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/*
* $Id: evdev.c,v 1.27 2001/05/28 09:06:44 vojtech Exp $
*
* Copyright (c) 1999-2001 Vojtech Pavlik
*
* Event char devices, giving access to raw input device events.
*
* Sponsored by SuSE
*/
/*
* 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
*
* Should you need to contact me, the author, you can do so either by
* e-mail - mail your message to <vojtech@suse.cz>, or by paper mail:
* Vojtech Pavlik, Ucitelska 1576, Prague 8, 182 00 Czech Republic
*/
#define EVDEV_MINOR_BASE 64
#define EVDEV_MINORS 32
#define EVDEV_BUFFER_SIZE 64
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/input.h>
#include <linux/smp_lock.h>
struct evdev {
int exist;
int open;
int minor;
struct input_handle handle;
wait_queue_head_t wait;
devfs_handle_t devfs;
struct evdev_list *list;
};
struct evdev_list {
struct input_event buffer[EVDEV_BUFFER_SIZE];
int head;
int tail;
struct fasync_struct *fasync;
struct evdev *evdev;
struct evdev_list *next;
};
static struct evdev *evdev_table[EVDEV_MINORS] = { NULL, /* ... */ };
static void evdev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
{
struct evdev *evdev = handle->private;
struct evdev_list *list = evdev->list;
while (list) {
do_gettimeofday(&list->buffer[list->head].time);
list->buffer[list->head].type = type;
list->buffer[list->head].code = code;
list->buffer[list->head].value = value;
list->head = (list->head + 1) & (EVDEV_BUFFER_SIZE - 1);
kill_fasync(&list->fasync, SIGIO, POLL_IN);
list = list->next;
}
wake_up_interruptible(&evdev->wait);
}
static int evdev_fasync(int fd, struct file *file, int on)
{
int retval;
struct evdev_list *list = file->private_data;
retval = fasync_helper(fd, file, on, &list->fasync);
return retval < 0 ? retval : 0;
}
static int evdev_release(struct inode * inode, struct file * file)
{
struct evdev_list *list = file->private_data;
struct evdev_list **listptr;
lock_kernel();
listptr = &list->evdev->list;
evdev_fasync(-1, file, 0);
while (*listptr && (*listptr != list))
listptr = &((*listptr)->next);
*listptr = (*listptr)->next;
if (!--list->evdev->open) {
if (list->evdev->exist) {
input_close_device(&list->evdev->handle);
} else {
input_unregister_minor(list->evdev->devfs);
evdev_table[list->evdev->minor] = NULL;
kfree(list->evdev);
}
}
kfree(list);
unlock_kernel();
return 0;
}
static int evdev_open(struct inode * inode, struct file * file)
{
struct evdev_list *list;
int i = MINOR(inode->i_rdev) - EVDEV_MINOR_BASE;
if (i >= EVDEV_MINORS || !evdev_table[i])
return -ENODEV;
if (!(list = kmalloc(sizeof(struct evdev_list), GFP_KERNEL)))
return -ENOMEM;
memset(list, 0, sizeof(struct evdev_list));
list->evdev = evdev_table[i];
list->next = evdev_table[i]->list;
evdev_table[i]->list = list;
file->private_data = list;
if (!list->evdev->open++)
if (list->evdev->exist)
input_open_device(&list->evdev->handle);
return 0;
}
static ssize_t evdev_write(struct file * file, const char * buffer, size_t count, loff_t *ppos)
{
struct evdev_list *list = file->private_data;
struct input_event event;
int retval = 0;
while (retval < count) {
if (copy_from_user(&event, buffer + retval, sizeof(struct input_event)))
return -EFAULT;
input_event(list->evdev->handle.dev, event.type, event.code, event.value);
retval += sizeof(struct input_event);
}
return retval;
}
static ssize_t evdev_read(struct file * file, char * buffer, size_t count, loff_t *ppos)
{
DECLARE_WAITQUEUE(wait, current);
struct evdev_list *list = file->private_data;
int retval = 0;
if (list->head == list->tail) {
add_wait_queue(&list->evdev->wait, &wait);
current->state = TASK_INTERRUPTIBLE;
while (list->head == list->tail) {
if (!list->evdev->exist) {
retval = -ENODEV;
break;
}
if (file->f_flags & O_NONBLOCK) {
retval = -EAGAIN;
break;
}
if (signal_pending(current)) {
retval = -ERESTARTSYS;
break;
}
schedule();
}
current->state = TASK_RUNNING;
remove_wait_queue(&list->evdev->wait, &wait);
}
if (retval)
return retval;
while (list->head != list->tail && retval + sizeof(struct input_event) <= count) {
if (copy_to_user(buffer + retval, list->buffer + list->tail,
sizeof(struct input_event))) return -EFAULT;
list->tail = (list->tail + 1) & (EVDEV_BUFFER_SIZE - 1);
retval += sizeof(struct input_event);
}
return retval;
}
/* No kernel lock - fine */
static unsigned int evdev_poll(struct file *file, poll_table *wait)
{
struct evdev_list *list = file->private_data;
poll_wait(file, &list->evdev->wait, wait);
if (list->head != list->tail)
return POLLIN | POLLRDNORM;
return 0;
}
static int evdev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
{
struct evdev_list *list = file->private_data;
struct evdev *evdev = list->evdev;
struct input_dev *dev = evdev->handle.dev;
int retval;
switch (cmd) {
case EVIOCGVERSION:
return put_user(EV_VERSION, (int *) arg);
case EVIOCGID:
if ((retval = put_user(dev->idbus, ((short *) arg) + 0))) return retval;
if ((retval = put_user(dev->idvendor, ((short *) arg) + 1))) return retval;
if ((retval = put_user(dev->idproduct, ((short *) arg) + 2))) return retval;
if ((retval = put_user(dev->idversion, ((short *) arg) + 3))) return retval;
return 0;
case EVIOCSFF:
if (dev->upload_effect) {
struct ff_effect effect;
int err;
if (copy_from_user((void*)(&effect), (void*)arg, sizeof(effect))) {
return -EINVAL;
}
err = dev->upload_effect(dev, &effect);
if (put_user(effect.id, &(((struct ff_effect*)arg)->id))) {
return -EINVAL;
}
return err;
}
else return -ENOSYS;
case EVIOCRMFF:
if (dev->erase_effect) {
return dev->erase_effect(dev, (int)arg);
}
else return -ENOSYS;
case EVIOCGEFFECTS:
put_user(dev->ff_effects_max, (int*) arg);
return 0;
default:
if (_IOC_TYPE(cmd) != 'E' || _IOC_DIR(cmd) != _IOC_READ)
return -EINVAL;
if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) {
long *bits;
int len;
switch (_IOC_NR(cmd) & EV_MAX) {
case 0: bits = dev->evbit; len = EV_MAX; break;
case EV_KEY: bits = dev->keybit; len = KEY_MAX; break;
case EV_REL: bits = dev->relbit; len = REL_MAX; break;
case EV_ABS: bits = dev->absbit; len = ABS_MAX; break;
case EV_LED: bits = dev->ledbit; len = LED_MAX; break;
case EV_SND: bits = dev->sndbit; len = SND_MAX; break;
case EV_FF: bits = dev->ffbit; len = FF_MAX; break;
default: return -EINVAL;
}
len = NBITS(len) * sizeof(long);
if (len > _IOC_SIZE(cmd)) {
printk(KERN_WARNING "evdev.c: Truncating bitfield length from %d to %d\n",
len, _IOC_SIZE(cmd));
len = _IOC_SIZE(cmd);
}
return copy_to_user((char *) arg, bits, len) ? -EFAULT : len;
}
if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) {
int len;
if (!dev->name) return 0;
len = strlen(dev->name) + 1;
if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
return copy_to_user((char *) arg, dev->name, len) ? -EFAULT : len;
}
if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) {
int t = _IOC_NR(cmd) & ABS_MAX;
if ((retval = put_user(dev->abs[t], ((int *) arg) + 0))) return retval;
if ((retval = put_user(dev->absmin[t], ((int *) arg) + 1))) return retval;
if ((retval = put_user(dev->absmax[t], ((int *) arg) + 2))) return retval;
if ((retval = put_user(dev->absfuzz[t], ((int *) arg) + 3))) return retval;
if ((retval = put_user(dev->absflat[t], ((int *) arg) + 4))) return retval;
return 0;
}
}
return -EINVAL;
}
static struct file_operations evdev_fops = {
owner: THIS_MODULE,
read: evdev_read,
write: evdev_write,
poll: evdev_poll,
open: evdev_open,
release: evdev_release,
ioctl: evdev_ioctl,
fasync: evdev_fasync,
};
static struct input_handle *evdev_connect(struct input_handler *handler, struct input_dev *dev)
{
struct evdev *evdev;
int minor;
for (minor = 0; minor < EVDEV_MINORS && evdev_table[minor]; minor++);
if (minor == EVDEV_MINORS) {
printk(KERN_ERR "evdev: no more free evdev devices\n");
return NULL;
}
if (!(evdev = kmalloc(sizeof(struct evdev), GFP_KERNEL)))
return NULL;
memset(evdev, 0, sizeof(struct evdev));
init_waitqueue_head(&evdev->wait);
evdev->minor = minor;
evdev_table[minor] = evdev;
evdev->handle.dev = dev;
evdev->handle.handler = handler;
evdev->handle.private = evdev;
evdev->exist = 1;
evdev->devfs = input_register_minor("event%d", minor, EVDEV_MINOR_BASE);
// printk(KERN_INFO "event%d: Event device for input%d\n", minor, dev->number);
return &evdev->handle;
}
static void evdev_disconnect(struct input_handle *handle)
{
struct evdev *evdev = handle->private;
evdev->exist = 0;
if (evdev->open) {
input_close_device(handle);
wake_up_interruptible(&evdev->wait);
} else {
input_unregister_minor(evdev->devfs);
evdev_table[evdev->minor] = NULL;
kfree(evdev);
}
}
static struct input_handler evdev_handler = {
event: evdev_event,
connect: evdev_connect,
disconnect: evdev_disconnect,
fops: &evdev_fops,
minor: EVDEV_MINOR_BASE,
};
static int __init evdev_init(void)
{
input_register_handler(&evdev_handler);
return 0;
}
static void __exit evdev_exit(void)
{
input_unregister_handler(&evdev_handler);
}
module_init(evdev_init);
module_exit(evdev_exit);
MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
MODULE_DESCRIPTION("Event character device driver");
MODULE_LICENSE("GPL");
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