;
409 struct input_absinfo abs;
410 struct ff_effect effect;
411 int __user *ip = (int __user *)p;
412 int i, t, u, v;
413 int error;
414
415 if (!evdev->exist)
416 return -ENODEV;
417
418 switch (cmd) {
419
420 case EVIOCGVERSION:
421 return put_user(EV_VERSION, ip);
422
423 case EVIOCGID:
424 if (copy_to_user(p, &dev->id, sizeof(struct input_id)))
425 return -EFAULT;
426 return 0;
427
428 case EVIOCGREP:
429 if (!test_bit(EV_REP, dev->evbit))
430 return -ENOSYS;
431 if (put_user(dev->rep[REP_DELAY], ip))
432 return -EFAULT;
433 if (put_user(dev->rep[REP_PERIOD], ip + 1))
434 return -EFAULT;
435 return 0;
436
437 case EVIOCSREP:
438 if (!test_bit(EV_REP, dev->evbit))
439 return -ENOSYS;
440 if (get_user(u, ip))
441 return -EFAULT;
442 if (get_user(v, ip + 1))
443 return -EFAULT;
444
445 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u);
446 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v);
447
448 return 0;
449
450 case EVIOCGKEYCODE:
451 if (get_user(t, ip))
452 return -EFAULT;
453
454 error = dev->getkeycode(dev, t, &v);
455 if (error)
456 return error;
457
458 if (put_user(v, ip + 1))
459 return -EFAULT;
460
461 return 0;
462
463 case EVIOCSKEYCODE:
464 if (get_user(t, ip) || get_user(v, ip + 1))
465 return -EFAULT;
466
467 return dev->setkeycode(dev, t, v);
468
469 case EVIOCSFF:
470 if (copy_from_user(&effect, p, sizeof(effect)))
471 return -EFAULT;
472
473 error = input_ff_upload(dev, &effect, file);
474
475 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
476 return -EFAULT;
477
478 return error;
479
480 case EVIOCRMFF:
481 return input_ff_erase(dev, (int)(unsigned long) p, file);
482
483 case EVIOCGEFFECTS:
484 i = test_bit(EV_FF, dev->evbit) ? dev->ff->max_effects : 0;
485 if (put_user(i, ip))
486 return -EFAULT;
487 return 0;
488
489 case EVIOCGRAB:
490 if (p) {
491 if (evdev->grab)
492 return -EBUSY;
493 if (input_grab_device(&evdev->handle))
494 return -EBUSY;
495 evdev->grab = client;
496 return 0;
497 } else {
498 if (evdev->grab != client)
499 return -EINVAL;
500 input_release_device(&evdev->handle);
501 evdev->grab = NULL;
502 return 0;
503 }
504
505 default:
506
507 if (_IOC_TYPE(cmd) != 'E')
508 return -EINVAL;
509
510 if (_IOC_DIR(cmd) == _IOC_READ) {
511
512 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) {
513
514 unsigned long *bits;
515 int len;
516
517 switch (_IOC_NR(cmd) & EV_MAX) {
518 case 0: bits = dev->evbit; len = EV_MAX; break;
519 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
520 case EV_REL: bits = dev->relbit; len = REL_MAX; break;
521 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
522 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break;
523 case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
524 case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
525 case EV_FF: bits = dev->ffbit; len = FF_MAX; break;
526 case EV_SW: bits = dev->swbit; len = SW_MAX; break;
527 default: return -EINVAL;
528 }
529 return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode);
530 }
531
532 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0)))
533 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd),
534 p, compat_mode);
535
536 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0)))
537 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd),
538 p, compat_mode);
539
540 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0)))
541 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd),
542 p, compat_mode);
543
544 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0)))
545 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd),
546 p, compat_mode);
547
548 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0)))
549 return str_to_user(dev->name, _IOC_SIZE(cmd), p);
550
551 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0)))
552 return str_to_user(dev->phys, _IOC_SIZE(cmd), p);
553
554 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0)))
555 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p);
556
557 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
558
559 t = _IOC_NR(cmd) & ABS_MAX;
560
561 abs.value = dev->abs[t];
562 abs.minimum = dev->absmin[t];
563 abs.maximum = dev->absmax[t];
564 abs.fuzz = dev->absfuzz[t];
565 abs.flat = dev->absflat[t];
566
567 if (copy_to_user(p, &abs, sizeof(struct input_absinfo)))
568 return -EFAULT;
569
570 return 0;
571 }
572
573 }
574
575 if (_IOC_DIR(cmd) == _IOC_WRITE) {
576
577 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) {
578
579 t = _IOC_NR(cmd) & ABS_MAX;
580
581 if (copy_from_user(&abs, p, sizeof(struct input_absinfo)))
582 return -EFAULT;
583
584 dev->abs[t] = abs.value;
585 dev->absmin[t] = abs.minimum;
586 dev->absmax[t] = abs.maximum;
587 dev->absfuzz[t] = abs.fuzz;
588 dev->absflat[t] = abs.flat;
589
590 return 0;
591 }
592 }
593 }
594 return -EINVAL;
595}
596
597static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
598{
599 return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
600}
601
602#ifdef CONFIG_COMPAT
603static long evdev_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
604{
605 return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
606}
607#endif
608
609static const struct file_operations evdev_fops = {
610 .owner = THIS_MODULE,
611 .read = evdev_read,
612 .write = evdev_write,
613 .poll = evdev_poll,
614 .open = evdev_open,
615 .release = evdev_release,
616 .unlocked_ioctl = evdev_ioctl,
617#ifdef CONFIG_COMPAT
618 .compat_ioctl = evdev_ioctl_compat,
619#endif
620 .fasync = evdev_fasync,
621 .flush = evdev_flush
622};
623
624static int evdev_connect(struct input_handler *handler, struct input_dev *dev,
625 const struct input_device_id *id)
626{
627 struct evdev *evdev;
628 struct class_device *cdev;
629 dev_t devt;
630 int minor;
631 int error;
632
633 for (minor = 0; minor < EVDEV_MINORS && evdev_table[minor]; minor++);
634 if (minor == EVDEV_MINORS) {
635 printk(KERN_ERR "evdev: no more free evdev devices\n");
636 return -ENFILE;
637 }
638
639 evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL);
640 if (!evdev)
641 return -ENOMEM;
642
643 INIT_LIST_HEAD(&evdev->client_list);
644 init_waitqueue_head(&evdev->wait);
645
646 evdev->exist = 1;
647 evdev->minor = minor;
648 evdev->handle.dev = dev;
649 evdev->handle.name = evdev->name;
650 evdev->handle.handler = handler;
651 evdev->handle.private = evdev;
652 sprintf(evdev->name, "event%d", minor);
653
654 evdev_table[minor] = evdev;
655
656 devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor),
657
658 cdev = class_device_create(&input_class, &dev->cdev, devt,
659 dev->cdev.dev, evdev->name);
660 if (IS_ERR(cdev)) {
661 error = PTR_ERR(cdev);
662 goto err_free_evdev;
663 }
664
665 /* temporary symlink to keep userspace happy */
666 error = sysfs_create_link(&input_class.subsys.kobj,
667 &cdev->kobj, evdev->name);
668 if (error)
669 goto err_cdev_destroy;
670
671 error = input_register_handle(&evdev->handle);
672 if (error)
673 goto err_remove_link;
674
675 return 0;
676
677 err_remove_link:
678 sysfs_remove_link(&input_class.subsys.kobj, evdev->name);
679 err_cdev_destroy:
680 class_device_destroy(&input_class, devt);
681 err_free_evdev:
682 kfree(evdev);
683 evdev_table[minor] = NULL;
684 return error;
685}
686
687static void evdev_disconnect(struct input_handle *handle)
688{
689 struct evdev *evdev = handle->private;
690 struct evdev_client *client;
691
692 input_unregister_handle(handle);
693
694 sysfs_remove_link(&input_class.subsys.kobj, evdev->name);
695 class_device_destroy(&input_class,
696 MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + evdev->minor));
697 evdev->exist = 0;
698
699 if (evdev->open) {
700 input_flush_device(handle, NULL);
701 input_close_device(handle);
702 list_for_each_entry(client, &evdev->client_list, node)
703 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
704 wake_up_interruptible(&evdev->wait);
705 } else
706 evdev_free(evdev);
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");