[WATCHDOG] i6300esb.c: Restructure initialization of the device

The i6300ESB watchdog should be stopped before userspace has access to the
watchdog. So fix this and restructure the initialization sequence into:
	* See if we have a i6300 device
	* make sure that we have valid module parameters
	* Initialize the device
	* register the /dev/watchdog device so that userspace has access
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

drivers/watchdog/i6300esb.c

@@ -123,7 +123,7 @@ static int esb_timer_start(void)
 	esb_unlock_registers();
 	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG);
 	/* Enable or Enable + Lock? */
-	val = 0x02 | (nowayout ? 0x01 : 0x00);
+	val = ESB_WDT_ENABLE | (nowayout ? ESB_WDT_LOCK : 0x00);
 	pci_write_config_byte(esb_pci, ESB_LOCK_REG, val);
 	spin_unlock(&esb_lock);
 	return 0;
@@ -143,7 +143,7 @@ static int esb_timer_stop(void)
 	spin_unlock(&esb_lock);
 
 	/* Returns 0 if the timer was disabled, non-zero otherwise */
-	return val & 0x01;
+	return val & ESB_WDT_ENABLE;
 }
 
 static void esb_timer_keepalive(void)
@@ -350,8 +350,6 @@ MODULE_DEVICE_TABLE(pci, esb_pci_tbl);
 
 static unsigned char __devinit esb_getdevice(void)
 {
-	u8 val1;
-	unsigned short val2;
 	/*
 	 *      Find the PCI device
 	 */
@@ -359,7 +357,9 @@ static unsigned char __devinit esb_getdevice(void)
 	esb_pci = pci_get_device(PCI_VENDOR_ID_INTEL,
 					PCI_DEVICE_ID_INTEL_ESB_9, NULL);
 
-	if (esb_pci) {
+	if (!esb_pci)
+		return 0;
+
 	if (pci_enable_device(esb_pci)) {
 		printk(KERN_ERR PFX "failed to enable device\n");
 		goto err_devput;
@@ -377,15 +377,34 @@ static unsigned char __devinit esb_getdevice(void)
 		goto err_release;
 	}
 
+	/* Done */
+	return 1;
+
+err_release:
+	pci_release_region(esb_pci, 0);
+err_disable:
+	pci_disable_device(esb_pci);
+err_devput:
+	pci_dev_put(esb_pci);
+	return 0;
+}
+
+static void __devinit esb_initdevice(void)
+{
+	u8 val1;
+	u16 val2;
+
 	/*
+	 * Config register:
+	 * Bit    5 : 0 = Enable WDT_OUTPUT
+	 * Bit    2 : 0 = set the timer frequency to the PCI clock
+	 * divided by 2^15 (approx 1KHz).
+	 * Bits 1:0 : 11 = WDT_INT_TYPE Disabled.
 	 * The watchdog has two timers, it can be setup so that the
 	 * expiry of timer1 results in an interrupt and the expiry of
 	 * timer2 results in a reboot. We set it to not generate
 	 * any interrupts as there is not much we can do with it
 	 * right now.
-		 *
-		 * We also enable reboots and set the timer frequency to
-		 * the PCI clock divided by 2^15 (approx 1KHz).
 	 */
 	pci_write_config_word(esb_pci, ESB_CONFIG_REG, 0x0003);
 
@@ -403,21 +422,12 @@ static unsigned char __devinit esb_getdevice(void)
 	if (val2 & ESB_WDT_TIMEOUT)
 		triggered = WDIOF_CARDRESET;
 
-		/* Reset trigger flag and timers */
+	/* Reset WDT_TIMEOUT flag and timers */
 	esb_unlock_registers();
 	writew((ESB_WDT_TIMEOUT | ESB_WDT_RELOAD), ESB_RELOAD_REG);
 
-		/* Done */
-		return 1;
-
-err_release:
-		pci_release_region(esb_pci, 0);
-err_disable:
-		pci_disable_device(esb_pci);
-err_devput:
-		pci_dev_put(esb_pci);
-	}
-	return 0;
+	/* And set the correct timeout value */
+	esb_timer_set_heartbeat(heartbeat);
 }
 
 static int __devinit esb_probe(struct platform_device *dev)
@@ -430,13 +440,17 @@ static int __devinit esb_probe(struct platform_device *dev)
 
 	/* Check that the heartbeat value is within it's range;
 	   if not reset to the default */
-	if (esb_timer_set_heartbeat(heartbeat)) {
-		esb_timer_set_heartbeat(WATCHDOG_HEARTBEAT);
+	if (heartbeat < 0x1 || heartbeat > 2 * 0x03ff) {
+		heartbeat = WATCHDOG_HEARTBEAT;
 		printk(KERN_INFO PFX
 			"heartbeat value must be 1<heartbeat<2046, using %d\n",
 								heartbeat);
 	}
 
+	/* Initialize the watchdog and make sure it does not run */
+	esb_initdevice();
+
+	/* Register the watchdog so that userspace has access to it */
 	ret = misc_register(&esb_miscdev);
 	if (ret != 0) {
 		printk(KERN_ERR PFX
@@ -444,7 +458,6 @@ static int __devinit esb_probe(struct platform_device *dev)
 							WATCHDOG_MINOR, ret);
 		goto err_unmap;
 	}
-	esb_timer_stop();
 	printk(KERN_INFO PFX
 		"initialized (0x%p). heartbeat=%d sec (nowayout=%d)\n",
 						BASEADDR, heartbeat, nowayout);
@@ -452,11 +465,8 @@ static int __devinit esb_probe(struct platform_device *dev)
 
 err_unmap:
 	iounmap(BASEADDR);
-/* err_release: */
 	pci_release_region(esb_pci, 0);
-/* err_disable: */
 	pci_disable_device(esb_pci);
-/* err_devput: */
 	pci_dev_put(esb_pci);
 	return ret;
 }