a94c5e05006b082f49376c1e42bffabae6dda5a0
[muen/linux.git] / drivers / input / misc / uinput.c
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
49 enum uinput_state { UIST_NEW_DEVICE, UIST_SETUP_COMPLETE, UIST_CREATED };
50
51 struct 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
67 struct 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
83 static 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. */
103 static 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
124 static 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
134 static 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
142 static 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
153 static 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
180 static 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  */
209 static 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
227 static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
228 {
229         uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
230 }
231
232 static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
233 {
234         uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
235 }
236
237 static 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
242 static 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
267 static 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
281 static 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
293 static 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
316 static 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
385 static 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
405 static 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
430 static 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
454 static 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
482 static 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() */
517 static 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
580 static 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
606 static 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
628 static 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
646 static 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
664 static 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
700 static unsigned int 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 POLLIN | POLLRDNORM;
708
709         return 0;
710 }
711
712 static 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
723 struct 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
730 static 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
761 static 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
789 static 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
798 static 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
820 static 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
845 static 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
1045 static 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
1054 static 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
1064 static 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
1078 static struct miscdevice uinput_misc = {
1079         .fops           = &uinput_fops,
1080         .minor          = UINPUT_MINOR,
1081         .name           = UINPUT_NAME,
1082 };
1083 module_misc_device(uinput_misc);
1084
1085 MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
1086 MODULE_ALIAS("devname:" UINPUT_NAME);
1087
1088 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
1089 MODULE_DESCRIPTION("User level driver support for input subsystem");
1090 MODULE_LICENSE("GPL");