xref: /openbmc/linux/drivers/input/misc/uinput.c (revision 4800cd83)
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 	char			*name;
351 	int			i, size;
352 	int			retval;
353 
354 	if (count != sizeof(struct uinput_user_dev))
355 		return -EINVAL;
356 
357 	if (!udev->dev) {
358 		retval = uinput_allocate_device(udev);
359 		if (retval)
360 			return retval;
361 	}
362 
363 	dev = udev->dev;
364 
365 	user_dev = kmalloc(sizeof(struct uinput_user_dev), GFP_KERNEL);
366 	if (!user_dev)
367 		return -ENOMEM;
368 
369 	if (copy_from_user(user_dev, buffer, sizeof(struct uinput_user_dev))) {
370 		retval = -EFAULT;
371 		goto exit;
372 	}
373 
374 	udev->ff_effects_max = user_dev->ff_effects_max;
375 
376 	size = strnlen(user_dev->name, UINPUT_MAX_NAME_SIZE) + 1;
377 	if (!size) {
378 		retval = -EINVAL;
379 		goto exit;
380 	}
381 
382 	kfree(dev->name);
383 	dev->name = name = kmalloc(size, GFP_KERNEL);
384 	if (!name) {
385 		retval = -ENOMEM;
386 		goto exit;
387 	}
388 	strlcpy(name, user_dev->name, size);
389 
390 	dev->id.bustype	= user_dev->id.bustype;
391 	dev->id.vendor	= user_dev->id.vendor;
392 	dev->id.product	= user_dev->id.product;
393 	dev->id.version	= user_dev->id.version;
394 
395 	for (i = 0; i < ABS_CNT; i++) {
396 		input_abs_set_max(dev, i, user_dev->absmax[i]);
397 		input_abs_set_min(dev, i, user_dev->absmin[i]);
398 		input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
399 		input_abs_set_flat(dev, i, user_dev->absflat[i]);
400 	}
401 
402 	/* check if absmin/absmax/absfuzz/absflat are filled as
403 	 * told in Documentation/input/input-programming.txt */
404 	if (test_bit(EV_ABS, dev->evbit)) {
405 		retval = uinput_validate_absbits(dev);
406 		if (retval < 0)
407 			goto exit;
408 		if (test_bit(ABS_MT_SLOT, dev->absbit)) {
409 			int nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
410 			input_mt_init_slots(dev, nslot);
411 		} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
412 			input_set_events_per_packet(dev, 60);
413 		}
414 	}
415 
416 	udev->state = UIST_SETUP_COMPLETE;
417 	retval = count;
418 
419  exit:
420 	kfree(user_dev);
421 	return retval;
422 }
423 
424 static inline ssize_t uinput_inject_event(struct uinput_device *udev, const char __user *buffer, size_t count)
425 {
426 	struct input_event ev;
427 
428 	if (count < input_event_size())
429 		return -EINVAL;
430 
431 	if (input_event_from_user(buffer, &ev))
432 		return -EFAULT;
433 
434 	input_event(udev->dev, ev.type, ev.code, ev.value);
435 
436 	return input_event_size();
437 }
438 
439 static ssize_t uinput_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
440 {
441 	struct uinput_device *udev = file->private_data;
442 	int retval;
443 
444 	retval = mutex_lock_interruptible(&udev->mutex);
445 	if (retval)
446 		return retval;
447 
448 	retval = udev->state == UIST_CREATED ?
449 			uinput_inject_event(udev, buffer, count) :
450 			uinput_setup_device(udev, buffer, count);
451 
452 	mutex_unlock(&udev->mutex);
453 
454 	return retval;
455 }
456 
457 static ssize_t uinput_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
458 {
459 	struct uinput_device *udev = file->private_data;
460 	int retval = 0;
461 
462 	if (udev->state != UIST_CREATED)
463 		return -ENODEV;
464 
465 	if (udev->head == udev->tail && (file->f_flags & O_NONBLOCK))
466 		return -EAGAIN;
467 
468 	retval = wait_event_interruptible(udev->waitq,
469 			udev->head != udev->tail || udev->state != UIST_CREATED);
470 	if (retval)
471 		return retval;
472 
473 	retval = mutex_lock_interruptible(&udev->mutex);
474 	if (retval)
475 		return retval;
476 
477 	if (udev->state != UIST_CREATED) {
478 		retval = -ENODEV;
479 		goto out;
480 	}
481 
482 	while (udev->head != udev->tail && retval + input_event_size() <= count) {
483 		if (input_event_to_user(buffer + retval, &udev->buff[udev->tail])) {
484 			retval = -EFAULT;
485 			goto out;
486 		}
487 		udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
488 		retval += input_event_size();
489 	}
490 
491  out:
492 	mutex_unlock(&udev->mutex);
493 
494 	return retval;
495 }
496 
497 static unsigned int uinput_poll(struct file *file, poll_table *wait)
498 {
499 	struct uinput_device *udev = file->private_data;
500 
501 	poll_wait(file, &udev->waitq, wait);
502 
503 	if (udev->head != udev->tail)
504 		return POLLIN | POLLRDNORM;
505 
506 	return 0;
507 }
508 
509 static int uinput_release(struct inode *inode, struct file *file)
510 {
511 	struct uinput_device *udev = file->private_data;
512 
513 	uinput_destroy_device(udev);
514 	kfree(udev);
515 
516 	return 0;
517 }
518 
519 #ifdef CONFIG_COMPAT
520 struct uinput_ff_upload_compat {
521 	int			request_id;
522 	int			retval;
523 	struct ff_effect_compat	effect;
524 	struct ff_effect_compat	old;
525 };
526 
527 static int uinput_ff_upload_to_user(char __user *buffer,
528 				    const struct uinput_ff_upload *ff_up)
529 {
530 	if (INPUT_COMPAT_TEST) {
531 		struct uinput_ff_upload_compat ff_up_compat;
532 
533 		ff_up_compat.request_id = ff_up->request_id;
534 		ff_up_compat.retval = ff_up->retval;
535 		/*
536 		 * It so happens that the pointer that gives us the trouble
537 		 * is the last field in the structure. Since we don't support
538 		 * custom waveforms in uinput anyway we can just copy the whole
539 		 * thing (to the compat size) and ignore the pointer.
540 		 */
541 		memcpy(&ff_up_compat.effect, &ff_up->effect,
542 			sizeof(struct ff_effect_compat));
543 		memcpy(&ff_up_compat.old, &ff_up->old,
544 			sizeof(struct ff_effect_compat));
545 
546 		if (copy_to_user(buffer, &ff_up_compat,
547 				 sizeof(struct uinput_ff_upload_compat)))
548 			return -EFAULT;
549 	} else {
550 		if (copy_to_user(buffer, ff_up,
551 				 sizeof(struct uinput_ff_upload)))
552 			return -EFAULT;
553 	}
554 
555 	return 0;
556 }
557 
558 static int uinput_ff_upload_from_user(const char __user *buffer,
559 				      struct uinput_ff_upload *ff_up)
560 {
561 	if (INPUT_COMPAT_TEST) {
562 		struct uinput_ff_upload_compat ff_up_compat;
563 
564 		if (copy_from_user(&ff_up_compat, buffer,
565 				   sizeof(struct uinput_ff_upload_compat)))
566 			return -EFAULT;
567 
568 		ff_up->request_id = ff_up_compat.request_id;
569 		ff_up->retval = ff_up_compat.retval;
570 		memcpy(&ff_up->effect, &ff_up_compat.effect,
571 			sizeof(struct ff_effect_compat));
572 		memcpy(&ff_up->old, &ff_up_compat.old,
573 			sizeof(struct ff_effect_compat));
574 
575 	} else {
576 		if (copy_from_user(ff_up, buffer,
577 				   sizeof(struct uinput_ff_upload)))
578 			return -EFAULT;
579 	}
580 
581 	return 0;
582 }
583 
584 #else
585 
586 static int uinput_ff_upload_to_user(char __user *buffer,
587 				    const struct uinput_ff_upload *ff_up)
588 {
589 	if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
590 		return -EFAULT;
591 
592 	return 0;
593 }
594 
595 static int uinput_ff_upload_from_user(const char __user *buffer,
596 				      struct uinput_ff_upload *ff_up)
597 {
598 	if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
599 		return -EFAULT;
600 
601 	return 0;
602 }
603 
604 #endif
605 
606 #define uinput_set_bit(_arg, _bit, _max)		\
607 ({							\
608 	int __ret = 0;					\
609 	if (udev->state == UIST_CREATED)		\
610 		__ret =  -EINVAL;			\
611 	else if ((_arg) > (_max))			\
612 		__ret = -EINVAL;			\
613 	else set_bit((_arg), udev->dev->_bit);		\
614 	__ret;						\
615 })
616 
617 static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
618 				 unsigned long arg, void __user *p)
619 {
620 	int			retval;
621 	struct uinput_device	*udev = file->private_data;
622 	struct uinput_ff_upload ff_up;
623 	struct uinput_ff_erase  ff_erase;
624 	struct uinput_request   *req;
625 	int                     length;
626 	char			*phys;
627 
628 	retval = mutex_lock_interruptible(&udev->mutex);
629 	if (retval)
630 		return retval;
631 
632 	if (!udev->dev) {
633 		retval = uinput_allocate_device(udev);
634 		if (retval)
635 			goto out;
636 	}
637 
638 	switch (cmd) {
639 		case UI_DEV_CREATE:
640 			retval = uinput_create_device(udev);
641 			break;
642 
643 		case UI_DEV_DESTROY:
644 			uinput_destroy_device(udev);
645 			break;
646 
647 		case UI_SET_EVBIT:
648 			retval = uinput_set_bit(arg, evbit, EV_MAX);
649 			break;
650 
651 		case UI_SET_KEYBIT:
652 			retval = uinput_set_bit(arg, keybit, KEY_MAX);
653 			break;
654 
655 		case UI_SET_RELBIT:
656 			retval = uinput_set_bit(arg, relbit, REL_MAX);
657 			break;
658 
659 		case UI_SET_ABSBIT:
660 			retval = uinput_set_bit(arg, absbit, ABS_MAX);
661 			break;
662 
663 		case UI_SET_MSCBIT:
664 			retval = uinput_set_bit(arg, mscbit, MSC_MAX);
665 			break;
666 
667 		case UI_SET_LEDBIT:
668 			retval = uinput_set_bit(arg, ledbit, LED_MAX);
669 			break;
670 
671 		case UI_SET_SNDBIT:
672 			retval = uinput_set_bit(arg, sndbit, SND_MAX);
673 			break;
674 
675 		case UI_SET_FFBIT:
676 			retval = uinput_set_bit(arg, ffbit, FF_MAX);
677 			break;
678 
679 		case UI_SET_SWBIT:
680 			retval = uinput_set_bit(arg, swbit, SW_MAX);
681 			break;
682 
683 		case UI_SET_PROPBIT:
684 			retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
685 			break;
686 
687 		case UI_SET_PHYS:
688 			if (udev->state == UIST_CREATED) {
689 				retval = -EINVAL;
690 				goto out;
691 			}
692 			length = strnlen_user(p, 1024);
693 			if (length <= 0) {
694 				retval = -EFAULT;
695 				break;
696 			}
697 			kfree(udev->dev->phys);
698 			udev->dev->phys = phys = kmalloc(length, GFP_KERNEL);
699 			if (!phys) {
700 				retval = -ENOMEM;
701 				break;
702 			}
703 			if (copy_from_user(phys, p, length)) {
704 				udev->dev->phys = NULL;
705 				kfree(phys);
706 				retval = -EFAULT;
707 				break;
708 			}
709 			phys[length - 1] = '\0';
710 			break;
711 
712 		case UI_BEGIN_FF_UPLOAD:
713 			retval = uinput_ff_upload_from_user(p, &ff_up);
714 			if (retval)
715 				break;
716 
717 			req = uinput_request_find(udev, ff_up.request_id);
718 			if (!req || req->code != UI_FF_UPLOAD || !req->u.upload.effect) {
719 				retval = -EINVAL;
720 				break;
721 			}
722 
723 			ff_up.retval = 0;
724 			ff_up.effect = *req->u.upload.effect;
725 			if (req->u.upload.old)
726 				ff_up.old = *req->u.upload.old;
727 			else
728 				memset(&ff_up.old, 0, sizeof(struct ff_effect));
729 
730 			retval = uinput_ff_upload_to_user(p, &ff_up);
731 			break;
732 
733 		case UI_BEGIN_FF_ERASE:
734 			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
735 				retval = -EFAULT;
736 				break;
737 			}
738 
739 			req = uinput_request_find(udev, ff_erase.request_id);
740 			if (!req || req->code != UI_FF_ERASE) {
741 				retval = -EINVAL;
742 				break;
743 			}
744 
745 			ff_erase.retval = 0;
746 			ff_erase.effect_id = req->u.effect_id;
747 			if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
748 				retval = -EFAULT;
749 				break;
750 			}
751 
752 			break;
753 
754 		case UI_END_FF_UPLOAD:
755 			retval = uinput_ff_upload_from_user(p, &ff_up);
756 			if (retval)
757 				break;
758 
759 			req = uinput_request_find(udev, ff_up.request_id);
760 			if (!req || req->code != UI_FF_UPLOAD ||
761 			    !req->u.upload.effect) {
762 				retval = -EINVAL;
763 				break;
764 			}
765 
766 			req->retval = ff_up.retval;
767 			uinput_request_done(udev, req);
768 			break;
769 
770 		case UI_END_FF_ERASE:
771 			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
772 				retval = -EFAULT;
773 				break;
774 			}
775 
776 			req = uinput_request_find(udev, ff_erase.request_id);
777 			if (!req || req->code != UI_FF_ERASE) {
778 				retval = -EINVAL;
779 				break;
780 			}
781 
782 			req->retval = ff_erase.retval;
783 			uinput_request_done(udev, req);
784 			break;
785 
786 		default:
787 			retval = -EINVAL;
788 	}
789 
790  out:
791 	mutex_unlock(&udev->mutex);
792 	return retval;
793 }
794 
795 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
796 {
797 	return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
798 }
799 
800 #ifdef CONFIG_COMPAT
801 static long uinput_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
802 {
803 	return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
804 }
805 #endif
806 
807 static const struct file_operations uinput_fops = {
808 	.owner		= THIS_MODULE,
809 	.open		= uinput_open,
810 	.release	= uinput_release,
811 	.read		= uinput_read,
812 	.write		= uinput_write,
813 	.poll		= uinput_poll,
814 	.unlocked_ioctl	= uinput_ioctl,
815 #ifdef CONFIG_COMPAT
816 	.compat_ioctl	= uinput_compat_ioctl,
817 #endif
818 	.llseek		= no_llseek,
819 };
820 
821 static struct miscdevice uinput_misc = {
822 	.fops		= &uinput_fops,
823 	.minor		= UINPUT_MINOR,
824 	.name		= UINPUT_NAME,
825 };
826 MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
827 MODULE_ALIAS("devname:" UINPUT_NAME);
828 
829 static int __init uinput_init(void)
830 {
831 	return misc_register(&uinput_misc);
832 }
833 
834 static void __exit uinput_exit(void)
835 {
836 	misc_deregister(&uinput_misc);
837 }
838 
839 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
840 MODULE_DESCRIPTION("User level driver support for input subsystem");
841 MODULE_LICENSE("GPL");
842 MODULE_VERSION("0.3");
843 
844 module_init(uinput_init);
845 module_exit(uinput_exit);
846 
847