2 * User level driver support for input subsystem
4 * Heavily based on evdev.c by Vojtech Pavlik
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.
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.
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
20 * Author: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
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
32 * - first public version
34 #include <linux/poll.h>
35 #include <linux/sched.h>
36 #include <linux/slab.h>
37 #include <linux/module.h>
38 #include <linux/init.h>
40 #include <linux/miscdevice.h>
41 #include <linux/uinput.h>
42 #include <linux/input/mt.h>
43 #include "../input-compat.h"
45 static int uinput_dev_event(struct input_dev *dev,
46 unsigned int type, unsigned int code, int value)
48 struct uinput_device *udev = input_get_drvdata(dev);
50 udev->buff[udev->head].type = type;
51 udev->buff[udev->head].code = code;
52 udev->buff[udev->head].value = value;
53 do_gettimeofday(&udev->buff[udev->head].time);
54 udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
56 wake_up_interruptible(&udev->waitq);
61 /* Atomically allocate an ID for the given request. Returns 0 on success. */
62 static bool uinput_request_alloc_id(struct uinput_device *udev,
63 struct uinput_request *request)
66 bool reserved = false;
68 spin_lock(&udev->requests_lock);
70 for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
71 if (!udev->requests[id]) {
73 udev->requests[id] = request;
79 spin_unlock(&udev->requests_lock);
83 static struct uinput_request *uinput_request_find(struct uinput_device *udev,
86 /* Find an input request, by ID. Returns NULL if the ID isn't valid. */
87 if (id >= UINPUT_NUM_REQUESTS)
90 return udev->requests[id];
93 static int uinput_request_reserve_slot(struct uinput_device *udev,
94 struct uinput_request *request)
96 /* Allocate slot. If none are available right away, wait. */
97 return wait_event_interruptible(udev->requests_waitq,
98 uinput_request_alloc_id(udev, request));
101 static void uinput_request_done(struct uinput_device *udev,
102 struct uinput_request *request)
104 /* Mark slot as available */
105 udev->requests[request->id] = NULL;
106 wake_up(&udev->requests_waitq);
108 complete(&request->done);
111 static int uinput_request_send(struct uinput_device *udev,
112 struct uinput_request *request)
116 retval = mutex_lock_interruptible(&udev->mutex);
120 if (udev->state != UIST_CREATED) {
125 init_completion(&request->done);
128 * Tell our userspace application about this new request
129 * by queueing an input event.
131 uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
134 mutex_unlock(&udev->mutex);
138 static int uinput_request_submit(struct uinput_device *udev,
139 struct uinput_request *request)
143 error = uinput_request_reserve_slot(udev, request);
147 error = uinput_request_send(udev, request);
149 uinput_request_done(udev, request);
153 wait_for_completion(&request->done);
154 return request->retval;
158 * Fail all outstanding requests so handlers don't wait for the userspace
159 * to finish processing them.
161 static void uinput_flush_requests(struct uinput_device *udev)
163 struct uinput_request *request;
166 spin_lock(&udev->requests_lock);
168 for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
169 request = udev->requests[i];
171 request->retval = -ENODEV;
172 uinput_request_done(udev, request);
176 spin_unlock(&udev->requests_lock);
179 static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
181 uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
184 static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
186 uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
189 static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
191 return uinput_dev_event(dev, EV_FF, effect_id, value);
194 static int uinput_dev_upload_effect(struct input_dev *dev,
195 struct ff_effect *effect,
196 struct ff_effect *old)
198 struct uinput_device *udev = input_get_drvdata(dev);
199 struct uinput_request request;
202 * uinput driver does not currently support periodic effects with
203 * custom waveform since it does not have a way to pass buffer of
204 * samples (custom_data) to userspace. If ever there is a device
205 * supporting custom waveforms we would need to define an additional
206 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
208 if (effect->type == FF_PERIODIC &&
209 effect->u.periodic.waveform == FF_CUSTOM)
212 request.code = UI_FF_UPLOAD;
213 request.u.upload.effect = effect;
214 request.u.upload.old = old;
216 return uinput_request_submit(udev, &request);
219 static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
221 struct uinput_device *udev = input_get_drvdata(dev);
222 struct uinput_request request;
224 if (!test_bit(EV_FF, dev->evbit))
227 request.code = UI_FF_ERASE;
228 request.u.effect_id = effect_id;
230 return uinput_request_submit(udev, &request);
233 static void uinput_destroy_device(struct uinput_device *udev)
235 const char *name, *phys;
236 struct input_dev *dev = udev->dev;
237 enum uinput_state old_state = udev->state;
239 udev->state = UIST_NEW_DEVICE;
244 if (old_state == UIST_CREATED) {
245 uinput_flush_requests(udev);
246 input_unregister_device(dev);
248 input_free_device(dev);
256 static int uinput_create_device(struct uinput_device *udev)
258 struct input_dev *dev = udev->dev;
261 if (udev->state != UIST_SETUP_COMPLETE) {
262 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
266 if (test_bit(ABS_MT_SLOT, dev->absbit)) {
267 nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
268 error = input_mt_init_slots(dev, nslot, 0);
271 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
272 input_set_events_per_packet(dev, 60);
275 if (test_bit(EV_FF, dev->evbit) && !udev->ff_effects_max) {
276 printk(KERN_DEBUG "%s: ff_effects_max should be non-zero when FF_BIT is set\n",
282 if (udev->ff_effects_max) {
283 error = input_ff_create(dev, udev->ff_effects_max);
287 dev->ff->upload = uinput_dev_upload_effect;
288 dev->ff->erase = uinput_dev_erase_effect;
289 dev->ff->playback = uinput_dev_playback;
290 dev->ff->set_gain = uinput_dev_set_gain;
291 dev->ff->set_autocenter = uinput_dev_set_autocenter;
294 error = input_register_device(udev->dev);
298 udev->state = UIST_CREATED;
302 fail2: input_ff_destroy(dev);
303 fail1: uinput_destroy_device(udev);
307 static int uinput_open(struct inode *inode, struct file *file)
309 struct uinput_device *newdev;
311 newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
315 mutex_init(&newdev->mutex);
316 spin_lock_init(&newdev->requests_lock);
317 init_waitqueue_head(&newdev->requests_waitq);
318 init_waitqueue_head(&newdev->waitq);
319 newdev->state = UIST_NEW_DEVICE;
321 file->private_data = newdev;
322 nonseekable_open(inode, file);
327 static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code,
328 const struct input_absinfo *abs)
335 if ((min != 0 || max != 0) && max <= min) {
337 "%s: invalid abs[%02x] min:%d max:%d\n",
338 UINPUT_NAME, code, min, max);
342 if (abs->flat > max - min) {
344 "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n",
345 UINPUT_NAME, code, abs->flat, min, max);
352 static int uinput_validate_absbits(struct input_dev *dev)
357 if (!test_bit(EV_ABS, dev->evbit))
361 * Check if absmin/absmax/absfuzz/absflat are sane.
364 for_each_set_bit(cnt, dev->absbit, ABS_CNT) {
368 error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]);
376 static int uinput_allocate_device(struct uinput_device *udev)
378 udev->dev = input_allocate_device();
382 udev->dev->event = uinput_dev_event;
383 input_set_drvdata(udev->dev, udev);
388 static int uinput_dev_setup(struct uinput_device *udev,
389 struct uinput_setup __user *arg)
391 struct uinput_setup setup;
392 struct input_dev *dev;
394 if (udev->state == UIST_CREATED)
397 if (copy_from_user(&setup, arg, sizeof(setup)))
405 udev->ff_effects_max = setup.ff_effects_max;
408 dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL);
412 udev->state = UIST_SETUP_COMPLETE;
416 static int uinput_abs_setup(struct uinput_device *udev,
417 struct uinput_setup __user *arg, size_t size)
419 struct uinput_abs_setup setup = {};
420 struct input_dev *dev;
423 if (size > sizeof(setup))
426 if (udev->state == UIST_CREATED)
429 if (copy_from_user(&setup, arg, size))
432 if (setup.code > ABS_MAX)
437 error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo);
441 input_alloc_absinfo(dev);
445 set_bit(setup.code, dev->absbit);
446 dev->absinfo[setup.code] = setup.absinfo;
450 /* legacy setup via write() */
451 static int uinput_setup_device_legacy(struct uinput_device *udev,
452 const char __user *buffer, size_t count)
454 struct uinput_user_dev *user_dev;
455 struct input_dev *dev;
459 if (count != sizeof(struct uinput_user_dev))
463 retval = uinput_allocate_device(udev);
470 user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
471 if (IS_ERR(user_dev))
472 return PTR_ERR(user_dev);
474 udev->ff_effects_max = user_dev->ff_effects_max;
476 /* Ensure name is filled in */
477 if (!user_dev->name[0]) {
483 dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
490 dev->id.bustype = user_dev->id.bustype;
491 dev->id.vendor = user_dev->id.vendor;
492 dev->id.product = user_dev->id.product;
493 dev->id.version = user_dev->id.version;
495 for (i = 0; i < ABS_CNT; i++) {
496 input_abs_set_max(dev, i, user_dev->absmax[i]);
497 input_abs_set_min(dev, i, user_dev->absmin[i]);
498 input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
499 input_abs_set_flat(dev, i, user_dev->absflat[i]);
502 retval = uinput_validate_absbits(dev);
506 udev->state = UIST_SETUP_COMPLETE;
514 static ssize_t uinput_inject_events(struct uinput_device *udev,
515 const char __user *buffer, size_t count)
517 struct input_event ev;
520 if (count != 0 && count < input_event_size())
523 while (bytes + input_event_size() <= count) {
525 * Note that even if some events were fetched successfully
526 * we are still going to return EFAULT instead of partial
527 * count to let userspace know that it got it's buffers
530 if (input_event_from_user(buffer + bytes, &ev))
533 input_event(udev->dev, ev.type, ev.code, ev.value);
534 bytes += input_event_size();
540 static ssize_t uinput_write(struct file *file, const char __user *buffer,
541 size_t count, loff_t *ppos)
543 struct uinput_device *udev = file->private_data;
549 retval = mutex_lock_interruptible(&udev->mutex);
553 retval = udev->state == UIST_CREATED ?
554 uinput_inject_events(udev, buffer, count) :
555 uinput_setup_device_legacy(udev, buffer, count);
557 mutex_unlock(&udev->mutex);
562 static bool uinput_fetch_next_event(struct uinput_device *udev,
563 struct input_event *event)
567 spin_lock_irq(&udev->dev->event_lock);
569 have_event = udev->head != udev->tail;
571 *event = udev->buff[udev->tail];
572 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
575 spin_unlock_irq(&udev->dev->event_lock);
580 static ssize_t uinput_events_to_user(struct uinput_device *udev,
581 char __user *buffer, size_t count)
583 struct input_event event;
586 while (read + input_event_size() <= count &&
587 uinput_fetch_next_event(udev, &event)) {
589 if (input_event_to_user(buffer + read, &event))
592 read += input_event_size();
598 static ssize_t uinput_read(struct file *file, char __user *buffer,
599 size_t count, loff_t *ppos)
601 struct uinput_device *udev = file->private_data;
604 if (count != 0 && count < input_event_size())
608 retval = mutex_lock_interruptible(&udev->mutex);
612 if (udev->state != UIST_CREATED)
614 else if (udev->head == udev->tail &&
615 (file->f_flags & O_NONBLOCK))
618 retval = uinput_events_to_user(udev, buffer, count);
620 mutex_unlock(&udev->mutex);
622 if (retval || count == 0)
625 if (!(file->f_flags & O_NONBLOCK))
626 retval = wait_event_interruptible(udev->waitq,
627 udev->head != udev->tail ||
628 udev->state != UIST_CREATED);
629 } while (retval == 0);
634 static unsigned int uinput_poll(struct file *file, poll_table *wait)
636 struct uinput_device *udev = file->private_data;
638 poll_wait(file, &udev->waitq, wait);
640 if (udev->head != udev->tail)
641 return POLLIN | POLLRDNORM;
646 static int uinput_release(struct inode *inode, struct file *file)
648 struct uinput_device *udev = file->private_data;
650 uinput_destroy_device(udev);
657 struct uinput_ff_upload_compat {
660 struct ff_effect_compat effect;
661 struct ff_effect_compat old;
664 static int uinput_ff_upload_to_user(char __user *buffer,
665 const struct uinput_ff_upload *ff_up)
667 if (in_compat_syscall()) {
668 struct uinput_ff_upload_compat ff_up_compat;
670 ff_up_compat.request_id = ff_up->request_id;
671 ff_up_compat.retval = ff_up->retval;
673 * It so happens that the pointer that gives us the trouble
674 * is the last field in the structure. Since we don't support
675 * custom waveforms in uinput anyway we can just copy the whole
676 * thing (to the compat size) and ignore the pointer.
678 memcpy(&ff_up_compat.effect, &ff_up->effect,
679 sizeof(struct ff_effect_compat));
680 memcpy(&ff_up_compat.old, &ff_up->old,
681 sizeof(struct ff_effect_compat));
683 if (copy_to_user(buffer, &ff_up_compat,
684 sizeof(struct uinput_ff_upload_compat)))
687 if (copy_to_user(buffer, ff_up,
688 sizeof(struct uinput_ff_upload)))
695 static int uinput_ff_upload_from_user(const char __user *buffer,
696 struct uinput_ff_upload *ff_up)
698 if (in_compat_syscall()) {
699 struct uinput_ff_upload_compat ff_up_compat;
701 if (copy_from_user(&ff_up_compat, buffer,
702 sizeof(struct uinput_ff_upload_compat)))
705 ff_up->request_id = ff_up_compat.request_id;
706 ff_up->retval = ff_up_compat.retval;
707 memcpy(&ff_up->effect, &ff_up_compat.effect,
708 sizeof(struct ff_effect_compat));
709 memcpy(&ff_up->old, &ff_up_compat.old,
710 sizeof(struct ff_effect_compat));
713 if (copy_from_user(ff_up, buffer,
714 sizeof(struct uinput_ff_upload)))
723 static int uinput_ff_upload_to_user(char __user *buffer,
724 const struct uinput_ff_upload *ff_up)
726 if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
732 static int uinput_ff_upload_from_user(const char __user *buffer,
733 struct uinput_ff_upload *ff_up)
735 if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
743 #define uinput_set_bit(_arg, _bit, _max) \
746 if (udev->state == UIST_CREATED) \
748 else if ((_arg) > (_max)) \
750 else set_bit((_arg), udev->dev->_bit); \
754 static int uinput_str_to_user(void __user *dest, const char *str,
757 char __user *p = dest;
766 len = strlen(str) + 1;
770 ret = copy_to_user(p, str, len);
774 /* force terminating '\0' */
775 ret = put_user(0, p + len - 1);
776 return ret ? -EFAULT : len;
779 static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
780 unsigned long arg, void __user *p)
783 struct uinput_device *udev = file->private_data;
784 struct uinput_ff_upload ff_up;
785 struct uinput_ff_erase ff_erase;
786 struct uinput_request *req;
791 retval = mutex_lock_interruptible(&udev->mutex);
796 retval = uinput_allocate_device(udev);
803 if (put_user(UINPUT_VERSION,
804 (unsigned int __user *)p))
809 retval = uinput_create_device(udev);
813 uinput_destroy_device(udev);
817 retval = uinput_dev_setup(udev, p);
820 /* UI_ABS_SETUP is handled in the variable size ioctls */
823 retval = uinput_set_bit(arg, evbit, EV_MAX);
827 retval = uinput_set_bit(arg, keybit, KEY_MAX);
831 retval = uinput_set_bit(arg, relbit, REL_MAX);
835 retval = uinput_set_bit(arg, absbit, ABS_MAX);
839 retval = uinput_set_bit(arg, mscbit, MSC_MAX);
843 retval = uinput_set_bit(arg, ledbit, LED_MAX);
847 retval = uinput_set_bit(arg, sndbit, SND_MAX);
851 retval = uinput_set_bit(arg, ffbit, FF_MAX);
855 retval = uinput_set_bit(arg, swbit, SW_MAX);
859 retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
863 if (udev->state == UIST_CREATED) {
868 phys = strndup_user(p, 1024);
870 retval = PTR_ERR(phys);
874 kfree(udev->dev->phys);
875 udev->dev->phys = phys;
878 case UI_BEGIN_FF_UPLOAD:
879 retval = uinput_ff_upload_from_user(p, &ff_up);
883 req = uinput_request_find(udev, ff_up.request_id);
884 if (!req || req->code != UI_FF_UPLOAD ||
885 !req->u.upload.effect) {
891 ff_up.effect = *req->u.upload.effect;
892 if (req->u.upload.old)
893 ff_up.old = *req->u.upload.old;
895 memset(&ff_up.old, 0, sizeof(struct ff_effect));
897 retval = uinput_ff_upload_to_user(p, &ff_up);
900 case UI_BEGIN_FF_ERASE:
901 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
906 req = uinput_request_find(udev, ff_erase.request_id);
907 if (!req || req->code != UI_FF_ERASE) {
913 ff_erase.effect_id = req->u.effect_id;
914 if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
921 case UI_END_FF_UPLOAD:
922 retval = uinput_ff_upload_from_user(p, &ff_up);
926 req = uinput_request_find(udev, ff_up.request_id);
927 if (!req || req->code != UI_FF_UPLOAD ||
928 !req->u.upload.effect) {
933 req->retval = ff_up.retval;
934 uinput_request_done(udev, req);
937 case UI_END_FF_ERASE:
938 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
943 req = uinput_request_find(udev, ff_erase.request_id);
944 if (!req || req->code != UI_FF_ERASE) {
949 req->retval = ff_erase.retval;
950 uinput_request_done(udev, req);
954 size = _IOC_SIZE(cmd);
956 /* Now check variable-length commands */
957 switch (cmd & ~IOCSIZE_MASK) {
958 case UI_GET_SYSNAME(0):
959 if (udev->state != UIST_CREATED) {
963 name = dev_name(&udev->dev->dev);
964 retval = uinput_str_to_user(p, name, size);
967 case UI_ABS_SETUP & ~IOCSIZE_MASK:
968 retval = uinput_abs_setup(udev, p, size);
974 mutex_unlock(&udev->mutex);
978 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
980 return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
985 #define UI_SET_PHYS_COMPAT _IOW(UINPUT_IOCTL_BASE, 108, compat_uptr_t)
987 static long uinput_compat_ioctl(struct file *file,
988 unsigned int cmd, unsigned long arg)
990 if (cmd == UI_SET_PHYS_COMPAT)
993 return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
997 static const struct file_operations uinput_fops = {
998 .owner = THIS_MODULE,
1000 .release = uinput_release,
1001 .read = uinput_read,
1002 .write = uinput_write,
1003 .poll = uinput_poll,
1004 .unlocked_ioctl = uinput_ioctl,
1005 #ifdef CONFIG_COMPAT
1006 .compat_ioctl = uinput_compat_ioctl,
1008 .llseek = no_llseek,
1011 static struct miscdevice uinput_misc = {
1012 .fops = &uinput_fops,
1013 .minor = UINPUT_MINOR,
1014 .name = UINPUT_NAME,
1016 module_misc_device(uinput_misc);
1018 MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
1019 MODULE_ALIAS("devname:" UINPUT_NAME);
1021 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
1022 MODULE_DESCRIPTION("User level driver support for input subsystem");
1023 MODULE_LICENSE("GPL");
1024 MODULE_VERSION("0.3");