xref: /openbmc/linux/drivers/input/misc/uinput.c (revision 81c2a3ba)
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/sched.h>
34 #include <linux/slab.h>
35 #include <linux/module.h>
36 #include <linux/init.h>
37 #include <linux/fs.h>
38 #include <linux/miscdevice.h>
39 #include <linux/uinput.h>
40 #include "../input-compat.h"
41 
42 static int uinput_dev_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
43 {
44 	struct uinput_device	*udev = input_get_drvdata(dev);
45 
46 	udev->buff[udev->head].type = type;
47 	udev->buff[udev->head].code = code;
48 	udev->buff[udev->head].value = value;
49 	do_gettimeofday(&udev->buff[udev->head].time);
50 	udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
51 
52 	wake_up_interruptible(&udev->waitq);
53 
54 	return 0;
55 }
56 
57 /* Atomically allocate an ID for the given request. Returns 0 on success. */
58 static int uinput_request_alloc_id(struct uinput_device *udev, struct uinput_request *request)
59 {
60 	int id;
61 	int err = -1;
62 
63 	spin_lock(&udev->requests_lock);
64 
65 	for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
66 		if (!udev->requests[id]) {
67 			request->id = id;
68 			udev->requests[id] = request;
69 			err = 0;
70 			break;
71 		}
72 	}
73 
74 	spin_unlock(&udev->requests_lock);
75 	return err;
76 }
77 
78 static struct uinput_request *uinput_request_find(struct uinput_device *udev, int id)
79 {
80 	/* Find an input request, by ID. Returns NULL if the ID isn't valid. */
81 	if (id >= UINPUT_NUM_REQUESTS || id < 0)
82 		return NULL;
83 
84 	return udev->requests[id];
85 }
86 
87 static inline int uinput_request_reserve_slot(struct uinput_device *udev, struct uinput_request *request)
88 {
89 	/* Allocate slot. If none are available right away, wait. */
90 	return wait_event_interruptible(udev->requests_waitq,
91 					!uinput_request_alloc_id(udev, request));
92 }
93 
94 static void uinput_request_done(struct uinput_device *udev, struct uinput_request *request)
95 {
96 	/* Mark slot as available */
97 	udev->requests[request->id] = NULL;
98 	wake_up(&udev->requests_waitq);
99 
100 	complete(&request->done);
101 }
102 
103 static int uinput_request_submit(struct uinput_device *udev, struct uinput_request *request)
104 {
105 	int retval;
106 
107 	retval = uinput_request_reserve_slot(udev, request);
108 	if (retval)
109 		return retval;
110 
111 	retval = mutex_lock_interruptible(&udev->mutex);
112 	if (retval)
113 		return retval;
114 
115 	if (udev->state != UIST_CREATED) {
116 		retval = -ENODEV;
117 		goto out;
118 	}
119 
120 	/* Tell our userspace app about this new request by queueing an input event */
121 	uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
122 
123  out:
124 	mutex_unlock(&udev->mutex);
125 	return retval;
126 }
127 
128 /*
129  * Fail all ouitstanding requests so handlers don't wait for the userspace
130  * to finish processing them.
131  */
132 static void uinput_flush_requests(struct uinput_device *udev)
133 {
134 	struct uinput_request *request;
135 	int i;
136 
137 	spin_lock(&udev->requests_lock);
138 
139 	for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
140 		request = udev->requests[i];
141 		if (request) {
142 			request->retval = -ENODEV;
143 			uinput_request_done(udev, request);
144 		}
145 	}
146 
147 	spin_unlock(&udev->requests_lock);
148 }
149 
150 static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
151 {
152 	uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
153 }
154 
155 static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
156 {
157 	uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
158 }
159 
160 static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
161 {
162 	return uinput_dev_event(dev, EV_FF, effect_id, value);
163 }
164 
165 static int uinput_dev_upload_effect(struct input_dev *dev, struct ff_effect *effect, struct ff_effect *old)
166 {
167 	struct uinput_device *udev = input_get_drvdata(dev);
168 	struct uinput_request request;
169 	int retval;
170 
171 	/*
172 	 * uinput driver does not currently support periodic effects with
173 	 * custom waveform since it does not have a way to pass buffer of
174 	 * samples (custom_data) to userspace. If ever there is a device
175 	 * supporting custom waveforms we would need to define an additional
176 	 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
177 	 */
178 	if (effect->type == FF_PERIODIC &&
179 			effect->u.periodic.waveform == FF_CUSTOM)
180 		return -EINVAL;
181 
182 	request.id = -1;
183 	init_completion(&request.done);
184 	request.code = UI_FF_UPLOAD;
185 	request.u.upload.effect = effect;
186 	request.u.upload.old = old;
187 
188 	retval = uinput_request_submit(udev, &request);
189 	if (!retval) {
190 		wait_for_completion(&request.done);
191 		retval = request.retval;
192 	}
193 
194 	return retval;
195 }
196 
197 static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
198 {
199 	struct uinput_device *udev = input_get_drvdata(dev);
200 	struct uinput_request request;
201 	int retval;
202 
203 	if (!test_bit(EV_FF, dev->evbit))
204 		return -ENOSYS;
205 
206 	request.id = -1;
207 	init_completion(&request.done);
208 	request.code = UI_FF_ERASE;
209 	request.u.effect_id = effect_id;
210 
211 	retval = uinput_request_submit(udev, &request);
212 	if (!retval) {
213 		wait_for_completion(&request.done);
214 		retval = request.retval;
215 	}
216 
217 	return retval;
218 }
219 
220 static void uinput_destroy_device(struct uinput_device *udev)
221 {
222 	const char *name, *phys;
223 	struct input_dev *dev = udev->dev;
224 	enum uinput_state old_state = udev->state;
225 
226 	udev->state = UIST_NEW_DEVICE;
227 
228 	if (dev) {
229 		name = dev->name;
230 		phys = dev->phys;
231 		if (old_state == UIST_CREATED) {
232 			uinput_flush_requests(udev);
233 			input_unregister_device(dev);
234 		} else {
235 			input_free_device(dev);
236 		}
237 		kfree(name);
238 		kfree(phys);
239 		udev->dev = NULL;
240 	}
241 }
242 
243 static int uinput_create_device(struct uinput_device *udev)
244 {
245 	struct input_dev *dev = udev->dev;
246 	int error;
247 
248 	if (udev->state != UIST_SETUP_COMPLETE) {
249 		printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
250 		return -EINVAL;
251 	}
252 
253 	if (udev->ff_effects_max) {
254 		error = input_ff_create(dev, udev->ff_effects_max);
255 		if (error)
256 			goto fail1;
257 
258 		dev->ff->upload = uinput_dev_upload_effect;
259 		dev->ff->erase = uinput_dev_erase_effect;
260 		dev->ff->playback = uinput_dev_playback;
261 		dev->ff->set_gain = uinput_dev_set_gain;
262 		dev->ff->set_autocenter = uinput_dev_set_autocenter;
263 	}
264 
265 	error = input_register_device(udev->dev);
266 	if (error)
267 		goto fail2;
268 
269 	udev->state = UIST_CREATED;
270 
271 	return 0;
272 
273  fail2:	input_ff_destroy(dev);
274  fail1: uinput_destroy_device(udev);
275 	return error;
276 }
277 
278 static int uinput_open(struct inode *inode, struct file *file)
279 {
280 	struct uinput_device *newdev;
281 
282 	newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
283 	if (!newdev)
284 		return -ENOMEM;
285 
286 	mutex_init(&newdev->mutex);
287 	spin_lock_init(&newdev->requests_lock);
288 	init_waitqueue_head(&newdev->requests_waitq);
289 	init_waitqueue_head(&newdev->waitq);
290 	newdev->state = UIST_NEW_DEVICE;
291 
292 	file->private_data = newdev;
293 	nonseekable_open(inode, file);
294 
295 	return 0;
296 }
297 
298 static int uinput_validate_absbits(struct input_dev *dev)
299 {
300 	unsigned int cnt;
301 	int retval = 0;
302 
303 	for (cnt = 0; cnt < ABS_CNT; cnt++) {
304 		if (!test_bit(cnt, dev->absbit))
305 			continue;
306 
307 		if ((dev->absmax[cnt] <= dev->absmin[cnt])) {
308 			printk(KERN_DEBUG
309 				"%s: invalid abs[%02x] min:%d max:%d\n",
310 				UINPUT_NAME, cnt,
311 				dev->absmin[cnt], dev->absmax[cnt]);
312 			retval = -EINVAL;
313 			break;
314 		}
315 
316 		if (dev->absflat[cnt] > (dev->absmax[cnt] - dev->absmin[cnt])) {
317 			printk(KERN_DEBUG
318 				"%s: absflat[%02x] out of range: %d "
319 				"(min:%d/max:%d)\n",
320 				UINPUT_NAME, cnt, dev->absflat[cnt],
321 				dev->absmin[cnt], dev->absmax[cnt]);
322 			retval = -EINVAL;
323 			break;
324 		}
325 	}
326 	return retval;
327 }
328 
329 static int uinput_allocate_device(struct uinput_device *udev)
330 {
331 	udev->dev = input_allocate_device();
332 	if (!udev->dev)
333 		return -ENOMEM;
334 
335 	udev->dev->event = uinput_dev_event;
336 	input_set_drvdata(udev->dev, udev);
337 
338 	return 0;
339 }
340 
341 static int uinput_setup_device(struct uinput_device *udev, const char __user *buffer, size_t count)
342 {
343 	struct uinput_user_dev	*user_dev;
344 	struct input_dev	*dev;
345 	char			*name;
346 	int			size;
347 	int			retval;
348 
349 	if (count != sizeof(struct uinput_user_dev))
350 		return -EINVAL;
351 
352 	if (!udev->dev) {
353 		retval = uinput_allocate_device(udev);
354 		if (retval)
355 			return retval;
356 	}
357 
358 	dev = udev->dev;
359 
360 	user_dev = kmalloc(sizeof(struct uinput_user_dev), GFP_KERNEL);
361 	if (!user_dev)
362 		return -ENOMEM;
363 
364 	if (copy_from_user(user_dev, buffer, sizeof(struct uinput_user_dev))) {
365 		retval = -EFAULT;
366 		goto exit;
367 	}
368 
369 	udev->ff_effects_max = user_dev->ff_effects_max;
370 
371 	size = strnlen(user_dev->name, UINPUT_MAX_NAME_SIZE) + 1;
372 	if (!size) {
373 		retval = -EINVAL;
374 		goto exit;
375 	}
376 
377 	kfree(dev->name);
378 	dev->name = name = kmalloc(size, GFP_KERNEL);
379 	if (!name) {
380 		retval = -ENOMEM;
381 		goto exit;
382 	}
383 	strlcpy(name, user_dev->name, size);
384 
385 	dev->id.bustype	= user_dev->id.bustype;
386 	dev->id.vendor	= user_dev->id.vendor;
387 	dev->id.product	= user_dev->id.product;
388 	dev->id.version	= user_dev->id.version;
389 
390 	size = sizeof(int) * ABS_CNT;
391 	memcpy(dev->absmax, user_dev->absmax, size);
392 	memcpy(dev->absmin, user_dev->absmin, size);
393 	memcpy(dev->absfuzz, user_dev->absfuzz, size);
394 	memcpy(dev->absflat, user_dev->absflat, size);
395 
396 	/* check if absmin/absmax/absfuzz/absflat are filled as
397 	 * told in Documentation/input/input-programming.txt */
398 	if (test_bit(EV_ABS, dev->evbit)) {
399 		retval = uinput_validate_absbits(dev);
400 		if (retval < 0)
401 			goto exit;
402 	}
403 
404 	udev->state = UIST_SETUP_COMPLETE;
405 	retval = count;
406 
407  exit:
408 	kfree(user_dev);
409 	return retval;
410 }
411 
412 static inline ssize_t uinput_inject_event(struct uinput_device *udev, const char __user *buffer, size_t count)
413 {
414 	struct input_event ev;
415 
416 	if (count < input_event_size())
417 		return -EINVAL;
418 
419 	if (input_event_from_user(buffer, &ev))
420 		return -EFAULT;
421 
422 	input_event(udev->dev, ev.type, ev.code, ev.value);
423 
424 	return input_event_size();
425 }
426 
427 static ssize_t uinput_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
428 {
429 	struct uinput_device *udev = file->private_data;
430 	int retval;
431 
432 	retval = mutex_lock_interruptible(&udev->mutex);
433 	if (retval)
434 		return retval;
435 
436 	retval = udev->state == UIST_CREATED ?
437 			uinput_inject_event(udev, buffer, count) :
438 			uinput_setup_device(udev, buffer, count);
439 
440 	mutex_unlock(&udev->mutex);
441 
442 	return retval;
443 }
444 
445 static ssize_t uinput_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
446 {
447 	struct uinput_device *udev = file->private_data;
448 	int retval = 0;
449 
450 	if (udev->state != UIST_CREATED)
451 		return -ENODEV;
452 
453 	if (udev->head == udev->tail && (file->f_flags & O_NONBLOCK))
454 		return -EAGAIN;
455 
456 	retval = wait_event_interruptible(udev->waitq,
457 			udev->head != udev->tail || udev->state != UIST_CREATED);
458 	if (retval)
459 		return retval;
460 
461 	retval = mutex_lock_interruptible(&udev->mutex);
462 	if (retval)
463 		return retval;
464 
465 	if (udev->state != UIST_CREATED) {
466 		retval = -ENODEV;
467 		goto out;
468 	}
469 
470 	while (udev->head != udev->tail && retval + input_event_size() <= count) {
471 		if (input_event_to_user(buffer + retval, &udev->buff[udev->tail])) {
472 			retval = -EFAULT;
473 			goto out;
474 		}
475 		udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
476 		retval += input_event_size();
477 	}
478 
479  out:
480 	mutex_unlock(&udev->mutex);
481 
482 	return retval;
483 }
484 
485 static unsigned int uinput_poll(struct file *file, poll_table *wait)
486 {
487 	struct uinput_device *udev = file->private_data;
488 
489 	poll_wait(file, &udev->waitq, wait);
490 
491 	if (udev->head != udev->tail)
492 		return POLLIN | POLLRDNORM;
493 
494 	return 0;
495 }
496 
497 static int uinput_release(struct inode *inode, struct file *file)
498 {
499 	struct uinput_device *udev = file->private_data;
500 
501 	uinput_destroy_device(udev);
502 	kfree(udev);
503 
504 	return 0;
505 }
506 
507 #ifdef CONFIG_COMPAT
508 struct uinput_ff_upload_compat {
509 	int			request_id;
510 	int			retval;
511 	struct ff_effect_compat	effect;
512 	struct ff_effect_compat	old;
513 };
514 
515 static int uinput_ff_upload_to_user(char __user *buffer,
516 				    const struct uinput_ff_upload *ff_up)
517 {
518 	if (INPUT_COMPAT_TEST) {
519 		struct uinput_ff_upload_compat ff_up_compat;
520 
521 		ff_up_compat.request_id = ff_up->request_id;
522 		ff_up_compat.retval = ff_up->retval;
523 		/*
524 		 * It so happens that the pointer that gives us the trouble
525 		 * is the last field in the structure. Since we don't support
526 		 * custom waveforms in uinput anyway we can just copy the whole
527 		 * thing (to the compat size) and ignore the pointer.
528 		 */
529 		memcpy(&ff_up_compat.effect, &ff_up->effect,
530 			sizeof(struct ff_effect_compat));
531 		memcpy(&ff_up_compat.old, &ff_up->old,
532 			sizeof(struct ff_effect_compat));
533 
534 		if (copy_to_user(buffer, &ff_up_compat,
535 				 sizeof(struct uinput_ff_upload_compat)))
536 			return -EFAULT;
537 	} else {
538 		if (copy_to_user(buffer, ff_up,
539 				 sizeof(struct uinput_ff_upload)))
540 			return -EFAULT;
541 	}
542 
543 	return 0;
544 }
545 
546 static int uinput_ff_upload_from_user(const char __user *buffer,
547 				      struct uinput_ff_upload *ff_up)
548 {
549 	if (INPUT_COMPAT_TEST) {
550 		struct uinput_ff_upload_compat ff_up_compat;
551 
552 		if (copy_from_user(&ff_up_compat, buffer,
553 				   sizeof(struct uinput_ff_upload_compat)))
554 			return -EFAULT;
555 
556 		ff_up->request_id = ff_up_compat.request_id;
557 		ff_up->retval = ff_up_compat.retval;
558 		memcpy(&ff_up->effect, &ff_up_compat.effect,
559 			sizeof(struct ff_effect_compat));
560 		memcpy(&ff_up->old, &ff_up_compat.old,
561 			sizeof(struct ff_effect_compat));
562 
563 	} else {
564 		if (copy_from_user(ff_up, buffer,
565 				   sizeof(struct uinput_ff_upload)))
566 			return -EFAULT;
567 	}
568 
569 	return 0;
570 }
571 
572 #else
573 
574 static int uinput_ff_upload_to_user(char __user *buffer,
575 				    const struct uinput_ff_upload *ff_up)
576 {
577 	if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
578 		return -EFAULT;
579 
580 	return 0;
581 }
582 
583 static int uinput_ff_upload_from_user(const char __user *buffer,
584 				      struct uinput_ff_upload *ff_up)
585 {
586 	if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
587 		return -EFAULT;
588 
589 	return 0;
590 }
591 
592 #endif
593 
594 #define uinput_set_bit(_arg, _bit, _max)		\
595 ({							\
596 	int __ret = 0;					\
597 	if (udev->state == UIST_CREATED)		\
598 		__ret =  -EINVAL;			\
599 	else if ((_arg) > (_max))			\
600 		__ret = -EINVAL;			\
601 	else set_bit((_arg), udev->dev->_bit);		\
602 	__ret;						\
603 })
604 
605 static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
606 				 unsigned long arg, void __user *p)
607 {
608 	int			retval;
609 	struct uinput_device	*udev = file->private_data;
610 	struct uinput_ff_upload ff_up;
611 	struct uinput_ff_erase  ff_erase;
612 	struct uinput_request   *req;
613 	int                     length;
614 	char			*phys;
615 
616 	retval = mutex_lock_interruptible(&udev->mutex);
617 	if (retval)
618 		return retval;
619 
620 	if (!udev->dev) {
621 		retval = uinput_allocate_device(udev);
622 		if (retval)
623 			goto out;
624 	}
625 
626 	switch (cmd) {
627 		case UI_DEV_CREATE:
628 			retval = uinput_create_device(udev);
629 			break;
630 
631 		case UI_DEV_DESTROY:
632 			uinput_destroy_device(udev);
633 			break;
634 
635 		case UI_SET_EVBIT:
636 			retval = uinput_set_bit(arg, evbit, EV_MAX);
637 			break;
638 
639 		case UI_SET_KEYBIT:
640 			retval = uinput_set_bit(arg, keybit, KEY_MAX);
641 			break;
642 
643 		case UI_SET_RELBIT:
644 			retval = uinput_set_bit(arg, relbit, REL_MAX);
645 			break;
646 
647 		case UI_SET_ABSBIT:
648 			retval = uinput_set_bit(arg, absbit, ABS_MAX);
649 			break;
650 
651 		case UI_SET_MSCBIT:
652 			retval = uinput_set_bit(arg, mscbit, MSC_MAX);
653 			break;
654 
655 		case UI_SET_LEDBIT:
656 			retval = uinput_set_bit(arg, ledbit, LED_MAX);
657 			break;
658 
659 		case UI_SET_SNDBIT:
660 			retval = uinput_set_bit(arg, sndbit, SND_MAX);
661 			break;
662 
663 		case UI_SET_FFBIT:
664 			retval = uinput_set_bit(arg, ffbit, FF_MAX);
665 			break;
666 
667 		case UI_SET_SWBIT:
668 			retval = uinput_set_bit(arg, swbit, SW_MAX);
669 			break;
670 
671 		case UI_SET_PHYS:
672 			if (udev->state == UIST_CREATED) {
673 				retval = -EINVAL;
674 				goto out;
675 			}
676 			length = strnlen_user(p, 1024);
677 			if (length <= 0) {
678 				retval = -EFAULT;
679 				break;
680 			}
681 			kfree(udev->dev->phys);
682 			udev->dev->phys = phys = kmalloc(length, GFP_KERNEL);
683 			if (!phys) {
684 				retval = -ENOMEM;
685 				break;
686 			}
687 			if (copy_from_user(phys, p, length)) {
688 				udev->dev->phys = NULL;
689 				kfree(phys);
690 				retval = -EFAULT;
691 				break;
692 			}
693 			phys[length - 1] = '\0';
694 			break;
695 
696 		case UI_BEGIN_FF_UPLOAD:
697 			retval = uinput_ff_upload_from_user(p, &ff_up);
698 			if (retval)
699 				break;
700 
701 			req = uinput_request_find(udev, ff_up.request_id);
702 			if (!req || req->code != UI_FF_UPLOAD || !req->u.upload.effect) {
703 				retval = -EINVAL;
704 				break;
705 			}
706 
707 			ff_up.retval = 0;
708 			ff_up.effect = *req->u.upload.effect;
709 			if (req->u.upload.old)
710 				ff_up.old = *req->u.upload.old;
711 			else
712 				memset(&ff_up.old, 0, sizeof(struct ff_effect));
713 
714 			retval = uinput_ff_upload_to_user(p, &ff_up);
715 			break;
716 
717 		case UI_BEGIN_FF_ERASE:
718 			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
719 				retval = -EFAULT;
720 				break;
721 			}
722 
723 			req = uinput_request_find(udev, ff_erase.request_id);
724 			if (!req || req->code != UI_FF_ERASE) {
725 				retval = -EINVAL;
726 				break;
727 			}
728 
729 			ff_erase.retval = 0;
730 			ff_erase.effect_id = req->u.effect_id;
731 			if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
732 				retval = -EFAULT;
733 				break;
734 			}
735 
736 			break;
737 
738 		case UI_END_FF_UPLOAD:
739 			retval = uinput_ff_upload_from_user(p, &ff_up);
740 			if (retval)
741 				break;
742 
743 			req = uinput_request_find(udev, ff_up.request_id);
744 			if (!req || req->code != UI_FF_UPLOAD ||
745 			    !req->u.upload.effect) {
746 				retval = -EINVAL;
747 				break;
748 			}
749 
750 			req->retval = ff_up.retval;
751 			uinput_request_done(udev, req);
752 			break;
753 
754 		case UI_END_FF_ERASE:
755 			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
756 				retval = -EFAULT;
757 				break;
758 			}
759 
760 			req = uinput_request_find(udev, ff_erase.request_id);
761 			if (!req || req->code != UI_FF_ERASE) {
762 				retval = -EINVAL;
763 				break;
764 			}
765 
766 			req->retval = ff_erase.retval;
767 			uinput_request_done(udev, req);
768 			break;
769 
770 		default:
771 			retval = -EINVAL;
772 	}
773 
774  out:
775 	mutex_unlock(&udev->mutex);
776 	return retval;
777 }
778 
779 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
780 {
781 	return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
782 }
783 
784 #ifdef CONFIG_COMPAT
785 static long uinput_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
786 {
787 	return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
788 }
789 #endif
790 
791 static const struct file_operations uinput_fops = {
792 	.owner		= THIS_MODULE,
793 	.open		= uinput_open,
794 	.release	= uinput_release,
795 	.read		= uinput_read,
796 	.write		= uinput_write,
797 	.poll		= uinput_poll,
798 	.unlocked_ioctl	= uinput_ioctl,
799 #ifdef CONFIG_COMPAT
800 	.compat_ioctl	= uinput_compat_ioctl,
801 #endif
802 };
803 
804 static struct miscdevice uinput_misc = {
805 	.fops		= &uinput_fops,
806 	.minor		= UINPUT_MINOR,
807 	.name		= UINPUT_NAME,
808 };
809 
810 static int __init uinput_init(void)
811 {
812 	return misc_register(&uinput_misc);
813 }
814 
815 static void __exit uinput_exit(void)
816 {
817 	misc_deregister(&uinput_misc);
818 }
819 
820 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
821 MODULE_DESCRIPTION("User level driver support for input subsystem");
822 MODULE_LICENSE("GPL");
823 MODULE_VERSION("0.3");
824 
825 module_init(uinput_init);
826 module_exit(uinput_exit);
827 
828