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 * 0.3 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
30 * - first public version
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>
38 #include <linux/miscdevice.h>
39 #include <linux/uinput.h>
40 #include <linux/input/mt.h>
41 #include "../input-compat.h"
43 static int uinput_dev_event(struct input_dev *dev,
44 unsigned int type, unsigned int code, int value)
46 struct uinput_device *udev = input_get_drvdata(dev);
48 udev->buff[udev->head].type = type;
49 udev->buff[udev->head].code = code;
50 udev->buff[udev->head].value = value;
51 do_gettimeofday(&udev->buff[udev->head].time);
52 udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
54 wake_up_interruptible(&udev->waitq);
59 /* Atomically allocate an ID for the given request. Returns 0 on success. */
60 static bool uinput_request_alloc_id(struct uinput_device *udev,
61 struct uinput_request *request)
64 bool reserved = false;
66 spin_lock(&udev->requests_lock);
68 for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
69 if (!udev->requests[id]) {
71 udev->requests[id] = request;
77 spin_unlock(&udev->requests_lock);
81 static struct uinput_request *uinput_request_find(struct uinput_device *udev,
84 /* Find an input request, by ID. Returns NULL if the ID isn't valid. */
85 if (id >= UINPUT_NUM_REQUESTS)
88 return udev->requests[id];
91 static int uinput_request_reserve_slot(struct uinput_device *udev,
92 struct uinput_request *request)
94 /* Allocate slot. If none are available right away, wait. */
95 return wait_event_interruptible(udev->requests_waitq,
96 uinput_request_alloc_id(udev, request));
99 static void uinput_request_done(struct uinput_device *udev,
100 struct uinput_request *request)
102 /* Mark slot as available */
103 udev->requests[request->id] = NULL;
104 wake_up(&udev->requests_waitq);
106 complete(&request->done);
109 static int uinput_request_send(struct uinput_device *udev,
110 struct uinput_request *request)
114 retval = mutex_lock_interruptible(&udev->mutex);
118 if (udev->state != UIST_CREATED) {
123 init_completion(&request->done);
126 * Tell our userspace application about this new request
127 * by queueing an input event.
129 uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
132 mutex_unlock(&udev->mutex);
136 static int uinput_request_submit(struct uinput_device *udev,
137 struct uinput_request *request)
141 error = uinput_request_reserve_slot(udev, request);
145 error = uinput_request_send(udev, request);
147 uinput_request_done(udev, request);
151 wait_for_completion(&request->done);
152 return request->retval;
156 * Fail all outstanding requests so handlers don't wait for the userspace
157 * to finish processing them.
159 static void uinput_flush_requests(struct uinput_device *udev)
161 struct uinput_request *request;
164 spin_lock(&udev->requests_lock);
166 for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
167 request = udev->requests[i];
169 request->retval = -ENODEV;
170 uinput_request_done(udev, request);
174 spin_unlock(&udev->requests_lock);
177 static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
179 uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
182 static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
184 uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
187 static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
189 return uinput_dev_event(dev, EV_FF, effect_id, value);
192 static int uinput_dev_upload_effect(struct input_dev *dev,
193 struct ff_effect *effect,
194 struct ff_effect *old)
196 struct uinput_device *udev = input_get_drvdata(dev);
197 struct uinput_request request;
200 * uinput driver does not currently support periodic effects with
201 * custom waveform since it does not have a way to pass buffer of
202 * samples (custom_data) to userspace. If ever there is a device
203 * supporting custom waveforms we would need to define an additional
204 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
206 if (effect->type == FF_PERIODIC &&
207 effect->u.periodic.waveform == FF_CUSTOM)
210 request.code = UI_FF_UPLOAD;
211 request.u.upload.effect = effect;
212 request.u.upload.old = old;
214 return uinput_request_submit(udev, &request);
217 static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
219 struct uinput_device *udev = input_get_drvdata(dev);
220 struct uinput_request request;
222 if (!test_bit(EV_FF, dev->evbit))
225 request.code = UI_FF_ERASE;
226 request.u.effect_id = effect_id;
228 return uinput_request_submit(udev, &request);
231 static void uinput_destroy_device(struct uinput_device *udev)
233 const char *name, *phys;
234 struct input_dev *dev = udev->dev;
235 enum uinput_state old_state = udev->state;
237 udev->state = UIST_NEW_DEVICE;
242 if (old_state == UIST_CREATED) {
243 uinput_flush_requests(udev);
244 input_unregister_device(dev);
246 input_free_device(dev);
254 static int uinput_create_device(struct uinput_device *udev)
256 struct input_dev *dev = udev->dev;
259 if (udev->state != UIST_SETUP_COMPLETE) {
260 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
264 if (udev->ff_effects_max) {
265 error = input_ff_create(dev, udev->ff_effects_max);
269 dev->ff->upload = uinput_dev_upload_effect;
270 dev->ff->erase = uinput_dev_erase_effect;
271 dev->ff->playback = uinput_dev_playback;
272 dev->ff->set_gain = uinput_dev_set_gain;
273 dev->ff->set_autocenter = uinput_dev_set_autocenter;
276 error = input_register_device(udev->dev);
280 udev->state = UIST_CREATED;
284 fail2: input_ff_destroy(dev);
285 fail1: uinput_destroy_device(udev);
289 static int uinput_open(struct inode *inode, struct file *file)
291 struct uinput_device *newdev;
293 newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
297 mutex_init(&newdev->mutex);
298 spin_lock_init(&newdev->requests_lock);
299 init_waitqueue_head(&newdev->requests_waitq);
300 init_waitqueue_head(&newdev->waitq);
301 newdev->state = UIST_NEW_DEVICE;
303 file->private_data = newdev;
304 nonseekable_open(inode, file);
309 static int uinput_validate_absbits(struct input_dev *dev)
314 for (cnt = 0; cnt < ABS_CNT; cnt++) {
316 if (!test_bit(cnt, dev->absbit))
319 min = input_abs_get_min(dev, cnt);
320 max = input_abs_get_max(dev, cnt);
322 if ((min != 0 || max != 0) && max <= min) {
324 "%s: invalid abs[%02x] min:%d max:%d\n",
326 input_abs_get_min(dev, cnt),
327 input_abs_get_max(dev, cnt));
332 if (input_abs_get_flat(dev, cnt) >
333 input_abs_get_max(dev, cnt) - input_abs_get_min(dev, cnt)) {
335 "%s: abs_flat #%02x out of range: %d "
338 input_abs_get_flat(dev, cnt),
339 input_abs_get_min(dev, cnt),
340 input_abs_get_max(dev, cnt));
348 static int uinput_allocate_device(struct uinput_device *udev)
350 udev->dev = input_allocate_device();
354 udev->dev->event = uinput_dev_event;
355 input_set_drvdata(udev->dev, udev);
360 static int uinput_setup_device(struct uinput_device *udev,
361 const char __user *buffer, size_t count)
363 struct uinput_user_dev *user_dev;
364 struct input_dev *dev;
368 if (count != sizeof(struct uinput_user_dev))
372 retval = uinput_allocate_device(udev);
379 user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
380 if (IS_ERR(user_dev))
381 return PTR_ERR(user_dev);
383 udev->ff_effects_max = user_dev->ff_effects_max;
385 /* Ensure name is filled in */
386 if (!user_dev->name[0]) {
392 dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
399 dev->id.bustype = user_dev->id.bustype;
400 dev->id.vendor = user_dev->id.vendor;
401 dev->id.product = user_dev->id.product;
402 dev->id.version = user_dev->id.version;
404 for (i = 0; i < ABS_CNT; i++) {
405 input_abs_set_max(dev, i, user_dev->absmax[i]);
406 input_abs_set_min(dev, i, user_dev->absmin[i]);
407 input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
408 input_abs_set_flat(dev, i, user_dev->absflat[i]);
411 /* check if absmin/absmax/absfuzz/absflat are filled as
412 * told in Documentation/input/input-programming.txt */
413 if (test_bit(EV_ABS, dev->evbit)) {
414 retval = uinput_validate_absbits(dev);
417 if (test_bit(ABS_MT_SLOT, dev->absbit)) {
418 int nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
419 input_mt_init_slots(dev, nslot, 0);
420 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
421 input_set_events_per_packet(dev, 60);
425 udev->state = UIST_SETUP_COMPLETE;
433 static ssize_t uinput_inject_event(struct uinput_device *udev,
434 const char __user *buffer, size_t count)
436 struct input_event ev;
438 if (count < input_event_size())
441 if (input_event_from_user(buffer, &ev))
444 input_event(udev->dev, ev.type, ev.code, ev.value);
446 return input_event_size();
449 static ssize_t uinput_write(struct file *file, const char __user *buffer,
450 size_t count, loff_t *ppos)
452 struct uinput_device *udev = file->private_data;
458 retval = mutex_lock_interruptible(&udev->mutex);
462 retval = udev->state == UIST_CREATED ?
463 uinput_inject_event(udev, buffer, count) :
464 uinput_setup_device(udev, buffer, count);
466 mutex_unlock(&udev->mutex);
471 static bool uinput_fetch_next_event(struct uinput_device *udev,
472 struct input_event *event)
476 spin_lock_irq(&udev->dev->event_lock);
478 have_event = udev->head != udev->tail;
480 *event = udev->buff[udev->tail];
481 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
484 spin_unlock_irq(&udev->dev->event_lock);
489 static ssize_t uinput_events_to_user(struct uinput_device *udev,
490 char __user *buffer, size_t count)
492 struct input_event event;
495 while (read + input_event_size() <= count &&
496 uinput_fetch_next_event(udev, &event)) {
498 if (input_event_to_user(buffer + read, &event))
501 read += input_event_size();
507 static ssize_t uinput_read(struct file *file, char __user *buffer,
508 size_t count, loff_t *ppos)
510 struct uinput_device *udev = file->private_data;
513 if (count != 0 && count < input_event_size())
517 retval = mutex_lock_interruptible(&udev->mutex);
521 if (udev->state != UIST_CREATED)
523 else if (udev->head == udev->tail &&
524 (file->f_flags & O_NONBLOCK))
527 retval = uinput_events_to_user(udev, buffer, count);
529 mutex_unlock(&udev->mutex);
531 if (retval || count == 0)
534 if (!(file->f_flags & O_NONBLOCK))
535 retval = wait_event_interruptible(udev->waitq,
536 udev->head != udev->tail ||
537 udev->state != UIST_CREATED);
538 } while (retval == 0);
543 static unsigned int uinput_poll(struct file *file, poll_table *wait)
545 struct uinput_device *udev = file->private_data;
547 poll_wait(file, &udev->waitq, wait);
549 if (udev->head != udev->tail)
550 return POLLIN | POLLRDNORM;
555 static int uinput_release(struct inode *inode, struct file *file)
557 struct uinput_device *udev = file->private_data;
559 uinput_destroy_device(udev);
566 struct uinput_ff_upload_compat {
569 struct ff_effect_compat effect;
570 struct ff_effect_compat old;
573 static int uinput_ff_upload_to_user(char __user *buffer,
574 const struct uinput_ff_upload *ff_up)
576 if (INPUT_COMPAT_TEST) {
577 struct uinput_ff_upload_compat ff_up_compat;
579 ff_up_compat.request_id = ff_up->request_id;
580 ff_up_compat.retval = ff_up->retval;
582 * It so happens that the pointer that gives us the trouble
583 * is the last field in the structure. Since we don't support
584 * custom waveforms in uinput anyway we can just copy the whole
585 * thing (to the compat size) and ignore the pointer.
587 memcpy(&ff_up_compat.effect, &ff_up->effect,
588 sizeof(struct ff_effect_compat));
589 memcpy(&ff_up_compat.old, &ff_up->old,
590 sizeof(struct ff_effect_compat));
592 if (copy_to_user(buffer, &ff_up_compat,
593 sizeof(struct uinput_ff_upload_compat)))
596 if (copy_to_user(buffer, ff_up,
597 sizeof(struct uinput_ff_upload)))
604 static int uinput_ff_upload_from_user(const char __user *buffer,
605 struct uinput_ff_upload *ff_up)
607 if (INPUT_COMPAT_TEST) {
608 struct uinput_ff_upload_compat ff_up_compat;
610 if (copy_from_user(&ff_up_compat, buffer,
611 sizeof(struct uinput_ff_upload_compat)))
614 ff_up->request_id = ff_up_compat.request_id;
615 ff_up->retval = ff_up_compat.retval;
616 memcpy(&ff_up->effect, &ff_up_compat.effect,
617 sizeof(struct ff_effect_compat));
618 memcpy(&ff_up->old, &ff_up_compat.old,
619 sizeof(struct ff_effect_compat));
622 if (copy_from_user(ff_up, buffer,
623 sizeof(struct uinput_ff_upload)))
632 static int uinput_ff_upload_to_user(char __user *buffer,
633 const struct uinput_ff_upload *ff_up)
635 if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
641 static int uinput_ff_upload_from_user(const char __user *buffer,
642 struct uinput_ff_upload *ff_up)
644 if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
652 #define uinput_set_bit(_arg, _bit, _max) \
655 if (udev->state == UIST_CREATED) \
657 else if ((_arg) > (_max)) \
659 else set_bit((_arg), udev->dev->_bit); \
663 static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
664 unsigned long arg, void __user *p)
667 struct uinput_device *udev = file->private_data;
668 struct uinput_ff_upload ff_up;
669 struct uinput_ff_erase ff_erase;
670 struct uinput_request *req;
673 retval = mutex_lock_interruptible(&udev->mutex);
678 retval = uinput_allocate_device(udev);
685 retval = uinput_create_device(udev);
689 uinput_destroy_device(udev);
693 retval = uinput_set_bit(arg, evbit, EV_MAX);
697 retval = uinput_set_bit(arg, keybit, KEY_MAX);
701 retval = uinput_set_bit(arg, relbit, REL_MAX);
705 retval = uinput_set_bit(arg, absbit, ABS_MAX);
709 retval = uinput_set_bit(arg, mscbit, MSC_MAX);
713 retval = uinput_set_bit(arg, ledbit, LED_MAX);
717 retval = uinput_set_bit(arg, sndbit, SND_MAX);
721 retval = uinput_set_bit(arg, ffbit, FF_MAX);
725 retval = uinput_set_bit(arg, swbit, SW_MAX);
729 retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
733 if (udev->state == UIST_CREATED) {
738 phys = strndup_user(p, 1024);
740 retval = PTR_ERR(phys);
744 kfree(udev->dev->phys);
745 udev->dev->phys = phys;
748 case UI_BEGIN_FF_UPLOAD:
749 retval = uinput_ff_upload_from_user(p, &ff_up);
753 req = uinput_request_find(udev, ff_up.request_id);
754 if (!req || req->code != UI_FF_UPLOAD ||
755 !req->u.upload.effect) {
761 ff_up.effect = *req->u.upload.effect;
762 if (req->u.upload.old)
763 ff_up.old = *req->u.upload.old;
765 memset(&ff_up.old, 0, sizeof(struct ff_effect));
767 retval = uinput_ff_upload_to_user(p, &ff_up);
770 case UI_BEGIN_FF_ERASE:
771 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
776 req = uinput_request_find(udev, ff_erase.request_id);
777 if (!req || req->code != UI_FF_ERASE) {
783 ff_erase.effect_id = req->u.effect_id;
784 if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
791 case UI_END_FF_UPLOAD:
792 retval = uinput_ff_upload_from_user(p, &ff_up);
796 req = uinput_request_find(udev, ff_up.request_id);
797 if (!req || req->code != UI_FF_UPLOAD ||
798 !req->u.upload.effect) {
803 req->retval = ff_up.retval;
804 uinput_request_done(udev, req);
807 case UI_END_FF_ERASE:
808 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
813 req = uinput_request_find(udev, ff_erase.request_id);
814 if (!req || req->code != UI_FF_ERASE) {
819 req->retval = ff_erase.retval;
820 uinput_request_done(udev, req);
828 mutex_unlock(&udev->mutex);
832 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
834 return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
838 static long uinput_compat_ioctl(struct file *file,
839 unsigned int cmd, unsigned long arg)
841 return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
845 static const struct file_operations uinput_fops = {
846 .owner = THIS_MODULE,
848 .release = uinput_release,
850 .write = uinput_write,
852 .unlocked_ioctl = uinput_ioctl,
854 .compat_ioctl = uinput_compat_ioctl,
859 static struct miscdevice uinput_misc = {
860 .fops = &uinput_fops,
861 .minor = UINPUT_MINOR,
864 MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
865 MODULE_ALIAS("devname:" UINPUT_NAME);
867 static int __init uinput_init(void)
869 return misc_register(&uinput_misc);
872 static void __exit uinput_exit(void)
874 misc_deregister(&uinput_misc);
877 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
878 MODULE_DESCRIPTION("User level driver support for input subsystem");
879 MODULE_LICENSE("GPL");
880 MODULE_VERSION("0.3");
882 module_init(uinput_init);
883 module_exit(uinput_exit);