watchdog: ath79_wdt: add device tree matching

Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: devicetree-discuss@lists.ozlabs.org
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

Documentation/devicetree/bindings/watchdog/qca-ar7130-wdt.txt

+* Qualcomm Atheros AR7130 Watchdog Timer (WDT) Controller
+
+Required properties:
+- compatible: must be "qca,ar7130-wdt"
+- reg: physical base address of the controller and length of memory mapped
+  region.
+
+Example:
+
+wdt@18060008 {
+	compatible = "qca,ar9330-wdt", "qca,ar7130-wdt";
+	reg = <0x18060008 0x8>;
+};

drivers/watchdog/ath79_wdt.c

@@ -33,6 +33,8 @@
 #include <linux/watchdog.h>
 #include <linux/clk.h>
 #include <linux/err.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
 
 #define DRIVER_NAME	"ath79-wdt"
 
@@ -308,6 +310,14 @@ static void ath97_wdt_shutdown(struct platform_device *pdev)
 	ath79_wdt_disable();
 }
 
+#ifdef CONFIG_OF
+static const struct of_device_id ath79_wdt_match[] = {
+	{ .compatible = "qca,ar7130-wdt" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, ath79_wdt_match);
+#endif
+
 static struct platform_driver ath79_wdt_driver = {
 	.probe		= ath79_wdt_probe,
 	.remove		= ath79_wdt_remove,
@@ -315,6 +325,7 @@ static struct platform_driver ath79_wdt_driver = {
 	.driver		= {
 		.name	= DRIVER_NAME,
 		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(ath79_wdt_match),
 	},
 };