- 根目录:
- drivers
- input
- misc
- uinput.c
/*
* User level driver support for input subsystem
*
* Heavily based on evdev.c by Vojtech Pavlik
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Author: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
*
* Changes/Revisions:
* 0.3 09/04/2006 (Anssi Hannula <anssi.hannula@gmail.com>)
* - updated ff support for the changes in kernel interface
* - added MODULE_VERSION
* 0.2 16/10/2004 (Micah Dowty <micah@navi.cx>)
* - added force feedback support
* - added UI_SET_PHYS
* 0.1 20/06/2002
* - first public version
*/
#include <linux/poll.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <linux/uinput.h>
#include <linux/input/mt.h>
#include "../input-compat.h"
static int uinput_dev_event(struct input_dev *dev,
unsigned int type, unsigned int code, int value)
{
struct uinput_device *udev = input_get_drvdata(dev);
udev->buff[udev->head].type = type;
udev->buff[udev->head].code = code;
udev->buff[udev->head].value = value;
do_gettimeofday(&udev->buff[udev->head].time);
udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
wake_up_interruptible(&udev->waitq);
return 0;
}
/* Atomically allocate an ID for the given request. Returns 0 on success. */
static bool uinput_request_alloc_id(struct uinput_device *udev,
struct uinput_request *request)
{
unsigned int id;
bool reserved = false;
spin_lock(&udev->requests_lock);
for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
if (!udev->requests[id]) {
request->id = id;
udev->requests[id] = request;
reserved = true;
break;
}
}
spin_unlock(&udev->requests_lock);
return reserved;
}
static struct uinput_request *uinput_request_find(struct uinput_device *udev,
unsigned int id)
{
/* Find an input request, by ID. Returns NULL if the ID isn't valid. */
if (id >= UINPUT_NUM_REQUESTS)
return NULL;
return udev->requests[id];
}
static int uinput_request_reserve_slot(struct uinput_device *udev,
struct uinput_request *request)
{
/* Allocate slot. If none are available right away, wait. */
return wait_event_interruptible(udev->requests_waitq,
uinput_request_alloc_id(udev, request));
}
static void uinput_request_done(struct uinput_device *udev,
struct uinput_request *request)
{
/* Mark slot as available */
udev->requests[request->id] = NULL;
wake_up(&udev->requests_waitq);
complete(&request->done);
}
static int uinput_request_send(struct uinput_device *udev,
struct uinput_request *request)
{
int retval;
retval = mutex_lock_interruptible(&udev->mutex);
if (retval)
return retval;
if (udev->state != UIST_CREATED) {
retval = -ENODEV;
goto out;
}
init_completion(&request->done);
/*
* Tell our userspace application about this new request
* by queueing an input event.
*/
uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
out:
mutex_unlock(&udev->mutex);
return retval;
}
static int uinput_request_submit(struct uinput_device *udev,
struct uinput_request *request)
{
int error;
error = uinput_request_reserve_slot(udev, request);
if (error)
return error;
error = uinput_request_send(udev, request);
if (error) {
uinput_request_done(udev, request);
return error;
}
wait_for_completion(&request->done);
return request->retval;
}
/*
* Fail all outstanding requests so handlers don't wait for the userspace
* to finish processing them.
*/
static void uinput_flush_requests(struct uinput_device *udev)
{
struct uinput_request *request;
int i;
spin_lock(&udev->requests_lock);
for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
request = udev->requests[i];
if (request) {
request->retval = -ENODEV;
uinput_request_done(udev, request);
}
}
spin_unlock(&udev->requests_lock);
}
static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
{
uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
}
static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
{
uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
}
static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
{
return uinput_dev_event(dev, EV_FF, effect_id, value);
}
static int uinput_dev_upload_effect(struct input_dev *dev,
struct ff_effect *effect,
struct ff_effect *old)
{
struct uinput_device *udev = input_get_drvdata(dev);
struct uinput_request request;
/*
* uinput driver does not currently support periodic effects with
* custom waveform since it does not have a way to pass buffer of
* samples (custom_data) to userspace. If ever there is a device
* supporting custom waveforms we would need to define an additional
* ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
*/
if (effect->type == FF_PERIODIC &&
effect->u.periodic.waveform == FF_CUSTOM)
return -EINVAL;
request.code = UI_FF_UPLOAD;
request.u.upload.effect = effect;
request.u.upload.old = old;
return uinput_request_submit(udev, &request);
}
static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
{
struct uinput_device *udev = input_get_drvdata(dev);
struct uinput_request request;
if (!test_bit(EV_FF, dev->evbit))
return -ENOSYS;
request.code = UI_FF_ERASE;
request.u.effect_id = effect_id;
return uinput_request_submit(udev, &request);
}
static void uinput_destroy_device(struct uinput_device *udev)
{
const char *name, *phys;
struct input_dev *dev = udev->dev;
enum uinput_state old_state = udev->state;
udev->state = UIST_NEW_DEVICE;
if (dev) {
name = dev->name;
phys = dev->phys;
if (old_state == UIST_CREATED) {
uinput_flush_requests(udev);
input_unregister_device(dev);
} else {
input_free_device(dev);
}
kfree(name);
kfree(phys);
udev->dev = NULL;
}
}
static int uinput_create_device(struct uinput_device *udev)
{
struct input_dev *dev = udev->dev;
int error;
if (udev->state != UIST_SETUP_COMPLETE) {
printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
return -EINVAL;
}
if (udev->ff_effects_max) {
error = input_ff_create(dev, udev->ff_effects_max);
if (error)
goto fail1;
dev->ff->upload = uinput_dev_upload_effect;
dev->ff->erase = uinput_dev_erase_effect;
dev->ff->playback = uinput_dev_playback;
dev->ff->set_gain = uinput_dev_set_gain;
dev->ff->set_autocenter = uinput_dev_set_autocenter;
}
error = input_register_device(udev->dev);
if (error)
goto fail2;
udev->state = UIST_CREATED;
return 0;
fail2: input_ff_destroy(dev);
fail1: uinput_destroy_device(udev);
return error;
}
static int uinput_open(struct inode *inode, struct file *file)
{
struct uinput_device *newdev;
newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
if (!newdev)
return -ENOMEM;
mutex_init(&newdev->mutex);
spin_lock_init(&newdev->requests_lock);
init_waitqueue_head(&newdev->requests_waitq);
init_waitqueue_head(&newdev->waitq);
newdev->state = UIST_NEW_DEVICE;
file->private_data = newdev;
nonseekable_open(inode, file);
return 0;
}
static int uinput_validate_absbits(struct input_dev *dev)
{
unsigned int cnt;
int retval = 0;
for (cnt = 0; cnt < ABS_CNT; cnt++) {
int min, max;
if (!test_bit(cnt, dev->absbit))
continue;
min = input_abs_get_min(dev, cnt);
max = input_abs_get_max(dev, cnt);
if ((min != 0 || max != 0) && max <= min) {
printk(KERN_DEBUG
"%s: invalid abs[%02x] min:%d max:%d\n",
UINPUT_NAME, cnt,
input_abs_get_min(dev, cnt),
input_abs_get_max(dev, cnt));
retval = -EINVAL;
break;
}
if (input_abs_get_flat(dev, cnt) >
input_abs_get_max(dev, cnt) - input_abs_get_min(dev, cnt)) {
printk(KERN_DEBUG
"%s: abs_flat #%02x out of range: %d "
"(min:%d/max:%d)\n",
UINPUT_NAME, cnt,
input_abs_get_flat(dev, cnt),
input_abs_get_min(dev, cnt),
input_abs_get_max(dev, cnt));
retval = -EINVAL;
break;
}
}
return retval;
}
static int uinput_allocate_device(struct uinput_device *udev)
{
udev->dev = input_allocate_device();
if (!udev->dev)
return -ENOMEM;
udev->dev->event = uinput_dev_event;
input_set_drvdata(udev->dev, udev);
return 0;
}
static int uinput_setup_device(struct uinput_device *udev,
const char __user *buffer, size_t count)
{
struct uinput_user_dev *user_dev;
struct input_dev *dev;
int i;
int retval;
if (count != sizeof(struct uinput_user_dev))
return -EINVAL;
if (!udev->dev) {
retval = uinput_allocate_device(udev);
if (retval)
return retval;
}
dev = udev->dev;
user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
if (IS_ERR(user_dev))
return PTR_ERR(user_dev);
udev->ff_effects_max = user_dev->ff_effects_max;
/* Ensure name is filled in */
if (!user_dev->name[0]) {
retval = -EINVAL;
goto exit;
}
kfree(dev->name);
dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
GFP_KERNEL);
if (!dev->name) {
retval = -ENOMEM;
goto exit;
}
dev->id.bustype = user_dev->id.bustype;
dev->id.vendor = user_dev->id.vendor;
dev->id.product = user_dev->id.product;
dev->id.version = user_dev->id.version;
for (i = 0; i < ABS_CNT; i++) {
input_abs_set_max(dev, i, user_dev->absmax[i]);
input_abs_set_min(dev, i, user_dev->absmin[i]);
input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
input_abs_set_flat(dev, i, user_dev->absflat[i]);
}
/* check if absmin/absmax/absfuzz/absflat are filled as
* told in Documentation/input/input-programming.txt */
if (test_bit(EV_ABS, dev->evbit)) {
retval = uinput_validate_absbits(dev);
if (retval < 0)
goto exit;
if (test_bit(ABS_MT_SLOT, dev->absbit)) {
int nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
input_mt_init_slots(dev, nslot, 0);
} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
input_set_events_per_packet(dev, 60);
}
}
udev->state = UIST_SETUP_COMPLETE;
retval = count;
exit:
kfree(user_dev);
return retval;
}
static ssize_t uinput_inject_event(struct uinput_device *udev,
const char __user *buffer, size_t count)
{
struct input_event ev;
if (count < input_event_size())
return -EINVAL;
if (input_event_from_user(buffer, &ev))
return -EFAULT;
input_event(udev->dev, ev.type, ev.code, ev.value);
return input_event_size();
}
static ssize_t uinput_write(struct file *file, const char __user *buffer,
size_t count, loff_t *ppos)
{
struct uinput_device *udev = file->private_data;
int retval;
if (count == 0)
return 0;
retval = mutex_lock_interruptible(&udev->mutex);
if (retval)
return retval;
retval = udev->state == UIST_CREATED ?
uinput_inject_event(udev, buffer, count) :
uinput_setup_device(udev, buffer, count);
mutex_unlock(&udev->mutex);
return retval;
}
static bool uinput_fetch_next_event(struct uinput_device *udev,
struct input_event *event)
{
bool have_event;
spin_lock_irq(&udev->dev->event_lock);
have_event = udev->head != udev->tail;
if (have_event) {
*event = udev->buff[udev->tail];
udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
}
spin_unlock_irq(&udev->dev->event_lock);
return have_event;
}
static ssize_t uinput_events_to_user(struct uinput_device *udev,
char __user *buffer, size_t count)
{
struct input_event event;
size_t read = 0;
while (read + input_event_size() <= count &&
uinput_fetch_next_event(udev, &event)) {
if (input_event_to_user(buffer + read, &event))
return -EFAULT;
read += input_event_size();
}
return read;
}
static ssize_t uinput_read(struct file *file, char __user *buffer,
size_t count, loff_t *ppos)
{
struct uinput_device *udev = file->private_data;
ssize_t retval;
if (count != 0 && count < input_event_size())
return -EINVAL;
do {
retval = mutex_lock_interruptible(&udev->mutex);
if (retval)
return retval;
if (udev->state != UIST_CREATED)
retval = -ENODEV;
else if (udev->head == udev->tail &&
(file->f_flags & O_NONBLOCK))
retval = -EAGAIN;
else
retval = uinput_events_to_user(udev, buffer, count);
mutex_unlock(&udev->mutex);
if (retval || count == 0)
break;
if (!(file->f_flags & O_NONBLOCK))
retval = wait_event_interruptible(udev->waitq,
udev->head != udev->tail ||
udev->state != UIST_CREATED);
} while (retval == 0);
return retval;
}
static unsigned int uinput_poll(struct file *file, poll_table *wait)
{
struct uinput_device *udev = file->private_data;
poll_wait(file, &udev->waitq, wait);
if (udev->head != udev->tail)
return POLLIN | POLLRDNORM;
return 0;
}
static int uinput_release(struct inode *inode, struct file *file)
{
struct uinput_device *udev = file->private_data;
uinput_destroy_device(udev);
kfree(udev);
return 0;
}
#ifdef CONFIG_COMPAT
struct uinput_ff_upload_compat {
__u32 request_id;
__s32 retval;
struct ff_effect_compat effect;
struct ff_effect_compat old;
};
static int uinput_ff_upload_to_user(char __user *buffer,
const struct uinput_ff_upload *ff_up)
{
if (INPUT_COMPAT_TEST) {
struct uinput_ff_upload_compat ff_up_compat;
ff_up_compat.request_id = ff_up->request_id;
ff_up_compat.retval = ff_up->retval;
/*
* It so happens that the pointer that gives us the trouble
* is the last field in the structure. Since we don't support
* custom waveforms in uinput anyway we can just copy the whole
* thing (to the compat size) and ignore the pointer.
*/
memcpy(&ff_up_compat.effect, &ff_up->effect,
sizeof(struct ff_effect_compat));
memcpy(&ff_up_compat.old, &ff_up->old,
sizeof(struct ff_effect_compat));
if (copy_to_user(buffer, &ff_up_compat,
sizeof(struct uinput_ff_upload_compat)))
return -EFAULT;
} else {
if (copy_to_user(buffer, ff_up,
sizeof(struct uinput_ff_upload)))
return -EFAULT;
}
return 0;
}
static int uinput_ff_upload_from_user(const char __user *buffer,
struct uinput_ff_upload *ff_up)
{
if (INPUT_COMPAT_TEST) {
struct uinput_ff_upload_compat ff_up_compat;
if (copy_from_user(&ff_up_compat, buffer,
sizeof(struct uinput_ff_upload_compat)))
return -EFAULT;
ff_up->request_id = ff_up_compat.request_id;
ff_up->retval = ff_up_compat.retval;
memcpy(&ff_up->effect, &ff_up_compat.effect,
sizeof(struct ff_effect_compat));
memcpy(&ff_up->old, &ff_up_compat.old,
sizeof(struct ff_effect_compat));
} else {
if (copy_from_user(ff_up, buffer,
sizeof(struct uinput_ff_upload)))
return -EFAULT;
}
return 0;
}
#else
static int uinput_ff_upload_to_user(char __user *buffer,
const struct uinput_ff_upload *ff_up)
{
if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
return -EFAULT;
return 0;
}
static int uinput_ff_upload_from_user(const char __user *buffer,
struct uinput_ff_upload *ff_up)
{
if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
return -EFAULT;
return 0;
}
#endif
#define uinput_set_bit(_arg, _bit, _max) \
({ \
int __ret = 0; \
if (udev->state == UIST_CREATED) \
__ret = -EINVAL; \
else if ((_arg) > (_max)) \
__ret = -EINVAL; \
else set_bit((_arg), udev->dev->_bit); \
__ret; \
})
static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
unsigned long arg, void __user *p)
{
int retval;
struct uinput_device *udev = file->private_data;
struct uinput_ff_upload ff_up;
struct uinput_ff_erase ff_erase;
struct uinput_request *req;
char *phys;
retval = mutex_lock_interruptible(&udev->mutex);
if (retval)
return retval;
if (!udev->dev) {
retval = uinput_allocate_device(udev);
if (retval)
goto out;
}
switch (cmd) {
case UI_DEV_CREATE:
retval = uinput_create_device(udev);
break;
case UI_DEV_DESTROY:
uinput_destroy_device(udev);
break;
case UI_SET_EVBIT:
retval = uinput_set_bit(arg, evbit, EV_MAX);
break;
case UI_SET_KEYBIT:
retval = uinput_set_bit(arg, keybit, KEY_MAX);
break;
case UI_SET_RELBIT:
retval = uinput_set_bit(arg, relbit, REL_MAX);
break;
case UI_SET_ABSBIT:
retval = uinput_set_bit(arg, absbit, ABS_MAX);
break;
case UI_SET_MSCBIT:
retval = uinput_set_bit(arg, mscbit, MSC_MAX);
break;
case UI_SET_LEDBIT:
retval = uinput_set_bit(arg, ledbit, LED_MAX);
break;
case UI_SET_SNDBIT:
retval = uinput_set_bit(arg, sndbit, SND_MAX);
break;
case UI_SET_FFBIT:
retval = uinput_set_bit(arg, ffbit, FF_MAX);
break;
case UI_SET_SWBIT:
retval = uinput_set_bit(arg, swbit, SW_MAX);
break;
case UI_SET_PROPBIT:
retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
break;
case UI_SET_PHYS:
if (udev->state == UIST_CREATED) {
retval = -EINVAL;
goto out;
}
phys = strndup_user(p, 1024);
if (IS_ERR(phys)) {
retval = PTR_ERR(phys);
goto out;
}
kfree(udev->dev->phys);
udev->dev->phys = phys;
break;
case UI_BEGIN_FF_UPLOAD:
retval = uinput_ff_upload_from_user(p, &ff_up);
if (retval)
break;
req = uinput_request_find(udev, ff_up.request_id);
if (!req || req->code != UI_FF_UPLOAD ||
!req->u.upload.effect) {
retval = -EINVAL;
break;
}
ff_up.retval = 0;
ff_up.effect = *req->u.upload.effect;
if (req->u.upload.old)
ff_up.old = *req->u.upload.old;
else
memset(&ff_up.old, 0, sizeof(struct ff_effect));
retval = uinput_ff_upload_to_user(p, &ff_up);
break;
case UI_BEGIN_FF_ERASE:
if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
retval = -EFAULT;
break;
}
req = uinput_request_find(udev, ff_erase.request_id);
if (!req || req->code != UI_FF_ERASE) {
retval = -EINVAL;
break;
}
ff_erase.retval = 0;
ff_erase.effect_id = req->u.effect_id;
if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
retval = -EFAULT;
break;
}
break;
case UI_END_FF_UPLOAD:
retval = uinput_ff_upload_from_user(p, &ff_up);
if (retval)
break;
req = uinput_request_find(udev, ff_up.request_id);
if (!req || req->code != UI_FF_UPLOAD ||
!req->u.upload.effect) {
retval = -EINVAL;
break;
}
req->retval = ff_up.retval;
uinput_request_done(udev, req);
break;
case UI_END_FF_ERASE:
if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
retval = -EFAULT;
break;
}
req = uinput_request_find(udev, ff_erase.request_id);
if (!req || req->code != UI_FF_ERASE) {
retval = -EINVAL;
break;
}
req->retval = ff_erase.retval;
uinput_request_done(udev, req);
break;
default:
retval = -EINVAL;
}
out:
mutex_unlock(&udev->mutex);
return retval;
}
static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
}
#ifdef CONFIG_COMPAT
static long uinput_compat_ioctl(struct file *file,
unsigned int cmd, unsigned long arg)
{
return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
}
#endif
static const struct file_operations uinput_fops = {
.owner = THIS_MODULE,
.open = uinput_open,
.release = uinput_release,
.read = uinput_read,
.write = uinput_write,
.poll = uinput_poll,
.unlocked_ioctl = uinput_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = uinput_compat_ioctl,
#endif
.llseek = no_llseek,
};
static struct miscdevice uinput_misc = {
.fops = &uinput_fops,
.minor = UINPUT_MINOR,
.name = UINPUT_NAME,
};
MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
MODULE_ALIAS("devname:" UINPUT_NAME);
static int __init uinput_init(void)
{
return misc_register(&uinput_misc);
}
static void __exit uinput_exit(void)
{
misc_deregister(&uinput_misc);
}
MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
MODULE_DESCRIPTION("User level driver support for input subsystem");
MODULE_LICENSE("GPL");
MODULE_VERSION("0.3");
module_init(uinput_init);
module_exit(uinput_exit);