dt-bindings: input: Convert Allwinner LRADC to a schema

The Allwinner SoCs have an LRADC used to report keys and 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>
Signed-off-by: Rob Herring <robh@kernel.org>

1 files changed, 95 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/input/allwinner,sun4i-a10-lradc-keys.yaml b/Documentation/devicetree/bindings/input/allwinner,sun4i-a10-lradc-keys.yaml
new file mode 100644
index 000000000000..b3bd8ef7fbd6
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/allwinner,sun4i-a10-lradc-keys.yaml
@@ -0,0 +1,95 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/input/allwinner,sun4i-a10-lradc-keys.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Allwinner A10 LRADC Device Tree Bindings
+
+maintainers:
+  - Chen-Yu Tsai <wens@csie.org>
+  - Maxime Ripard <maxime.ripard@bootlin.com>
+
+properties:
+  compatible:
+    oneOf:
+      - const: allwinner,sun4i-a10-lradc-keys
+      - const: allwinner,sun8i-a83t-r-lradc
+      - items:
+        - const: allwinner,sun50i-a64-lradc
+        - const: allwinner,sun8i-a83t-r-lradc
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  vref-supply:
+    description:
+      Regulator for the LRADC reference voltage
+
+patternProperties:
+  "^button-[0-9]+$":
+    type: object
+    properties:
+      label:
+        $ref: /schemas/types.yaml#/definitions/string
+        description: Descriptive name of the key
+
+      linux,code:
+        $ref: /schemas/types.yaml#/definitions/uint32
+        description: Keycode to emit
+
+      channel:
+        allOf:
+          - $ref: /schemas/types.yaml#/definitions/uint32
+          - enum: [0, 1]
+        description: ADC Channel this key is attached to
+
+      voltage:
+        $ref: /schemas/types.yaml#/definitions/uint32
+        description:
+          Voltage in microvolts at LRADC input when this key is
+          pressed
+
+    required:
+      - label
+      - linux,code
+      - channel
+      - voltage
+
+    additionalProperties: false
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - vref-supply
+
+additionalProperties: false
+
+examples:
+  - |
+    lradc: lradc@1c22800 {
+        compatible = "allwinner,sun4i-a10-lradc-keys";
+        reg = <0x01c22800 0x100>;
+        interrupts = <31>;
+        vref-supply = <&reg_vcc3v0>;
+
+        button-191 {
+            label = "Volume Up";
+            linux,code = <115>;
+            channel = <0>;
+            voltage = <191274>;
+        };
+
+        button-392 {
+            label = "Volume Down";
+            linux,code = <114>;
+            channel = <0>;
+            voltage = <392644>;
+        };
+    };
+
+...