ie6xx_wdt: store and show whether system was rebooted by watchdog.

index 8f541b9..6b7b520 100644
@@ -42,7 +42,7 @@
 #define RR0	0x0c
 #define RR1	0x0d
 #define WDT_RELOAD	0x01
-#define WDT_TOUT	0x02
+#define WDT_TIMEOUT	0x02
 
 #define WDTCR	0x10
 #define WDT_PRE_SEL	0x04

@@ -103,7 +103,7 @@ static int ie6xx_wdt_ping(struct watchdog_device *wdd)
 {
 	spin_lock(&ie6xx_wdt_data.unlock_sequence);
 	ie6xx_wdt_unlock_registers();
-	outb(WDT_RELOAD, ie6xx_wdt_data.sch_wdtba + RR1);
+	outb(WDT_RELOAD | WDT_TIMEOUT, ie6xx_wdt_data.sch_wdtba + RR1);
 	spin_unlock(&ie6xx_wdt_data.unlock_sequence);
 	return 0;
 }

@@ -137,7 +137,7 @@ static int ie6xx_wdt_set_timeout(struct watchdog_device *wdd, unsigned int t)
 	outl(preload, ie6xx_wdt_data.sch_wdtba + PV2);
 
 	ie6xx_wdt_unlock_registers();
-	outb(WDT_RELOAD | WDT_TOUT, ie6xx_wdt_data.sch_wdtba + RR1);
+	outb(WDT_RELOAD, ie6xx_wdt_data.sch_wdtba + RR1);
 
 	spin_unlock(&ie6xx_wdt_data.unlock_sequence);
 

@@ -160,7 +160,7 @@ static int ie6xx_wdt_start(struct watchdog_device *wdd)
 static int ie6xx_wdt_stop(struct watchdog_device *wdd)
 {
 	if (inb(ie6xx_wdt_data.sch_wdtba + WDTLR) & WDT_LOCK)
-		return -1;
+		return -EACCES; // close not allowed?!
 
 	/* Disable the watchdog timer */
 	spin_lock(&ie6xx_wdt_data.unlock_sequence);

@@ -208,8 +208,8 @@ static int ie6xx_wdt_dbg_show(struct seq_file *s, void *unused)
 		inl(ie6xx_wdt_data.sch_wdtba + DCR));
 	seq_printf(s, "WDTLR = 0x%08x\n",
 		inw(ie6xx_wdt_data.sch_wdtba + WDTLR));
-
-	seq_printf(s, "\n");
+	seq_printf(s, "Rebooted = %s\n",
+		ie6xx_wdt_dev.bootstatus & WDIOF_CARDRESET ? "Yes" : "No");
 	return 0;
 }
 

@@ -250,12 +250,14 @@ static void ie6xx_wdt_debugfs_exit(void)
 static int __devinit ie6xx_wdt_probe(struct platform_device *pdev)
 {
 	struct resource *res;
-	u8 wdtlr;
+	u8 wdtlr, rr1;
 	int ret;
 
 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
-	if (!res)
+	if (!res) {
+		dev_err(&pdev->dev, "failed to get resources\n");
 		return -ENODEV;
+	}
 
 	if (!request_region(res->start, resource_size(res), pdev->name)) {
 		dev_err(&pdev->dev, "Watchdog region 0x%llx already in use!\n",

@@ -266,6 +268,15 @@ static int __devinit ie6xx_wdt_probe(struct platform_device *pdev)
 	ie6xx_wdt_data.sch_wdtba = res->start;
 	dev_dbg(&pdev->dev, "WDT = 0x%X\n", ie6xx_wdt_data.sch_wdtba);
 
+	rr1 = inb(ie6xx_wdt_data.sch_wdtba + RR1);
+	if (rr1 & WDT_TIMEOUT) {
+		dev_warn(&pdev->dev, "Previous reboot was caused by the card\n");
+		ie6xx_wdt_dev.bootstatus |= WDIOF_CARDRESET;
+		// reset the flag
+		ie6xx_wdt_unlock_registers();
+		outb(WDT_TIMEOUT, ie6xx_wdt_data.sch_wdtba + RR1);
+	}
+
 	ie6xx_wdt_dev.timeout = timeout;
 	watchdog_set_nowayout(&ie6xx_wdt_dev, nowayout);
 

@@ -280,8 +291,9 @@ static int __devinit ie6xx_wdt_probe(struct platform_device *pdev)
 
 	ret = watchdog_register_device(&ie6xx_wdt_dev);
 	if (ret) {
+		printk(KERN_INFO "ie6xx_wdt_probe: can't register device\n");
 		dev_err(&pdev->dev,
-			"Watchdog timer: cannot register device (err =%d)\n",
+			"Watchdog timer: cannot register device (err=%d)\n",
 									ret);
 		goto misc_register_error;
 	}

index 6b7b520..6d95120 100644
@@ -83,6 +83,7 @@ MODULE_PARM_DESC(resetmode,
 static struct {
 	unsigned short sch_wdtba;
 	struct spinlock unlock_sequence;
+	struct platform_device *pdev;
 #ifdef CONFIG_DEBUG_FS
 	struct dentry *debugfs;
 #endif

@@ -147,6 +148,15 @@ static int ie6xx_wdt_set_timeout(struct watchdog_device *wdd, unsigned int t)
 
 static int ie6xx_wdt_start(struct watchdog_device *wdd)
 {
+	/* watchdog_dev.c has pinned this module, but nobody pinned lpc_sch.
+	If it's unloaded while the device is open, the device will be
+	unregistered, watchdog_dev will set its wdd to NULL and the next file
+	operation will panic. So we'd better pin lpc_sch, or more accurately,
+	whoever created the parent (pci_device) of the platform_device that
+	we're using, because it wasn't us! */
+	if (!try_module_get(ie6xx_wdt_data.pdev->dev.parent->driver->owner))
+		return -ESHUTDOWN; // driver is unloading
+
 	ie6xx_wdt_set_timeout(wdd, wdd->timeout);
 
 	/* Enable the watchdog timer */

@@ -167,6 +177,8 @@ static int ie6xx_wdt_stop(struct watchdog_device *wdd)
 	outb(0, ie6xx_wdt_data.sch_wdtba + WDTLR);
 	spin_unlock(&ie6xx_wdt_data.unlock_sequence);
 
+	module_put(ie6xx_wdt_data.pdev->dev.parent->driver->owner);
+
 	return 0;
 }
 

@@ -277,8 +289,15 @@ static int __devinit ie6xx_wdt_probe(struct platform_device *pdev)
 		outb(WDT_TIMEOUT, ie6xx_wdt_data.sch_wdtba + RR1);
 	}
 
+	// Need to remember our platform_device so we can pin its owner
+	// while the watchdog is open.
+	ie6xx_wdt_data.pdev = pdev;
+	dev_info(&pdev->dev, "pdev owner: %s\n", pdev->dev.driver->owner->name);
+
 	ie6xx_wdt_dev.timeout = timeout;
-	watchdog_set_nowayout(&ie6xx_wdt_dev, nowayout);
+	// watchdog_set_nowayout(&ie6xx_wdt_dev, nowayout);
+	if (nowayout)
+		set_bit(WDOG_NO_WAY_OUT, &ie6xx_wdt_dev.status);
 
 	spin_lock_init(&ie6xx_wdt_data.unlock_sequence);
 

@@ -304,6 +323,7 @@ misc_register_error:
 	ie6xx_wdt_debugfs_exit();
 	release_region(res->start, resource_size(res));
 	ie6xx_wdt_data.sch_wdtba = 0;
+	ie6xx_wdt_data.pdev = NULL;
 	return ret;
 }
 

@@ -317,6 +337,7 @@ static int __devexit ie6xx_wdt_remove(struct platform_device *pdev)
 	ie6xx_wdt_debugfs_exit();
 	release_region(res->start, resource_size(res));
 	ie6xx_wdt_data.sch_wdtba = 0;
+	ie6xx_wdt_data.pdev = NULL;
 
 	return 0;
 }