286 lines
6.6 KiB
C
286 lines
6.6 KiB
C
/*
|
|
* RDC321x watchdog driver
|
|
*
|
|
* Copyright (C) 2007 Florian Fainelli <florian@openwrt.org>
|
|
*
|
|
* This driver is highly inspired from the cpu5_wdt driver
|
|
*
|
|
* 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.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/moduleparam.h>
|
|
#include <linux/types.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/miscdevice.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/init.h>
|
|
#include <linux/ioport.h>
|
|
#include <linux/timer.h>
|
|
#include <linux/completion.h>
|
|
#include <linux/jiffies.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/watchdog.h>
|
|
#include <linux/io.h>
|
|
#include <linux/uaccess.h>
|
|
|
|
#include <asm/mach-rdc321x/rdc321x_defs.h>
|
|
|
|
#define RDC_WDT_MASK 0x80000000 /* Mask */
|
|
#define RDC_WDT_EN 0x00800000 /* Enable bit */
|
|
#define RDC_WDT_WTI 0x00200000 /* Generate CPU reset/NMI/WDT on timeout */
|
|
#define RDC_WDT_RST 0x00100000 /* Reset bit */
|
|
#define RDC_WDT_WIF 0x00040000 /* WDT IRQ Flag */
|
|
#define RDC_WDT_IRT 0x00000100 /* IRQ Routing table */
|
|
#define RDC_WDT_CNT 0x00000001 /* WDT count */
|
|
|
|
#define RDC_CLS_TMR 0x80003844 /* Clear timer */
|
|
|
|
#define RDC_WDT_INTERVAL (HZ/10+1)
|
|
|
|
static int ticks = 1000;
|
|
|
|
/* some device data */
|
|
|
|
static struct {
|
|
struct completion stop;
|
|
int running;
|
|
struct timer_list timer;
|
|
int queue;
|
|
int default_ticks;
|
|
unsigned long inuse;
|
|
spinlock_t lock;
|
|
} rdc321x_wdt_device;
|
|
|
|
/* generic helper functions */
|
|
|
|
static void rdc321x_wdt_trigger(unsigned long unused)
|
|
{
|
|
unsigned long flags;
|
|
|
|
if (rdc321x_wdt_device.running)
|
|
ticks--;
|
|
|
|
/* keep watchdog alive */
|
|
spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
|
|
outl(RDC_WDT_EN | inl(RDC3210_CFGREG_DATA),
|
|
RDC3210_CFGREG_DATA);
|
|
spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
|
|
|
|
/* requeue?? */
|
|
if (rdc321x_wdt_device.queue && ticks)
|
|
mod_timer(&rdc321x_wdt_device.timer,
|
|
jiffies + RDC_WDT_INTERVAL);
|
|
else {
|
|
/* ticks doesn't matter anyway */
|
|
complete(&rdc321x_wdt_device.stop);
|
|
}
|
|
|
|
}
|
|
|
|
static void rdc321x_wdt_reset(void)
|
|
{
|
|
ticks = rdc321x_wdt_device.default_ticks;
|
|
}
|
|
|
|
static void rdc321x_wdt_start(void)
|
|
{
|
|
unsigned long flags;
|
|
|
|
if (!rdc321x_wdt_device.queue) {
|
|
rdc321x_wdt_device.queue = 1;
|
|
|
|
/* Clear the timer */
|
|
spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
|
|
outl(RDC_CLS_TMR, RDC3210_CFGREG_ADDR);
|
|
|
|
/* Enable watchdog and set the timeout to 81.92 us */
|
|
outl(RDC_WDT_EN | RDC_WDT_CNT, RDC3210_CFGREG_DATA);
|
|
spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
|
|
|
|
mod_timer(&rdc321x_wdt_device.timer,
|
|
jiffies + RDC_WDT_INTERVAL);
|
|
}
|
|
|
|
/* if process dies, counter is not decremented */
|
|
rdc321x_wdt_device.running++;
|
|
}
|
|
|
|
static int rdc321x_wdt_stop(void)
|
|
{
|
|
if (rdc321x_wdt_device.running)
|
|
rdc321x_wdt_device.running = 0;
|
|
|
|
ticks = rdc321x_wdt_device.default_ticks;
|
|
|
|
return -EIO;
|
|
}
|
|
|
|
/* filesystem operations */
|
|
static int rdc321x_wdt_open(struct inode *inode, struct file *file)
|
|
{
|
|
if (test_and_set_bit(0, &rdc321x_wdt_device.inuse))
|
|
return -EBUSY;
|
|
|
|
return nonseekable_open(inode, file);
|
|
}
|
|
|
|
static int rdc321x_wdt_release(struct inode *inode, struct file *file)
|
|
{
|
|
clear_bit(0, &rdc321x_wdt_device.inuse);
|
|
return 0;
|
|
}
|
|
|
|
static long rdc321x_wdt_ioctl(struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
void __user *argp = (void __user *)arg;
|
|
unsigned int value;
|
|
static struct watchdog_info ident = {
|
|
.options = WDIOF_CARDRESET,
|
|
.identity = "RDC321x WDT",
|
|
};
|
|
unsigned long flags;
|
|
|
|
switch (cmd) {
|
|
case WDIOC_KEEPALIVE:
|
|
rdc321x_wdt_reset();
|
|
break;
|
|
case WDIOC_GETSTATUS:
|
|
/* Read the value from the DATA register */
|
|
spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
|
|
value = inl(RDC3210_CFGREG_DATA);
|
|
spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
|
|
if (copy_to_user(argp, &value, sizeof(int)))
|
|
return -EFAULT;
|
|
break;
|
|
case WDIOC_GETSUPPORT:
|
|
if (copy_to_user(argp, &ident, sizeof(ident)))
|
|
return -EFAULT;
|
|
break;
|
|
case WDIOC_SETOPTIONS:
|
|
if (copy_from_user(&value, argp, sizeof(int)))
|
|
return -EFAULT;
|
|
switch (value) {
|
|
case WDIOS_ENABLECARD:
|
|
rdc321x_wdt_start();
|
|
break;
|
|
case WDIOS_DISABLECARD:
|
|
return rdc321x_wdt_stop();
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
break;
|
|
default:
|
|
return -ENOTTY;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t rdc321x_wdt_write(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
if (!count)
|
|
return -EIO;
|
|
|
|
rdc321x_wdt_reset();
|
|
|
|
return count;
|
|
}
|
|
|
|
static const struct file_operations rdc321x_wdt_fops = {
|
|
.owner = THIS_MODULE,
|
|
.llseek = no_llseek,
|
|
.unlocked_ioctl = rdc321x_wdt_ioctl,
|
|
.open = rdc321x_wdt_open,
|
|
.write = rdc321x_wdt_write,
|
|
.release = rdc321x_wdt_release,
|
|
};
|
|
|
|
static struct miscdevice rdc321x_wdt_misc = {
|
|
.minor = WATCHDOG_MINOR,
|
|
.name = "watchdog",
|
|
.fops = &rdc321x_wdt_fops,
|
|
};
|
|
|
|
static int __devinit rdc321x_wdt_probe(struct platform_device *pdev)
|
|
{
|
|
int err;
|
|
|
|
err = misc_register(&rdc321x_wdt_misc);
|
|
if (err < 0) {
|
|
printk(KERN_ERR PFX "watchdog misc_register failed\n");
|
|
return err;
|
|
}
|
|
|
|
spin_lock_init(&rdc321x_wdt_device.lock);
|
|
|
|
/* Reset the watchdog */
|
|
outl(RDC_WDT_RST, RDC3210_CFGREG_DATA);
|
|
|
|
init_completion(&rdc321x_wdt_device.stop);
|
|
rdc321x_wdt_device.queue = 0;
|
|
|
|
clear_bit(0, &rdc321x_wdt_device.inuse);
|
|
|
|
setup_timer(&rdc321x_wdt_device.timer, rdc321x_wdt_trigger, 0);
|
|
|
|
rdc321x_wdt_device.default_ticks = ticks;
|
|
|
|
printk(KERN_INFO PFX "watchdog init success\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int rdc321x_wdt_remove(struct platform_device *pdev)
|
|
{
|
|
if (rdc321x_wdt_device.queue) {
|
|
rdc321x_wdt_device.queue = 0;
|
|
wait_for_completion(&rdc321x_wdt_device.stop);
|
|
}
|
|
|
|
misc_deregister(&rdc321x_wdt_misc);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver rdc321x_wdt_driver = {
|
|
.probe = rdc321x_wdt_probe,
|
|
.remove = rdc321x_wdt_remove,
|
|
.driver = {
|
|
.owner = THIS_MODULE,
|
|
.name = "rdc321x-wdt",
|
|
},
|
|
};
|
|
|
|
static int __init rdc321x_wdt_init(void)
|
|
{
|
|
return platform_driver_register(&rdc321x_wdt_driver);
|
|
}
|
|
|
|
static void __exit rdc321x_wdt_exit(void)
|
|
{
|
|
platform_driver_unregister(&rdc321x_wdt_driver);
|
|
}
|
|
|
|
module_init(rdc321x_wdt_init);
|
|
module_exit(rdc321x_wdt_exit);
|
|
|
|
MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
|
|
MODULE_DESCRIPTION("RDC321x watchdog driver");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
|