xref: /linux/drivers/input/misc/uinput.c (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
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 		int min, max;
306 		if (!test_bit(cnt, dev->absbit))
307 			continue;
308 
309 		min = input_abs_get_min(dev, cnt);
310 		max = input_abs_get_max(dev, cnt);
311 
312 		if ((min != 0 || max != 0) && max <= min) {
313 			printk(KERN_DEBUG
314 				"%s: invalid abs[%02x] min:%d max:%d\n",
315 				UINPUT_NAME, cnt,
316 				input_abs_get_min(dev, cnt),
317 				input_abs_get_max(dev, cnt));
318 			retval = -EINVAL;
319 			break;
320 		}
321 
322 		if (input_abs_get_flat(dev, cnt) >
323 		    input_abs_get_max(dev, cnt) - input_abs_get_min(dev, cnt)) {
324 			printk(KERN_DEBUG
325 				"%s: abs_flat #%02x out of range: %d "
326 				"(min:%d/max:%d)\n",
327 				UINPUT_NAME, cnt,
328 				input_abs_get_flat(dev, cnt),
329 				input_abs_get_min(dev, cnt),
330 				input_abs_get_max(dev, cnt));
331 			retval = -EINVAL;
332 			break;
333 		}
334 	}
335 	return retval;
336 }
337 
338 static int uinput_allocate_device(struct uinput_device *udev)
339 {
340 	udev->dev = input_allocate_device();
341 	if (!udev->dev)
342 		return -ENOMEM;
343 
344 	udev->dev->event = uinput_dev_event;
345 	input_set_drvdata(udev->dev, udev);
346 
347 	return 0;
348 }
349 
350 static int uinput_setup_device(struct uinput_device *udev, const char __user *buffer, size_t count)
351 {
352 	struct uinput_user_dev	*user_dev;
353 	struct input_dev	*dev;
354 	int			i;
355 	int			retval;
356 
357 	if (count != sizeof(struct uinput_user_dev))
358 		return -EINVAL;
359 
360 	if (!udev->dev) {
361 		retval = uinput_allocate_device(udev);
362 		if (retval)
363 			return retval;
364 	}
365 
366 	dev = udev->dev;
367 
368 	user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
369 	if (IS_ERR(user_dev))
370 		return PTR_ERR(user_dev);
371 
372 	udev->ff_effects_max = user_dev->ff_effects_max;
373 
374 	/* Ensure name is filled in */
375 	if (!user_dev->name[0]) {
376 		retval = -EINVAL;
377 		goto exit;
378 	}
379 
380 	kfree(dev->name);
381 	dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
382 			     GFP_KERNEL);
383 	if (!dev->name) {
384 		retval = -ENOMEM;
385 		goto exit;
386 	}
387 
388 	dev->id.bustype	= user_dev->id.bustype;
389 	dev->id.vendor	= user_dev->id.vendor;
390 	dev->id.product	= user_dev->id.product;
391 	dev->id.version	= user_dev->id.version;
392 
393 	for (i = 0; i < ABS_CNT; i++) {
394 		input_abs_set_max(dev, i, user_dev->absmax[i]);
395 		input_abs_set_min(dev, i, user_dev->absmin[i]);
396 		input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
397 		input_abs_set_flat(dev, i, user_dev->absflat[i]);
398 	}
399 
400 	/* check if absmin/absmax/absfuzz/absflat are filled as
401 	 * told in Documentation/input/input-programming.txt */
402 	if (test_bit(EV_ABS, dev->evbit)) {
403 		retval = uinput_validate_absbits(dev);
404 		if (retval < 0)
405 			goto exit;
406 		if (test_bit(ABS_MT_SLOT, dev->absbit)) {
407 			int nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
408 			input_mt_init_slots(dev, nslot);
409 		} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
410 			input_set_events_per_packet(dev, 60);
411 		}
412 	}
413 
414 	udev->state = UIST_SETUP_COMPLETE;
415 	retval = count;
416 
417  exit:
418 	kfree(user_dev);
419 	return retval;
420 }
421 
422 static inline ssize_t uinput_inject_event(struct uinput_device *udev, const char __user *buffer, size_t count)
423 {
424 	struct input_event ev;
425 
426 	if (count < input_event_size())
427 		return -EINVAL;
428 
429 	if (input_event_from_user(buffer, &ev))
430 		return -EFAULT;
431 
432 	input_event(udev->dev, ev.type, ev.code, ev.value);
433 
434 	return input_event_size();
435 }
436 
437 static ssize_t uinput_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
438 {
439 	struct uinput_device *udev = file->private_data;
440 	int retval;
441 
442 	retval = mutex_lock_interruptible(&udev->mutex);
443 	if (retval)
444 		return retval;
445 
446 	retval = udev->state == UIST_CREATED ?
447 			uinput_inject_event(udev, buffer, count) :
448 			uinput_setup_device(udev, buffer, count);
449 
450 	mutex_unlock(&udev->mutex);
451 
452 	return retval;
453 }
454 
455 static ssize_t uinput_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
456 {
457 	struct uinput_device *udev = file->private_data;
458 	int retval = 0;
459 
460 	if (udev->state != UIST_CREATED)
461 		return -ENODEV;
462 
463 	if (udev->head == udev->tail && (file->f_flags & O_NONBLOCK))
464 		return -EAGAIN;
465 
466 	retval = wait_event_interruptible(udev->waitq,
467 			udev->head != udev->tail || udev->state != UIST_CREATED);
468 	if (retval)
469 		return retval;
470 
471 	retval = mutex_lock_interruptible(&udev->mutex);
472 	if (retval)
473 		return retval;
474 
475 	if (udev->state != UIST_CREATED) {
476 		retval = -ENODEV;
477 		goto out;
478 	}
479 
480 	while (udev->head != udev->tail && retval + input_event_size() <= count) {
481 		if (input_event_to_user(buffer + retval, &udev->buff[udev->tail])) {
482 			retval = -EFAULT;
483 			goto out;
484 		}
485 		udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
486 		retval += input_event_size();
487 	}
488 
489  out:
490 	mutex_unlock(&udev->mutex);
491 
492 	return retval;
493 }
494 
495 static unsigned int uinput_poll(struct file *file, poll_table *wait)
496 {
497 	struct uinput_device *udev = file->private_data;
498 
499 	poll_wait(file, &udev->waitq, wait);
500 
501 	if (udev->head != udev->tail)
502 		return POLLIN | POLLRDNORM;
503 
504 	return 0;
505 }
506 
507 static int uinput_release(struct inode *inode, struct file *file)
508 {
509 	struct uinput_device *udev = file->private_data;
510 
511 	uinput_destroy_device(udev);
512 	kfree(udev);
513 
514 	return 0;
515 }
516 
517 #ifdef CONFIG_COMPAT
518 struct uinput_ff_upload_compat {
519 	int			request_id;
520 	int			retval;
521 	struct ff_effect_compat	effect;
522 	struct ff_effect_compat	old;
523 };
524 
525 static int uinput_ff_upload_to_user(char __user *buffer,
526 				    const struct uinput_ff_upload *ff_up)
527 {
528 	if (INPUT_COMPAT_TEST) {
529 		struct uinput_ff_upload_compat ff_up_compat;
530 
531 		ff_up_compat.request_id = ff_up->request_id;
532 		ff_up_compat.retval = ff_up->retval;
533 		/*
534 		 * It so happens that the pointer that gives us the trouble
535 		 * is the last field in the structure. Since we don't support
536 		 * custom waveforms in uinput anyway we can just copy the whole
537 		 * thing (to the compat size) and ignore the pointer.
538 		 */
539 		memcpy(&ff_up_compat.effect, &ff_up->effect,
540 			sizeof(struct ff_effect_compat));
541 		memcpy(&ff_up_compat.old, &ff_up->old,
542 			sizeof(struct ff_effect_compat));
543 
544 		if (copy_to_user(buffer, &ff_up_compat,
545 				 sizeof(struct uinput_ff_upload_compat)))
546 			return -EFAULT;
547 	} else {
548 		if (copy_to_user(buffer, ff_up,
549 				 sizeof(struct uinput_ff_upload)))
550 			return -EFAULT;
551 	}
552 
553 	return 0;
554 }
555 
556 static int uinput_ff_upload_from_user(const char __user *buffer,
557 				      struct uinput_ff_upload *ff_up)
558 {
559 	if (INPUT_COMPAT_TEST) {
560 		struct uinput_ff_upload_compat ff_up_compat;
561 
562 		if (copy_from_user(&ff_up_compat, buffer,
563 				   sizeof(struct uinput_ff_upload_compat)))
564 			return -EFAULT;
565 
566 		ff_up->request_id = ff_up_compat.request_id;
567 		ff_up->retval = ff_up_compat.retval;
568 		memcpy(&ff_up->effect, &ff_up_compat.effect,
569 			sizeof(struct ff_effect_compat));
570 		memcpy(&ff_up->old, &ff_up_compat.old,
571 			sizeof(struct ff_effect_compat));
572 
573 	} else {
574 		if (copy_from_user(ff_up, buffer,
575 				   sizeof(struct uinput_ff_upload)))
576 			return -EFAULT;
577 	}
578 
579 	return 0;
580 }
581 
582 #else
583 
584 static int uinput_ff_upload_to_user(char __user *buffer,
585 				    const struct uinput_ff_upload *ff_up)
586 {
587 	if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
588 		return -EFAULT;
589 
590 	return 0;
591 }
592 
593 static int uinput_ff_upload_from_user(const char __user *buffer,
594 				      struct uinput_ff_upload *ff_up)
595 {
596 	if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
597 		return -EFAULT;
598 
599 	return 0;
600 }
601 
602 #endif
603 
604 #define uinput_set_bit(_arg, _bit, _max)		\
605 ({							\
606 	int __ret = 0;					\
607 	if (udev->state == UIST_CREATED)		\
608 		__ret =  -EINVAL;			\
609 	else if ((_arg) > (_max))			\
610 		__ret = -EINVAL;			\
611 	else set_bit((_arg), udev->dev->_bit);		\
612 	__ret;						\
613 })
614 
615 static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
616 				 unsigned long arg, void __user *p)
617 {
618 	int			retval;
619 	struct uinput_device	*udev = file->private_data;
620 	struct uinput_ff_upload ff_up;
621 	struct uinput_ff_erase  ff_erase;
622 	struct uinput_request   *req;
623 	char			*phys;
624 
625 	retval = mutex_lock_interruptible(&udev->mutex);
626 	if (retval)
627 		return retval;
628 
629 	if (!udev->dev) {
630 		retval = uinput_allocate_device(udev);
631 		if (retval)
632 			goto out;
633 	}
634 
635 	switch (cmd) {
636 		case UI_DEV_CREATE:
637 			retval = uinput_create_device(udev);
638 			break;
639 
640 		case UI_DEV_DESTROY:
641 			uinput_destroy_device(udev);
642 			break;
643 
644 		case UI_SET_EVBIT:
645 			retval = uinput_set_bit(arg, evbit, EV_MAX);
646 			break;
647 
648 		case UI_SET_KEYBIT:
649 			retval = uinput_set_bit(arg, keybit, KEY_MAX);
650 			break;
651 
652 		case UI_SET_RELBIT:
653 			retval = uinput_set_bit(arg, relbit, REL_MAX);
654 			break;
655 
656 		case UI_SET_ABSBIT:
657 			retval = uinput_set_bit(arg, absbit, ABS_MAX);
658 			break;
659 
660 		case UI_SET_MSCBIT:
661 			retval = uinput_set_bit(arg, mscbit, MSC_MAX);
662 			break;
663 
664 		case UI_SET_LEDBIT:
665 			retval = uinput_set_bit(arg, ledbit, LED_MAX);
666 			break;
667 
668 		case UI_SET_SNDBIT:
669 			retval = uinput_set_bit(arg, sndbit, SND_MAX);
670 			break;
671 
672 		case UI_SET_FFBIT:
673 			retval = uinput_set_bit(arg, ffbit, FF_MAX);
674 			break;
675 
676 		case UI_SET_SWBIT:
677 			retval = uinput_set_bit(arg, swbit, SW_MAX);
678 			break;
679 
680 		case UI_SET_PROPBIT:
681 			retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
682 			break;
683 
684 		case UI_SET_PHYS:
685 			if (udev->state == UIST_CREATED) {
686 				retval = -EINVAL;
687 				goto out;
688 			}
689 
690 			phys = strndup_user(p, 1024);
691 			if (IS_ERR(phys)) {
692 				retval = PTR_ERR(phys);
693 				goto out;
694 			}
695 
696 			kfree(udev->dev->phys);
697 			udev->dev->phys = phys;
698 			break;
699 
700 		case UI_BEGIN_FF_UPLOAD:
701 			retval = uinput_ff_upload_from_user(p, &ff_up);
702 			if (retval)
703 				break;
704 
705 			req = uinput_request_find(udev, ff_up.request_id);
706 			if (!req || req->code != UI_FF_UPLOAD || !req->u.upload.effect) {
707 				retval = -EINVAL;
708 				break;
709 			}
710 
711 			ff_up.retval = 0;
712 			ff_up.effect = *req->u.upload.effect;
713 			if (req->u.upload.old)
714 				ff_up.old = *req->u.upload.old;
715 			else
716 				memset(&ff_up.old, 0, sizeof(struct ff_effect));
717 
718 			retval = uinput_ff_upload_to_user(p, &ff_up);
719 			break;
720 
721 		case UI_BEGIN_FF_ERASE:
722 			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
723 				retval = -EFAULT;
724 				break;
725 			}
726 
727 			req = uinput_request_find(udev, ff_erase.request_id);
728 			if (!req || req->code != UI_FF_ERASE) {
729 				retval = -EINVAL;
730 				break;
731 			}
732 
733 			ff_erase.retval = 0;
734 			ff_erase.effect_id = req->u.effect_id;
735 			if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
736 				retval = -EFAULT;
737 				break;
738 			}
739 
740 			break;
741 
742 		case UI_END_FF_UPLOAD:
743 			retval = uinput_ff_upload_from_user(p, &ff_up);
744 			if (retval)
745 				break;
746 
747 			req = uinput_request_find(udev, ff_up.request_id);
748 			if (!req || req->code != UI_FF_UPLOAD ||
749 			    !req->u.upload.effect) {
750 				retval = -EINVAL;
751 				break;
752 			}
753 
754 			req->retval = ff_up.retval;
755 			uinput_request_done(udev, req);
756 			break;
757 
758 		case UI_END_FF_ERASE:
759 			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
760 				retval = -EFAULT;
761 				break;
762 			}
763 
764 			req = uinput_request_find(udev, ff_erase.request_id);
765 			if (!req || req->code != UI_FF_ERASE) {
766 				retval = -EINVAL;
767 				break;
768 			}
769 
770 			req->retval = ff_erase.retval;
771 			uinput_request_done(udev, req);
772 			break;
773 
774 		default:
775 			retval = -EINVAL;
776 	}
777 
778  out:
779 	mutex_unlock(&udev->mutex);
780 	return retval;
781 }
782 
783 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
784 {
785 	return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
786 }
787 
788 #ifdef CONFIG_COMPAT
789 static long uinput_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
790 {
791 	return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
792 }
793 #endif
794 
795 static const struct file_operations uinput_fops = {
796 	.owner		= THIS_MODULE,
797 	.open		= uinput_open,
798 	.release	= uinput_release,
799 	.read		= uinput_read,
800 	.write		= uinput_write,
801 	.poll		= uinput_poll,
802 	.unlocked_ioctl	= uinput_ioctl,
803 #ifdef CONFIG_COMPAT
804 	.compat_ioctl	= uinput_compat_ioctl,
805 #endif
806 	.llseek		= no_llseek,
807 };
808 
809 static struct miscdevice uinput_misc = {
810 	.fops		= &uinput_fops,
811 	.minor		= UINPUT_MINOR,
812 	.name		= UINPUT_NAME,
813 };
814 MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
815 MODULE_ALIAS("devname:" UINPUT_NAME);
816 
817 static int __init uinput_init(void)
818 {
819 	return misc_register(&uinput_misc);
820 }
821 
822 static void __exit uinput_exit(void)
823 {
824 	misc_deregister(&uinput_misc);
825 }
826 
827 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
828 MODULE_DESCRIPTION("User level driver support for input subsystem");
829 MODULE_LICENSE("GPL");
830 MODULE_VERSION("0.3");
831 
832 module_init(uinput_init);
833 module_exit(uinput_exit);
834 
835