-/*
- * 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 <asm/io.h>
-#include <asm/uaccess.h>
-
-#include <asm/mach-rdc/rdc321x_defs.h>
-
-#define RDC_WDT_MASK 0x80000000 /* Mask */
-#define RDC_WDT_EN 0x00800000 /* Enable bit */
-#define RDC_WDT_WTI 0x00200000 /* Generate a CPU reset/NMI/WDT irq when WDT timeout is reached */
-#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)
-
-int nowayout = WATCHDOG_NOWAYOUT;
-module_param(nowayout, int, 0);
-MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
-
-static int ticks = 1000;
-
-/* some device data */
-
-static struct {
- struct completion stop;
- volatile int running;
- struct timer_list timer;
- volatile int queue;
- int default_ticks;
- unsigned long inuse;
-} rdc321x_wdt_device;
-
-/* generic helper functions */
-
-static void rdc321x_wdt_trigger(unsigned long unused)
-{
- if( rdc321x_wdt_device.running )
- ticks--;
-
- /* keep watchdog alive */
- outl(RDC_WDT_EN|inl(RDC3210_CFGREG_DATA), RDC3210_CFGREG_DATA);
-
- /* 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)
-{
- if (!rdc321x_wdt_device.queue) {
- rdc321x_wdt_device.queue = 1;
-
- /* Clear the timer */
- 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);
-
- 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 int rdc321x_wdt_ioctl(struct inode *inode, 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",
- };
-
- switch(cmd) {
- case WDIOC_KEEPALIVE:
- rdc321x_wdt_reset();
- break;
- case WDIOC_GETSTATUS:
- /* Read the value from the DATA register */
- value = inl(RDC3210_CFGREG_DATA);
- 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,
- .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;
-
- if ( (err = misc_register(&rdc321x_wdt_misc)) < 0 ) {
- printk(KERN_ERR PFX "misc_register failed\n");
- return err;
- }
-
- /* 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 "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);
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