[WATCHDOG] indydog nowayout fixes from 2.4

drivers/char/watchdog/indydog.c

@@ -26,6 +26,16 @@
 
 static unsigned long indydog_alive;
 static struct sgimc_misc_ctrl *mcmisc_regs; 
+static int expect_close = 0;
+
+#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)");
 
 static void indydog_ping()
 {
@@ -43,9 +53,10 @@ static int indydog_open(struct inode *inode, struct file *file)
 	
 	if( test_and_set_bit(0,&indydog_alive) )
 		return -EBUSY;
-#ifdef CONFIG_WATCHDOG_NOWAYOUT
-	MOD_INC_USE_COUNT;
-#endif
+
+	if (nowayout)
+		MOD_INC_USE_COUNT;
+
 	/*
 	 *	Activate timer
 	 */
@@ -63,16 +74,17 @@ static int indydog_release(struct inode *inode, struct file *file)
 {
 	/*
 	 *	Shut off the timer.
-	 * 	Lock it in if it's a module and we defined ...NOWAYOUT
+	 * 	Lock it in if it's a module and we set nowayout
 	 */
-#ifndef CONFIG_WATCHDOG_NOWAYOUT
-	{
-	u32 mc_ctrl0 = mcmisc_regs->cpuctrl0; 
-	mc_ctrl0 &= ~SGIMC_CCTRL0_WDOG;
-	mcmisc_regs->cpuctrl0 = mc_ctrl0;
-	printk("Stopped watchdog timer.\n");
+
+	if (expect_close) {
+		u32 mc_ctrl0 = mcmisc_regs->cpuctrl0; 
+		mc_ctrl0 &= ~SGIMC_CCTRL0_WDOG;
+		mcmisc_regs->cpuctrl0 = mc_ctrl0;
+		printk("Stopped watchdog timer.\n");
+	} else {
+		printk(KERN_CRIT "WDT device closed unexpectedly.  WDT will not stop!\n");
 	}
-#endif
 	clear_bit(0,&indydog_alive);
 	return 0;
 }
@@ -83,10 +95,23 @@ static ssize_t indydog_write(struct file *file, const char *data, size_t len, lo
 	if (ppos != &file->f_pos)
 		return -ESPIPE;
 
-	/*
-	 *	Refresh the timer.
-	 */
-	if(len) {
+	/* Refresh the timer. */
+	if (len) {
+		if (!nowayout) {
+			size_t i;
+
+			/* In case it was set long ago */
+			expect_close = 0;
+
+			for (i = 0; i != len; i++) {
+				char c;
+
+				if (get_user(c, data + i))
+					return -EFAULT;
+				if (c == 'V')
+					expect_close = 1;
+			}
+		}
 		indydog_ping();
 		return 1;
 	}
@@ -97,8 +122,10 @@ static int indydog_ioctl(struct inode *inode, struct file *file,
 	unsigned int cmd, unsigned long arg)
 {
 	static struct watchdog_info ident = {
-		identity: "Hardware Watchdog for SGI IP22",
+		.options = WDIOF_MAGICCLOSE,
+		.identity = "Hardware Watchdog for SGI IP22",
 	};
+
 	switch (cmd) {
 		default:
 			return -ENOIOCTLCMD;