ASoC: dt-bindings: cirrus,cs4271: Convert to dtschema

Convert the Cirrus Logic CS4271 audio CODEC bindings to DT schema.

Add missing spi-cpha, spi-cpol, '#sound-dai-cells' and port, as they
are already being used in the DTS and the driver for this device.

Switch to 'reset-gpios' and drop legacy 'reset-gpio' used in original
bindings.

Based on Animesh Agarwal cs42xx8 conversion patch.

Cc: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Link: https://lore.kernel.org/all/20240715-ep93xx-v11-0-4e924efda795@maquefel.me
Signed-off-by: Nikita Shubin <nikita.shubin@maquefel.me>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20240829-cs4271-yaml-v3-1-f1624cc838f6@maquefel.me
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/cirrus,cs4271.yaml

@@ -0,0 +1,101 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/sound/cirrus,cs4271.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Cirrus Logic CS4271 audio CODEC
+
+maintainers:
+  - Alexander Sverdlin <alexander.sverdlin@gmail.com>
+  - Nikita Shubin <nikita.shubin@maquefel.me>
+
+description:
+  The CS4271 is a stereo audio codec. This device supports both the I2C
+  and the SPI bus.
+
+allOf:
+  - $ref: dai-common.yaml#
+  - $ref: /schemas/spi/spi-peripheral-props.yaml#
+
+properties:
+  compatible:
+    const: cirrus,cs4271
+
+  reg:
+    maxItems: 1
+
+  spi-cpha: true
+
+  spi-cpol: true
+
+  '#sound-dai-cells':
+    const: 0
+
+  reset-gpios:
+    description:
+      This pin will be deasserted before communication to the codec starts.
+    maxItems: 1
+
+  va-supply:
+    description: Analog power supply.
+
+  vd-supply:
+    description: Digital power supply.
+
+  vl-supply:
+    description: Serial Control Port power supply.
+
+  port:
+    $ref: audio-graph-port.yaml#
+    unevaluatedProperties: false
+
+  cirrus,amuteb-eq-bmutec:
+    description:
+      When given, the Codec's AMUTEB=BMUTEC flag is enabled.
+    type: boolean
+
+  cirrus,enable-soft-reset:
+    description: |
+      The CS4271 requires its LRCLK and MCLK to be stable before its RESET
+      line is de-asserted. That also means that clocks cannot be changed
+      without putting the chip back into hardware reset, which also requires
+      a complete re-initialization of all registers.
+
+      One (undocumented) workaround is to assert and de-assert the PDN bit
+      in the MODE2 register. This workaround can be enabled with this DT
+      property.
+
+      Note that this is not needed in case the clocks are stable
+      throughout the entire runtime of the codec.
+    type: boolean
+
+required:
+  - compatible
+  - reg
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+        codec@0 {
+            compatible = "cirrus,cs4271";
+            reg = <0>;
+            #sound-dai-cells = <0>;
+            spi-max-frequency = <6000000>;
+            spi-cpol;
+            spi-cpha;
+            reset-gpios = <&gpio0 1 GPIO_ACTIVE_LOW>;
+            port {
+                endpoint {
+                    remote-endpoint = <&i2s_ep>;
+                };
+            };
+        };
+    };
+
+...