dt-bindings: timer: arm,twd: Convert to json-schema

Convert the ARM Timer-Watchdog Device Tree binding documentation to
json-schema.  As the old binding document actually contained two
bindings, it is split in two document: one for the timer part, and one
for the watchdog part.

Document missing properties.
Update examples to match reality.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/3ccc0cf5319f56e230ee3b8a009f8d63afb114c1.1621521847.git.geert+renesas@glider.be
[robh: Fix up node names]
Signed-off-by: Rob Herring <robh@kernel.org>

1 files changed, 50 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/watchdog/arm,twd-wdt.yaml b/Documentation/devicetree/bindings/watchdog/arm,twd-wdt.yaml
new file mode 100644
index 000000000000..bb8901854222
--- /dev/null
+++ b/Documentation/devicetree/bindings/watchdog/arm,twd-wdt.yaml
@@ -0,0 +1,50 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/watchdog/arm,twd-wdt.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ARM Timer-Watchdog Watchdog
+
+maintainers:
+  - Rob Herring <robh@kernel.org>
+
+description:
+  ARM 11MP, Cortex-A5 and Cortex-A9 are often associated with a per-core
+  Timer-Watchdog (aka TWD), which provides both a per-cpu local timer
+  and watchdog.
+
+  The TWD is usually attached to a GIC to deliver its two per-processor
+  interrupts.
+
+properties:
+  compatible:
+    enum:
+      - arm,cortex-a9-twd-wdt
+      - arm,cortex-a5-twd-wdt
+      - arm,arm11mp-twd-wdt
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+
+    watchdog@2c000620 {
+            compatible = "arm,arm11mp-twd-wdt";
+            reg = <0x2c000620 0x20>;
+            interrupts = <GIC_PPI 14 0xf01>;
+    };