xref: /linux/drivers/input/misc/uinput.c (revision 9d9659b6c0ebf7dde65ebada4c67980818245913)
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 <linux/input/mt.h>
41 #include "../input-compat.h"
42 
43 static int uinput_dev_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
44 {
45 	struct uinput_device	*udev = input_get_drvdata(dev);
46 
47 	udev->buff[udev->head].type = type;
48 	udev->buff[udev->head].code = code;
49 	udev->buff[udev->head].value = value;
50 	do_gettimeofday(&udev->buff[udev->head].time);
51 	udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
52 
53 	wake_up_interruptible(&udev->waitq);
54 
55 	return 0;
56 }
57 
58 /* Atomically allocate an ID for the given request. Returns 0 on success. */
59 static int uinput_request_alloc_id(struct uinput_device *udev, struct uinput_request *request)
60 {
61 	int id;
62 	int err = -1;
63 
64 	spin_lock(&udev->requests_lock);
65 
66 	for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
67 		if (!udev->requests[id]) {
68 			request->id = id;
69 			udev->requests[id] = request;
70 			err = 0;
71 			break;
72 		}
73 	}
74 
75 	spin_unlock(&udev->requests_lock);
76 	return err;
77 }
78 
79 static struct uinput_request *uinput_request_find(struct uinput_device *udev, int id)
80 {
81 	/* Find an input request, by ID. Returns NULL if the ID isn't valid. */
82 	if (id >= UINPUT_NUM_REQUESTS || id < 0)
83 		return NULL;
84 
85 	return udev->requests[id];
86 }
87 
88 static inline int uinput_request_reserve_slot(struct uinput_device *udev, struct uinput_request *request)
89 {
90 	/* Allocate slot. If none are available right away, wait. */
91 	return wait_event_interruptible(udev->requests_waitq,
92 					!uinput_request_alloc_id(udev, request));
93 }
94 
95 static void uinput_request_done(struct uinput_device *udev, struct uinput_request *request)
96 {
97 	/* Mark slot as available */
98 	udev->requests[request->id] = NULL;
99 	wake_up(&udev->requests_waitq);
100 
101 	complete(&request->done);
102 }
103 
104 static int uinput_request_submit(struct uinput_device *udev, struct uinput_request *request)
105 {
106 	int retval;
107 
108 	retval = uinput_request_reserve_slot(udev, request);
109 	if (retval)
110 		return retval;
111 
112 	retval = mutex_lock_interruptible(&udev->mutex);
113 	if (retval)
114 		return retval;
115 
116 	if (udev->state != UIST_CREATED) {
117 		retval = -ENODEV;
118 		goto out;
119 	}
120 
121 	/* Tell our userspace app about this new request by queueing an input event */
122 	uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
123 
124  out:
125 	mutex_unlock(&udev->mutex);
126 	return retval;
127 }
128 
129 /*
130  * Fail all ouitstanding requests so handlers don't wait for the userspace
131  * to finish processing them.
132  */
133 static void uinput_flush_requests(struct uinput_device *udev)
134 {
135 	struct uinput_request *request;
136 	int i;
137 
138 	spin_lock(&udev->requests_lock);
139 
140 	for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
141 		request = udev->requests[i];
142 		if (request) {
143 			request->retval = -ENODEV;
144 			uinput_request_done(udev, request);
145 		}
146 	}
147 
148 	spin_unlock(&udev->requests_lock);
149 }
150 
151 static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
152 {
153 	uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
154 }
155 
156 static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
157 {
158 	uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
159 }
160 
161 static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
162 {
163 	return uinput_dev_event(dev, EV_FF, effect_id, value);
164 }
165 
166 static int uinput_dev_upload_effect(struct input_dev *dev, struct ff_effect *effect, struct ff_effect *old)
167 {
168 	struct uinput_device *udev = input_get_drvdata(dev);
169 	struct uinput_request request;
170 	int retval;
171 
172 	/*
173 	 * uinput driver does not currently support periodic effects with
174 	 * custom waveform since it does not have a way to pass buffer of
175 	 * samples (custom_data) to userspace. If ever there is a device
176 	 * supporting custom waveforms we would need to define an additional
177 	 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
178 	 */
179 	if (effect->type == FF_PERIODIC &&
180 			effect->u.periodic.waveform == FF_CUSTOM)
181 		return -EINVAL;
182 
183 	request.id = -1;
184 	init_completion(&request.done);
185 	request.code = UI_FF_UPLOAD;
186 	request.u.upload.effect = effect;
187 	request.u.upload.old = old;
188 
189 	retval = uinput_request_submit(udev, &request);
190 	if (!retval) {
191 		wait_for_completion(&request.done);
192 		retval = request.retval;
193 	}
194 
195 	return retval;
196 }
197 
198 static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
199 {
200 	struct uinput_device *udev = input_get_drvdata(dev);
201 	struct uinput_request request;
202 	int retval;
203 
204 	if (!test_bit(EV_FF, dev->evbit))
205 		return -ENOSYS;
206 
207 	request.id = -1;
208 	init_completion(&request.done);
209 	request.code = UI_FF_ERASE;
210 	request.u.effect_id = effect_id;
211 
212 	retval = uinput_request_submit(udev, &request);
213 	if (!retval) {
214 		wait_for_completion(&request.done);
215 		retval = request.retval;
216 	}
217 
218 	return retval;
219 }
220 
221 static void uinput_destroy_device(struct uinput_device *udev)
222 {
223 	const char *name, *phys;
224 	struct input_dev *dev = udev->dev;
225 	enum uinput_state old_state = udev->state;
226 
227 	udev->state = UIST_NEW_DEVICE;
228 
229 	if (dev) {
230 		name = dev->name;
231 		phys = dev->phys;
232 		if (old_state == UIST_CREATED) {
233 			uinput_flush_requests(udev);
234 			input_unregister_device(dev);
235 		} else {
236 			input_free_device(dev);
237 		}
238 		kfree(name);
239 		kfree(phys);
240 		udev->dev = NULL;
241 	}
242 }
243 
244 static int uinput_create_device(struct uinput_device *udev)
245 {
246 	struct input_dev *dev = udev->dev;
247 	int error;
248 
249 	if (udev->state != UIST_SETUP_COMPLETE) {
250 		printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
251 		return -EINVAL;
252 	}
253 
254 	if (udev->ff_effects_max) {
255 		error = input_ff_create(dev, udev->ff_effects_max);
256 		if (error)
257 			goto fail1;
258 
259 		dev->ff->upload = uinput_dev_upload_effect;
260 		dev->ff->erase = uinput_dev_erase_effect;
261 		dev->ff->playback = uinput_dev_playback;
262 		dev->ff->set_gain = uinput_dev_set_gain;
263 		dev->ff->set_autocenter = uinput_dev_set_autocenter;
264 	}
265 
266 	error = input_register_device(udev->dev);
267 	if (error)
268 		goto fail2;
269 
270 	udev->state = UIST_CREATED;
271 
272 	return 0;
273 
274  fail2:	input_ff_destroy(dev);
275  fail1: uinput_destroy_device(udev);
276 	return error;
277 }
278 
279 static int uinput_open(struct inode *inode, struct file *file)
280 {
281 	struct uinput_device *newdev;
282 
283 	newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
284 	if (!newdev)
285 		return -ENOMEM;
286 
287 	mutex_init(&newdev->mutex);
288 	spin_lock_init(&newdev->requests_lock);
289 	init_waitqueue_head(&newdev->requests_waitq);
290 	init_waitqueue_head(&newdev->waitq);
291 	newdev->state = UIST_NEW_DEVICE;
292 
293 	file->private_data = newdev;
294 	nonseekable_open(inode, file);
295 
296 	return 0;
297 }
298 
299 static int uinput_validate_absbits(struct input_dev *dev)
300 {
301 	unsigned int cnt;
302 	int retval = 0;
303 
304 	for (cnt = 0; cnt < ABS_CNT; cnt++) {
305 		if (!test_bit(cnt, dev->absbit))
306 			continue;
307 
308 		if (input_abs_get_max(dev, cnt) <= input_abs_get_min(dev, cnt)) {
309 			printk(KERN_DEBUG
310 				"%s: invalid abs[%02x] min:%d max:%d\n",
311 				UINPUT_NAME, cnt,
312 				input_abs_get_min(dev, cnt),
313 				input_abs_get_max(dev, cnt));
314 			retval = -EINVAL;
315 			break;
316 		}
317 
318 		if (input_abs_get_flat(dev, cnt) >
319 		    input_abs_get_max(dev, cnt) - input_abs_get_min(dev, cnt)) {
320 			printk(KERN_DEBUG
321 				"%s: abs_flat #%02x out of range: %d "
322 				"(min:%d/max:%d)\n",
323 				UINPUT_NAME, cnt,
324 				input_abs_get_flat(dev, cnt),
325 				input_abs_get_min(dev, cnt),
326 				input_abs_get_max(dev, cnt));
327 			retval = -EINVAL;
328 			break;
329 		}
330 	}
331 	return retval;
332 }
333 
334 static int uinput_allocate_device(struct uinput_device *udev)
335 {
336 	udev->dev = input_allocate_device();
337 	if (!udev->dev)
338 		return -ENOMEM;
339 
340 	udev->dev->event = uinput_dev_event;
341 	input_set_drvdata(udev->dev, udev);
342 
343 	return 0;
344 }
345 
346 static int uinput_setup_device(struct uinput_device *udev, const char __user *buffer, size_t count)
347 {
348 	struct uinput_user_dev	*user_dev;
349 	struct input_dev	*dev;
350 	int			i;
351 	int			retval;
352 
353 	if (count != sizeof(struct uinput_user_dev))
354 		return -EINVAL;
355 
356 	if (!udev->dev) {
357 		retval = uinput_allocate_device(udev);
358 		if (retval)
359 			return retval;
360 	}
361 
362 	dev = udev->dev;
363 
364 	user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
365 	if (IS_ERR(user_dev))
366 		return PTR_ERR(user_dev);
367 
368 	udev->ff_effects_max = user_dev->ff_effects_max;
369 
370 	/* Ensure name is filled in */
371 	if (!user_dev->name[0]) {
372 		retval = -EINVAL;
373 		goto exit;
374 	}
375 
376 	kfree(dev->name);
377 	dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
378 			     GFP_KERNEL);
379 	if (!dev->name) {
380 		retval = -ENOMEM;
381 		goto exit;
382 	}
383 
384 	dev->id.bustype	= user_dev->id.bustype;
385 	dev->id.vendor	= user_dev->id.vendor;
386 	dev->id.product	= user_dev->id.product;
387 	dev->id.version	= user_dev->id.version;
388 
389 	for (i = 0; i < ABS_CNT; i++) {
390 		input_abs_set_max(dev, i, user_dev->absmax[i]);
391 		input_abs_set_min(dev, i, user_dev->absmin[i]);
392 		input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
393 		input_abs_set_flat(dev, i, user_dev->absflat[i]);
394 	}
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 		if (test_bit(ABS_MT_SLOT, dev->absbit)) {
403 			int nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
404 			input_mt_init_slots(dev, nslot);
405 		} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
406 			input_set_events_per_packet(dev, 60);
407 		}
408 	}
409 
410 	udev->state = UIST_SETUP_COMPLETE;
411 	retval = count;
412 
413  exit:
414 	kfree(user_dev);
415 	return retval;
416 }
417 
418 static inline ssize_t uinput_inject_event(struct uinput_device *udev, const char __user *buffer, size_t count)
419 {
420 	struct input_event ev;
421 
422 	if (count < input_event_size())
423 		return -EINVAL;
424 
425 	if (input_event_from_user(buffer, &ev))
426 		return -EFAULT;
427 
428 	input_event(udev->dev, ev.type, ev.code, ev.value);
429 
430 	return input_event_size();
431 }
432 
433 static ssize_t uinput_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
434 {
435 	struct uinput_device *udev = file->private_data;
436 	int retval;
437 
438 	retval = mutex_lock_interruptible(&udev->mutex);
439 	if (retval)
440 		return retval;
441 
442 	retval = udev->state == UIST_CREATED ?
443 			uinput_inject_event(udev, buffer, count) :
444 			uinput_setup_device(udev, buffer, count);
445 
446 	mutex_unlock(&udev->mutex);
447 
448 	return retval;
449 }
450 
451 static ssize_t uinput_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
452 {
453 	struct uinput_device *udev = file->private_data;
454 	int retval = 0;
455 
456 	if (udev->state != UIST_CREATED)
457 		return -ENODEV;
458 
459 	if (udev->head == udev->tail && (file->f_flags & O_NONBLOCK))
460 		return -EAGAIN;
461 
462 	retval = wait_event_interruptible(udev->waitq,
463 			udev->head != udev->tail || udev->state != UIST_CREATED);
464 	if (retval)
465 		return retval;
466 
467 	retval = mutex_lock_interruptible(&udev->mutex);
468 	if (retval)
469 		return retval;
470 
471 	if (udev->state != UIST_CREATED) {
472 		retval = -ENODEV;
473 		goto out;
474 	}
475 
476 	while (udev->head != udev->tail && retval + input_event_size() <= count) {
477 		if (input_event_to_user(buffer + retval, &udev->buff[udev->tail])) {
478 			retval = -EFAULT;
479 			goto out;
480 		}
481 		udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
482 		retval += input_event_size();
483 	}
484 
485  out:
486 	mutex_unlock(&udev->mutex);
487 
488 	return retval;
489 }
490 
491 static unsigned int uinput_poll(struct file *file, poll_table *wait)
492 {
493 	struct uinput_device *udev = file->private_data;
494 
495 	poll_wait(file, &udev->waitq, wait);
496 
497 	if (udev->head != udev->tail)
498 		return POLLIN | POLLRDNORM;
499 
500 	return 0;
501 }
502 
503 static int uinput_release(struct inode *inode, struct file *file)
504 {
505 	struct uinput_device *udev = file->private_data;
506 
507 	uinput_destroy_device(udev);
508 	kfree(udev);
509 
510 	return 0;
511 }
512 
513 #ifdef CONFIG_COMPAT
514 struct uinput_ff_upload_compat {
515 	int			request_id;
516 	int			retval;
517 	struct ff_effect_compat	effect;
518 	struct ff_effect_compat	old;
519 };
520 
521 static int uinput_ff_upload_to_user(char __user *buffer,
522 				    const struct uinput_ff_upload *ff_up)
523 {
524 	if (INPUT_COMPAT_TEST) {
525 		struct uinput_ff_upload_compat ff_up_compat;
526 
527 		ff_up_compat.request_id = ff_up->request_id;
528 		ff_up_compat.retval = ff_up->retval;
529 		/*
530 		 * It so happens that the pointer that gives us the trouble
531 		 * is the last field in the structure. Since we don't support
532 		 * custom waveforms in uinput anyway we can just copy the whole
533 		 * thing (to the compat size) and ignore the pointer.
534 		 */
535 		memcpy(&ff_up_compat.effect, &ff_up->effect,
536 			sizeof(struct ff_effect_compat));
537 		memcpy(&ff_up_compat.old, &ff_up->old,
538 			sizeof(struct ff_effect_compat));
539 
540 		if (copy_to_user(buffer, &ff_up_compat,
541 				 sizeof(struct uinput_ff_upload_compat)))
542 			return -EFAULT;
543 	} else {
544 		if (copy_to_user(buffer, ff_up,
545 				 sizeof(struct uinput_ff_upload)))
546 			return -EFAULT;
547 	}
548 
549 	return 0;
550 }
551 
552 static int uinput_ff_upload_from_user(const char __user *buffer,
553 				      struct uinput_ff_upload *ff_up)
554 {
555 	if (INPUT_COMPAT_TEST) {
556 		struct uinput_ff_upload_compat ff_up_compat;
557 
558 		if (copy_from_user(&ff_up_compat, buffer,
559 				   sizeof(struct uinput_ff_upload_compat)))
560 			return -EFAULT;
561 
562 		ff_up->request_id = ff_up_compat.request_id;
563 		ff_up->retval = ff_up_compat.retval;
564 		memcpy(&ff_up->effect, &ff_up_compat.effect,
565 			sizeof(struct ff_effect_compat));
566 		memcpy(&ff_up->old, &ff_up_compat.old,
567 			sizeof(struct ff_effect_compat));
568 
569 	} else {
570 		if (copy_from_user(ff_up, buffer,
571 				   sizeof(struct uinput_ff_upload)))
572 			return -EFAULT;
573 	}
574 
575 	return 0;
576 }
577 
578 #else
579 
580 static int uinput_ff_upload_to_user(char __user *buffer,
581 				    const struct uinput_ff_upload *ff_up)
582 {
583 	if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
584 		return -EFAULT;
585 
586 	return 0;
587 }
588 
589 static int uinput_ff_upload_from_user(const char __user *buffer,
590 				      struct uinput_ff_upload *ff_up)
591 {
592 	if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
593 		return -EFAULT;
594 
595 	return 0;
596 }
597 
598 #endif
599 
600 #define uinput_set_bit(_arg, _bit, _max)		\
601 ({							\
602 	int __ret = 0;					\
603 	if (udev->state == UIST_CREATED)		\
604 		__ret =  -EINVAL;			\
605 	else if ((_arg) > (_max))			\
606 		__ret = -EINVAL;			\
607 	else set_bit((_arg), udev->dev->_bit);		\
608 	__ret;						\
609 })
610 
611 static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
612 				 unsigned long arg, void __user *p)
613 {
614 	int			retval;
615 	struct uinput_device	*udev = file->private_data;
616 	struct uinput_ff_upload ff_up;
617 	struct uinput_ff_erase  ff_erase;
618 	struct uinput_request   *req;
619 	char			*phys;
620 
621 	retval = mutex_lock_interruptible(&udev->mutex);
622 	if (retval)
623 		return retval;
624 
625 	if (!udev->dev) {
626 		retval = uinput_allocate_device(udev);
627 		if (retval)
628 			goto out;
629 	}
630 
631 	switch (cmd) {
632 		case UI_DEV_CREATE:
633 			retval = uinput_create_device(udev);
634 			break;
635 
636 		case UI_DEV_DESTROY:
637 			uinput_destroy_device(udev);
638 			break;
639 
640 		case UI_SET_EVBIT:
641 			retval = uinput_set_bit(arg, evbit, EV_MAX);
642 			break;
643 
644 		case UI_SET_KEYBIT:
645 			retval = uinput_set_bit(arg, keybit, KEY_MAX);
646 			break;
647 
648 		case UI_SET_RELBIT:
649 			retval = uinput_set_bit(arg, relbit, REL_MAX);
650 			break;
651 
652 		case UI_SET_ABSBIT:
653 			retval = uinput_set_bit(arg, absbit, ABS_MAX);
654 			break;
655 
656 		case UI_SET_MSCBIT:
657 			retval = uinput_set_bit(arg, mscbit, MSC_MAX);
658 			break;
659 
660 		case UI_SET_LEDBIT:
661 			retval = uinput_set_bit(arg, ledbit, LED_MAX);
662 			break;
663 
664 		case UI_SET_SNDBIT:
665 			retval = uinput_set_bit(arg, sndbit, SND_MAX);
666 			break;
667 
668 		case UI_SET_FFBIT:
669 			retval = uinput_set_bit(arg, ffbit, FF_MAX);
670 			break;
671 
672 		case UI_SET_SWBIT:
673 			retval = uinput_set_bit(arg, swbit, SW_MAX);
674 			break;
675 
676 		case UI_SET_PROPBIT:
677 			retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
678 			break;
679 
680 		case UI_SET_PHYS:
681 			if (udev->state == UIST_CREATED) {
682 				retval = -EINVAL;
683 				goto out;
684 			}
685 
686 			phys = strndup_user(p, 1024);
687 			if (IS_ERR(phys)) {
688 				retval = PTR_ERR(phys);
689 				goto out;
690 			}
691 
692 			kfree(udev->dev->phys);
693 			udev->dev->phys = phys;
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 	.llseek		= no_llseek,
803 };
804 
805 static struct miscdevice uinput_misc = {
806 	.fops		= &uinput_fops,
807 	.minor		= UINPUT_MINOR,
808 	.name		= UINPUT_NAME,
809 };
810 MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
811 MODULE_ALIAS("devname:" UINPUT_NAME);
812 
813 static int __init uinput_init(void)
814 {
815 	return misc_register(&uinput_misc);
816 }
817 
818 static void __exit uinput_exit(void)
819 {
820 	misc_deregister(&uinput_misc);
821 }
822 
823 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
824 MODULE_DESCRIPTION("User level driver support for input subsystem");
825 MODULE_LICENSE("GPL");
826 MODULE_VERSION("0.3");
827 
828 module_init(uinput_init);
829 module_exit(uinput_exit);
830 
831