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v3.1
  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
 43static 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. */
 59static 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
 79static 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
 88static 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
 95static 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
104static 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 */
133static 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
151static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
152{
153	uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
154}
155
156static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
157{
158	uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
159}
160
161static 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
166static 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
198static 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
221static 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
244static 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
279static 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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
299static 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
338static 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
350static 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
422static 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
437static 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
455static 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
495static 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
507static 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
518struct 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
525static 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
556static 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
584static 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
593static 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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
615static 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
783static 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
789static 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
795static 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
809static struct miscdevice uinput_misc = {
810	.fops		= &uinput_fops,
811	.minor		= UINPUT_MINOR,
812	.name		= UINPUT_NAME,
813};
 
 
814MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
815MODULE_ALIAS("devname:" UINPUT_NAME);
816
817static int __init uinput_init(void)
818{
819	return misc_register(&uinput_misc);
820}
821
822static void __exit uinput_exit(void)
823{
824	misc_deregister(&uinput_misc);
825}
826
827MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
828MODULE_DESCRIPTION("User level driver support for input subsystem");
829MODULE_LICENSE("GPL");
830MODULE_VERSION("0.3");
831
832module_init(uinput_init);
833module_exit(uinput_exit);
834
v4.17
   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 *	0.4	01/09/2014 (Benjamin Tissoires <benjamin.tissoires@redhat.com>)
  24 *		- add UI_GET_SYSNAME ioctl
  25 *	0.3	09/04/2006 (Anssi Hannula <anssi.hannula@gmail.com>)
  26 *		- updated ff support for the changes in kernel interface
  27 *		- added MODULE_VERSION
  28 *	0.2	16/10/2004 (Micah Dowty <micah@navi.cx>)
  29 *		- added force feedback support
  30 *              - added UI_SET_PHYS
  31 *	0.1	20/06/2002
  32 *		- first public version
  33 */
  34#include <uapi/linux/uinput.h>
  35#include <linux/poll.h>
  36#include <linux/sched.h>
  37#include <linux/slab.h>
  38#include <linux/module.h>
  39#include <linux/init.h>
  40#include <linux/fs.h>
  41#include <linux/miscdevice.h>
 
  42#include <linux/input/mt.h>
  43#include "../input-compat.h"
  44
  45#define UINPUT_NAME		"uinput"
  46#define UINPUT_BUFFER_SIZE	16
  47#define UINPUT_NUM_REQUESTS	16
  48
  49enum uinput_state { UIST_NEW_DEVICE, UIST_SETUP_COMPLETE, UIST_CREATED };
  50
  51struct uinput_request {
  52	unsigned int		id;
  53	unsigned int		code;	/* UI_FF_UPLOAD, UI_FF_ERASE */
  54
  55	int			retval;
  56	struct completion	done;
  57
  58	union {
  59		unsigned int	effect_id;
  60		struct {
  61			struct ff_effect *effect;
  62			struct ff_effect *old;
  63		} upload;
  64	} u;
  65};
  66
  67struct uinput_device {
  68	struct input_dev	*dev;
  69	struct mutex		mutex;
  70	enum uinput_state	state;
  71	wait_queue_head_t	waitq;
  72	unsigned char		ready;
  73	unsigned char		head;
  74	unsigned char		tail;
  75	struct input_event	buff[UINPUT_BUFFER_SIZE];
  76	unsigned int		ff_effects_max;
  77
  78	struct uinput_request	*requests[UINPUT_NUM_REQUESTS];
  79	wait_queue_head_t	requests_waitq;
  80	spinlock_t		requests_lock;
  81};
  82
  83static int uinput_dev_event(struct input_dev *dev,
  84			    unsigned int type, unsigned int code, int value)
  85{
  86	struct uinput_device	*udev = input_get_drvdata(dev);
  87	struct timespec64	ts;
  88
  89	udev->buff[udev->head].type = type;
  90	udev->buff[udev->head].code = code;
  91	udev->buff[udev->head].value = value;
  92	ktime_get_ts64(&ts);
  93	udev->buff[udev->head].input_event_sec = ts.tv_sec;
  94	udev->buff[udev->head].input_event_usec = ts.tv_nsec / NSEC_PER_USEC;
  95	udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
  96
  97	wake_up_interruptible(&udev->waitq);
  98
  99	return 0;
 100}
 101
 102/* Atomically allocate an ID for the given request. Returns 0 on success. */
 103static bool uinput_request_alloc_id(struct uinput_device *udev,
 104				    struct uinput_request *request)
 105{
 106	unsigned int id;
 107	bool reserved = false;
 108
 109	spin_lock(&udev->requests_lock);
 110
 111	for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
 112		if (!udev->requests[id]) {
 113			request->id = id;
 114			udev->requests[id] = request;
 115			reserved = true;
 116			break;
 117		}
 118	}
 119
 120	spin_unlock(&udev->requests_lock);
 121	return reserved;
 122}
 123
 124static struct uinput_request *uinput_request_find(struct uinput_device *udev,
 125						  unsigned int id)
 126{
 127	/* Find an input request, by ID. Returns NULL if the ID isn't valid. */
 128	if (id >= UINPUT_NUM_REQUESTS)
 129		return NULL;
 130
 131	return udev->requests[id];
 132}
 133
 134static int uinput_request_reserve_slot(struct uinput_device *udev,
 135				       struct uinput_request *request)
 136{
 137	/* Allocate slot. If none are available right away, wait. */
 138	return wait_event_interruptible(udev->requests_waitq,
 139					uinput_request_alloc_id(udev, request));
 140}
 141
 142static void uinput_request_release_slot(struct uinput_device *udev,
 143					unsigned int id)
 144{
 145	/* Mark slot as available */
 146	spin_lock(&udev->requests_lock);
 147	udev->requests[id] = NULL;
 148	spin_unlock(&udev->requests_lock);
 149
 150	wake_up(&udev->requests_waitq);
 151}
 152
 153static int uinput_request_send(struct uinput_device *udev,
 154			       struct uinput_request *request)
 155{
 156	int retval;
 157
 
 
 
 
 158	retval = mutex_lock_interruptible(&udev->mutex);
 159	if (retval)
 160		return retval;
 161
 162	if (udev->state != UIST_CREATED) {
 163		retval = -ENODEV;
 164		goto out;
 165	}
 166
 167	init_completion(&request->done);
 168
 169	/*
 170	 * Tell our userspace application about this new request
 171	 * by queueing an input event.
 172	 */
 173	uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
 174
 175 out:
 176	mutex_unlock(&udev->mutex);
 177	return retval;
 178}
 179
 180static int uinput_request_submit(struct uinput_device *udev,
 181				 struct uinput_request *request)
 182{
 183	int retval;
 184
 185	retval = uinput_request_reserve_slot(udev, request);
 186	if (retval)
 187		return retval;
 188
 189	retval = uinput_request_send(udev, request);
 190	if (retval)
 191		goto out;
 192
 193	if (!wait_for_completion_timeout(&request->done, 30 * HZ)) {
 194		retval = -ETIMEDOUT;
 195		goto out;
 196	}
 197
 198	retval = request->retval;
 199
 200 out:
 201	uinput_request_release_slot(udev, request->id);
 202	return retval;
 203}
 204
 205/*
 206 * Fail all outstanding requests so handlers don't wait for the userspace
 207 * to finish processing them.
 208 */
 209static void uinput_flush_requests(struct uinput_device *udev)
 210{
 211	struct uinput_request *request;
 212	int i;
 213
 214	spin_lock(&udev->requests_lock);
 215
 216	for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
 217		request = udev->requests[i];
 218		if (request) {
 219			request->retval = -ENODEV;
 220			complete(&request->done);
 221		}
 222	}
 223
 224	spin_unlock(&udev->requests_lock);
 225}
 226
 227static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
 228{
 229	uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
 230}
 231
 232static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
 233{
 234	uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
 235}
 236
 237static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
 238{
 239	return uinput_dev_event(dev, EV_FF, effect_id, value);
 240}
 241
 242static int uinput_dev_upload_effect(struct input_dev *dev,
 243				    struct ff_effect *effect,
 244				    struct ff_effect *old)
 245{
 246	struct uinput_device *udev = input_get_drvdata(dev);
 247	struct uinput_request request;
 
 248
 249	/*
 250	 * uinput driver does not currently support periodic effects with
 251	 * custom waveform since it does not have a way to pass buffer of
 252	 * samples (custom_data) to userspace. If ever there is a device
 253	 * supporting custom waveforms we would need to define an additional
 254	 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
 255	 */
 256	if (effect->type == FF_PERIODIC &&
 257			effect->u.periodic.waveform == FF_CUSTOM)
 258		return -EINVAL;
 259
 
 
 260	request.code = UI_FF_UPLOAD;
 261	request.u.upload.effect = effect;
 262	request.u.upload.old = old;
 263
 264	return uinput_request_submit(udev, &request);
 
 
 
 
 
 
 265}
 266
 267static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
 268{
 269	struct uinput_device *udev = input_get_drvdata(dev);
 270	struct uinput_request request;
 
 271
 272	if (!test_bit(EV_FF, dev->evbit))
 273		return -ENOSYS;
 274
 
 
 275	request.code = UI_FF_ERASE;
 276	request.u.effect_id = effect_id;
 277
 278	return uinput_request_submit(udev, &request);
 279}
 
 
 
 280
 281static int uinput_dev_flush(struct input_dev *dev, struct file *file)
 282{
 283	/*
 284	 * If we are called with file == NULL that means we are tearing
 285	 * down the device, and therefore we can not handle FF erase
 286	 * requests: either we are handling UI_DEV_DESTROY (and holding
 287	 * the udev->mutex), or the file descriptor is closed and there is
 288	 * nobody on the other side anymore.
 289	 */
 290	return file ? input_ff_flush(dev, file) : 0;
 291}
 292
 293static void uinput_destroy_device(struct uinput_device *udev)
 294{
 295	const char *name, *phys;
 296	struct input_dev *dev = udev->dev;
 297	enum uinput_state old_state = udev->state;
 298
 299	udev->state = UIST_NEW_DEVICE;
 300
 301	if (dev) {
 302		name = dev->name;
 303		phys = dev->phys;
 304		if (old_state == UIST_CREATED) {
 305			uinput_flush_requests(udev);
 306			input_unregister_device(dev);
 307		} else {
 308			input_free_device(dev);
 309		}
 310		kfree(name);
 311		kfree(phys);
 312		udev->dev = NULL;
 313	}
 314}
 315
 316static int uinput_create_device(struct uinput_device *udev)
 317{
 318	struct input_dev *dev = udev->dev;
 319	int error, nslot;
 320
 321	if (udev->state != UIST_SETUP_COMPLETE) {
 322		printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
 323		return -EINVAL;
 324	}
 325
 326	if (test_bit(EV_ABS, dev->evbit)) {
 327		input_alloc_absinfo(dev);
 328		if (!dev->absinfo) {
 329			error = -EINVAL;
 330			goto fail1;
 331		}
 332
 333		if (test_bit(ABS_MT_SLOT, dev->absbit)) {
 334			nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
 335			error = input_mt_init_slots(dev, nslot, 0);
 336			if (error)
 337				goto fail1;
 338		} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
 339			input_set_events_per_packet(dev, 60);
 340		}
 341	}
 342
 343	if (test_bit(EV_FF, dev->evbit) && !udev->ff_effects_max) {
 344		printk(KERN_DEBUG "%s: ff_effects_max should be non-zero when FF_BIT is set\n",
 345			UINPUT_NAME);
 346		error = -EINVAL;
 347		goto fail1;
 348	}
 349
 350	if (udev->ff_effects_max) {
 351		error = input_ff_create(dev, udev->ff_effects_max);
 352		if (error)
 353			goto fail1;
 354
 355		dev->ff->upload = uinput_dev_upload_effect;
 356		dev->ff->erase = uinput_dev_erase_effect;
 357		dev->ff->playback = uinput_dev_playback;
 358		dev->ff->set_gain = uinput_dev_set_gain;
 359		dev->ff->set_autocenter = uinput_dev_set_autocenter;
 360		/*
 361		 * The standard input_ff_flush() implementation does
 362		 * not quite work for uinput as we can't reasonably
 363		 * handle FF requests during device teardown.
 364		 */
 365		dev->flush = uinput_dev_flush;
 366	}
 367
 368	dev->event = uinput_dev_event;
 369
 370	input_set_drvdata(udev->dev, udev);
 371
 372	error = input_register_device(udev->dev);
 373	if (error)
 374		goto fail2;
 375
 376	udev->state = UIST_CREATED;
 377
 378	return 0;
 379
 380 fail2:	input_ff_destroy(dev);
 381 fail1: uinput_destroy_device(udev);
 382	return error;
 383}
 384
 385static int uinput_open(struct inode *inode, struct file *file)
 386{
 387	struct uinput_device *newdev;
 388
 389	newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
 390	if (!newdev)
 391		return -ENOMEM;
 392
 393	mutex_init(&newdev->mutex);
 394	spin_lock_init(&newdev->requests_lock);
 395	init_waitqueue_head(&newdev->requests_waitq);
 396	init_waitqueue_head(&newdev->waitq);
 397	newdev->state = UIST_NEW_DEVICE;
 398
 399	file->private_data = newdev;
 400	nonseekable_open(inode, file);
 401
 402	return 0;
 403}
 404
 405static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code,
 406				   const struct input_absinfo *abs)
 407{
 408	int min, max;
 409
 410	min = abs->minimum;
 411	max = abs->maximum;
 412
 413	if ((min != 0 || max != 0) && max <= min) {
 414		printk(KERN_DEBUG
 415		       "%s: invalid abs[%02x] min:%d max:%d\n",
 416		       UINPUT_NAME, code, min, max);
 417		return -EINVAL;
 418	}
 419
 420	if (abs->flat > max - min) {
 421		printk(KERN_DEBUG
 422		       "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n",
 423		       UINPUT_NAME, code, abs->flat, min, max);
 424		return -EINVAL;
 425	}
 426
 427	return 0;
 428}
 429
 430static int uinput_validate_absbits(struct input_dev *dev)
 431{
 432	unsigned int cnt;
 433	int error;
 434
 435	if (!test_bit(EV_ABS, dev->evbit))
 436		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 437
 438	/*
 439	 * Check if absmin/absmax/absfuzz/absflat are sane.
 440	 */
 441
 442	for_each_set_bit(cnt, dev->absbit, ABS_CNT) {
 443		if (!dev->absinfo)
 444			return -EINVAL;
 445
 446		error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]);
 447		if (error)
 448			return error;
 
 449	}
 450
 451	return 0;
 452}
 453
 454static int uinput_dev_setup(struct uinput_device *udev,
 455			    struct uinput_setup __user *arg)
 456{
 457	struct uinput_setup setup;
 458	struct input_dev *dev;
 459
 460	if (udev->state == UIST_CREATED)
 461		return -EINVAL;
 462
 463	if (copy_from_user(&setup, arg, sizeof(setup)))
 464		return -EFAULT;
 465
 466	if (!setup.name[0])
 467		return -EINVAL;
 468
 469	dev = udev->dev;
 470	dev->id = setup.id;
 471	udev->ff_effects_max = setup.ff_effects_max;
 472
 473	kfree(dev->name);
 474	dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL);
 475	if (!dev->name)
 476		return -ENOMEM;
 477
 478	udev->state = UIST_SETUP_COMPLETE;
 479	return 0;
 480}
 481
 482static int uinput_abs_setup(struct uinput_device *udev,
 483			    struct uinput_setup __user *arg, size_t size)
 484{
 485	struct uinput_abs_setup setup = {};
 486	struct input_dev *dev;
 487	int error;
 488
 489	if (size > sizeof(setup))
 490		return -E2BIG;
 491
 492	if (udev->state == UIST_CREATED)
 493		return -EINVAL;
 494
 495	if (copy_from_user(&setup, arg, size))
 496		return -EFAULT;
 497
 498	if (setup.code > ABS_MAX)
 499		return -ERANGE;
 500
 501	dev = udev->dev;
 502
 503	error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo);
 504	if (error)
 505		return error;
 506
 507	input_alloc_absinfo(dev);
 508	if (!dev->absinfo)
 509		return -ENOMEM;
 510
 511	set_bit(setup.code, dev->absbit);
 512	dev->absinfo[setup.code] = setup.absinfo;
 513	return 0;
 514}
 515
 516/* legacy setup via write() */
 517static int uinput_setup_device_legacy(struct uinput_device *udev,
 518				      const char __user *buffer, size_t count)
 519{
 520	struct uinput_user_dev	*user_dev;
 521	struct input_dev	*dev;
 522	int			i;
 523	int			retval;
 524
 525	if (count != sizeof(struct uinput_user_dev))
 526		return -EINVAL;
 527
 528	if (!udev->dev) {
 529		udev->dev = input_allocate_device();
 530		if (!udev->dev)
 531			return -ENOMEM;
 532	}
 533
 534	dev = udev->dev;
 535
 536	user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
 537	if (IS_ERR(user_dev))
 538		return PTR_ERR(user_dev);
 539
 540	udev->ff_effects_max = user_dev->ff_effects_max;
 541
 542	/* Ensure name is filled in */
 543	if (!user_dev->name[0]) {
 544		retval = -EINVAL;
 545		goto exit;
 546	}
 547
 548	kfree(dev->name);
 549	dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
 550			     GFP_KERNEL);
 551	if (!dev->name) {
 552		retval = -ENOMEM;
 553		goto exit;
 554	}
 555
 556	dev->id.bustype	= user_dev->id.bustype;
 557	dev->id.vendor	= user_dev->id.vendor;
 558	dev->id.product	= user_dev->id.product;
 559	dev->id.version	= user_dev->id.version;
 560
 561	for (i = 0; i < ABS_CNT; i++) {
 562		input_abs_set_max(dev, i, user_dev->absmax[i]);
 563		input_abs_set_min(dev, i, user_dev->absmin[i]);
 564		input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
 565		input_abs_set_flat(dev, i, user_dev->absflat[i]);
 566	}
 567
 568	retval = uinput_validate_absbits(dev);
 569	if (retval < 0)
 570		goto exit;
 
 
 
 
 
 
 
 
 
 
 571
 572	udev->state = UIST_SETUP_COMPLETE;
 573	retval = count;
 574
 575 exit:
 576	kfree(user_dev);
 577	return retval;
 578}
 579
 580static ssize_t uinput_inject_events(struct uinput_device *udev,
 581				    const char __user *buffer, size_t count)
 582{
 583	struct input_event ev;
 584	size_t bytes = 0;
 585
 586	if (count != 0 && count < input_event_size())
 587		return -EINVAL;
 588
 589	while (bytes + input_event_size() <= count) {
 590		/*
 591		 * Note that even if some events were fetched successfully
 592		 * we are still going to return EFAULT instead of partial
 593		 * count to let userspace know that it got it's buffers
 594		 * all wrong.
 595		 */
 596		if (input_event_from_user(buffer + bytes, &ev))
 597			return -EFAULT;
 598
 599		input_event(udev->dev, ev.type, ev.code, ev.value);
 600		bytes += input_event_size();
 601	}
 602
 603	return bytes;
 604}
 605
 606static ssize_t uinput_write(struct file *file, const char __user *buffer,
 607			    size_t count, loff_t *ppos)
 608{
 609	struct uinput_device *udev = file->private_data;
 610	int retval;
 611
 612	if (count == 0)
 613		return 0;
 614
 615	retval = mutex_lock_interruptible(&udev->mutex);
 616	if (retval)
 617		return retval;
 618
 619	retval = udev->state == UIST_CREATED ?
 620			uinput_inject_events(udev, buffer, count) :
 621			uinput_setup_device_legacy(udev, buffer, count);
 622
 623	mutex_unlock(&udev->mutex);
 624
 625	return retval;
 626}
 627
 628static bool uinput_fetch_next_event(struct uinput_device *udev,
 629				    struct input_event *event)
 630{
 631	bool have_event;
 
 632
 633	spin_lock_irq(&udev->dev->event_lock);
 
 634
 635	have_event = udev->head != udev->tail;
 636	if (have_event) {
 637		*event = udev->buff[udev->tail];
 638		udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
 639	}
 640
 641	spin_unlock_irq(&udev->dev->event_lock);
 
 
 
 642
 643	return have_event;
 644}
 
 645
 646static ssize_t uinput_events_to_user(struct uinput_device *udev,
 647				     char __user *buffer, size_t count)
 648{
 649	struct input_event event;
 650	size_t read = 0;
 651
 652	while (read + input_event_size() <= count &&
 653	       uinput_fetch_next_event(udev, &event)) {
 654
 655		if (input_event_to_user(buffer + read, &event))
 656			return -EFAULT;
 657
 658		read += input_event_size();
 659	}
 660
 661	return read;
 662}
 663
 664static ssize_t uinput_read(struct file *file, char __user *buffer,
 665			   size_t count, loff_t *ppos)
 666{
 667	struct uinput_device *udev = file->private_data;
 668	ssize_t retval;
 669
 670	if (count != 0 && count < input_event_size())
 671		return -EINVAL;
 672
 673	do {
 674		retval = mutex_lock_interruptible(&udev->mutex);
 675		if (retval)
 676			return retval;
 677
 678		if (udev->state != UIST_CREATED)
 679			retval = -ENODEV;
 680		else if (udev->head == udev->tail &&
 681			 (file->f_flags & O_NONBLOCK))
 682			retval = -EAGAIN;
 683		else
 684			retval = uinput_events_to_user(udev, buffer, count);
 685
 686		mutex_unlock(&udev->mutex);
 687
 688		if (retval || count == 0)
 689			break;
 690
 691		if (!(file->f_flags & O_NONBLOCK))
 692			retval = wait_event_interruptible(udev->waitq,
 693						  udev->head != udev->tail ||
 694						  udev->state != UIST_CREATED);
 695	} while (retval == 0);
 696
 697	return retval;
 698}
 699
 700static __poll_t uinput_poll(struct file *file, poll_table *wait)
 701{
 702	struct uinput_device *udev = file->private_data;
 703
 704	poll_wait(file, &udev->waitq, wait);
 705
 706	if (udev->head != udev->tail)
 707		return EPOLLIN | EPOLLRDNORM;
 708
 709	return 0;
 710}
 711
 712static int uinput_release(struct inode *inode, struct file *file)
 713{
 714	struct uinput_device *udev = file->private_data;
 715
 716	uinput_destroy_device(udev);
 717	kfree(udev);
 718
 719	return 0;
 720}
 721
 722#ifdef CONFIG_COMPAT
 723struct uinput_ff_upload_compat {
 724	__u32			request_id;
 725	__s32			retval;
 726	struct ff_effect_compat	effect;
 727	struct ff_effect_compat	old;
 728};
 729
 730static int uinput_ff_upload_to_user(char __user *buffer,
 731				    const struct uinput_ff_upload *ff_up)
 732{
 733	if (in_compat_syscall()) {
 734		struct uinput_ff_upload_compat ff_up_compat;
 735
 736		ff_up_compat.request_id = ff_up->request_id;
 737		ff_up_compat.retval = ff_up->retval;
 738		/*
 739		 * It so happens that the pointer that gives us the trouble
 740		 * is the last field in the structure. Since we don't support
 741		 * custom waveforms in uinput anyway we can just copy the whole
 742		 * thing (to the compat size) and ignore the pointer.
 743		 */
 744		memcpy(&ff_up_compat.effect, &ff_up->effect,
 745			sizeof(struct ff_effect_compat));
 746		memcpy(&ff_up_compat.old, &ff_up->old,
 747			sizeof(struct ff_effect_compat));
 748
 749		if (copy_to_user(buffer, &ff_up_compat,
 750				 sizeof(struct uinput_ff_upload_compat)))
 751			return -EFAULT;
 752	} else {
 753		if (copy_to_user(buffer, ff_up,
 754				 sizeof(struct uinput_ff_upload)))
 755			return -EFAULT;
 756	}
 757
 758	return 0;
 759}
 760
 761static int uinput_ff_upload_from_user(const char __user *buffer,
 762				      struct uinput_ff_upload *ff_up)
 763{
 764	if (in_compat_syscall()) {
 765		struct uinput_ff_upload_compat ff_up_compat;
 766
 767		if (copy_from_user(&ff_up_compat, buffer,
 768				   sizeof(struct uinput_ff_upload_compat)))
 769			return -EFAULT;
 770
 771		ff_up->request_id = ff_up_compat.request_id;
 772		ff_up->retval = ff_up_compat.retval;
 773		memcpy(&ff_up->effect, &ff_up_compat.effect,
 774			sizeof(struct ff_effect_compat));
 775		memcpy(&ff_up->old, &ff_up_compat.old,
 776			sizeof(struct ff_effect_compat));
 777
 778	} else {
 779		if (copy_from_user(ff_up, buffer,
 780				   sizeof(struct uinput_ff_upload)))
 781			return -EFAULT;
 782	}
 783
 784	return 0;
 785}
 786
 787#else
 788
 789static int uinput_ff_upload_to_user(char __user *buffer,
 790				    const struct uinput_ff_upload *ff_up)
 791{
 792	if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
 793		return -EFAULT;
 794
 795	return 0;
 796}
 797
 798static int uinput_ff_upload_from_user(const char __user *buffer,
 799				      struct uinput_ff_upload *ff_up)
 800{
 801	if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
 802		return -EFAULT;
 803
 804	return 0;
 805}
 806
 807#endif
 808
 809#define uinput_set_bit(_arg, _bit, _max)		\
 810({							\
 811	int __ret = 0;					\
 812	if (udev->state == UIST_CREATED)		\
 813		__ret =  -EINVAL;			\
 814	else if ((_arg) > (_max))			\
 815		__ret = -EINVAL;			\
 816	else set_bit((_arg), udev->dev->_bit);		\
 817	__ret;						\
 818})
 819
 820static int uinput_str_to_user(void __user *dest, const char *str,
 821			      unsigned int maxlen)
 822{
 823	char __user *p = dest;
 824	int len, ret;
 825
 826	if (!str)
 827		return -ENOENT;
 828
 829	if (maxlen == 0)
 830		return -EINVAL;
 831
 832	len = strlen(str) + 1;
 833	if (len > maxlen)
 834		len = maxlen;
 835
 836	ret = copy_to_user(p, str, len);
 837	if (ret)
 838		return -EFAULT;
 839
 840	/* force terminating '\0' */
 841	ret = put_user(0, p + len - 1);
 842	return ret ? -EFAULT : len;
 843}
 844
 845static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
 846				 unsigned long arg, void __user *p)
 847{
 848	int			retval;
 849	struct uinput_device	*udev = file->private_data;
 850	struct uinput_ff_upload ff_up;
 851	struct uinput_ff_erase  ff_erase;
 852	struct uinput_request   *req;
 853	char			*phys;
 854	const char		*name;
 855	unsigned int		size;
 856
 857	retval = mutex_lock_interruptible(&udev->mutex);
 858	if (retval)
 859		return retval;
 860
 861	if (!udev->dev) {
 862		udev->dev = input_allocate_device();
 863		if (!udev->dev) {
 864			retval = -ENOMEM;
 865			goto out;
 866		}
 867	}
 868
 869	switch (cmd) {
 870	case UI_GET_VERSION:
 871		if (put_user(UINPUT_VERSION, (unsigned int __user *)p))
 872			retval = -EFAULT;
 873		goto out;
 874
 875	case UI_DEV_CREATE:
 876		retval = uinput_create_device(udev);
 877		goto out;
 878
 879	case UI_DEV_DESTROY:
 880		uinput_destroy_device(udev);
 881		goto out;
 882
 883	case UI_DEV_SETUP:
 884		retval = uinput_dev_setup(udev, p);
 885		goto out;
 886
 887	/* UI_ABS_SETUP is handled in the variable size ioctls */
 
 
 888
 889	case UI_SET_EVBIT:
 890		retval = uinput_set_bit(arg, evbit, EV_MAX);
 891		goto out;
 892
 893	case UI_SET_KEYBIT:
 894		retval = uinput_set_bit(arg, keybit, KEY_MAX);
 895		goto out;
 896
 897	case UI_SET_RELBIT:
 898		retval = uinput_set_bit(arg, relbit, REL_MAX);
 899		goto out;
 900
 901	case UI_SET_ABSBIT:
 902		retval = uinput_set_bit(arg, absbit, ABS_MAX);
 903		goto out;
 904
 905	case UI_SET_MSCBIT:
 906		retval = uinput_set_bit(arg, mscbit, MSC_MAX);
 907		goto out;
 908
 909	case UI_SET_LEDBIT:
 910		retval = uinput_set_bit(arg, ledbit, LED_MAX);
 911		goto out;
 912
 913	case UI_SET_SNDBIT:
 914		retval = uinput_set_bit(arg, sndbit, SND_MAX);
 915		goto out;
 916
 917	case UI_SET_FFBIT:
 918		retval = uinput_set_bit(arg, ffbit, FF_MAX);
 919		goto out;
 
 
 
 
 
 
 
 
 920
 921	case UI_SET_SWBIT:
 922		retval = uinput_set_bit(arg, swbit, SW_MAX);
 923		goto out;
 924
 925	case UI_SET_PROPBIT:
 926		retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
 927		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 928
 929	case UI_SET_PHYS:
 930		if (udev->state == UIST_CREATED) {
 931			retval = -EINVAL;
 932			goto out;
 933		}
 934
 935		phys = strndup_user(p, 1024);
 936		if (IS_ERR(phys)) {
 937			retval = PTR_ERR(phys);
 938			goto out;
 939		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 940
 941		kfree(udev->dev->phys);
 942		udev->dev->phys = phys;
 943		goto out;
 944
 945	case UI_BEGIN_FF_UPLOAD:
 946		retval = uinput_ff_upload_from_user(p, &ff_up);
 947		if (retval)
 948			goto out;
 
 
 
 
 
 
 
 949
 950		req = uinput_request_find(udev, ff_up.request_id);
 951		if (!req || req->code != UI_FF_UPLOAD ||
 952		    !req->u.upload.effect) {
 953			retval = -EINVAL;
 954			goto out;
 955		}
 956
 957		ff_up.retval = 0;
 958		ff_up.effect = *req->u.upload.effect;
 959		if (req->u.upload.old)
 960			ff_up.old = *req->u.upload.old;
 961		else
 962			memset(&ff_up.old, 0, sizeof(struct ff_effect));
 
 
 
 
 
 963
 964		retval = uinput_ff_upload_to_user(p, &ff_up);
 965		goto out;
 966
 967	case UI_BEGIN_FF_ERASE:
 968		if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
 969			retval = -EFAULT;
 970			goto out;
 971		}
 972
 973		req = uinput_request_find(udev, ff_erase.request_id);
 974		if (!req || req->code != UI_FF_ERASE) {
 975			retval = -EINVAL;
 976			goto out;
 977		}
 978
 979		ff_erase.retval = 0;
 980		ff_erase.effect_id = req->u.effect_id;
 981		if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
 982			retval = -EFAULT;
 983			goto out;
 984		}
 985
 986		goto out;
 987
 988	case UI_END_FF_UPLOAD:
 989		retval = uinput_ff_upload_from_user(p, &ff_up);
 990		if (retval)
 991			goto out;
 992
 993		req = uinput_request_find(udev, ff_up.request_id);
 994		if (!req || req->code != UI_FF_UPLOAD ||
 995		    !req->u.upload.effect) {
 996			retval = -EINVAL;
 997			goto out;
 998		}
 999
1000		req->retval = ff_up.retval;
1001		complete(&req->done);
1002		goto out;
1003
1004	case UI_END_FF_ERASE:
1005		if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
1006			retval = -EFAULT;
1007			goto out;
1008		}
1009
1010		req = uinput_request_find(udev, ff_erase.request_id);
1011		if (!req || req->code != UI_FF_ERASE) {
1012			retval = -EINVAL;
1013			goto out;
1014		}
1015
1016		req->retval = ff_erase.retval;
1017		complete(&req->done);
1018		goto out;
1019	}
1020
1021	size = _IOC_SIZE(cmd);
1022
1023	/* Now check variable-length commands */
1024	switch (cmd & ~IOCSIZE_MASK) {
1025	case UI_GET_SYSNAME(0):
1026		if (udev->state != UIST_CREATED) {
1027			retval = -ENOENT;
1028			goto out;
1029		}
1030		name = dev_name(&udev->dev->dev);
1031		retval = uinput_str_to_user(p, name, size);
1032		goto out;
1033
1034	case UI_ABS_SETUP & ~IOCSIZE_MASK:
1035		retval = uinput_abs_setup(udev, p, size);
1036		goto out;
1037	}
1038
1039	retval = -EINVAL;
1040 out:
1041	mutex_unlock(&udev->mutex);
1042	return retval;
1043}
1044
1045static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1046{
1047	return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
1048}
1049
1050#ifdef CONFIG_COMPAT
1051
1052#define UI_SET_PHYS_COMPAT	_IOW(UINPUT_IOCTL_BASE, 108, compat_uptr_t)
1053
1054static long uinput_compat_ioctl(struct file *file,
1055				unsigned int cmd, unsigned long arg)
1056{
1057	if (cmd == UI_SET_PHYS_COMPAT)
1058		cmd = UI_SET_PHYS;
1059
1060	return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
1061}
1062#endif
1063
1064static const struct file_operations uinput_fops = {
1065	.owner		= THIS_MODULE,
1066	.open		= uinput_open,
1067	.release	= uinput_release,
1068	.read		= uinput_read,
1069	.write		= uinput_write,
1070	.poll		= uinput_poll,
1071	.unlocked_ioctl	= uinput_ioctl,
1072#ifdef CONFIG_COMPAT
1073	.compat_ioctl	= uinput_compat_ioctl,
1074#endif
1075	.llseek		= no_llseek,
1076};
1077
1078static struct miscdevice uinput_misc = {
1079	.fops		= &uinput_fops,
1080	.minor		= UINPUT_MINOR,
1081	.name		= UINPUT_NAME,
1082};
1083module_misc_device(uinput_misc);
1084
1085MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
1086MODULE_ALIAS("devname:" UINPUT_NAME);
1087
 
 
 
 
 
 
 
 
 
 
1088MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
1089MODULE_DESCRIPTION("User level driver support for input subsystem");
1090MODULE_LICENSE("GPL");