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[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  *      0.2     16/10/2004 (Micah Dowty <micah@navi.cx>)
24  *              - added force feedback support
25  *              - added UI_SET_PHYS
26  *      0.1     20/06/2002
27  *              - first public version
28  */
29 #include <linux/poll.h>
30 #include <linux/slab.h>
31 #include <linux/module.h>
32 #include <linux/init.h>
33 #include <linux/input.h>
34 #include <linux/smp_lock.h>
35 #include <linux/fs.h>
36 #include <linux/miscdevice.h>
37 #include <linux/uinput.h>
38
39 static int uinput_dev_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
40 {
41         struct uinput_device    *udev;
42
43         udev = dev->private;
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 int uinput_dev_upload_effect(struct input_dev *dev, struct ff_effect *effect)
111 {
112         struct uinput_request request;
113         int retval;
114
115         if (!test_bit(EV_FF, dev->evbit))
116                 return -ENOSYS;
117
118         request.id = -1;
119         init_completion(&request.done);
120         request.code = UI_FF_UPLOAD;
121         request.u.effect = effect;
122
123         retval = uinput_request_reserve_slot(dev->private, &request);
124         if (!retval)
125                 retval = uinput_request_submit(dev, &request);
126
127         return retval;
128 }
129
130 static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
131 {
132         struct uinput_request request;
133         int retval;
134
135         if (!test_bit(EV_FF, dev->evbit))
136                 return -ENOSYS;
137
138         request.id = -1;
139         init_completion(&request.done);
140         request.code = UI_FF_ERASE;
141         request.u.effect_id = effect_id;
142
143         retval = uinput_request_reserve_slot(dev->private, &request);
144         if (!retval)
145                 retval = uinput_request_submit(dev, &request);
146
147         return retval;
148 }
149
150 static void uinput_destroy_device(struct uinput_device *udev)
151 {
152         const char *name, *phys;
153
154         if (udev->dev) {
155                 name = udev->dev->name;
156                 phys = udev->dev->phys;
157                 if (udev->state == UIST_CREATED)
158                         input_unregister_device(udev->dev);
159                 else
160                         input_free_device(udev->dev);
161                 kfree(name);
162                 kfree(phys);
163                 udev->dev = NULL;
164         }
165
166         udev->state = UIST_NEW_DEVICE;
167 }
168
169 static int uinput_create_device(struct uinput_device *udev)
170 {
171         int error;
172
173         if (udev->state != UIST_SETUP_COMPLETE) {
174                 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
175                 return -EINVAL;
176         }
177
178         error = input_register_device(udev->dev);
179         if (error) {
180                 uinput_destroy_device(udev);
181                 return error;
182         }
183
184         udev->state = UIST_CREATED;
185
186         return 0;
187 }
188
189 static int uinput_open(struct inode *inode, struct file *file)
190 {
191         struct uinput_device *newdev;
192
193         newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
194         if (!newdev)
195                 return -ENOMEM;
196
197         mutex_init(&newdev->mutex);
198         spin_lock_init(&newdev->requests_lock);
199         init_waitqueue_head(&newdev->requests_waitq);
200         init_waitqueue_head(&newdev->waitq);
201         newdev->state = UIST_NEW_DEVICE;
202
203         file->private_data = newdev;
204
205         return 0;
206 }
207
208 static int uinput_validate_absbits(struct input_dev *dev)
209 {
210         unsigned int cnt;
211         int retval = 0;
212
213         for (cnt = 0; cnt < ABS_MAX + 1; cnt++) {
214                 if (!test_bit(cnt, dev->absbit))
215                         continue;
216
217                 if ((dev->absmax[cnt] <= dev->absmin[cnt])) {
218                         printk(KERN_DEBUG
219                                 "%s: invalid abs[%02x] min:%d max:%d\n",
220                                 UINPUT_NAME, cnt,
221                                 dev->absmin[cnt], dev->absmax[cnt]);
222                         retval = -EINVAL;
223                         break;
224                 }
225
226                 if (dev->absflat[cnt] > (dev->absmax[cnt] - dev->absmin[cnt])) {
227                         printk(KERN_DEBUG
228                                 "%s: absflat[%02x] out of range: %d "
229                                 "(min:%d/max:%d)\n",
230                                 UINPUT_NAME, cnt, dev->absflat[cnt],
231                                 dev->absmin[cnt], dev->absmax[cnt]);
232                         retval = -EINVAL;
233                         break;
234                 }
235         }
236         return retval;
237 }
238
239 static int uinput_allocate_device(struct uinput_device *udev)
240 {
241         udev->dev = input_allocate_device();
242         if (!udev->dev)
243                 return -ENOMEM;
244
245         udev->dev->event = uinput_dev_event;
246         udev->dev->upload_effect = uinput_dev_upload_effect;
247         udev->dev->erase_effect = uinput_dev_erase_effect;
248         udev->dev->private = udev;
249
250         return 0;
251 }
252
253 static int uinput_setup_device(struct uinput_device *udev, const char __user *buffer, size_t count)
254 {
255         struct uinput_user_dev  *user_dev;
256         struct input_dev        *dev;
257         char                    *name;
258         int                     size;
259         int                     retval;
260
261         if (count != sizeof(struct uinput_user_dev))
262                 return -EINVAL;
263
264         if (!udev->dev) {
265                 retval = uinput_allocate_device(udev);
266                 if (retval)
267                         return retval;
268         }
269
270         dev = udev->dev;
271
272         user_dev = kmalloc(sizeof(struct uinput_user_dev), GFP_KERNEL);
273         if (!user_dev)
274                 return -ENOMEM;
275
276         if (copy_from_user(user_dev, buffer, sizeof(struct uinput_user_dev))) {
277                 retval = -EFAULT;
278                 goto exit;
279         }
280
281         size = strnlen(user_dev->name, UINPUT_MAX_NAME_SIZE) + 1;
282         if (!size) {
283                 retval = -EINVAL;
284                 goto exit;
285         }
286
287         kfree(dev->name);
288         dev->name = name = kmalloc(size, GFP_KERNEL);
289         if (!name) {
290                 retval = -ENOMEM;
291                 goto exit;
292         }
293         strlcpy(name, user_dev->name, size);
294
295         dev->id.bustype = user_dev->id.bustype;
296         dev->id.vendor  = user_dev->id.vendor;
297         dev->id.product = user_dev->id.product;
298         dev->id.version = user_dev->id.version;
299         dev->ff_effects_max = user_dev->ff_effects_max;
300
301         size = sizeof(int) * (ABS_MAX + 1);
302         memcpy(dev->absmax, user_dev->absmax, size);
303         memcpy(dev->absmin, user_dev->absmin, size);
304         memcpy(dev->absfuzz, user_dev->absfuzz, size);
305         memcpy(dev->absflat, user_dev->absflat, size);
306
307         /* check if absmin/absmax/absfuzz/absflat are filled as
308          * told in Documentation/input/input-programming.txt */
309         if (test_bit(EV_ABS, dev->evbit)) {
310                 retval = uinput_validate_absbits(dev);
311                 if (retval < 0)
312                         goto exit;
313         }
314
315         udev->state = UIST_SETUP_COMPLETE;
316         retval = count;
317
318  exit:
319         kfree(user_dev);
320         return retval;
321 }
322
323 static inline ssize_t uinput_inject_event(struct uinput_device *udev, const char __user *buffer, size_t count)
324 {
325         struct input_event ev;
326
327         if (count != sizeof(struct input_event))
328                 return -EINVAL;
329
330         if (copy_from_user(&ev, buffer, sizeof(struct input_event)))
331                 return -EFAULT;
332
333         input_event(udev->dev, ev.type, ev.code, ev.value);
334
335         return sizeof(struct input_event);
336 }
337
338 static ssize_t uinput_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
339 {
340         struct uinput_device *udev = file->private_data;
341         int retval;
342
343         retval = mutex_lock_interruptible(&udev->mutex);
344         if (retval)
345                 return retval;
346
347         retval = udev->state == UIST_CREATED ?
348                         uinput_inject_event(udev, buffer, count) :
349                         uinput_setup_device(udev, buffer, count);
350
351         mutex_unlock(&udev->mutex);
352
353         return retval;
354 }
355
356 static ssize_t uinput_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
357 {
358         struct uinput_device *udev = file->private_data;
359         int retval = 0;
360
361         if (udev->state != UIST_CREATED)
362                 return -ENODEV;
363
364         if (udev->head == udev->tail && (file->f_flags & O_NONBLOCK))
365                 return -EAGAIN;
366
367         retval = wait_event_interruptible(udev->waitq,
368                         udev->head != udev->tail || udev->state != UIST_CREATED);
369         if (retval)
370                 return retval;
371
372         retval = mutex_lock_interruptible(&udev->mutex);
373         if (retval)
374                 return retval;
375
376         if (udev->state != UIST_CREATED) {
377                 retval = -ENODEV;
378                 goto out;
379         }
380
381         while (udev->head != udev->tail && retval + sizeof(struct input_event) <= count) {
382                 if (copy_to_user(buffer + retval, &udev->buff[udev->tail], sizeof(struct input_event))) {
383                         retval = -EFAULT;
384                         goto out;
385                 }
386                 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
387                 retval += sizeof(struct input_event);
388         }
389
390  out:
391         mutex_unlock(&udev->mutex);
392
393         return retval;
394 }
395
396 static unsigned int uinput_poll(struct file *file, poll_table *wait)
397 {
398         struct uinput_device *udev = file->private_data;
399
400         poll_wait(file, &udev->waitq, wait);
401
402         if (udev->head != udev->tail)
403                 return POLLIN | POLLRDNORM;
404
405         return 0;
406 }
407
408 static int uinput_release(struct inode *inode, struct file *file)
409 {
410         struct uinput_device *udev = file->private_data;
411
412         uinput_destroy_device(udev);
413         kfree(udev);
414
415         return 0;
416 }
417
418 #define uinput_set_bit(_arg, _bit, _max)                \
419 ({                                                      \
420         int __ret = 0;                                  \
421         if (udev->state == UIST_CREATED)                \
422                 __ret =  -EINVAL;                       \
423         else if ((_arg) > (_max))                       \
424                 __ret = -EINVAL;                        \
425         else set_bit((_arg), udev->dev->_bit);          \
426         __ret;                                          \
427 })
428
429 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
430 {
431         int                     retval;
432         struct uinput_device    *udev;
433         void __user             *p = (void __user *)arg;
434         struct uinput_ff_upload ff_up;
435         struct uinput_ff_erase  ff_erase;
436         struct uinput_request   *req;
437         int                     length;
438         char                    *phys;
439
440         udev = file->private_data;
441
442         retval = mutex_lock_interruptible(&udev->mutex);
443         if (retval)
444                 return retval;
445
446         if (!udev->dev) {
447                 retval = uinput_allocate_device(udev);
448                 if (retval)
449                         goto out;
450         }
451
452         switch (cmd) {
453                 case UI_DEV_CREATE:
454                         retval = uinput_create_device(udev);
455                         break;
456
457                 case UI_DEV_DESTROY:
458                         uinput_destroy_device(udev);
459                         break;
460
461                 case UI_SET_EVBIT:
462                         retval = uinput_set_bit(arg, evbit, EV_MAX);
463                         break;
464
465                 case UI_SET_KEYBIT:
466                         retval = uinput_set_bit(arg, keybit, KEY_MAX);
467                         break;
468
469                 case UI_SET_RELBIT:
470                         retval = uinput_set_bit(arg, relbit, REL_MAX);
471                         break;
472
473                 case UI_SET_ABSBIT:
474                         retval = uinput_set_bit(arg, absbit, ABS_MAX);
475                         break;
476
477                 case UI_SET_MSCBIT:
478                         retval = uinput_set_bit(arg, mscbit, MSC_MAX);
479                         break;
480
481                 case UI_SET_LEDBIT:
482                         retval = uinput_set_bit(arg, ledbit, LED_MAX);
483                         break;
484
485                 case UI_SET_SNDBIT:
486                         retval = uinput_set_bit(arg, sndbit, SND_MAX);
487                         break;
488
489                 case UI_SET_FFBIT:
490                         retval = uinput_set_bit(arg, ffbit, FF_MAX);
491                         break;
492
493                 case UI_SET_SWBIT:
494                         retval = uinput_set_bit(arg, swbit, SW_MAX);
495                         break;
496
497                 case UI_SET_PHYS:
498                         if (udev->state == UIST_CREATED) {
499                                 retval = -EINVAL;
500                                 goto out;
501                         }
502                         length = strnlen_user(p, 1024);
503                         if (length <= 0) {
504                                 retval = -EFAULT;
505                                 break;
506                         }
507                         kfree(udev->dev->phys);
508                         udev->dev->phys = phys = kmalloc(length, GFP_KERNEL);
509                         if (!phys) {
510                                 retval = -ENOMEM;
511                                 break;
512                         }
513                         if (copy_from_user(phys, p, length)) {
514                                 udev->dev->phys = NULL;
515                                 kfree(phys);
516                                 retval = -EFAULT;
517                                 break;
518                         }
519                         phys[length - 1] = '\0';
520                         break;
521
522                 case UI_BEGIN_FF_UPLOAD:
523                         if (copy_from_user(&ff_up, p, sizeof(ff_up))) {
524                                 retval = -EFAULT;
525                                 break;
526                         }
527                         req = uinput_request_find(udev, ff_up.request_id);
528                         if (!(req && req->code == UI_FF_UPLOAD && req->u.effect)) {
529                                 retval = -EINVAL;
530                                 break;
531                         }
532                         ff_up.retval = 0;
533                         memcpy(&ff_up.effect, req->u.effect, sizeof(struct ff_effect));
534                         if (copy_to_user(p, &ff_up, sizeof(ff_up))) {
535                                 retval = -EFAULT;
536                                 break;
537                         }
538                         break;
539
540                 case UI_BEGIN_FF_ERASE:
541                         if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
542                                 retval = -EFAULT;
543                                 break;
544                         }
545                         req = uinput_request_find(udev, ff_erase.request_id);
546                         if (!(req && req->code == UI_FF_ERASE)) {
547                                 retval = -EINVAL;
548                                 break;
549                         }
550                         ff_erase.retval = 0;
551                         ff_erase.effect_id = req->u.effect_id;
552                         if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
553                                 retval = -EFAULT;
554                                 break;
555                         }
556                         break;
557
558                 case UI_END_FF_UPLOAD:
559                         if (copy_from_user(&ff_up, p, sizeof(ff_up))) {
560                                 retval = -EFAULT;
561                                 break;
562                         }
563                         req = uinput_request_find(udev, ff_up.request_id);
564                         if (!(req && req->code == UI_FF_UPLOAD && req->u.effect)) {
565                                 retval = -EINVAL;
566                                 break;
567                         }
568                         req->retval = ff_up.retval;
569                         memcpy(req->u.effect, &ff_up.effect, sizeof(struct ff_effect));
570                         uinput_request_done(udev, req);
571                         break;
572
573                 case UI_END_FF_ERASE:
574                         if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
575                                 retval = -EFAULT;
576                                 break;
577                         }
578                         req = uinput_request_find(udev, ff_erase.request_id);
579                         if (!(req && req->code == UI_FF_ERASE)) {
580                                 retval = -EINVAL;
581                                 break;
582                         }
583                         req->retval = ff_erase.retval;
584                         uinput_request_done(udev, req);
585                         break;
586
587                 default:
588                         retval = -EINVAL;
589         }
590
591  out:
592         mutex_unlock(&udev->mutex);
593         return retval;
594 }
595
596 static struct file_operations uinput_fops = {
597         .owner          = THIS_MODULE,
598         .open           = uinput_open,
599         .release        = uinput_release,
600         .read           = uinput_read,
601         .write          = uinput_write,
602         .poll           = uinput_poll,
603         .unlocked_ioctl = uinput_ioctl,
604 };
605
606 static struct miscdevice uinput_misc = {
607         .fops           = &uinput_fops,
608         .minor          = UINPUT_MINOR,
609         .name           = UINPUT_NAME,
610 };
611
612 static int __init uinput_init(void)
613 {
614         return misc_register(&uinput_misc);
615 }
616
617 static void __exit uinput_exit(void)
618 {
619         misc_deregister(&uinput_misc);
620 }
621
622 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
623 MODULE_DESCRIPTION("User level driver support for input subsystem");
624 MODULE_LICENSE("GPL");
625
626 module_init(uinput_init);
627 module_exit(uinput_exit);
628