xref: /linux/drivers/input/misc/uinput.c (revision c053784454550cf750399caa65482b31ffbe3c57)
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 (input_abs_get_max(dev, cnt) <= input_abs_get_min(dev, cnt)) {
308 			printk(KERN_DEBUG
309 				"%s: invalid abs[%02x] min:%d max:%d\n",
310 				UINPUT_NAME, cnt,
311 				input_abs_get_min(dev, cnt),
312 				input_abs_get_max(dev, cnt));
313 			retval = -EINVAL;
314 			break;
315 		}
316 
317 		if (input_abs_get_flat(dev, cnt) >
318 		    input_abs_get_max(dev, cnt) - input_abs_get_min(dev, cnt)) {
319 			printk(KERN_DEBUG
320 				"%s: abs_flat #%02x out of range: %d "
321 				"(min:%d/max:%d)\n",
322 				UINPUT_NAME, cnt,
323 				input_abs_get_flat(dev, cnt),
324 				input_abs_get_min(dev, cnt),
325 				input_abs_get_max(dev, cnt));
326 			retval = -EINVAL;
327 			break;
328 		}
329 	}
330 	return retval;
331 }
332 
333 static int uinput_allocate_device(struct uinput_device *udev)
334 {
335 	udev->dev = input_allocate_device();
336 	if (!udev->dev)
337 		return -ENOMEM;
338 
339 	udev->dev->event = uinput_dev_event;
340 	input_set_drvdata(udev->dev, udev);
341 
342 	return 0;
343 }
344 
345 static int uinput_setup_device(struct uinput_device *udev, const char __user *buffer, size_t count)
346 {
347 	struct uinput_user_dev	*user_dev;
348 	struct input_dev	*dev;
349 	char			*name;
350 	int			i, size;
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 = kmalloc(sizeof(struct uinput_user_dev), GFP_KERNEL);
365 	if (!user_dev)
366 		return -ENOMEM;
367 
368 	if (copy_from_user(user_dev, buffer, sizeof(struct uinput_user_dev))) {
369 		retval = -EFAULT;
370 		goto exit;
371 	}
372 
373 	udev->ff_effects_max = user_dev->ff_effects_max;
374 
375 	size = strnlen(user_dev->name, UINPUT_MAX_NAME_SIZE) + 1;
376 	if (!size) {
377 		retval = -EINVAL;
378 		goto exit;
379 	}
380 
381 	kfree(dev->name);
382 	dev->name = name = kmalloc(size, GFP_KERNEL);
383 	if (!name) {
384 		retval = -ENOMEM;
385 		goto exit;
386 	}
387 	strlcpy(name, user_dev->name, size);
388 
389 	dev->id.bustype	= user_dev->id.bustype;
390 	dev->id.vendor	= user_dev->id.vendor;
391 	dev->id.product	= user_dev->id.product;
392 	dev->id.version	= user_dev->id.version;
393 
394 	for (i = 0; i < ABS_CNT; i++) {
395 		input_abs_set_max(dev, i, user_dev->absmax[i]);
396 		input_abs_set_min(dev, i, user_dev->absmin[i]);
397 		input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
398 		input_abs_set_flat(dev, i, user_dev->absflat[i]);
399 	}
400 
401 	/* check if absmin/absmax/absfuzz/absflat are filled as
402 	 * told in Documentation/input/input-programming.txt */
403 	if (test_bit(EV_ABS, dev->evbit)) {
404 		retval = uinput_validate_absbits(dev);
405 		if (retval < 0)
406 			goto exit;
407 		if (test_bit(ABS_MT_SLOT, dev->absbit)) {
408 			int nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
409 			input_mt_create_slots(dev, nslot);
410 			input_set_events_per_packet(dev, 6 * 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_PHYS:
684 			if (udev->state == UIST_CREATED) {
685 				retval = -EINVAL;
686 				goto out;
687 			}
688 			length = strnlen_user(p, 1024);
689 			if (length <= 0) {
690 				retval = -EFAULT;
691 				break;
692 			}
693 			kfree(udev->dev->phys);
694 			udev->dev->phys = phys = kmalloc(length, GFP_KERNEL);
695 			if (!phys) {
696 				retval = -ENOMEM;
697 				break;
698 			}
699 			if (copy_from_user(phys, p, length)) {
700 				udev->dev->phys = NULL;
701 				kfree(phys);
702 				retval = -EFAULT;
703 				break;
704 			}
705 			phys[length - 1] = '\0';
706 			break;
707 
708 		case UI_BEGIN_FF_UPLOAD:
709 			retval = uinput_ff_upload_from_user(p, &ff_up);
710 			if (retval)
711 				break;
712 
713 			req = uinput_request_find(udev, ff_up.request_id);
714 			if (!req || req->code != UI_FF_UPLOAD || !req->u.upload.effect) {
715 				retval = -EINVAL;
716 				break;
717 			}
718 
719 			ff_up.retval = 0;
720 			ff_up.effect = *req->u.upload.effect;
721 			if (req->u.upload.old)
722 				ff_up.old = *req->u.upload.old;
723 			else
724 				memset(&ff_up.old, 0, sizeof(struct ff_effect));
725 
726 			retval = uinput_ff_upload_to_user(p, &ff_up);
727 			break;
728 
729 		case UI_BEGIN_FF_ERASE:
730 			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
731 				retval = -EFAULT;
732 				break;
733 			}
734 
735 			req = uinput_request_find(udev, ff_erase.request_id);
736 			if (!req || req->code != UI_FF_ERASE) {
737 				retval = -EINVAL;
738 				break;
739 			}
740 
741 			ff_erase.retval = 0;
742 			ff_erase.effect_id = req->u.effect_id;
743 			if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
744 				retval = -EFAULT;
745 				break;
746 			}
747 
748 			break;
749 
750 		case UI_END_FF_UPLOAD:
751 			retval = uinput_ff_upload_from_user(p, &ff_up);
752 			if (retval)
753 				break;
754 
755 			req = uinput_request_find(udev, ff_up.request_id);
756 			if (!req || req->code != UI_FF_UPLOAD ||
757 			    !req->u.upload.effect) {
758 				retval = -EINVAL;
759 				break;
760 			}
761 
762 			req->retval = ff_up.retval;
763 			uinput_request_done(udev, req);
764 			break;
765 
766 		case UI_END_FF_ERASE:
767 			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
768 				retval = -EFAULT;
769 				break;
770 			}
771 
772 			req = uinput_request_find(udev, ff_erase.request_id);
773 			if (!req || req->code != UI_FF_ERASE) {
774 				retval = -EINVAL;
775 				break;
776 			}
777 
778 			req->retval = ff_erase.retval;
779 			uinput_request_done(udev, req);
780 			break;
781 
782 		default:
783 			retval = -EINVAL;
784 	}
785 
786  out:
787 	mutex_unlock(&udev->mutex);
788 	return retval;
789 }
790 
791 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
792 {
793 	return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
794 }
795 
796 #ifdef CONFIG_COMPAT
797 static long uinput_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
798 {
799 	return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
800 }
801 #endif
802 
803 static const struct file_operations uinput_fops = {
804 	.owner		= THIS_MODULE,
805 	.open		= uinput_open,
806 	.release	= uinput_release,
807 	.read		= uinput_read,
808 	.write		= uinput_write,
809 	.poll		= uinput_poll,
810 	.unlocked_ioctl	= uinput_ioctl,
811 #ifdef CONFIG_COMPAT
812 	.compat_ioctl	= uinput_compat_ioctl,
813 #endif
814 	.llseek		= no_llseek,
815 };
816 
817 static struct miscdevice uinput_misc = {
818 	.fops		= &uinput_fops,
819 	.minor		= UINPUT_MINOR,
820 	.name		= UINPUT_NAME,
821 };
822 MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
823 MODULE_ALIAS("devname:" UINPUT_NAME);
824 
825 static int __init uinput_init(void)
826 {
827 	return misc_register(&uinput_misc);
828 }
829 
830 static void __exit uinput_exit(void)
831 {
832 	misc_deregister(&uinput_misc);
833 }
834 
835 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
836 MODULE_DESCRIPTION("User level driver support for input subsystem");
837 MODULE_LICENSE("GPL");
838 MODULE_VERSION("0.3");
839 
840 module_init(uinput_init);
841 module_exit(uinput_exit);
842 
843