watchdog: dw: Enable OF support for DW watchdog timer

Add device tree support to the DW watchdog timer.

Signed-off-by: Dinh Nguyen <dinguyen@altera.com>
Acked-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Pavel Machek <pavel@denx.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Cc: Viresh Kumar <viresh.linux@gmail.com>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: devicetree@vger.kernel.org
Cc: linux-watchdog@vger.kernel.org

2 files changed, 31 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/watchdog/dw_wdt.txt b/Documentation/devicetree/bindings/watchdog/dw_wdt.txt
new file mode 100644
index 000000000000..08e16f684f2d
--- /dev/null
+++ b/Documentation/devicetree/bindings/watchdog/dw_wdt.txt
@@ -0,0 +1,21 @@
+Synopsys Designware Watchdog Timer
+
+Required Properties:
+
+- compatible    : Should contain "snps,dw-wdt"
+- reg           : Base address and size of the watchdog timer registers.
+- clocks        : phandle + clock-specifier for the clock that drives the
+                watchdog timer.
+
+Optional Properties:
+
+- interrupts    : The interrupt used for the watchdog timeout warning.
+
+Example:
+
+        watchdog0: wd@ffd02000 {
+                compatible = "snps,dw-wdt";
+                reg = <0xffd02000 0x1000>;
+                interrupts = <0 171 4>;
+                clocks = <&per_base_clk>;
+        };
diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c
index 42cfd79edf2a..a46f5c7ee7ff 100644
--- a/drivers/watchdog/dw_wdt.c
+++ b/drivers/watchdog/dw_wdt.c
@@ -29,6 +29,7 @@
 #include <linux/miscdevice.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
+#include <linux/of.h>
 #include <linux/pm.h>
 #include <linux/platform_device.h>
 #include <linux/spinlock.h>
@@ -337,12 +338,21 @@ static int dw_wdt_drv_remove(struct platform_device *pdev)
         return 0;
 }
 
+#ifdef CONFIG_OF
+static const struct of_device_id dw_wdt_of_match[] = {
+        { .compatible = "snps,dw-wdt", },
+        { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, dw_wdt_of_match);
+#endif
+
 static struct platform_driver dw_wdt_driver = {
         .probe          = dw_wdt_drv_probe,
         .remove         = dw_wdt_drv_remove,
         .driver         = {
                 .name   = "dw_wdt",
                 .owner  = THIS_MODULE,
+                .of_match_table = of_match_ptr(dw_wdt_of_match),
                 .pm     = &dw_wdt_pm_ops,
         },
 };