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/*
* Event char devices, giving access to raw input device events.
*
* Copyright (c) 1999-2002 Vojtech Pavlik
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*/
#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/major.h>
#include <linux/smp_lock.h>
#include <linux/device.h>
#include <linux/compat.h>
struct evdev {
int exist;
int open;
int minor;
char name[16];
struct input_handle handle;
wait_queue_head_t wait;
struct evdev_list *grab;
struct list_head list;
};
struct evdev_list {
struct input_event buffer[EVDEV_BUFFER_SIZE];
int head;
int tail;
struct fasync_struct *fasync;
struct evdev *evdev;
struct list_head node;
};
static struct evdev *evdev_table[EVDEV_MINORS];
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;
if (evdev->grab) {
list = evdev->grab;
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);
} else
list_for_each_entry(list, &evdev->list, node) {
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);
}
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_flush(struct file * file)
{
struct evdev_list *list = file->private_data;
if (!list->evdev->exist) return -ENODEV;
return input_flush_device(&list->evdev->handle, file);
}
static void evdev_free(struct evdev *evdev)
{
evdev_table[evdev->minor] = NULL;
kfree(evdev);
}
static int evdev_release(struct inode * inode, struct file * file)
{
struct evdev_list *list = file->private_data;
if (list->evdev->grab == list) {
input_release_device(&list->evdev->handle);
list->evdev->grab = NULL;
}
evdev_fasync(-1, file, 0);
list_del(&list->node);
if (!--list->evdev->open) {
if (list->evdev->exist)
input_close_device(&list->evdev->handle);
else
evdev_free(list->evdev);
}
kfree(list);
return 0;
}
static int evdev_open(struct inode * inode, struct file * file)
{
struct evdev_list *list;
int i = iminor(inode) - EVDEV_MINOR_BASE;
int accept_err;
if (i >= EVDEV_MINORS || !evdev_table[i] || !evdev_table[i]->exist)
return -ENODEV;
if ((accept_err = input_accept_process(&(evdev_table[i]->handle), file)))
return accept_err;
if (!(list = kzalloc(sizeof(struct evdev_list), GFP_KERNEL)))
return -ENOMEM;
list->evdev = evdev_table[i];
list_add_tail(&list->node, &evdev_table[i]->list);
file->private_data = list;
if (!list->evdev->open++)
if (list->evdev->exist)
input_open_device(&list->evdev->handle);
return 0;
}
#ifdef CONFIG_COMPAT
struct input_event_compat {
struct compat_timeval time;
__u16 type;
__u16 code;
__s32 value;
};
/* Note to the author of this code: did it ever occur to
you why the ifdefs are needed? Think about it again. -AK */
#ifdef CONFIG_X86_64
# define COMPAT_TEST is_compat_task()
#elif defined(CONFIG_IA64)
# define COMPAT_TEST IS_IA32_PROCESS(task_pt_regs(current))
#elif defined(CONFIG_S390)
# define COMPAT_TEST test_thread_flag(TIF_31BIT)
#elif defined(CONFIG_MIPS)
# define COMPAT_TEST (current->thread.mflags & MF_32BIT_ADDR)
#else
# define COMPAT_TEST test_thread_flag(TIF_32BIT)
#endif
static inline size_t evdev_event_size(void)
{
return COMPAT_TEST ?
sizeof(struct input_event_compat) : sizeof(struct input_event);
}
static int evdev_event_from_user(const char __user *buffer, struct input_event *event)
{
if (COMPAT_TEST) {
struct input_event_compat compat_event;
if (copy_from_user(&compat_event, buffer, sizeof(struct input_event_compat)))
return -EFAULT;
event->time.tv_sec = compat_event.time.tv_sec;
event->time.tv_usec = compat_event.time.tv_usec;
event->type = compat_event.type;
event->code = compat_event.code;
event->value = compat_event.value;
} else
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