/*
* mpc8xx_wdt.c - MPC8xx watchdog userspace interface
*
* Author: Florian Schirmer <jolt@tuxbox.org>
*
* 2002 (c) Florian Schirmer <jolt@tuxbox.org> This file is licensed under
* the terms of the GNU General Public License version 2. This program
* is licensed "as is" without any warranty of any kind, whether express
* or implied.
*/
#include <linux/config.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/watchdog.h>
#include <asm/8xx_immap.h>
#include <asm/uaccess.h>
#include <syslib/m8xx_wdt.h>
static unsigned long wdt_opened;
static int wdt_status;
static void mpc8xx_wdt_handler_disable(void)
{
volatile immap_t *imap = (volatile immap_t *)IMAP_ADDR;
imap->im_sit.sit_piscr &= ~(PISCR_PIE | PISCR_PTE);
printk(KERN_NOTICE "mpc8xx_wdt: keep-alive handler deactivated\n");
}
static void mpc8xx_wdt_handler_enable(void)
{
volatile immap_t *imap = (volatile immap_t *)IMAP_ADDR;
imap->im_sit.sit_piscr |= PISCR_PIE | PISCR_PTE;
printk(KERN_NOTICE "mpc8xx_wdt: keep-alive handler activated\n");
}
static int mpc8xx_wdt_open(struct inode *inode, struct file *file)
{
if (test_and_set_bit(0, &wdt_opened))
return -EBUSY;
m8xx_wdt_reset();
mpc8xx_wdt_handler_disable();
return 0;
}
static int mpc8xx_wdt_release(struct inode *inode, struct file *file)
{
m8xx_wdt_reset();
#if !defined(CONFIG_WATCHDOG_NOWAYOUT)
mpc8xx_wdt_handler_enable();
#endif
clear_bit(0, &wdt_opened);
return 0;
}
static ssize_t mpc8xx_wdt_write(struct file *file, const char *data, size_t len,
loff_t * ppos)
{
if (ppos != &file->f_pos)
return -ESPIPE;
if (len)
m8xx_wdt_reset();
return len;
}
static int mpc8xx_wdt_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
int timeout;
static struct watchdog_info info = {
.options = WDIOF_KEEPALIVEPING,
.firmware_version = 0,
.identity = "MPC8xx watchdog",
};
switch (cmd) {
case WDIOC_GETSUPPORT:
if (copy_to_user((void *)arg, &info, sizeof(info)))
return -EFAULT;
break;
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
if (put_user(wdt_status, (int *)arg))
return -EFAULT;
wdt_status &= ~WDIOF_KEEPALIVEPING;
break;
case WDIOC_GETTEMP:
return -EOPNOTSUPP;
case WDIOC_SETOPTIONS:
return -EOPNOTSUPP;
case WDIOC_KEEPALIVE:
m8xx_wdt_reset();
wdt_status |= WDIOF_KEEPALIVEPING;
break;
case WDIOC_SETTIMEOUT:
return -EOPNOTSUPP;
case WDIOC_GETTIMEOUT:
timeout = m8xx_wdt_get_timeout();
if (put_user(timeout, (int *)arg))
return -EFAULT;
break;
default:
return -ENOIOCTLCMD;
}
return 0;
}
static struct file_operations mpc8xx_wdt_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = mpc8xx_wdt_write,
.ioctl = mpc8xx_wdt_ioctl,
.open = mpc8xx_wdt_open,
.release = mpc8xx_wdt_release,
};
static struct miscdevice mpc8xx_wdt_miscdev = {
.minor = WATCHDOG_MINOR,
.name = "watchdog",
.fops = &mpc8xx_wdt_fops,
};
static int __init mpc8xx_wdt_init(void)
{
return misc_register(&mpc8xx_wdt_miscdev);
}
static void __exit mpc8xx_wdt_exit(void)
{
misc_deregister(&mpc8xx_wdt_miscdev);
m8xx_wdt_reset();
mpc8xx_wdt_handler_enable();
}
module_init(mpc8xx_wdt_init);
module_exit(mpc8xx_wdt_exit);
MODULE_AUTHOR("Florian Schirmer <jolt@tuxbox.org>");
MODULE_DESCRIPTION("MPC8xx watchdog driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
