/*
* Copyright (C) 2005 Jakub Jermar
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <console/chardev.h>
#include <putchar.h>
#include <synch/waitq.h>
#include <synch/spinlock.h>
/** Initialize character device.
*
* @param chardev Character device.
* @param op Implementation of character device operations.
*/
void chardev_initialize(char *name,chardev_t *chardev,
chardev_operations_t *op)
{
chardev->name = name;
waitq_initialize(&chardev->wq);
spinlock_initialize(&chardev->lock, "chardev");
chardev->counter = 0;
chardev->index = 0;
chardev->op = op;
}
/** Push character read from input character device.
*
* @param chardev Character device.
* @param ch Character being pushed.
*/
void chardev_push_character(chardev_t *chardev, __u8 ch)
{
spinlock_lock(&chardev->lock);
chardev->counter++;
if (chardev->counter == CHARDEV_BUFLEN - 1) {
/* buffer full => disable device interrupt */
chardev->op->suspend(chardev);
}
chardev->buffer[chardev->index++] = ch;
chardev->index = chardev->index % CHARDEV_BUFLEN; /* index modulo size of buffer */
waitq_wakeup(&chardev->wq, WAKEUP_FIRST);
spinlock_unlock(&chardev->lock);
}