dt-bindings: timer: renesas,tpu: Convert to json-schema

Convert the Renesas H8/300 Timer Pulse Unit Device Tree binding
documentation to json-schema.

Correct clock-names, as "peripheral_clk" is the name of the supplier,
and all users use "fck".

Note that there are two different bindings for the TPU, both using
"renesas,tpu": this one for using the TPU as a clock source (used on
H8/300), and a second use for using the TPU as a PWM controller (used on
ARM).  To avoid conflicts, both bindings are marked with the appropriate
"select" logic, to check for the absence respectively presence of the
"#pwm-cells" property.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: https://lore.kernel.org/r/1c33e62c3a74979c3ca9580176e6cf89384caea9.1620648868.git.geert+renesas@glider.be
Signed-off-by: Rob Herring <robh@kernel.org>

1 files changed, 56 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/timer/renesas,tpu.yaml b/Documentation/devicetree/bindings/timer/renesas,tpu.yaml
new file mode 100644
index 000000000000..01554dff23d8
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/renesas,tpu.yaml
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/timer/renesas,tpu.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Renesas H8/300 Timer Pulse Unit
+
+maintainers:
+  - Yoshinori Sato <ysato@users.sourceforge.jp>
+
+description:
+  The TPU is a 16bit timer/counter with configurable clock inputs and
+  programmable compare match.
+  This implementation supports only cascade mode.
+
+select:
+  properties:
+    compatible:
+      contains:
+        const: renesas,tpu
+    '#pwm-cells': false
+  required:
+    - compatible
+
+properties:
+  compatible:
+    const: renesas,tpu
+
+  reg:
+    items:
+      - description: First channel
+      - description: Second channel
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    const: fck
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+
+additionalProperties: false
+
+examples:
+  - |
+    tpu: tpu@ffffe0 {
+            compatible = "renesas,tpu";
+            reg = <0xffffe0 16>, <0xfffff0 12>;
+            clocks = <&pclk>;
+            clock-names = "fck";
+    };