dt-bindings: watchdog: Convert Allwinner watchdog to a schema

The Allwinner SoCs have a watchdog supported in Linux, with a matching
Device Tree binding.

Now that we have the DT validation in place, let's convert the device tree
bindings for that controller over to a YAML schemas.

Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20190821143835.7294-2-mripard@kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml

@@ -0,0 +1,48 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/watchdog/allwinner,sun4i-a10-wdt.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Allwinner A10 Watchdog Device Tree Bindings
+
+allOf:
+  - $ref: "watchdog.yaml#"
+
+maintainers:
+  - Chen-Yu Tsai <wens@csie.org>
+  - Maxime Ripard <maxime.ripard@bootlin.com>
+
+properties:
+  compatible:
+    oneOf:
+      - const: allwinner,sun4i-a10-wdt
+      - const: allwinner,sun6i-a31-wdt
+      - items:
+          - const: allwinner,sun50i-a64-wdt
+          - const: allwinner,sun6i-a31-wdt
+      - items:
+          - const: allwinner,sun50i-h6-wdt
+          - const: allwinner,sun6i-a31-wdt
+      - items:
+          - const: allwinner,suniv-f1c100s-wdt
+          - const: allwinner,sun4i-a10-wdt
+
+  reg:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    wdt: watchdog@1c20c90 {
+        compatible = "allwinner,sun4i-a10-wdt";
+        reg = <0x01c20c90 0x10>;
+        timeout-sec = <10>;
+    };
+
+...