mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 01:10:04 +00:00
![Wim Van Sebroeck](/assets/img/avatar_default.png)
Make sure that when the WDIOF_MAGICCLOSE flag is set we also support the magic-close feature... Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
226 lines
5.1 KiB
C
226 lines
5.1 KiB
C
/*
|
|
* SBC EPX C3 0.1 A Hardware Watchdog Device for the Winsystems EPX-C3
|
|
* single board computer
|
|
*
|
|
* (c) Copyright 2006 Calin A. Culianu <calin@ajvar.org>, All Rights
|
|
* Reserved.
|
|
*
|
|
* 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.
|
|
*
|
|
* based on softdog.c by Alan Cox <alan@lxorguk.ukuu.org.uk>
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/moduleparam.h>
|
|
#include <linux/types.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/miscdevice.h>
|
|
#include <linux/watchdog.h>
|
|
#include <linux/notifier.h>
|
|
#include <linux/reboot.h>
|
|
#include <linux/init.h>
|
|
#include <linux/ioport.h>
|
|
#include <linux/uaccess.h>
|
|
#include <linux/io.h>
|
|
|
|
#define PFX "epx_c3: "
|
|
static int epx_c3_alive;
|
|
|
|
#define WATCHDOG_TIMEOUT 1 /* 1 sec default timeout */
|
|
|
|
static int nowayout = WATCHDOG_NOWAYOUT;
|
|
module_param(nowayout, int, 0);
|
|
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
|
|
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
|
|
|
|
#define EPXC3_WATCHDOG_CTL_REG 0x1ee /* write 1 to enable, 0 to disable */
|
|
#define EPXC3_WATCHDOG_PET_REG 0x1ef /* write anything to pet once enabled */
|
|
|
|
static void epx_c3_start(void)
|
|
{
|
|
outb(1, EPXC3_WATCHDOG_CTL_REG);
|
|
}
|
|
|
|
static void epx_c3_stop(void)
|
|
{
|
|
|
|
outb(0, EPXC3_WATCHDOG_CTL_REG);
|
|
|
|
printk(KERN_INFO PFX "Stopped watchdog timer.\n");
|
|
}
|
|
|
|
static void epx_c3_pet(void)
|
|
{
|
|
outb(1, EPXC3_WATCHDOG_PET_REG);
|
|
}
|
|
|
|
/*
|
|
* Allow only one person to hold it open
|
|
*/
|
|
static int epx_c3_open(struct inode *inode, struct file *file)
|
|
{
|
|
if (epx_c3_alive)
|
|
return -EBUSY;
|
|
|
|
if (nowayout)
|
|
__module_get(THIS_MODULE);
|
|
|
|
/* Activate timer */
|
|
epx_c3_start();
|
|
epx_c3_pet();
|
|
|
|
epx_c3_alive = 1;
|
|
printk(KERN_INFO "Started watchdog timer.\n");
|
|
|
|
return nonseekable_open(inode, file);
|
|
}
|
|
|
|
static int epx_c3_release(struct inode *inode, struct file *file)
|
|
{
|
|
/* Shut off the timer.
|
|
* Lock it in if it's a module and we defined ...NOWAYOUT */
|
|
if (!nowayout)
|
|
epx_c3_stop(); /* Turn the WDT off */
|
|
|
|
epx_c3_alive = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t epx_c3_write(struct file *file, const char __user *data,
|
|
size_t len, loff_t *ppos)
|
|
{
|
|
/* Refresh the timer. */
|
|
if (len)
|
|
epx_c3_pet();
|
|
return len;
|
|
}
|
|
|
|
static long epx_c3_ioctl(struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
int options, retval = -EINVAL;
|
|
int __user *argp = (void __user *)arg;
|
|
static const struct watchdog_info ident = {
|
|
.options = WDIOF_KEEPALIVEPING,
|
|
.firmware_version = 0,
|
|
.identity = "Winsystems EPX-C3 H/W Watchdog",
|
|
};
|
|
|
|
switch (cmd) {
|
|
case WDIOC_GETSUPPORT:
|
|
if (copy_to_user(argp, &ident, sizeof(ident)))
|
|
return -EFAULT;
|
|
return 0;
|
|
case WDIOC_GETSTATUS:
|
|
case WDIOC_GETBOOTSTATUS:
|
|
return put_user(0, argp);
|
|
case WDIOC_SETOPTIONS:
|
|
if (get_user(options, argp))
|
|
return -EFAULT;
|
|
|
|
if (options & WDIOS_DISABLECARD) {
|
|
epx_c3_stop();
|
|
retval = 0;
|
|
}
|
|
|
|
if (options & WDIOS_ENABLECARD) {
|
|
epx_c3_start();
|
|
retval = 0;
|
|
}
|
|
|
|
return retval;
|
|
case WDIOC_KEEPALIVE:
|
|
epx_c3_pet();
|
|
return 0;
|
|
case WDIOC_GETTIMEOUT:
|
|
return put_user(WATCHDOG_TIMEOUT, argp);
|
|
default:
|
|
return -ENOTTY;
|
|
}
|
|
}
|
|
|
|
static int epx_c3_notify_sys(struct notifier_block *this, unsigned long code,
|
|
void *unused)
|
|
{
|
|
if (code == SYS_DOWN || code == SYS_HALT)
|
|
epx_c3_stop(); /* Turn the WDT off */
|
|
|
|
return NOTIFY_DONE;
|
|
}
|
|
|
|
static const struct file_operations epx_c3_fops = {
|
|
.owner = THIS_MODULE,
|
|
.llseek = no_llseek,
|
|
.write = epx_c3_write,
|
|
.unlocked_ioctl = epx_c3_ioctl,
|
|
.open = epx_c3_open,
|
|
.release = epx_c3_release,
|
|
};
|
|
|
|
static struct miscdevice epx_c3_miscdev = {
|
|
.minor = WATCHDOG_MINOR,
|
|
.name = "watchdog",
|
|
.fops = &epx_c3_fops,
|
|
};
|
|
|
|
static struct notifier_block epx_c3_notifier = {
|
|
.notifier_call = epx_c3_notify_sys,
|
|
};
|
|
|
|
static const char banner[] __initdata = KERN_INFO PFX
|
|
"Hardware Watchdog Timer for Winsystems EPX-C3 SBC: 0.1\n";
|
|
|
|
static int __init watchdog_init(void)
|
|
{
|
|
int ret;
|
|
|
|
if (!request_region(EPXC3_WATCHDOG_CTL_REG, 2, "epxc3_watchdog"))
|
|
return -EBUSY;
|
|
|
|
ret = register_reboot_notifier(&epx_c3_notifier);
|
|
if (ret) {
|
|
printk(KERN_ERR PFX "cannot register reboot notifier "
|
|
"(err=%d)\n", ret);
|
|
goto out;
|
|
}
|
|
|
|
ret = misc_register(&epx_c3_miscdev);
|
|
if (ret) {
|
|
printk(KERN_ERR PFX "cannot register miscdev on minor=%d "
|
|
"(err=%d)\n", WATCHDOG_MINOR, ret);
|
|
unregister_reboot_notifier(&epx_c3_notifier);
|
|
goto out;
|
|
}
|
|
|
|
printk(banner);
|
|
|
|
return 0;
|
|
|
|
out:
|
|
release_region(EPXC3_WATCHDOG_CTL_REG, 2);
|
|
return ret;
|
|
}
|
|
|
|
static void __exit watchdog_exit(void)
|
|
{
|
|
misc_deregister(&epx_c3_miscdev);
|
|
unregister_reboot_notifier(&epx_c3_notifier);
|
|
release_region(EPXC3_WATCHDOG_CTL_REG, 2);
|
|
}
|
|
|
|
module_init(watchdog_init);
|
|
module_exit(watchdog_exit);
|
|
|
|
MODULE_AUTHOR("Calin A. Culianu <calin@ajvar.org>");
|
|
MODULE_DESCRIPTION("Hardware Watchdog Device for Winsystems EPX-C3 SBC. "
|
|
"Note that there is no way to probe for this device -- "
|
|
"so only use it if you are *sure* you are runnning on this specific "
|
|
"SBC system from Winsystems! It writes to IO ports 0x1ee and 0x1ef!");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
|