[PATCH v4 1/2] dt-bindings: gpio-mux-input: add documentation

[Mauri Sandberg <maukka@ext.kapsi.fi>]

Add documentation for a general GPIO multiplexer.

Signed-off-by: Mauri Sandberg <maukka@ext.kapsi.fi>
Tested-by: Drew Fustini <drew@beagleboard.org>
Reviewed-by: Drew Fustini <drew@beagleboard.org>
---
v3 -> v4:
 - Changed author email
 - Included Tested-by and Reviewed-by from Drew
v2 -> v3: added a complete example on dual 4-way multiplexer
v1 -> v2: added a little bit more text in the binding documenation
---
 .../bindings/gpio/gpio-mux-input.yaml         | 75 +++++++++++++++++++
 1 file changed, 75 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/gpio/gpio-mux-input.yaml

diff --git a/Documentation/devicetree/bindings/gpio/gpio-mux-input.yaml b/Documentation/devicetree/bindings/gpio/gpio-mux-input.yaml
new file mode 100644
index 000000000000..1ca4c3c8d64b
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio-mux-input.yaml
@@ -0,0 +1,75 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/gpio/gpio-mux-input.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Generic GPIO input multiplexer
+
+maintainers:
+  - Mauri Sandberg <maukka@ext.kapsi.fi>
+
+description: |
+  A generic GPIO based input multiplexer
+
+  This driver uses a mux-controller to drive the multiplexer and has a single
+  output pin for reading the inputs to the mux.
+
+  For GPIO consumer documentation see gpio.txt.
+
+properties:
+  compatible:
+    enum:
+      - gpio-mux-input
+
+  gpio-controller: true
+
+  '#gpio-cells':
+    const: 2
+
+  pin-gpios:
+    description: |
+      The GPIO pin used as the output from the multiplexer
+
+required:
+  - compatible
+  - gpio-controller
+  - "#gpio-cells"
+  - pin-gpios
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    mux: mux-controller {
+        compatible = "gpio-mux";
+        #mux-control-cells = <0>;
+
+        mux-gpios = <&gpio 9 GPIO_ACTIVE_HIGH>,
+                    <&gpio 11 GPIO_ACTIVE_HIGH>;
+    };
+
+    gpio2: key-mux1 {
+        compatible = "gpio-mux-input";
+        mux-controls = <&mux>;
+
+        gpio-controller;
+        #gpio-cells = <2>;
+
+        // GPIOs used by this node, mux pin
+        pin-gpios = <&gpio 12 GPIO_ACTIVE_HIGH>;
+    };
+
+    gpio3: key-mux2 {
+        compatible = "gpio-mux-input";
+        mux-controls = <&mux>;
+
+        gpio-controller;
+        #gpio-cells = <2>;
+
+        // GPIOs used by this node, mux pin
+        pin-gpios = <&gpio 14 GPIO_ACTIVE_HIGH>;
+    };
+
+...
-- 
2.25.1