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, unsigned int type, unsigned int code, int value)
45 struct uinput_device *udev = input_get_drvdata(dev);
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;
53 wake_up_interruptible(&udev->waitq);
58 /* Atomically allocate an ID for the given request. Returns 0 on success. */
59 static int uinput_request_alloc_id(struct uinput_device *udev, struct uinput_request *request)
64 spin_lock(&udev->requests_lock);
66 for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
67 if (!udev->requests[id]) {
69 udev->requests[id] = request;
75 spin_unlock(&udev->requests_lock);
79 static struct uinput_request *uinput_request_find(struct uinput_device *udev, int id)
81 /* Find an input request, by ID. Returns NULL if the ID isn't valid. */
82 if (id >= UINPUT_NUM_REQUESTS || id < 0)
85 return udev->requests[id];
88 static inline int uinput_request_reserve_slot(struct uinput_device *udev, struct uinput_request *request)
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));
95 static void uinput_request_done(struct uinput_device *udev, struct uinput_request *request)
97 /* Mark slot as available */
98 udev->requests[request->id] = NULL;
99 wake_up(&udev->requests_waitq);
101 complete(&request->done);
104 static int uinput_request_submit(struct uinput_device *udev, struct uinput_request *request)
108 retval = uinput_request_reserve_slot(udev, request);
112 retval = mutex_lock_interruptible(&udev->mutex);
116 if (udev->state != UIST_CREATED) {
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);
125 mutex_unlock(&udev->mutex);
130 * Fail all ouitstanding requests so handlers don't wait for the userspace
131 * to finish processing them.
133 static void uinput_flush_requests(struct uinput_device *udev)
135 struct uinput_request *request;
138 spin_lock(&udev->requests_lock);
140 for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
141 request = udev->requests[i];
143 request->retval = -ENODEV;
144 uinput_request_done(udev, request);
148 spin_unlock(&udev->requests_lock);
151 static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
153 uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
156 static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
158 uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
161 static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
163 return uinput_dev_event(dev, EV_FF, effect_id, value);
166 static int uinput_dev_upload_effect(struct input_dev *dev, struct ff_effect *effect, struct ff_effect *old)
168 struct uinput_device *udev = input_get_drvdata(dev);
169 struct uinput_request request;
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.
179 if (effect->type == FF_PERIODIC &&
180 effect->u.periodic.waveform == FF_CUSTOM)
184 init_completion(&request.done);
185 request.code = UI_FF_UPLOAD;
186 request.u.upload.effect = effect;
187 request.u.upload.old = old;
189 retval = uinput_request_submit(udev, &request);
191 wait_for_completion(&request.done);
192 retval = request.retval;
198 static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
200 struct uinput_device *udev = input_get_drvdata(dev);
201 struct uinput_request request;
204 if (!test_bit(EV_FF, dev->evbit))
208 init_completion(&request.done);
209 request.code = UI_FF_ERASE;
210 request.u.effect_id = effect_id;
212 retval = uinput_request_submit(udev, &request);
214 wait_for_completion(&request.done);
215 retval = request.retval;
221 static void uinput_destroy_device(struct uinput_device *udev)
223 const char *name, *phys;
224 struct input_dev *dev = udev->dev;
225 enum uinput_state old_state = udev->state;
227 udev->state = UIST_NEW_DEVICE;
232 if (old_state == UIST_CREATED) {
233 uinput_flush_requests(udev);
234 input_unregister_device(dev);
236 input_free_device(dev);
244 static int uinput_create_device(struct uinput_device *udev)
246 struct input_dev *dev = udev->dev;
249 if (udev->state != UIST_SETUP_COMPLETE) {
250 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
254 if (udev->ff_effects_max) {
255 error = input_ff_create(dev, udev->ff_effects_max);
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;
266 error = input_register_device(udev->dev);
270 udev->state = UIST_CREATED;
274 fail2: input_ff_destroy(dev);
275 fail1: uinput_destroy_device(udev);
279 static int uinput_open(struct inode *inode, struct file *file)
281 struct uinput_device *newdev;
283 newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
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;
293 file->private_data = newdev;
294 nonseekable_open(inode, file);
299 static int uinput_validate_absbits(struct input_dev *dev)
304 for (cnt = 0; cnt < ABS_CNT; cnt++) {
306 if (!test_bit(cnt, dev->absbit))
309 min = input_abs_get_min(dev, cnt);
310 max = input_abs_get_max(dev, cnt);
312 if ((min != 0 || max != 0) && max <= min) {
314 "%s: invalid abs[%02x] min:%d max:%d\n",
316 input_abs_get_min(dev, cnt),
317 input_abs_get_max(dev, cnt));
322 if (input_abs_get_flat(dev, cnt) >
323 input_abs_get_max(dev, cnt) - input_abs_get_min(dev, cnt)) {
325 "%s: abs_flat #%02x out of range: %d "
328 input_abs_get_flat(dev, cnt),
329 input_abs_get_min(dev, cnt),
330 input_abs_get_max(dev, cnt));
338 static int uinput_allocate_device(struct uinput_device *udev)
340 udev->dev = input_allocate_device();
344 udev->dev->event = uinput_dev_event;
345 input_set_drvdata(udev->dev, udev);
350 static int uinput_setup_device(struct uinput_device *udev, const char __user *buffer, size_t count)
352 struct uinput_user_dev *user_dev;
353 struct input_dev *dev;
357 if (count != sizeof(struct uinput_user_dev))
361 retval = uinput_allocate_device(udev);
368 user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
369 if (IS_ERR(user_dev))
370 return PTR_ERR(user_dev);
372 udev->ff_effects_max = user_dev->ff_effects_max;
374 /* Ensure name is filled in */
375 if (!user_dev->name[0]) {
381 dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
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;
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]);
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);
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);
414 udev->state = UIST_SETUP_COMPLETE;
422 static inline ssize_t uinput_inject_event(struct uinput_device *udev, const char __user *buffer, size_t count)
424 struct input_event ev;
426 if (count < input_event_size())
429 if (input_event_from_user(buffer, &ev))
432 input_event(udev->dev, ev.type, ev.code, ev.value);
434 return input_event_size();
437 static ssize_t uinput_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
439 struct uinput_device *udev = file->private_data;
442 retval = mutex_lock_interruptible(&udev->mutex);
446 retval = udev->state == UIST_CREATED ?
447 uinput_inject_event(udev, buffer, count) :
448 uinput_setup_device(udev, buffer, count);
450 mutex_unlock(&udev->mutex);
455 static bool uinput_fetch_next_event(struct uinput_device *udev,
456 struct input_event *event)
460 spin_lock_irq(&udev->dev->event_lock);
462 have_event = udev->head != udev->tail;
464 *event = udev->buff[udev->tail];
465 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
468 spin_unlock_irq(&udev->dev->event_lock);
473 static ssize_t uinput_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
475 struct uinput_device *udev = file->private_data;
476 struct input_event event;
479 if (udev->state != UIST_CREATED)
482 if (udev->head == udev->tail && (file->f_flags & O_NONBLOCK))
485 retval = wait_event_interruptible(udev->waitq,
486 udev->head != udev->tail || udev->state != UIST_CREATED);
490 retval = mutex_lock_interruptible(&udev->mutex);
494 if (udev->state != UIST_CREATED) {
499 while (retval + input_event_size() <= count &&
500 uinput_fetch_next_event(udev, &event)) {
502 if (input_event_to_user(buffer + retval, &event)) {
507 retval += input_event_size();
511 mutex_unlock(&udev->mutex);
516 static unsigned int uinput_poll(struct file *file, poll_table *wait)
518 struct uinput_device *udev = file->private_data;
520 poll_wait(file, &udev->waitq, wait);
522 if (udev->head != udev->tail)
523 return POLLIN | POLLRDNORM;
528 static int uinput_release(struct inode *inode, struct file *file)
530 struct uinput_device *udev = file->private_data;
532 uinput_destroy_device(udev);
539 struct uinput_ff_upload_compat {
542 struct ff_effect_compat effect;
543 struct ff_effect_compat old;
546 static int uinput_ff_upload_to_user(char __user *buffer,
547 const struct uinput_ff_upload *ff_up)
549 if (INPUT_COMPAT_TEST) {
550 struct uinput_ff_upload_compat ff_up_compat;
552 ff_up_compat.request_id = ff_up->request_id;
553 ff_up_compat.retval = ff_up->retval;
555 * It so happens that the pointer that gives us the trouble
556 * is the last field in the structure. Since we don't support
557 * custom waveforms in uinput anyway we can just copy the whole
558 * thing (to the compat size) and ignore the pointer.
560 memcpy(&ff_up_compat.effect, &ff_up->effect,
561 sizeof(struct ff_effect_compat));
562 memcpy(&ff_up_compat.old, &ff_up->old,
563 sizeof(struct ff_effect_compat));
565 if (copy_to_user(buffer, &ff_up_compat,
566 sizeof(struct uinput_ff_upload_compat)))
569 if (copy_to_user(buffer, ff_up,
570 sizeof(struct uinput_ff_upload)))
577 static int uinput_ff_upload_from_user(const char __user *buffer,
578 struct uinput_ff_upload *ff_up)
580 if (INPUT_COMPAT_TEST) {
581 struct uinput_ff_upload_compat ff_up_compat;
583 if (copy_from_user(&ff_up_compat, buffer,
584 sizeof(struct uinput_ff_upload_compat)))
587 ff_up->request_id = ff_up_compat.request_id;
588 ff_up->retval = ff_up_compat.retval;
589 memcpy(&ff_up->effect, &ff_up_compat.effect,
590 sizeof(struct ff_effect_compat));
591 memcpy(&ff_up->old, &ff_up_compat.old,
592 sizeof(struct ff_effect_compat));
595 if (copy_from_user(ff_up, buffer,
596 sizeof(struct uinput_ff_upload)))
605 static int uinput_ff_upload_to_user(char __user *buffer,
606 const struct uinput_ff_upload *ff_up)
608 if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
614 static int uinput_ff_upload_from_user(const char __user *buffer,
615 struct uinput_ff_upload *ff_up)
617 if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
625 #define uinput_set_bit(_arg, _bit, _max) \
628 if (udev->state == UIST_CREATED) \
630 else if ((_arg) > (_max)) \
632 else set_bit((_arg), udev->dev->_bit); \
636 static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
637 unsigned long arg, void __user *p)
640 struct uinput_device *udev = file->private_data;
641 struct uinput_ff_upload ff_up;
642 struct uinput_ff_erase ff_erase;
643 struct uinput_request *req;
646 retval = mutex_lock_interruptible(&udev->mutex);
651 retval = uinput_allocate_device(udev);
658 retval = uinput_create_device(udev);
662 uinput_destroy_device(udev);
666 retval = uinput_set_bit(arg, evbit, EV_MAX);
670 retval = uinput_set_bit(arg, keybit, KEY_MAX);
674 retval = uinput_set_bit(arg, relbit, REL_MAX);
678 retval = uinput_set_bit(arg, absbit, ABS_MAX);
682 retval = uinput_set_bit(arg, mscbit, MSC_MAX);
686 retval = uinput_set_bit(arg, ledbit, LED_MAX);
690 retval = uinput_set_bit(arg, sndbit, SND_MAX);
694 retval = uinput_set_bit(arg, ffbit, FF_MAX);
698 retval = uinput_set_bit(arg, swbit, SW_MAX);
702 retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
706 if (udev->state == UIST_CREATED) {
711 phys = strndup_user(p, 1024);
713 retval = PTR_ERR(phys);
717 kfree(udev->dev->phys);
718 udev->dev->phys = phys;
721 case UI_BEGIN_FF_UPLOAD:
722 retval = uinput_ff_upload_from_user(p, &ff_up);
726 req = uinput_request_find(udev, ff_up.request_id);
727 if (!req || req->code != UI_FF_UPLOAD || !req->u.upload.effect) {
733 ff_up.effect = *req->u.upload.effect;
734 if (req->u.upload.old)
735 ff_up.old = *req->u.upload.old;
737 memset(&ff_up.old, 0, sizeof(struct ff_effect));
739 retval = uinput_ff_upload_to_user(p, &ff_up);
742 case UI_BEGIN_FF_ERASE:
743 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
748 req = uinput_request_find(udev, ff_erase.request_id);
749 if (!req || req->code != UI_FF_ERASE) {
755 ff_erase.effect_id = req->u.effect_id;
756 if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
763 case UI_END_FF_UPLOAD:
764 retval = uinput_ff_upload_from_user(p, &ff_up);
768 req = uinput_request_find(udev, ff_up.request_id);
769 if (!req || req->code != UI_FF_UPLOAD ||
770 !req->u.upload.effect) {
775 req->retval = ff_up.retval;
776 uinput_request_done(udev, req);
779 case UI_END_FF_ERASE:
780 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
785 req = uinput_request_find(udev, ff_erase.request_id);
786 if (!req || req->code != UI_FF_ERASE) {
791 req->retval = ff_erase.retval;
792 uinput_request_done(udev, req);
800 mutex_unlock(&udev->mutex);
804 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
806 return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
810 static long uinput_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
812 return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
816 static const struct file_operations uinput_fops = {
817 .owner = THIS_MODULE,
819 .release = uinput_release,
821 .write = uinput_write,
823 .unlocked_ioctl = uinput_ioctl,
825 .compat_ioctl = uinput_compat_ioctl,
830 static struct miscdevice uinput_misc = {
831 .fops = &uinput_fops,
832 .minor = UINPUT_MINOR,
835 MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
836 MODULE_ALIAS("devname:" UINPUT_NAME);
838 static int __init uinput_init(void)
840 return misc_register(&uinput_misc);
843 static void __exit uinput_exit(void)
845 misc_deregister(&uinput_misc);
848 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
849 MODULE_DESCRIPTION("User level driver support for input subsystem");
850 MODULE_LICENSE("GPL");
851 MODULE_VERSION("0.3");
853 module_init(uinput_init);
854 module_exit(uinput_exit);