dt-bindings: iio: multiplexer: Convert io-channel-mux bindings to DT schema

Straight conversion of the txt file using the mux-consumer.yaml
binding now that is available.
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Peter Rosin <peda@axentia.se>
[robh: Drop quotes and $ref for mux-controls]
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210522112908.1611389-3-jic23@kernel.org

Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.txt

-I/O channel multiplexer bindings
-
-If a multiplexer is used to select which hardware signal is fed to
-e.g. an ADC channel, these bindings describe that situation.
-
-Required properties:
-- compatible : "io-channel-mux"
-- io-channels : Channel node of the parent channel that has multiplexed
-		input.
-- io-channel-names : Should be "parent".
-- #address-cells = <1>;
-- #size-cells = <0>;
-- mux-controls : Mux controller node to use for operating the mux
-- channels : List of strings, labeling the mux controller states.
-
-For each non-empty string in the channels property, an io-channel will
-be created. The number of this io-channel is the same as the index into
-the list of strings in the channels property, and also matches the mux
-controller state. The mux controller state is described in
-../mux/mux-controller.yaml
-
-Example:
-	mux: mux-controller {
-		compatible = "gpio-mux";
-		#mux-control-cells = <0>;
-
-		mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
-			    <&pioA 1 GPIO_ACTIVE_HIGH>;
-	};
-
-	adc-mux {
-		compatible = "io-channel-mux";
-		io-channels = <&adc 0>;
-		io-channel-names = "parent";
-
-		mux-controls = <&mux>;
-
-		channels = "sync", "in", "system-regulator";
-	};

Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.yaml

+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/multiplexer/io-channel-mux.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: I/O channel multiplexer bindings
+
+maintainers:
+  - Peter Rosin <peda@axentia.se>
+
+description: |
+  If a multiplexer is used to select which hardware signal is fed to
+  e.g. an ADC channel, these bindings describe that situation.
+
+  For each non-empty string in the channels property, an io-channel will be
+  created. The number of this io-channel is the same as the index into the list
+  of strings in the channels property, and also matches the mux controller
+  state. The mux controller state is described in
+  Documentation/devicetree/bindings/mux/mux-controller.yaml
+
+properties:
+
+  compatible:
+    const: io-channel-mux
+
+  io-channels:
+    maxItems: 1
+    description: Channel node of the parent channel that has multiplexed input.
+
+  io-channel-names:
+    const: parent
+
+  mux-controls: true
+  mux-control-names: true
+
+  channels:
+    $ref: /schemas/types.yaml#/definitions/string-array
+    description:
+      List of strings, labeling the mux controller states.
+
+required:
+  - compatible
+  - io-channels
+  - io-channel-names
+  - mux-controls
+  - channels
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    mux: mux-controller {
+      compatible = "gpio-mux";
+      #mux-control-cells = <0>;
+
+      mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+                  <&pioA 1 GPIO_ACTIVE_HIGH>;
+    };
+
+    adc-mux {
+      compatible = "io-channel-mux";
+      io-channels = <&adc 0>;
+      io-channel-names = "parent";
+
+      mux-controls = <&mux>;
+      channels = "sync", "in", "system-regulator";
+    };
+...

MAINTAINERS

@@ -8858,7 +8858,7 @@ IIO MULTIPLEXER
 M:	Peter Rosin <peda@axentia.se>
 L:	linux-iio@vger.kernel.org
 S:	Maintained
-F:	Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.txt
+F:	Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.yaml
 F:	drivers/iio/multiplexer/iio-mux.c
 
 IIO SCMI BASED DRIVER