Linux 2.6.28-rc9
[linux-2.6.git] / drivers / input / misc / uinput.c
1 /*
2  *  User level driver support for input subsystem
3  *
4  * Heavily based on evdev.c by Vojtech Pavlik
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19  *
20  * Author: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
21  *
22  * Changes/Revisions:
23  *      0.3     09/04/2006 (Anssi Hannula <anssi.hannula@gmail.com>)
24  *              - updated ff support for the changes in kernel interface
25  *              - added MODULE_VERSION
26  *      0.2     16/10/2004 (Micah Dowty <micah@navi.cx>)
27  *              - added force feedback support
28  *              - added UI_SET_PHYS
29  *      0.1     20/06/2002
30  *              - first public version
31  */
32 #include <linux/poll.h>
33 #include <linux/slab.h>
34 #include <linux/module.h>
35 #include <linux/init.h>
36 #include <linux/smp_lock.h>
37 #include <linux/fs.h>
38 #include <linux/miscdevice.h>
39 #include <linux/uinput.h>
40
41 static int uinput_dev_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
42 {
43         struct uinput_device    *udev = input_get_drvdata(dev);
44
45         udev->buff[udev->head].type = type;
46         udev->buff[udev->head].code = code;
47         udev->buff[udev->head].value = value;
48         do_gettimeofday(&udev->buff[udev->head].time);
49         udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
50
51         wake_up_interruptible(&udev->waitq);
52
53         return 0;
54 }
55
56 static int uinput_request_alloc_id(struct uinput_device *udev, struct uinput_request *request)
57 {
58         /* Atomically allocate an ID for the given request. Returns 0 on success. */
59         int id;
60         int err = -1;
61
62         spin_lock(&udev->requests_lock);
63
64         for (id = 0; id < UINPUT_NUM_REQUESTS; id++)
65                 if (!udev->requests[id]) {
66                         request->id = id;
67                         udev->requests[id] = request;
68                         err = 0;
69                         break;
70                 }
71
72         spin_unlock(&udev->requests_lock);
73         return err;
74 }
75
76 static struct uinput_request* uinput_request_find(struct uinput_device *udev, int id)
77 {
78         /* Find an input request, by ID. Returns NULL if the ID isn't valid. */
79         if (id >= UINPUT_NUM_REQUESTS || id < 0)
80                 return NULL;
81         return udev->requests[id];
82 }
83
84 static inline int uinput_request_reserve_slot(struct uinput_device *udev, struct uinput_request *request)
85 {
86         /* Allocate slot. If none are available right away, wait. */
87         return wait_event_interruptible(udev->requests_waitq,
88                                         !uinput_request_alloc_id(udev, request));
89 }
90
91 static void uinput_request_done(struct uinput_device *udev, struct uinput_request *request)
92 {
93         /* Mark slot as available */
94         udev->requests[request->id] = NULL;
95         wake_up(&udev->requests_waitq);
96
97         complete(&request->done);
98 }
99
100 static int uinput_request_submit(struct input_dev *dev, struct uinput_request *request)
101 {
102         /* Tell our userspace app about this new request by queueing an input event */
103         uinput_dev_event(dev, EV_UINPUT, request->code, request->id);
104
105         /* Wait for the request to complete */
106         wait_for_completion(&request->done);
107         return request->retval;
108 }
109
110 static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
111 {
112         uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
113 }
114
115 static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
116 {
117         uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
118 }
119
120 static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
121 {
122         return uinput_dev_event(dev, EV_FF, effect_id, value);
123 }
124
125 static int uinput_dev_upload_effect(struct input_dev *dev, struct ff_effect *effect, struct ff_effect *old)
126 {
127         struct uinput_request request;
128         int retval;
129
130         request.id = -1;
131         init_completion(&request.done);
132         request.code = UI_FF_UPLOAD;
133         request.u.upload.effect = effect;
134         request.u.upload.old = old;
135
136         retval = uinput_request_reserve_slot(input_get_drvdata(dev), &request);
137         if (!retval)
138                 retval = uinput_request_submit(dev, &request);
139
140         return retval;
141 }
142
143 static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
144 {
145         struct uinput_request request;
146         int retval;
147
148         if (!test_bit(EV_FF, dev->evbit))
149                 return -ENOSYS;
150
151         request.id = -1;
152         init_completion(&request.done);
153         request.code = UI_FF_ERASE;
154         request.u.effect_id = effect_id;
155
156         retval = uinput_request_reserve_slot(input_get_drvdata(dev), &request);
157         if (!retval)
158                 retval = uinput_request_submit(dev, &request);
159
160         return retval;
161 }
162
163 static void uinput_destroy_device(struct uinput_device *udev)
164 {
165         const char *name, *phys;
166
167         if (udev->dev) {
168                 name = udev->dev->name;
169                 phys = udev->dev->phys;
170                 if (udev->state == UIST_CREATED)
171                         input_unregister_device(udev->dev);
172                 else
173                         input_free_device(udev->dev);
174                 kfree(name);
175                 kfree(phys);
176                 udev->dev = NULL;
177         }
178
179         udev->state = UIST_NEW_DEVICE;
180 }
181
182 static int uinput_create_device(struct uinput_device *udev)
183 {
184         struct input_dev *dev = udev->dev;
185         int error;
186
187         if (udev->state != UIST_SETUP_COMPLETE) {
188                 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
189                 return -EINVAL;
190         }
191
192         if (udev->ff_effects_max) {
193                 error = input_ff_create(dev, udev->ff_effects_max);
194                 if (error)
195                         goto fail1;
196
197                 dev->ff->upload = uinput_dev_upload_effect;
198                 dev->ff->erase = uinput_dev_erase_effect;
199                 dev->ff->playback = uinput_dev_playback;
200                 dev->ff->set_gain = uinput_dev_set_gain;
201                 dev->ff->set_autocenter = uinput_dev_set_autocenter;
202         }
203
204         error = input_register_device(udev->dev);
205         if (error)
206                 goto fail2;
207
208         udev->state = UIST_CREATED;
209
210         return 0;
211
212  fail2: input_ff_destroy(dev);
213  fail1: uinput_destroy_device(udev);
214         return error;
215 }
216
217 static int uinput_open(struct inode *inode, struct file *file)
218 {
219         struct uinput_device *newdev;
220
221         newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
222         if (!newdev)
223                 return -ENOMEM;
224
225         lock_kernel();
226         mutex_init(&newdev->mutex);
227         spin_lock_init(&newdev->requests_lock);
228         init_waitqueue_head(&newdev->requests_waitq);
229         init_waitqueue_head(&newdev->waitq);
230         newdev->state = UIST_NEW_DEVICE;
231
232         file->private_data = newdev;
233         unlock_kernel();
234
235         return 0;
236 }
237
238 static int uinput_validate_absbits(struct input_dev *dev)
239 {
240         unsigned int cnt;
241         int retval = 0;
242
243         for (cnt = 0; cnt < ABS_MAX + 1; cnt++) {
244                 if (!test_bit(cnt, dev->absbit))
245                         continue;
246
247                 if ((dev->absmax[cnt] <= dev->absmin[cnt])) {
248                         printk(KERN_DEBUG
249                                 "%s: invalid abs[%02x] min:%d max:%d\n",
250                                 UINPUT_NAME, cnt,
251                                 dev->absmin[cnt], dev->absmax[cnt]);
252                         retval = -EINVAL;
253                         break;
254                 }
255
256                 if (dev->absflat[cnt] > (dev->absmax[cnt] - dev->absmin[cnt])) {
257                         printk(KERN_DEBUG
258                                 "%s: absflat[%02x] out of range: %d "
259                                 "(min:%d/max:%d)\n",
260                                 UINPUT_NAME, cnt, dev->absflat[cnt],
261                                 dev->absmin[cnt], dev->absmax[cnt]);
262                         retval = -EINVAL;
263                         break;
264                 }
265         }
266         return retval;
267 }
268
269 static int uinput_allocate_device(struct uinput_device *udev)
270 {
271         udev->dev = input_allocate_device();
272         if (!udev->dev)
273                 return -ENOMEM;
274
275         udev->dev->event = uinput_dev_event;
276         input_set_drvdata(udev->dev, udev);
277
278         return 0;
279 }
280
281 static int uinput_setup_device(struct uinput_device *udev, const char __user *buffer, size_t count)
282 {
283         struct uinput_user_dev  *user_dev;
284         struct input_dev        *dev;
285         char                    *name;
286         int                     size;
287         int                     retval;
288
289         if (count != sizeof(struct uinput_user_dev))
290                 return -EINVAL;
291
292         if (!udev->dev) {
293                 retval = uinput_allocate_device(udev);
294                 if (retval)
295                         return retval;
296         }
297
298         dev = udev->dev;
299
300         user_dev = kmalloc(sizeof(struct uinput_user_dev), GFP_KERNEL);
301         if (!user_dev)
302                 return -ENOMEM;
303
304         if (copy_from_user(user_dev, buffer, sizeof(struct uinput_user_dev))) {
305                 retval = -EFAULT;
306                 goto exit;
307         }
308
309         udev->ff_effects_max = user_dev->ff_effects_max;
310
311         size = strnlen(user_dev->name, UINPUT_MAX_NAME_SIZE) + 1;
312         if (!size) {
313                 retval = -EINVAL;
314                 goto exit;
315         }
316
317         kfree(dev->name);
318         dev->name = name = kmalloc(size, GFP_KERNEL);
319         if (!name) {
320                 retval = -ENOMEM;
321                 goto exit;
322         }
323         strlcpy(name, user_dev->name, size);
324
325         dev->id.bustype = user_dev->id.bustype;
326         dev->id.vendor  = user_dev->id.vendor;
327         dev->id.product = user_dev->id.product;
328         dev->id.version = user_dev->id.version;
329
330         size = sizeof(int) * (ABS_MAX + 1);
331         memcpy(dev->absmax, user_dev->absmax, size);
332         memcpy(dev->absmin, user_dev->absmin, size);
333         memcpy(dev->absfuzz, user_dev->absfuzz, size);
334         memcpy(dev->absflat, user_dev->absflat, size);
335
336         /* check if absmin/absmax/absfuzz/absflat are filled as
337          * told in Documentation/input/input-programming.txt */
338         if (test_bit(EV_ABS, dev->evbit)) {
339                 retval = uinput_validate_absbits(dev);
340                 if (retval < 0)
341                         goto exit;
342         }
343
344         udev->state = UIST_SETUP_COMPLETE;
345         retval = count;
346
347  exit:
348         kfree(user_dev);
349         return retval;
350 }
351
352 static inline ssize_t uinput_inject_event(struct uinput_device *udev, const char __user *buffer, size_t count)
353 {
354         struct input_event ev;
355
356         if (count != sizeof(struct input_event))
357                 return -EINVAL;
358
359         if (copy_from_user(&ev, buffer, sizeof(struct input_event)))
360                 return -EFAULT;
361
362         input_event(udev->dev, ev.type, ev.code, ev.value);
363
364         return sizeof(struct input_event);
365 }
366
367 static ssize_t uinput_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
368 {
369         struct uinput_device *udev = file->private_data;
370         int retval;
371
372         retval = mutex_lock_interruptible(&udev->mutex);
373         if (retval)
374                 return retval;
375
376         retval = udev->state == UIST_CREATED ?
377                         uinput_inject_event(udev, buffer, count) :
378                         uinput_setup_device(udev, buffer, count);
379
380         mutex_unlock(&udev->mutex);
381
382         return retval;
383 }
384
385 static ssize_t uinput_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
386 {
387         struct uinput_device *udev = file->private_data;
388         int retval = 0;
389
390         if (udev->state != UIST_CREATED)
391                 return -ENODEV;
392
393         if (udev->head == udev->tail && (file->f_flags & O_NONBLOCK))
394                 return -EAGAIN;
395
396         retval = wait_event_interruptible(udev->waitq,
397                         udev->head != udev->tail || udev->state != UIST_CREATED);
398         if (retval)
399                 return retval;
400
401         retval = mutex_lock_interruptible(&udev->mutex);
402         if (retval)
403                 return retval;
404
405         if (udev->state != UIST_CREATED) {
406                 retval = -ENODEV;
407                 goto out;
408         }
409
410         while (udev->head != udev->tail && retval + sizeof(struct input_event) <= count) {
411                 if (copy_to_user(buffer + retval, &udev->buff[udev->tail], sizeof(struct input_event))) {
412                         retval = -EFAULT;
413                         goto out;
414                 }
415                 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
416                 retval += sizeof(struct input_event);
417         }
418
419  out:
420         mutex_unlock(&udev->mutex);
421
422         return retval;
423 }
424
425 static unsigned int uinput_poll(struct file *file, poll_table *wait)
426 {
427         struct uinput_device *udev = file->private_data;
428
429         poll_wait(file, &udev->waitq, wait);
430
431         if (udev->head != udev->tail)
432                 return POLLIN | POLLRDNORM;
433
434         return 0;
435 }
436
437 static int uinput_release(struct inode *inode, struct file *file)
438 {
439         struct uinput_device *udev = file->private_data;
440
441         uinput_destroy_device(udev);
442         kfree(udev);
443
444         return 0;
445 }
446
447 #define uinput_set_bit(_arg, _bit, _max)                \
448 ({                                                      \
449         int __ret = 0;                                  \
450         if (udev->state == UIST_CREATED)                \
451                 __ret =  -EINVAL;                       \
452         else if ((_arg) > (_max))                       \
453                 __ret = -EINVAL;                        \
454         else set_bit((_arg), udev->dev->_bit);          \
455         __ret;                                          \
456 })
457
458 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
459 {
460         int                     retval;
461         struct uinput_device    *udev;
462         void __user             *p = (void __user *)arg;
463         struct uinput_ff_upload ff_up;
464         struct uinput_ff_erase  ff_erase;
465         struct uinput_request   *req;
466         int                     length;
467         char                    *phys;
468
469         udev = file->private_data;
470
471         retval = mutex_lock_interruptible(&udev->mutex);
472         if (retval)
473                 return retval;
474
475         if (!udev->dev) {
476                 retval = uinput_allocate_device(udev);
477                 if (retval)
478                         goto out;
479         }
480
481         switch (cmd) {
482                 case UI_DEV_CREATE:
483                         retval = uinput_create_device(udev);
484                         break;
485
486                 case UI_DEV_DESTROY:
487                         uinput_destroy_device(udev);
488                         break;
489
490                 case UI_SET_EVBIT:
491                         retval = uinput_set_bit(arg, evbit, EV_MAX);
492                         break;
493
494                 case UI_SET_KEYBIT:
495                         retval = uinput_set_bit(arg, keybit, KEY_MAX);
496                         break;
497
498                 case UI_SET_RELBIT:
499                         retval = uinput_set_bit(arg, relbit, REL_MAX);
500                         break;
501
502                 case UI_SET_ABSBIT:
503                         retval = uinput_set_bit(arg, absbit, ABS_MAX);
504                         break;
505
506                 case UI_SET_MSCBIT:
507                         retval = uinput_set_bit(arg, mscbit, MSC_MAX);
508                         break;
509
510                 case UI_SET_LEDBIT:
511                         retval = uinput_set_bit(arg, ledbit, LED_MAX);
512                         break;
513
514                 case UI_SET_SNDBIT:
515                         retval = uinput_set_bit(arg, sndbit, SND_MAX);
516                         break;
517
518                 case UI_SET_FFBIT:
519                         retval = uinput_set_bit(arg, ffbit, FF_MAX);
520                         break;
521
522                 case UI_SET_SWBIT:
523                         retval = uinput_set_bit(arg, swbit, SW_MAX);
524                         break;
525
526                 case UI_SET_PHYS:
527                         if (udev->state == UIST_CREATED) {
528                                 retval = -EINVAL;
529                                 goto out;
530                         }
531                         length = strnlen_user(p, 1024);
532                         if (length <= 0) {
533                                 retval = -EFAULT;
534                                 break;
535                         }
536                         kfree(udev->dev->phys);
537                         udev->dev->phys = phys = kmalloc(length, GFP_KERNEL);
538                         if (!phys) {
539                                 retval = -ENOMEM;
540                                 break;
541                         }
542                         if (copy_from_user(phys, p, length)) {
543                                 udev->dev->phys = NULL;
544                                 kfree(phys);
545                                 retval = -EFAULT;
546                                 break;
547                         }
548                         phys[length - 1] = '\0';
549                         break;
550
551                 case UI_BEGIN_FF_UPLOAD:
552                         if (copy_from_user(&ff_up, p, sizeof(ff_up))) {
553                                 retval = -EFAULT;
554                                 break;
555                         }
556                         req = uinput_request_find(udev, ff_up.request_id);
557                         if (!(req && req->code == UI_FF_UPLOAD && req->u.upload.effect)) {
558                                 retval = -EINVAL;
559                                 break;
560                         }
561                         ff_up.retval = 0;
562                         memcpy(&ff_up.effect, req->u.upload.effect, sizeof(struct ff_effect));
563                         if (req->u.upload.old)
564                                 memcpy(&ff_up.old, req->u.upload.old, sizeof(struct ff_effect));
565                         else
566                                 memset(&ff_up.old, 0, sizeof(struct ff_effect));
567
568                         if (copy_to_user(p, &ff_up, sizeof(ff_up))) {
569                                 retval = -EFAULT;
570                                 break;
571                         }
572                         break;
573
574                 case UI_BEGIN_FF_ERASE:
575                         if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
576                                 retval = -EFAULT;
577                                 break;
578                         }
579                         req = uinput_request_find(udev, ff_erase.request_id);
580                         if (!(req && req->code == UI_FF_ERASE)) {
581                                 retval = -EINVAL;
582                                 break;
583                         }
584                         ff_erase.retval = 0;
585                         ff_erase.effect_id = req->u.effect_id;
586                         if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
587                                 retval = -EFAULT;
588                                 break;
589                         }
590                         break;
591
592                 case UI_END_FF_UPLOAD:
593                         if (copy_from_user(&ff_up, p, sizeof(ff_up))) {
594                                 retval = -EFAULT;
595                                 break;
596                         }
597                         req = uinput_request_find(udev, ff_up.request_id);
598                         if (!(req && req->code == UI_FF_UPLOAD && req->u.upload.effect)) {
599                                 retval = -EINVAL;
600                                 break;
601                         }
602                         req->retval = ff_up.retval;
603                         uinput_request_done(udev, req);
604                         break;
605
606                 case UI_END_FF_ERASE:
607                         if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
608                                 retval = -EFAULT;
609                                 break;
610                         }
611                         req = uinput_request_find(udev, ff_erase.request_id);
612                         if (!(req && req->code == UI_FF_ERASE)) {
613                                 retval = -EINVAL;
614                                 break;
615                         }
616                         req->retval = ff_erase.retval;
617                         uinput_request_done(udev, req);
618                         break;
619
620                 default:
621                         retval = -EINVAL;
622         }
623
624  out:
625         mutex_unlock(&udev->mutex);
626         return retval;
627 }
628
629 static const struct file_operations uinput_fops = {
630         .owner          = THIS_MODULE,
631         .open           = uinput_open,
632         .release        = uinput_release,
633         .read           = uinput_read,
634         .write          = uinput_write,
635         .poll           = uinput_poll,
636         .unlocked_ioctl = uinput_ioctl,
637 };
638
639 static struct miscdevice uinput_misc = {
640         .fops           = &uinput_fops,
641         .minor          = UINPUT_MINOR,
642         .name           = UINPUT_NAME,
643 };
644
645 static int __init uinput_init(void)
646 {
647         return misc_register(&uinput_misc);
648 }
649
650 static void __exit uinput_exit(void)
651 {
652         misc_deregister(&uinput_misc);
653 }
654
655 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
656 MODULE_DESCRIPTION("User level driver support for input subsystem");
657 MODULE_LICENSE("GPL");
658 MODULE_VERSION("0.3");
659
660 module_init(uinput_init);
661 module_exit(uinput_exit);
662