![Wim Van Sebroeck](/assets/img/avatar_default.png)
All watchdog device drivers are VFSs (Virtual File Systems). We thus return a nonseekable_open(inode, file) when we open the VFS. Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
170 lines
3.6 KiB
C
170 lines
3.6 KiB
C
/*
|
|
* 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/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 <asm/io.h>
|
|
#include <syslib/m8xx_wdt.h>
|
|
|
|
static unsigned long wdt_opened;
|
|
static int wdt_status;
|
|
|
|
static void mpc8xx_wdt_handler_disable(void)
|
|
{
|
|
volatile uint __iomem *piscr;
|
|
piscr = (uint *)&((immap_t*)IMAP_ADDR)->im_sit.sit_piscr;
|
|
|
|
if (!m8xx_has_internal_rtc)
|
|
m8xx_wdt_stop_timer();
|
|
else
|
|
out_be32(piscr, in_be32(piscr) & ~(PISCR_PIE | PISCR_PTE));
|
|
|
|
printk(KERN_NOTICE "mpc8xx_wdt: keep-alive handler deactivated\n");
|
|
}
|
|
|
|
static void mpc8xx_wdt_handler_enable(void)
|
|
{
|
|
volatile uint __iomem *piscr;
|
|
piscr = (uint *)&((immap_t*)IMAP_ADDR)->im_sit.sit_piscr;
|
|
|
|
if (!m8xx_has_internal_rtc)
|
|
m8xx_wdt_install_timer();
|
|
else
|
|
out_be32(piscr, in_be32(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 nonseekable_open(inode, file);
|
|
}
|
|
|
|
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 (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 -ENOTTY;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const 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);
|