iio/dac: convert ltc2632.txt to lltc,ltc2632.yaml

Conversion of the ltc2632 to yaml format and name the file to
'lltc,ltc2632.yaml'.
Signed-off-by: Chris Ruehl <chris.ruehl@gtsys.com.hk>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Documentation/devicetree/bindings/iio/dac/lltc,ltc2632.yaml

+# SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/iio/dac/lltc,ltc2632.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Linear Technology LTC263x 12-/10-/8-Bit Rail-to-Rail DAC
+
+maintainers:
+  - Michael Hennerich <michael.hennerich@analog.com>
+
+description: |
+  Bindings for the Linear Technology LTC2632/2634/2636 DAC
+  Datasheet can be found here: https://www.analog.com/media/en/technical-documentation/data-sheets/LTC263[246].pdf
+
+properties:
+  compatible:
+    enum:
+      - lltc,ltc2632-l12
+      - lltc,ltc2632-l10
+      - lltc,ltc2632-l8
+      - lltc,ltc2632-h12
+      - lltc,ltc2632-h10
+      - lltc,ltc2632-h8
+      - lltc,ltc2634-l12
+      - lltc,ltc2634-l10
+      - lltc,ltc2634-l8
+      - lltc,ltc2634-h12
+      - lltc,ltc2634-h10
+      - lltc,ltc2634-h8
+      - lltc,ltc2636-l12
+      - lltc,ltc2636-l10
+      - lltc,ltc2636-l8
+      - lltc,ltc2636-h12
+      - lltc,ltc2636-h10
+      - lltc,ltc2636-h8
+
+  reg:
+    maxItems: 1
+
+  spi-max-frequency:
+    maximum: 2000000
+
+  vref-supply:
+    description:
+      Phandle to the external reference voltage supply. This should
+      only be set if there is an external reference voltage connected to the VREF
+      pin. If the property is not set the internal reference is used.
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    vref: regulator-vref {
+        compatible = "regulator-fixed";
+        regulator-name = "vref-ltc2632";
+        regulator-min-microvolt = <1250000>;
+        regulator-max-microvolt = <1250000>;
+        regulator-always-on;
+    };
+
+    spi {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      dac@0 {
+        compatible = "lltc,ltc2632";
+        reg = <0>;    /* CS0 */
+        spi-max-frequency = <1000000>;
+        vref-supply = <&vref>;
+      };
+    };
+...

Documentation/devicetree/bindings/iio/dac/ltc2632.txt

-Linear Technology LTC2632/2634/2636 DAC
-
-Required properties:
- - compatible: Has to contain one of the following:
-	lltc,ltc2632-l12
-	lltc,ltc2632-l10
-	lltc,ltc2632-l8
-	lltc,ltc2632-h12
-	lltc,ltc2632-h10
-	lltc,ltc2632-h8
-	lltc,ltc2634-l12
-	lltc,ltc2634-l10
-	lltc,ltc2634-l8
-	lltc,ltc2634-h12
-	lltc,ltc2634-h10
-	lltc,ltc2634-h8
-	lltc,ltc2636-l12
-	lltc,ltc2636-l10
-	lltc,ltc2636-l8
-	lltc,ltc2636-h12
-	lltc,ltc2636-h10
-	lltc,ltc2636-h8
-
-Property rules described in Documentation/devicetree/bindings/spi/spi-bus.txt
-apply. In particular, "reg" and "spi-max-frequency" properties must be given.
-
-Optional properties:
-	- vref-supply: Phandle to the external reference voltage supply. This should
-	  only be set if there is an external reference voltage connected to the VREF
-	  pin. If the property is not set the internal reference is used.
-
-Example:
-
-	vref: regulator-vref {
-		compatible = "regulator-fixed";
-		regulator-name = "vref-ltc2632";
-		regulator-min-microvolt = <1250000>;
-		regulator-max-microvolt = <1250000>;
-		regulator-always-on;
-	};
-
-	spi_master {
-		dac: ltc2632@0 {
-			compatible = "lltc,ltc2632-l12";
-			reg = <0>; /* CS0 */
-			spi-max-frequency = <1000000>;
-			vref-supply = <&vref>; /* optional */
-		};
-	};