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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
v5.4
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  User level driver support for input subsystem
   4 *
   5 * Heavily based on evdev.c by Vojtech Pavlik
   6 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   7 * Author: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
   8 *
   9 * Changes/Revisions:
  10 *	0.4	01/09/2014 (Benjamin Tissoires <benjamin.tissoires@redhat.com>)
  11 *		- add UI_GET_SYSNAME ioctl
  12 *	0.3	09/04/2006 (Anssi Hannula <anssi.hannula@gmail.com>)
  13 *		- updated ff support for the changes in kernel interface
  14 *		- added MODULE_VERSION
  15 *	0.2	16/10/2004 (Micah Dowty <micah@navi.cx>)
  16 *		- added force feedback support
  17 *              - added UI_SET_PHYS
  18 *	0.1	20/06/2002
  19 *		- first public version
  20 */
  21#include <uapi/linux/uinput.h>
  22#include <linux/poll.h>
  23#include <linux/sched.h>
  24#include <linux/slab.h>
  25#include <linux/module.h>
  26#include <linux/init.h>
  27#include <linux/fs.h>
  28#include <linux/miscdevice.h>
  29#include <linux/overflow.h>
  30#include <linux/input/mt.h>
  31#include "../input-compat.h"
  32
  33#define UINPUT_NAME		"uinput"
  34#define UINPUT_BUFFER_SIZE	16
  35#define UINPUT_NUM_REQUESTS	16
  36
  37enum uinput_state { UIST_NEW_DEVICE, UIST_SETUP_COMPLETE, UIST_CREATED };
  38
  39struct uinput_request {
  40	unsigned int		id;
  41	unsigned int		code;	/* UI_FF_UPLOAD, UI_FF_ERASE */
  42
  43	int			retval;
  44	struct completion	done;
  45
  46	union {
  47		unsigned int	effect_id;
  48		struct {
  49			struct ff_effect *effect;
  50			struct ff_effect *old;
  51		} upload;
  52	} u;
  53};
  54
  55struct uinput_device {
  56	struct input_dev	*dev;
  57	struct mutex		mutex;
  58	enum uinput_state	state;
  59	wait_queue_head_t	waitq;
  60	unsigned char		ready;
  61	unsigned char		head;
  62	unsigned char		tail;
  63	struct input_event	buff[UINPUT_BUFFER_SIZE];
  64	unsigned int		ff_effects_max;
  65
  66	struct uinput_request	*requests[UINPUT_NUM_REQUESTS];
  67	wait_queue_head_t	requests_waitq;
  68	spinlock_t		requests_lock;
  69};
  70
  71static int uinput_dev_event(struct input_dev *dev,
  72			    unsigned int type, unsigned int code, int value)
  73{
  74	struct uinput_device	*udev = input_get_drvdata(dev);
  75	struct timespec64	ts;
  76
  77	udev->buff[udev->head].type = type;
  78	udev->buff[udev->head].code = code;
  79	udev->buff[udev->head].value = value;
  80	ktime_get_ts64(&ts);
  81	udev->buff[udev->head].input_event_sec = ts.tv_sec;
  82	udev->buff[udev->head].input_event_usec = ts.tv_nsec / NSEC_PER_USEC;
  83	udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
  84
  85	wake_up_interruptible(&udev->waitq);
  86
  87	return 0;
  88}
  89
  90/* Atomically allocate an ID for the given request. Returns 0 on success. */
  91static bool uinput_request_alloc_id(struct uinput_device *udev,
  92				    struct uinput_request *request)
  93{
  94	unsigned int id;
  95	bool reserved = false;
  96
  97	spin_lock(&udev->requests_lock);
  98
  99	for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
 100		if (!udev->requests[id]) {
 101			request->id = id;
 102			udev->requests[id] = request;
 103			reserved = true;
 104			break;
 105		}
 106	}
 107
 108	spin_unlock(&udev->requests_lock);
 109	return reserved;
 110}
 111
 112static struct uinput_request *uinput_request_find(struct uinput_device *udev,
 113						  unsigned int id)
 114{
 115	/* Find an input request, by ID. Returns NULL if the ID isn't valid. */
 116	if (id >= UINPUT_NUM_REQUESTS)
 117		return NULL;
 118
 119	return udev->requests[id];
 120}
 121
 122static int uinput_request_reserve_slot(struct uinput_device *udev,
 123				       struct uinput_request *request)
 124{
 125	/* Allocate slot. If none are available right away, wait. */
 126	return wait_event_interruptible(udev->requests_waitq,
 127					uinput_request_alloc_id(udev, request));
 128}
 129
 130static void uinput_request_release_slot(struct uinput_device *udev,
 131					unsigned int id)
 132{
 133	/* Mark slot as available */
 134	spin_lock(&udev->requests_lock);
 135	udev->requests[id] = NULL;
 136	spin_unlock(&udev->requests_lock);
 137
 138	wake_up(&udev->requests_waitq);
 139}
 140
 141static int uinput_request_send(struct uinput_device *udev,
 142			       struct uinput_request *request)
 143{
 144	int retval;
 145
 
 
 
 
 146	retval = mutex_lock_interruptible(&udev->mutex);
 147	if (retval)
 148		return retval;
 149
 150	if (udev->state != UIST_CREATED) {
 151		retval = -ENODEV;
 152		goto out;
 153	}
 154
 155	init_completion(&request->done);
 156
 157	/*
 158	 * Tell our userspace application about this new request
 159	 * by queueing an input event.
 160	 */
 161	uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
 162
 163 out:
 164	mutex_unlock(&udev->mutex);
 165	return retval;
 166}
 167
 168static int uinput_request_submit(struct uinput_device *udev,
 169				 struct uinput_request *request)
 170{
 171	int retval;
 172
 173	retval = uinput_request_reserve_slot(udev, request);
 174	if (retval)
 175		return retval;
 176
 177	retval = uinput_request_send(udev, request);
 178	if (retval)
 179		goto out;
 180
 181	if (!wait_for_completion_timeout(&request->done, 30 * HZ)) {
 182		retval = -ETIMEDOUT;
 183		goto out;
 184	}
 185
 186	retval = request->retval;
 187
 188 out:
 189	uinput_request_release_slot(udev, request->id);
 190	return retval;
 191}
 192
 193/*
 194 * Fail all outstanding requests so handlers don't wait for the userspace
 195 * to finish processing them.
 196 */
 197static void uinput_flush_requests(struct uinput_device *udev)
 198{
 199	struct uinput_request *request;
 200	int i;
 201
 202	spin_lock(&udev->requests_lock);
 203
 204	for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
 205		request = udev->requests[i];
 206		if (request) {
 207			request->retval = -ENODEV;
 208			complete(&request->done);
 209		}
 210	}
 211
 212	spin_unlock(&udev->requests_lock);
 213}
 214
 215static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
 216{
 217	uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
 218}
 219
 220static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
 221{
 222	uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
 223}
 224
 225static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
 226{
 227	return uinput_dev_event(dev, EV_FF, effect_id, value);
 228}
 229
 230static int uinput_dev_upload_effect(struct input_dev *dev,
 231				    struct ff_effect *effect,
 232				    struct ff_effect *old)
 233{
 234	struct uinput_device *udev = input_get_drvdata(dev);
 235	struct uinput_request request;
 
 236
 237	/*
 238	 * uinput driver does not currently support periodic effects with
 239	 * custom waveform since it does not have a way to pass buffer of
 240	 * samples (custom_data) to userspace. If ever there is a device
 241	 * supporting custom waveforms we would need to define an additional
 242	 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
 243	 */
 244	if (effect->type == FF_PERIODIC &&
 245			effect->u.periodic.waveform == FF_CUSTOM)
 246		return -EINVAL;
 247
 
 
 248	request.code = UI_FF_UPLOAD;
 249	request.u.upload.effect = effect;
 250	request.u.upload.old = old;
 251
 252	return uinput_request_submit(udev, &request);
 
 
 
 
 
 
 253}
 254
 255static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
 256{
 257	struct uinput_device *udev = input_get_drvdata(dev);
 258	struct uinput_request request;
 
 259
 260	if (!test_bit(EV_FF, dev->evbit))
 261		return -ENOSYS;
 262
 
 
 263	request.code = UI_FF_ERASE;
 264	request.u.effect_id = effect_id;
 265
 266	return uinput_request_submit(udev, &request);
 267}
 
 
 
 268
 269static int uinput_dev_flush(struct input_dev *dev, struct file *file)
 270{
 271	/*
 272	 * If we are called with file == NULL that means we are tearing
 273	 * down the device, and therefore we can not handle FF erase
 274	 * requests: either we are handling UI_DEV_DESTROY (and holding
 275	 * the udev->mutex), or the file descriptor is closed and there is
 276	 * nobody on the other side anymore.
 277	 */
 278	return file ? input_ff_flush(dev, file) : 0;
 279}
 280
 281static void uinput_destroy_device(struct uinput_device *udev)
 282{
 283	const char *name, *phys;
 284	struct input_dev *dev = udev->dev;
 285	enum uinput_state old_state = udev->state;
 286
 287	udev->state = UIST_NEW_DEVICE;
 288
 289	if (dev) {
 290		name = dev->name;
 291		phys = dev->phys;
 292		if (old_state == UIST_CREATED) {
 293			uinput_flush_requests(udev);
 294			input_unregister_device(dev);
 295		} else {
 296			input_free_device(dev);
 297		}
 298		kfree(name);
 299		kfree(phys);
 300		udev->dev = NULL;
 301	}
 302}
 303
 304static int uinput_create_device(struct uinput_device *udev)
 305{
 306	struct input_dev *dev = udev->dev;
 307	int error, nslot;
 308
 309	if (udev->state != UIST_SETUP_COMPLETE) {
 310		printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
 311		return -EINVAL;
 312	}
 313
 314	if (test_bit(EV_ABS, dev->evbit)) {
 315		input_alloc_absinfo(dev);
 316		if (!dev->absinfo) {
 317			error = -EINVAL;
 318			goto fail1;
 319		}
 320
 321		if (test_bit(ABS_MT_SLOT, dev->absbit)) {
 322			nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
 323			error = input_mt_init_slots(dev, nslot, 0);
 324			if (error)
 325				goto fail1;
 326		} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
 327			input_set_events_per_packet(dev, 60);
 328		}
 329	}
 330
 331	if (test_bit(EV_FF, dev->evbit) && !udev->ff_effects_max) {
 332		printk(KERN_DEBUG "%s: ff_effects_max should be non-zero when FF_BIT is set\n",
 333			UINPUT_NAME);
 334		error = -EINVAL;
 335		goto fail1;
 336	}
 337
 338	if (udev->ff_effects_max) {
 339		error = input_ff_create(dev, udev->ff_effects_max);
 340		if (error)
 341			goto fail1;
 342
 343		dev->ff->upload = uinput_dev_upload_effect;
 344		dev->ff->erase = uinput_dev_erase_effect;
 345		dev->ff->playback = uinput_dev_playback;
 346		dev->ff->set_gain = uinput_dev_set_gain;
 347		dev->ff->set_autocenter = uinput_dev_set_autocenter;
 348		/*
 349		 * The standard input_ff_flush() implementation does
 350		 * not quite work for uinput as we can't reasonably
 351		 * handle FF requests during device teardown.
 352		 */
 353		dev->flush = uinput_dev_flush;
 354	}
 355
 356	dev->event = uinput_dev_event;
 357
 358	input_set_drvdata(udev->dev, udev);
 359
 360	error = input_register_device(udev->dev);
 361	if (error)
 362		goto fail2;
 363
 364	udev->state = UIST_CREATED;
 365
 366	return 0;
 367
 368 fail2:	input_ff_destroy(dev);
 369 fail1: uinput_destroy_device(udev);
 370	return error;
 371}
 372
 373static int uinput_open(struct inode *inode, struct file *file)
 374{
 375	struct uinput_device *newdev;
 376
 377	newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
 378	if (!newdev)
 379		return -ENOMEM;
 380
 381	mutex_init(&newdev->mutex);
 382	spin_lock_init(&newdev->requests_lock);
 383	init_waitqueue_head(&newdev->requests_waitq);
 384	init_waitqueue_head(&newdev->waitq);
 385	newdev->state = UIST_NEW_DEVICE;
 386
 387	file->private_data = newdev;
 388	stream_open(inode, file);
 389
 390	return 0;
 391}
 392
 393static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code,
 394				   const struct input_absinfo *abs)
 395{
 396	int min, max, range;
 397
 398	min = abs->minimum;
 399	max = abs->maximum;
 400
 401	if ((min != 0 || max != 0) && max < min) {
 402		printk(KERN_DEBUG
 403		       "%s: invalid abs[%02x] min:%d max:%d\n",
 404		       UINPUT_NAME, code, min, max);
 405		return -EINVAL;
 406	}
 407
 408	if (!check_sub_overflow(max, min, &range) && abs->flat > range) {
 409		printk(KERN_DEBUG
 410		       "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n",
 411		       UINPUT_NAME, code, abs->flat, min, max);
 412		return -EINVAL;
 413	}
 414
 415	return 0;
 416}
 417
 418static int uinput_validate_absbits(struct input_dev *dev)
 419{
 420	unsigned int cnt;
 421	int error;
 422
 423	if (!test_bit(EV_ABS, dev->evbit))
 424		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 425
 426	/*
 427	 * Check if absmin/absmax/absfuzz/absflat are sane.
 428	 */
 429
 430	for_each_set_bit(cnt, dev->absbit, ABS_CNT) {
 431		if (!dev->absinfo)
 432			return -EINVAL;
 433
 434		error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]);
 435		if (error)
 436			return error;
 
 437	}
 438
 439	return 0;
 440}
 441
 442static int uinput_dev_setup(struct uinput_device *udev,
 443			    struct uinput_setup __user *arg)
 444{
 445	struct uinput_setup setup;
 446	struct input_dev *dev;
 447
 448	if (udev->state == UIST_CREATED)
 449		return -EINVAL;
 450
 451	if (copy_from_user(&setup, arg, sizeof(setup)))
 452		return -EFAULT;
 453
 454	if (!setup.name[0])
 455		return -EINVAL;
 456
 457	dev = udev->dev;
 458	dev->id = setup.id;
 459	udev->ff_effects_max = setup.ff_effects_max;
 460
 461	kfree(dev->name);
 462	dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL);
 463	if (!dev->name)
 464		return -ENOMEM;
 465
 466	udev->state = UIST_SETUP_COMPLETE;
 467	return 0;
 468}
 469
 470static int uinput_abs_setup(struct uinput_device *udev,
 471			    struct uinput_setup __user *arg, size_t size)
 472{
 473	struct uinput_abs_setup setup = {};
 474	struct input_dev *dev;
 475	int error;
 476
 477	if (size > sizeof(setup))
 478		return -E2BIG;
 479
 480	if (udev->state == UIST_CREATED)
 481		return -EINVAL;
 482
 483	if (copy_from_user(&setup, arg, size))
 484		return -EFAULT;
 485
 486	if (setup.code > ABS_MAX)
 487		return -ERANGE;
 488
 489	dev = udev->dev;
 490
 491	error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo);
 492	if (error)
 493		return error;
 494
 495	input_alloc_absinfo(dev);
 496	if (!dev->absinfo)
 497		return -ENOMEM;
 498
 499	set_bit(setup.code, dev->absbit);
 500	dev->absinfo[setup.code] = setup.absinfo;
 501	return 0;
 502}
 503
 504/* legacy setup via write() */
 505static int uinput_setup_device_legacy(struct uinput_device *udev,
 506				      const char __user *buffer, size_t count)
 507{
 508	struct uinput_user_dev	*user_dev;
 509	struct input_dev	*dev;
 510	int			i;
 511	int			retval;
 512
 513	if (count != sizeof(struct uinput_user_dev))
 514		return -EINVAL;
 515
 516	if (!udev->dev) {
 517		udev->dev = input_allocate_device();
 518		if (!udev->dev)
 519			return -ENOMEM;
 520	}
 521
 522	dev = udev->dev;
 523
 524	user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
 525	if (IS_ERR(user_dev))
 526		return PTR_ERR(user_dev);
 527
 528	udev->ff_effects_max = user_dev->ff_effects_max;
 529
 530	/* Ensure name is filled in */
 531	if (!user_dev->name[0]) {
 532		retval = -EINVAL;
 533		goto exit;
 534	}
 535
 536	kfree(dev->name);
 537	dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
 538			     GFP_KERNEL);
 539	if (!dev->name) {
 540		retval = -ENOMEM;
 541		goto exit;
 542	}
 543
 544	dev->id.bustype	= user_dev->id.bustype;
 545	dev->id.vendor	= user_dev->id.vendor;
 546	dev->id.product	= user_dev->id.product;
 547	dev->id.version	= user_dev->id.version;
 548
 549	for (i = 0; i < ABS_CNT; i++) {
 550		input_abs_set_max(dev, i, user_dev->absmax[i]);
 551		input_abs_set_min(dev, i, user_dev->absmin[i]);
 552		input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
 553		input_abs_set_flat(dev, i, user_dev->absflat[i]);
 554	}
 555
 556	retval = uinput_validate_absbits(dev);
 557	if (retval < 0)
 558		goto exit;
 
 
 
 
 
 
 
 
 
 
 559
 560	udev->state = UIST_SETUP_COMPLETE;
 561	retval = count;
 562
 563 exit:
 564	kfree(user_dev);
 565	return retval;
 566}
 567
 568static ssize_t uinput_inject_events(struct uinput_device *udev,
 569				    const char __user *buffer, size_t count)
 570{
 571	struct input_event ev;
 572	size_t bytes = 0;
 573
 574	if (count != 0 && count < input_event_size())
 575		return -EINVAL;
 576
 577	while (bytes + input_event_size() <= count) {
 578		/*
 579		 * Note that even if some events were fetched successfully
 580		 * we are still going to return EFAULT instead of partial
 581		 * count to let userspace know that it got it's buffers
 582		 * all wrong.
 583		 */
 584		if (input_event_from_user(buffer + bytes, &ev))
 585			return -EFAULT;
 586
 587		input_event(udev->dev, ev.type, ev.code, ev.value);
 588		bytes += input_event_size();
 589		cond_resched();
 590	}
 591
 592	return bytes;
 593}
 594
 595static ssize_t uinput_write(struct file *file, const char __user *buffer,
 596			    size_t count, loff_t *ppos)
 597{
 598	struct uinput_device *udev = file->private_data;
 599	int retval;
 600
 601	if (count == 0)
 602		return 0;
 603
 604	retval = mutex_lock_interruptible(&udev->mutex);
 605	if (retval)
 606		return retval;
 607
 608	retval = udev->state == UIST_CREATED ?
 609			uinput_inject_events(udev, buffer, count) :
 610			uinput_setup_device_legacy(udev, buffer, count);
 611
 612	mutex_unlock(&udev->mutex);
 613
 614	return retval;
 615}
 616
 617static bool uinput_fetch_next_event(struct uinput_device *udev,
 618				    struct input_event *event)
 619{
 620	bool have_event;
 
 621
 622	spin_lock_irq(&udev->dev->event_lock);
 
 623
 624	have_event = udev->head != udev->tail;
 625	if (have_event) {
 626		*event = udev->buff[udev->tail];
 627		udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
 628	}
 629
 630	spin_unlock_irq(&udev->dev->event_lock);
 
 
 
 631
 632	return have_event;
 633}
 
 634
 635static ssize_t uinput_events_to_user(struct uinput_device *udev,
 636				     char __user *buffer, size_t count)
 637{
 638	struct input_event event;
 639	size_t read = 0;
 640
 641	while (read + input_event_size() <= count &&
 642	       uinput_fetch_next_event(udev, &event)) {
 643
 644		if (input_event_to_user(buffer + read, &event))
 645			return -EFAULT;
 646
 647		read += input_event_size();
 648	}
 649
 650	return read;
 651}
 652
 653static ssize_t uinput_read(struct file *file, char __user *buffer,
 654			   size_t count, loff_t *ppos)
 655{
 656	struct uinput_device *udev = file->private_data;
 657	ssize_t retval;
 658
 659	if (count != 0 && count < input_event_size())
 660		return -EINVAL;
 661
 662	do {
 663		retval = mutex_lock_interruptible(&udev->mutex);
 664		if (retval)
 665			return retval;
 666
 667		if (udev->state != UIST_CREATED)
 668			retval = -ENODEV;
 669		else if (udev->head == udev->tail &&
 670			 (file->f_flags & O_NONBLOCK))
 671			retval = -EAGAIN;
 672		else
 673			retval = uinput_events_to_user(udev, buffer, count);
 674
 675		mutex_unlock(&udev->mutex);
 676
 677		if (retval || count == 0)
 678			break;
 679
 680		if (!(file->f_flags & O_NONBLOCK))
 681			retval = wait_event_interruptible(udev->waitq,
 682						  udev->head != udev->tail ||
 683						  udev->state != UIST_CREATED);
 684	} while (retval == 0);
 685
 686	return retval;
 687}
 688
 689static __poll_t uinput_poll(struct file *file, poll_table *wait)
 690{
 691	struct uinput_device *udev = file->private_data;
 692
 693	poll_wait(file, &udev->waitq, wait);
 694
 695	if (udev->head != udev->tail)
 696		return EPOLLIN | EPOLLRDNORM;
 697
 698	return 0;
 699}
 700
 701static int uinput_release(struct inode *inode, struct file *file)
 702{
 703	struct uinput_device *udev = file->private_data;
 704
 705	uinput_destroy_device(udev);
 706	kfree(udev);
 707
 708	return 0;
 709}
 710
 711#ifdef CONFIG_COMPAT
 712struct uinput_ff_upload_compat {
 713	__u32			request_id;
 714	__s32			retval;
 715	struct ff_effect_compat	effect;
 716	struct ff_effect_compat	old;
 717};
 718
 719static int uinput_ff_upload_to_user(char __user *buffer,
 720				    const struct uinput_ff_upload *ff_up)
 721{
 722	if (in_compat_syscall()) {
 723		struct uinput_ff_upload_compat ff_up_compat;
 724
 725		ff_up_compat.request_id = ff_up->request_id;
 726		ff_up_compat.retval = ff_up->retval;
 727		/*
 728		 * It so happens that the pointer that gives us the trouble
 729		 * is the last field in the structure. Since we don't support
 730		 * custom waveforms in uinput anyway we can just copy the whole
 731		 * thing (to the compat size) and ignore the pointer.
 732		 */
 733		memcpy(&ff_up_compat.effect, &ff_up->effect,
 734			sizeof(struct ff_effect_compat));
 735		memcpy(&ff_up_compat.old, &ff_up->old,
 736			sizeof(struct ff_effect_compat));
 737
 738		if (copy_to_user(buffer, &ff_up_compat,
 739				 sizeof(struct uinput_ff_upload_compat)))
 740			return -EFAULT;
 741	} else {
 742		if (copy_to_user(buffer, ff_up,
 743				 sizeof(struct uinput_ff_upload)))
 744			return -EFAULT;
 745	}
 746
 747	return 0;
 748}
 749
 750static int uinput_ff_upload_from_user(const char __user *buffer,
 751				      struct uinput_ff_upload *ff_up)
 752{
 753	if (in_compat_syscall()) {
 754		struct uinput_ff_upload_compat ff_up_compat;
 755
 756		if (copy_from_user(&ff_up_compat, buffer,
 757				   sizeof(struct uinput_ff_upload_compat)))
 758			return -EFAULT;
 759
 760		ff_up->request_id = ff_up_compat.request_id;
 761		ff_up->retval = ff_up_compat.retval;
 762		memcpy(&ff_up->effect, &ff_up_compat.effect,
 763			sizeof(struct ff_effect_compat));
 764		memcpy(&ff_up->old, &ff_up_compat.old,
 765			sizeof(struct ff_effect_compat));
 766
 767	} else {
 768		if (copy_from_user(ff_up, buffer,
 769				   sizeof(struct uinput_ff_upload)))
 770			return -EFAULT;
 771	}
 772
 773	return 0;
 774}
 775
 776#else
 777
 778static int uinput_ff_upload_to_user(char __user *buffer,
 779				    const struct uinput_ff_upload *ff_up)
 780{
 781	if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
 782		return -EFAULT;
 783
 784	return 0;
 785}
 786
 787static int uinput_ff_upload_from_user(const char __user *buffer,
 788				      struct uinput_ff_upload *ff_up)
 789{
 790	if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
 791		return -EFAULT;
 792
 793	return 0;
 794}
 795
 796#endif
 797
 798#define uinput_set_bit(_arg, _bit, _max)		\
 799({							\
 800	int __ret = 0;					\
 801	if (udev->state == UIST_CREATED)		\
 802		__ret =  -EINVAL;			\
 803	else if ((_arg) > (_max))			\
 804		__ret = -EINVAL;			\
 805	else set_bit((_arg), udev->dev->_bit);		\
 806	__ret;						\
 807})
 808
 809static int uinput_str_to_user(void __user *dest, const char *str,
 810			      unsigned int maxlen)
 811{
 812	char __user *p = dest;
 813	int len, ret;
 814
 815	if (!str)
 816		return -ENOENT;
 817
 818	if (maxlen == 0)
 819		return -EINVAL;
 820
 821	len = strlen(str) + 1;
 822	if (len > maxlen)
 823		len = maxlen;
 824
 825	ret = copy_to_user(p, str, len);
 826	if (ret)
 827		return -EFAULT;
 828
 829	/* force terminating '\0' */
 830	ret = put_user(0, p + len - 1);
 831	return ret ? -EFAULT : len;
 832}
 833
 834static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
 835				 unsigned long arg, void __user *p)
 836{
 837	int			retval;
 838	struct uinput_device	*udev = file->private_data;
 839	struct uinput_ff_upload ff_up;
 840	struct uinput_ff_erase  ff_erase;
 841	struct uinput_request   *req;
 842	char			*phys;
 843	const char		*name;
 844	unsigned int		size;
 845
 846	retval = mutex_lock_interruptible(&udev->mutex);
 847	if (retval)
 848		return retval;
 849
 850	if (!udev->dev) {
 851		udev->dev = input_allocate_device();
 852		if (!udev->dev) {
 853			retval = -ENOMEM;
 854			goto out;
 855		}
 856	}
 857
 858	switch (cmd) {
 859	case UI_GET_VERSION:
 860		if (put_user(UINPUT_VERSION, (unsigned int __user *)p))
 861			retval = -EFAULT;
 862		goto out;
 863
 864	case UI_DEV_CREATE:
 865		retval = uinput_create_device(udev);
 866		goto out;
 867
 868	case UI_DEV_DESTROY:
 869		uinput_destroy_device(udev);
 870		goto out;
 871
 872	case UI_DEV_SETUP:
 873		retval = uinput_dev_setup(udev, p);
 874		goto out;
 875
 876	/* UI_ABS_SETUP is handled in the variable size ioctls */
 
 
 877
 878	case UI_SET_EVBIT:
 879		retval = uinput_set_bit(arg, evbit, EV_MAX);
 880		goto out;
 881
 882	case UI_SET_KEYBIT:
 883		retval = uinput_set_bit(arg, keybit, KEY_MAX);
 884		goto out;
 885
 886	case UI_SET_RELBIT:
 887		retval = uinput_set_bit(arg, relbit, REL_MAX);
 888		goto out;
 889
 890	case UI_SET_ABSBIT:
 891		retval = uinput_set_bit(arg, absbit, ABS_MAX);
 892		goto out;
 893
 894	case UI_SET_MSCBIT:
 895		retval = uinput_set_bit(arg, mscbit, MSC_MAX);
 896		goto out;
 897
 898	case UI_SET_LEDBIT:
 899		retval = uinput_set_bit(arg, ledbit, LED_MAX);
 900		goto out;
 901
 902	case UI_SET_SNDBIT:
 903		retval = uinput_set_bit(arg, sndbit, SND_MAX);
 904		goto out;
 905
 906	case UI_SET_FFBIT:
 907		retval = uinput_set_bit(arg, ffbit, FF_MAX);
 908		goto out;
 
 
 
 
 
 
 
 
 909
 910	case UI_SET_SWBIT:
 911		retval = uinput_set_bit(arg, swbit, SW_MAX);
 912		goto out;
 913
 914	case UI_SET_PROPBIT:
 915		retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
 916		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 917
 918	case UI_SET_PHYS:
 919		if (udev->state == UIST_CREATED) {
 920			retval = -EINVAL;
 921			goto out;
 922		}
 923
 924		phys = strndup_user(p, 1024);
 925		if (IS_ERR(phys)) {
 926			retval = PTR_ERR(phys);
 927			goto out;
 928		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 929
 930		kfree(udev->dev->phys);
 931		udev->dev->phys = phys;
 932		goto out;
 933
 934	case UI_BEGIN_FF_UPLOAD:
 935		retval = uinput_ff_upload_from_user(p, &ff_up);
 936		if (retval)
 937			goto out;
 
 
 
 
 
 
 
 938
 939		req = uinput_request_find(udev, ff_up.request_id);
 940		if (!req || req->code != UI_FF_UPLOAD ||
 941		    !req->u.upload.effect) {
 942			retval = -EINVAL;
 943			goto out;
 944		}
 945
 946		ff_up.retval = 0;
 947		ff_up.effect = *req->u.upload.effect;
 948		if (req->u.upload.old)
 949			ff_up.old = *req->u.upload.old;
 950		else
 951			memset(&ff_up.old, 0, sizeof(struct ff_effect));
 
 
 
 
 
 952
 953		retval = uinput_ff_upload_to_user(p, &ff_up);
 954		goto out;
 955
 956	case UI_BEGIN_FF_ERASE:
 957		if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
 958			retval = -EFAULT;
 959			goto out;
 960		}
 961
 962		req = uinput_request_find(udev, ff_erase.request_id);
 963		if (!req || req->code != UI_FF_ERASE) {
 964			retval = -EINVAL;
 965			goto out;
 966		}
 967
 968		ff_erase.retval = 0;
 969		ff_erase.effect_id = req->u.effect_id;
 970		if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
 971			retval = -EFAULT;
 972			goto out;
 973		}
 974
 975		goto out;
 976
 977	case UI_END_FF_UPLOAD:
 978		retval = uinput_ff_upload_from_user(p, &ff_up);
 979		if (retval)
 980			goto out;
 981
 982		req = uinput_request_find(udev, ff_up.request_id);
 983		if (!req || req->code != UI_FF_UPLOAD ||
 984		    !req->u.upload.effect) {
 985			retval = -EINVAL;
 986			goto out;
 987		}
 988
 989		req->retval = ff_up.retval;
 990		complete(&req->done);
 991		goto out;
 992
 993	case UI_END_FF_ERASE:
 994		if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
 995			retval = -EFAULT;
 996			goto out;
 997		}
 998
 999		req = uinput_request_find(udev, ff_erase.request_id);
1000		if (!req || req->code != UI_FF_ERASE) {
1001			retval = -EINVAL;
1002			goto out;
1003		}
1004
1005		req->retval = ff_erase.retval;
1006		complete(&req->done);
1007		goto out;
1008	}
1009
1010	size = _IOC_SIZE(cmd);
1011
1012	/* Now check variable-length commands */
1013	switch (cmd & ~IOCSIZE_MASK) {
1014	case UI_GET_SYSNAME(0):
1015		if (udev->state != UIST_CREATED) {
1016			retval = -ENOENT;
1017			goto out;
1018		}
1019		name = dev_name(&udev->dev->dev);
1020		retval = uinput_str_to_user(p, name, size);
1021		goto out;
1022
1023	case UI_ABS_SETUP & ~IOCSIZE_MASK:
1024		retval = uinput_abs_setup(udev, p, size);
1025		goto out;
1026	}
1027
1028	retval = -EINVAL;
1029 out:
1030	mutex_unlock(&udev->mutex);
1031	return retval;
1032}
1033
1034static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1035{
1036	return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
1037}
1038
1039#ifdef CONFIG_COMPAT
1040
1041/*
1042 * These IOCTLs change their size and thus their numbers between
1043 * 32 and 64 bits.
1044 */
1045#define UI_SET_PHYS_COMPAT		\
1046	_IOW(UINPUT_IOCTL_BASE, 108, compat_uptr_t)
1047#define UI_BEGIN_FF_UPLOAD_COMPAT	\
1048	_IOWR(UINPUT_IOCTL_BASE, 200, struct uinput_ff_upload_compat)
1049#define UI_END_FF_UPLOAD_COMPAT		\
1050	_IOW(UINPUT_IOCTL_BASE, 201, struct uinput_ff_upload_compat)
1051
1052static long uinput_compat_ioctl(struct file *file,
1053				unsigned int cmd, unsigned long arg)
1054{
1055	switch (cmd) {
1056	case UI_SET_PHYS_COMPAT:
1057		cmd = UI_SET_PHYS;
1058		break;
1059	case UI_BEGIN_FF_UPLOAD_COMPAT:
1060		cmd = UI_BEGIN_FF_UPLOAD;
1061		break;
1062	case UI_END_FF_UPLOAD_COMPAT:
1063		cmd = UI_END_FF_UPLOAD;
1064		break;
1065	}
1066
1067	return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
1068}
1069#endif
1070
1071static const struct file_operations uinput_fops = {
1072	.owner		= THIS_MODULE,
1073	.open		= uinput_open,
1074	.release	= uinput_release,
1075	.read		= uinput_read,
1076	.write		= uinput_write,
1077	.poll		= uinput_poll,
1078	.unlocked_ioctl	= uinput_ioctl,
1079#ifdef CONFIG_COMPAT
1080	.compat_ioctl	= uinput_compat_ioctl,
1081#endif
1082	.llseek		= no_llseek,
1083};
1084
1085static struct miscdevice uinput_misc = {
1086	.fops		= &uinput_fops,
1087	.minor		= UINPUT_MINOR,
1088	.name		= UINPUT_NAME,
1089};
1090module_misc_device(uinput_misc);
1091
1092MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
1093MODULE_ALIAS("devname:" UINPUT_NAME);
1094
 
 
 
 
 
 
 
 
 
 
1095MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
1096MODULE_DESCRIPTION("User level driver support for input subsystem");
1097MODULE_LICENSE("GPL");