[PATCH] watchdog nowayout for ib700wdt

Originally from Matt Domsch.
Adds a nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT
From 2.4

diff --git a/drivers/char/ib700wdt.c b/drivers/char/ib700wdt.c
index 91fb96ca5eb87275a69a9c8cffdad13457057a25..8f7c1671d4a7a0735f8bde3cd3937a106156a47f 100644 (file)
--- a/drivers/char/ib700wdt.c
+++ b/drivers/char/ib700wdt.c
@@ -25,6 +25,10 @@
  *
  *     (c) Copyright 1995    Alan Cox <alan@redhat.com>
  *
+ *      14-Dec-2001 Matt Domsch <Matt_Domsch@dell.com>
+ *           Added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT
+ *           Added timeout module option to override default
+ * 
  */
 
 #include <linux/config.h>
@@ -92,15 +96,36 @@ static spinlock_t ibwdt_lock;
 
 #define WD_TIMO 0              /* 30 seconds +/- 20%, from table */
 
+static int timeout_val = WD_TIMO;      /* value in table */
+static int timeout = 30;               /* in seconds */
+MODULE_PARM(timeout,"i");
+MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds, 0 < n < 30, must be even (default=30)");
+
+#ifdef CONFIG_WATCHDOG_NOWAYOUT
+static int nowayout = 1;
+#else
+static int nowayout = 0;
+#endif
+
+MODULE_PARM(nowayout,"i");
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
+
 /*
  *     Kernel methods.
  */
 
+static void __init
+ibwdt_validate_timeout(void)
+{
+       timeout_val = (30 - timeout) / 2;
+       if (timeout_val < 0 || timeout_val > 0xF) timeout_val = WD_TIMO;
+}
+
 static void
 ibwdt_ping(void)
 {
        /* Write a watchdog value */
-       outb_p(WD_TIMO, WDT_START);
+       outb_p(timeout_val, WDT_START);
 }
 
 static ssize_t
@@ -162,6 +187,9 @@ ibwdt_open(struct inode *inode, struct file *file)
                                spin_unlock(&ibwdt_lock);
                                return -EBUSY;
                        }
+                       if (nowayout) {
+                               MOD_INC_USE_COUNT;
+                       }
                        /*
                         *      Activate
                         */
@@ -181,9 +209,9 @@ ibwdt_close(struct inode *inode, struct file *file)
        lock_kernel();
        if (minor(inode->i_rdev) == WATCHDOG_MINOR) {
                spin_lock(&ibwdt_lock);
-#ifndef CONFIG_WATCHDOG_NOWAYOUT
-               outb_p(WD_TIMO, WDT_STOP);
-#endif
+               if (!nowayout) {
+                       outb_p(timeout_val, WDT_STOP);
+               }
                ibwdt_is_open = 0;
                spin_unlock(&ibwdt_lock);
        }
@@ -201,7 +229,7 @@ ibwdt_notify_sys(struct notifier_block *this, unsigned long code,
 {
        if (code == SYS_DOWN || code == SYS_HALT) {
                /* Turn the WDT off */
-               outb_p(WD_TIMO, WDT_STOP);
+               outb_p(timeout_val, WDT_STOP);
        }
        return NOTIFY_DONE;
 }
@@ -241,6 +269,7 @@ ibwdt_init(void)
 {
        printk("WDT driver for IB700 single board computer initialising.\n");
 
+       ibwdt_validate_timeout();
        spin_lock_init(&ibwdt_lock);
        misc_register(&ibwdt_miscdev);
 #if WDT_START != WDT_STOP