xref: /openbmc/linux/drivers/input/misc/uinput.c (revision 930beb5a)
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,
44 			    unsigned int type, unsigned int code, int value)
45 {
46 	struct uinput_device	*udev = input_get_drvdata(dev);
47 
48 	udev->buff[udev->head].type = type;
49 	udev->buff[udev->head].code = code;
50 	udev->buff[udev->head].value = value;
51 	do_gettimeofday(&udev->buff[udev->head].time);
52 	udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
53 
54 	wake_up_interruptible(&udev->waitq);
55 
56 	return 0;
57 }
58 
59 /* Atomically allocate an ID for the given request. Returns 0 on success. */
60 static bool uinput_request_alloc_id(struct uinput_device *udev,
61 				    struct uinput_request *request)
62 {
63 	unsigned int id;
64 	bool reserved = false;
65 
66 	spin_lock(&udev->requests_lock);
67 
68 	for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
69 		if (!udev->requests[id]) {
70 			request->id = id;
71 			udev->requests[id] = request;
72 			reserved = true;
73 			break;
74 		}
75 	}
76 
77 	spin_unlock(&udev->requests_lock);
78 	return reserved;
79 }
80 
81 static struct uinput_request *uinput_request_find(struct uinput_device *udev,
82 						  unsigned int id)
83 {
84 	/* Find an input request, by ID. Returns NULL if the ID isn't valid. */
85 	if (id >= UINPUT_NUM_REQUESTS)
86 		return NULL;
87 
88 	return udev->requests[id];
89 }
90 
91 static int uinput_request_reserve_slot(struct uinput_device *udev,
92 				       struct uinput_request *request)
93 {
94 	/* Allocate slot. If none are available right away, wait. */
95 	return wait_event_interruptible(udev->requests_waitq,
96 					uinput_request_alloc_id(udev, request));
97 }
98 
99 static void uinput_request_done(struct uinput_device *udev,
100 				struct uinput_request *request)
101 {
102 	/* Mark slot as available */
103 	udev->requests[request->id] = NULL;
104 	wake_up(&udev->requests_waitq);
105 
106 	complete(&request->done);
107 }
108 
109 static int uinput_request_send(struct uinput_device *udev,
110 			       struct uinput_request *request)
111 {
112 	int retval;
113 
114 	retval = mutex_lock_interruptible(&udev->mutex);
115 	if (retval)
116 		return retval;
117 
118 	if (udev->state != UIST_CREATED) {
119 		retval = -ENODEV;
120 		goto out;
121 	}
122 
123 	init_completion(&request->done);
124 
125 	/*
126 	 * Tell our userspace application about this new request
127 	 * by queueing an input event.
128 	 */
129 	uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
130 
131  out:
132 	mutex_unlock(&udev->mutex);
133 	return retval;
134 }
135 
136 static int uinput_request_submit(struct uinput_device *udev,
137 				 struct uinput_request *request)
138 {
139 	int error;
140 
141 	error = uinput_request_reserve_slot(udev, request);
142 	if (error)
143 		return error;
144 
145 	error = uinput_request_send(udev, request);
146 	if (error) {
147 		uinput_request_done(udev, request);
148 		return error;
149 	}
150 
151 	wait_for_completion(&request->done);
152 	return request->retval;
153 }
154 
155 /*
156  * Fail all outstanding requests so handlers don't wait for the userspace
157  * to finish processing them.
158  */
159 static void uinput_flush_requests(struct uinput_device *udev)
160 {
161 	struct uinput_request *request;
162 	int i;
163 
164 	spin_lock(&udev->requests_lock);
165 
166 	for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
167 		request = udev->requests[i];
168 		if (request) {
169 			request->retval = -ENODEV;
170 			uinput_request_done(udev, request);
171 		}
172 	}
173 
174 	spin_unlock(&udev->requests_lock);
175 }
176 
177 static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
178 {
179 	uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
180 }
181 
182 static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
183 {
184 	uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
185 }
186 
187 static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
188 {
189 	return uinput_dev_event(dev, EV_FF, effect_id, value);
190 }
191 
192 static int uinput_dev_upload_effect(struct input_dev *dev,
193 				    struct ff_effect *effect,
194 				    struct ff_effect *old)
195 {
196 	struct uinput_device *udev = input_get_drvdata(dev);
197 	struct uinput_request request;
198 
199 	/*
200 	 * uinput driver does not currently support periodic effects with
201 	 * custom waveform since it does not have a way to pass buffer of
202 	 * samples (custom_data) to userspace. If ever there is a device
203 	 * supporting custom waveforms we would need to define an additional
204 	 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
205 	 */
206 	if (effect->type == FF_PERIODIC &&
207 			effect->u.periodic.waveform == FF_CUSTOM)
208 		return -EINVAL;
209 
210 	request.code = UI_FF_UPLOAD;
211 	request.u.upload.effect = effect;
212 	request.u.upload.old = old;
213 
214 	return uinput_request_submit(udev, &request);
215 }
216 
217 static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
218 {
219 	struct uinput_device *udev = input_get_drvdata(dev);
220 	struct uinput_request request;
221 
222 	if (!test_bit(EV_FF, dev->evbit))
223 		return -ENOSYS;
224 
225 	request.code = UI_FF_ERASE;
226 	request.u.effect_id = effect_id;
227 
228 	return uinput_request_submit(udev, &request);
229 }
230 
231 static void uinput_destroy_device(struct uinput_device *udev)
232 {
233 	const char *name, *phys;
234 	struct input_dev *dev = udev->dev;
235 	enum uinput_state old_state = udev->state;
236 
237 	udev->state = UIST_NEW_DEVICE;
238 
239 	if (dev) {
240 		name = dev->name;
241 		phys = dev->phys;
242 		if (old_state == UIST_CREATED) {
243 			uinput_flush_requests(udev);
244 			input_unregister_device(dev);
245 		} else {
246 			input_free_device(dev);
247 		}
248 		kfree(name);
249 		kfree(phys);
250 		udev->dev = NULL;
251 	}
252 }
253 
254 static int uinput_create_device(struct uinput_device *udev)
255 {
256 	struct input_dev *dev = udev->dev;
257 	int error;
258 
259 	if (udev->state != UIST_SETUP_COMPLETE) {
260 		printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
261 		return -EINVAL;
262 	}
263 
264 	if (udev->ff_effects_max) {
265 		error = input_ff_create(dev, udev->ff_effects_max);
266 		if (error)
267 			goto fail1;
268 
269 		dev->ff->upload = uinput_dev_upload_effect;
270 		dev->ff->erase = uinput_dev_erase_effect;
271 		dev->ff->playback = uinput_dev_playback;
272 		dev->ff->set_gain = uinput_dev_set_gain;
273 		dev->ff->set_autocenter = uinput_dev_set_autocenter;
274 	}
275 
276 	error = input_register_device(udev->dev);
277 	if (error)
278 		goto fail2;
279 
280 	udev->state = UIST_CREATED;
281 
282 	return 0;
283 
284  fail2:	input_ff_destroy(dev);
285  fail1: uinput_destroy_device(udev);
286 	return error;
287 }
288 
289 static int uinput_open(struct inode *inode, struct file *file)
290 {
291 	struct uinput_device *newdev;
292 
293 	newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
294 	if (!newdev)
295 		return -ENOMEM;
296 
297 	mutex_init(&newdev->mutex);
298 	spin_lock_init(&newdev->requests_lock);
299 	init_waitqueue_head(&newdev->requests_waitq);
300 	init_waitqueue_head(&newdev->waitq);
301 	newdev->state = UIST_NEW_DEVICE;
302 
303 	file->private_data = newdev;
304 	nonseekable_open(inode, file);
305 
306 	return 0;
307 }
308 
309 static int uinput_validate_absbits(struct input_dev *dev)
310 {
311 	unsigned int cnt;
312 	int retval = 0;
313 
314 	for (cnt = 0; cnt < ABS_CNT; cnt++) {
315 		int min, max;
316 		if (!test_bit(cnt, dev->absbit))
317 			continue;
318 
319 		min = input_abs_get_min(dev, cnt);
320 		max = input_abs_get_max(dev, cnt);
321 
322 		if ((min != 0 || max != 0) && max <= min) {
323 			printk(KERN_DEBUG
324 				"%s: invalid abs[%02x] min:%d max:%d\n",
325 				UINPUT_NAME, cnt,
326 				input_abs_get_min(dev, cnt),
327 				input_abs_get_max(dev, cnt));
328 			retval = -EINVAL;
329 			break;
330 		}
331 
332 		if (input_abs_get_flat(dev, cnt) >
333 		    input_abs_get_max(dev, cnt) - input_abs_get_min(dev, cnt)) {
334 			printk(KERN_DEBUG
335 				"%s: abs_flat #%02x out of range: %d "
336 				"(min:%d/max:%d)\n",
337 				UINPUT_NAME, cnt,
338 				input_abs_get_flat(dev, cnt),
339 				input_abs_get_min(dev, cnt),
340 				input_abs_get_max(dev, cnt));
341 			retval = -EINVAL;
342 			break;
343 		}
344 	}
345 	return retval;
346 }
347 
348 static int uinput_allocate_device(struct uinput_device *udev)
349 {
350 	udev->dev = input_allocate_device();
351 	if (!udev->dev)
352 		return -ENOMEM;
353 
354 	udev->dev->event = uinput_dev_event;
355 	input_set_drvdata(udev->dev, udev);
356 
357 	return 0;
358 }
359 
360 static int uinput_setup_device(struct uinput_device *udev,
361 			       const char __user *buffer, size_t count)
362 {
363 	struct uinput_user_dev	*user_dev;
364 	struct input_dev	*dev;
365 	int			i;
366 	int			retval;
367 
368 	if (count != sizeof(struct uinput_user_dev))
369 		return -EINVAL;
370 
371 	if (!udev->dev) {
372 		retval = uinput_allocate_device(udev);
373 		if (retval)
374 			return retval;
375 	}
376 
377 	dev = udev->dev;
378 
379 	user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
380 	if (IS_ERR(user_dev))
381 		return PTR_ERR(user_dev);
382 
383 	udev->ff_effects_max = user_dev->ff_effects_max;
384 
385 	/* Ensure name is filled in */
386 	if (!user_dev->name[0]) {
387 		retval = -EINVAL;
388 		goto exit;
389 	}
390 
391 	kfree(dev->name);
392 	dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
393 			     GFP_KERNEL);
394 	if (!dev->name) {
395 		retval = -ENOMEM;
396 		goto exit;
397 	}
398 
399 	dev->id.bustype	= user_dev->id.bustype;
400 	dev->id.vendor	= user_dev->id.vendor;
401 	dev->id.product	= user_dev->id.product;
402 	dev->id.version	= user_dev->id.version;
403 
404 	for (i = 0; i < ABS_CNT; i++) {
405 		input_abs_set_max(dev, i, user_dev->absmax[i]);
406 		input_abs_set_min(dev, i, user_dev->absmin[i]);
407 		input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
408 		input_abs_set_flat(dev, i, user_dev->absflat[i]);
409 	}
410 
411 	/* check if absmin/absmax/absfuzz/absflat are filled as
412 	 * told in Documentation/input/input-programming.txt */
413 	if (test_bit(EV_ABS, dev->evbit)) {
414 		retval = uinput_validate_absbits(dev);
415 		if (retval < 0)
416 			goto exit;
417 		if (test_bit(ABS_MT_SLOT, dev->absbit)) {
418 			int nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
419 			input_mt_init_slots(dev, nslot, 0);
420 		} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
421 			input_set_events_per_packet(dev, 60);
422 		}
423 	}
424 
425 	udev->state = UIST_SETUP_COMPLETE;
426 	retval = count;
427 
428  exit:
429 	kfree(user_dev);
430 	return retval;
431 }
432 
433 static ssize_t uinput_inject_events(struct uinput_device *udev,
434 				    const char __user *buffer, size_t count)
435 {
436 	struct input_event ev;
437 	size_t bytes = 0;
438 
439 	if (count != 0 && count < input_event_size())
440 		return -EINVAL;
441 
442 	while (bytes + input_event_size() <= count) {
443 		/*
444 		 * Note that even if some events were fetched successfully
445 		 * we are still going to return EFAULT instead of partial
446 		 * count to let userspace know that it got it's buffers
447 		 * all wrong.
448 		 */
449 		if (input_event_from_user(buffer + bytes, &ev))
450 			return -EFAULT;
451 
452 		input_event(udev->dev, ev.type, ev.code, ev.value);
453 		bytes += input_event_size();
454 	}
455 
456 	return bytes;
457 }
458 
459 static ssize_t uinput_write(struct file *file, const char __user *buffer,
460 			    size_t count, loff_t *ppos)
461 {
462 	struct uinput_device *udev = file->private_data;
463 	int retval;
464 
465 	if (count == 0)
466 		return 0;
467 
468 	retval = mutex_lock_interruptible(&udev->mutex);
469 	if (retval)
470 		return retval;
471 
472 	retval = udev->state == UIST_CREATED ?
473 			uinput_inject_events(udev, buffer, count) :
474 			uinput_setup_device(udev, buffer, count);
475 
476 	mutex_unlock(&udev->mutex);
477 
478 	return retval;
479 }
480 
481 static bool uinput_fetch_next_event(struct uinput_device *udev,
482 				    struct input_event *event)
483 {
484 	bool have_event;
485 
486 	spin_lock_irq(&udev->dev->event_lock);
487 
488 	have_event = udev->head != udev->tail;
489 	if (have_event) {
490 		*event = udev->buff[udev->tail];
491 		udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
492 	}
493 
494 	spin_unlock_irq(&udev->dev->event_lock);
495 
496 	return have_event;
497 }
498 
499 static ssize_t uinput_events_to_user(struct uinput_device *udev,
500 				     char __user *buffer, size_t count)
501 {
502 	struct input_event event;
503 	size_t read = 0;
504 
505 	while (read + input_event_size() <= count &&
506 	       uinput_fetch_next_event(udev, &event)) {
507 
508 		if (input_event_to_user(buffer + read, &event))
509 			return -EFAULT;
510 
511 		read += input_event_size();
512 	}
513 
514 	return read;
515 }
516 
517 static ssize_t uinput_read(struct file *file, char __user *buffer,
518 			   size_t count, loff_t *ppos)
519 {
520 	struct uinput_device *udev = file->private_data;
521 	ssize_t retval;
522 
523 	if (count != 0 && count < input_event_size())
524 		return -EINVAL;
525 
526 	do {
527 		retval = mutex_lock_interruptible(&udev->mutex);
528 		if (retval)
529 			return retval;
530 
531 		if (udev->state != UIST_CREATED)
532 			retval = -ENODEV;
533 		else if (udev->head == udev->tail &&
534 			 (file->f_flags & O_NONBLOCK))
535 			retval = -EAGAIN;
536 		else
537 			retval = uinput_events_to_user(udev, buffer, count);
538 
539 		mutex_unlock(&udev->mutex);
540 
541 		if (retval || count == 0)
542 			break;
543 
544 		if (!(file->f_flags & O_NONBLOCK))
545 			retval = wait_event_interruptible(udev->waitq,
546 						  udev->head != udev->tail ||
547 						  udev->state != UIST_CREATED);
548 	} while (retval == 0);
549 
550 	return retval;
551 }
552 
553 static unsigned int uinput_poll(struct file *file, poll_table *wait)
554 {
555 	struct uinput_device *udev = file->private_data;
556 
557 	poll_wait(file, &udev->waitq, wait);
558 
559 	if (udev->head != udev->tail)
560 		return POLLIN | POLLRDNORM;
561 
562 	return 0;
563 }
564 
565 static int uinput_release(struct inode *inode, struct file *file)
566 {
567 	struct uinput_device *udev = file->private_data;
568 
569 	uinput_destroy_device(udev);
570 	kfree(udev);
571 
572 	return 0;
573 }
574 
575 #ifdef CONFIG_COMPAT
576 struct uinput_ff_upload_compat {
577 	__u32			request_id;
578 	__s32			retval;
579 	struct ff_effect_compat	effect;
580 	struct ff_effect_compat	old;
581 };
582 
583 static int uinput_ff_upload_to_user(char __user *buffer,
584 				    const struct uinput_ff_upload *ff_up)
585 {
586 	if (INPUT_COMPAT_TEST) {
587 		struct uinput_ff_upload_compat ff_up_compat;
588 
589 		ff_up_compat.request_id = ff_up->request_id;
590 		ff_up_compat.retval = ff_up->retval;
591 		/*
592 		 * It so happens that the pointer that gives us the trouble
593 		 * is the last field in the structure. Since we don't support
594 		 * custom waveforms in uinput anyway we can just copy the whole
595 		 * thing (to the compat size) and ignore the pointer.
596 		 */
597 		memcpy(&ff_up_compat.effect, &ff_up->effect,
598 			sizeof(struct ff_effect_compat));
599 		memcpy(&ff_up_compat.old, &ff_up->old,
600 			sizeof(struct ff_effect_compat));
601 
602 		if (copy_to_user(buffer, &ff_up_compat,
603 				 sizeof(struct uinput_ff_upload_compat)))
604 			return -EFAULT;
605 	} else {
606 		if (copy_to_user(buffer, ff_up,
607 				 sizeof(struct uinput_ff_upload)))
608 			return -EFAULT;
609 	}
610 
611 	return 0;
612 }
613 
614 static int uinput_ff_upload_from_user(const char __user *buffer,
615 				      struct uinput_ff_upload *ff_up)
616 {
617 	if (INPUT_COMPAT_TEST) {
618 		struct uinput_ff_upload_compat ff_up_compat;
619 
620 		if (copy_from_user(&ff_up_compat, buffer,
621 				   sizeof(struct uinput_ff_upload_compat)))
622 			return -EFAULT;
623 
624 		ff_up->request_id = ff_up_compat.request_id;
625 		ff_up->retval = ff_up_compat.retval;
626 		memcpy(&ff_up->effect, &ff_up_compat.effect,
627 			sizeof(struct ff_effect_compat));
628 		memcpy(&ff_up->old, &ff_up_compat.old,
629 			sizeof(struct ff_effect_compat));
630 
631 	} else {
632 		if (copy_from_user(ff_up, buffer,
633 				   sizeof(struct uinput_ff_upload)))
634 			return -EFAULT;
635 	}
636 
637 	return 0;
638 }
639 
640 #else
641 
642 static int uinput_ff_upload_to_user(char __user *buffer,
643 				    const struct uinput_ff_upload *ff_up)
644 {
645 	if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
646 		return -EFAULT;
647 
648 	return 0;
649 }
650 
651 static int uinput_ff_upload_from_user(const char __user *buffer,
652 				      struct uinput_ff_upload *ff_up)
653 {
654 	if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
655 		return -EFAULT;
656 
657 	return 0;
658 }
659 
660 #endif
661 
662 #define uinput_set_bit(_arg, _bit, _max)		\
663 ({							\
664 	int __ret = 0;					\
665 	if (udev->state == UIST_CREATED)		\
666 		__ret =  -EINVAL;			\
667 	else if ((_arg) > (_max))			\
668 		__ret = -EINVAL;			\
669 	else set_bit((_arg), udev->dev->_bit);		\
670 	__ret;						\
671 })
672 
673 static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
674 				 unsigned long arg, void __user *p)
675 {
676 	int			retval;
677 	struct uinput_device	*udev = file->private_data;
678 	struct uinput_ff_upload ff_up;
679 	struct uinput_ff_erase  ff_erase;
680 	struct uinput_request   *req;
681 	char			*phys;
682 
683 	retval = mutex_lock_interruptible(&udev->mutex);
684 	if (retval)
685 		return retval;
686 
687 	if (!udev->dev) {
688 		retval = uinput_allocate_device(udev);
689 		if (retval)
690 			goto out;
691 	}
692 
693 	switch (cmd) {
694 		case UI_DEV_CREATE:
695 			retval = uinput_create_device(udev);
696 			break;
697 
698 		case UI_DEV_DESTROY:
699 			uinput_destroy_device(udev);
700 			break;
701 
702 		case UI_SET_EVBIT:
703 			retval = uinput_set_bit(arg, evbit, EV_MAX);
704 			break;
705 
706 		case UI_SET_KEYBIT:
707 			retval = uinput_set_bit(arg, keybit, KEY_MAX);
708 			break;
709 
710 		case UI_SET_RELBIT:
711 			retval = uinput_set_bit(arg, relbit, REL_MAX);
712 			break;
713 
714 		case UI_SET_ABSBIT:
715 			retval = uinput_set_bit(arg, absbit, ABS_MAX);
716 			break;
717 
718 		case UI_SET_MSCBIT:
719 			retval = uinput_set_bit(arg, mscbit, MSC_MAX);
720 			break;
721 
722 		case UI_SET_LEDBIT:
723 			retval = uinput_set_bit(arg, ledbit, LED_MAX);
724 			break;
725 
726 		case UI_SET_SNDBIT:
727 			retval = uinput_set_bit(arg, sndbit, SND_MAX);
728 			break;
729 
730 		case UI_SET_FFBIT:
731 			retval = uinput_set_bit(arg, ffbit, FF_MAX);
732 			break;
733 
734 		case UI_SET_SWBIT:
735 			retval = uinput_set_bit(arg, swbit, SW_MAX);
736 			break;
737 
738 		case UI_SET_PROPBIT:
739 			retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
740 			break;
741 
742 		case UI_SET_PHYS:
743 			if (udev->state == UIST_CREATED) {
744 				retval = -EINVAL;
745 				goto out;
746 			}
747 
748 			phys = strndup_user(p, 1024);
749 			if (IS_ERR(phys)) {
750 				retval = PTR_ERR(phys);
751 				goto out;
752 			}
753 
754 			kfree(udev->dev->phys);
755 			udev->dev->phys = phys;
756 			break;
757 
758 		case UI_BEGIN_FF_UPLOAD:
759 			retval = uinput_ff_upload_from_user(p, &ff_up);
760 			if (retval)
761 				break;
762 
763 			req = uinput_request_find(udev, ff_up.request_id);
764 			if (!req || req->code != UI_FF_UPLOAD ||
765 			    !req->u.upload.effect) {
766 				retval = -EINVAL;
767 				break;
768 			}
769 
770 			ff_up.retval = 0;
771 			ff_up.effect = *req->u.upload.effect;
772 			if (req->u.upload.old)
773 				ff_up.old = *req->u.upload.old;
774 			else
775 				memset(&ff_up.old, 0, sizeof(struct ff_effect));
776 
777 			retval = uinput_ff_upload_to_user(p, &ff_up);
778 			break;
779 
780 		case UI_BEGIN_FF_ERASE:
781 			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
782 				retval = -EFAULT;
783 				break;
784 			}
785 
786 			req = uinput_request_find(udev, ff_erase.request_id);
787 			if (!req || req->code != UI_FF_ERASE) {
788 				retval = -EINVAL;
789 				break;
790 			}
791 
792 			ff_erase.retval = 0;
793 			ff_erase.effect_id = req->u.effect_id;
794 			if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
795 				retval = -EFAULT;
796 				break;
797 			}
798 
799 			break;
800 
801 		case UI_END_FF_UPLOAD:
802 			retval = uinput_ff_upload_from_user(p, &ff_up);
803 			if (retval)
804 				break;
805 
806 			req = uinput_request_find(udev, ff_up.request_id);
807 			if (!req || req->code != UI_FF_UPLOAD ||
808 			    !req->u.upload.effect) {
809 				retval = -EINVAL;
810 				break;
811 			}
812 
813 			req->retval = ff_up.retval;
814 			uinput_request_done(udev, req);
815 			break;
816 
817 		case UI_END_FF_ERASE:
818 			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
819 				retval = -EFAULT;
820 				break;
821 			}
822 
823 			req = uinput_request_find(udev, ff_erase.request_id);
824 			if (!req || req->code != UI_FF_ERASE) {
825 				retval = -EINVAL;
826 				break;
827 			}
828 
829 			req->retval = ff_erase.retval;
830 			uinput_request_done(udev, req);
831 			break;
832 
833 		default:
834 			retval = -EINVAL;
835 	}
836 
837  out:
838 	mutex_unlock(&udev->mutex);
839 	return retval;
840 }
841 
842 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
843 {
844 	return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
845 }
846 
847 #ifdef CONFIG_COMPAT
848 static long uinput_compat_ioctl(struct file *file,
849 				unsigned int cmd, unsigned long arg)
850 {
851 	return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
852 }
853 #endif
854 
855 static const struct file_operations uinput_fops = {
856 	.owner		= THIS_MODULE,
857 	.open		= uinput_open,
858 	.release	= uinput_release,
859 	.read		= uinput_read,
860 	.write		= uinput_write,
861 	.poll		= uinput_poll,
862 	.unlocked_ioctl	= uinput_ioctl,
863 #ifdef CONFIG_COMPAT
864 	.compat_ioctl	= uinput_compat_ioctl,
865 #endif
866 	.llseek		= no_llseek,
867 };
868 
869 static struct miscdevice uinput_misc = {
870 	.fops		= &uinput_fops,
871 	.minor		= UINPUT_MINOR,
872 	.name		= UINPUT_NAME,
873 };
874 MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
875 MODULE_ALIAS("devname:" UINPUT_NAME);
876 
877 static int __init uinput_init(void)
878 {
879 	return misc_register(&uinput_misc);
880 }
881 
882 static void __exit uinput_exit(void)
883 {
884 	misc_deregister(&uinput_misc);
885 }
886 
887 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
888 MODULE_DESCRIPTION("User level driver support for input subsystem");
889 MODULE_LICENSE("GPL");
890 MODULE_VERSION("0.3");
891 
892 module_init(uinput_init);
893 module_exit(uinput_exit);
894