spi: dt-bindings: sun6i: Allow Dual SPI and Quad SPI for newer SoCs

Support for Dual SPI and Quad SPI was added to the Linux driver in
commit 0605d9fb41 ("spi: sun6i: add quirk for dual and quad SPI modes
support") and commit 25453d797d ("spi: sun6i: add dual and quad SPI
modes support for R329/D1/R528/T113s").

However the binding was never updated to allow these modes. Allow them
by adding 2 and 4 to the allowed bus widths for the newer variants.

While at it, also add 0 to the allowed bus widths. This signals that
RX or TX is not available, i.e. the MISO or MOSI pin is disconnected.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Chen-Yu Tsai <wens@kernel.org>
Link: https://patch.msgid.link/20260302153559.3199783-2-wens@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/spi/allwinner,sun6i-a31-spi.yaml

@@ -6,9 +6,6 @@ $schema: http://devicetree.org/meta-schemas/core.yaml#
 
 title: Allwinner A31 SPI Controller
 
-allOf:
-  - $ref: spi-controller.yaml
-
 maintainers:
   - Chen-Yu Tsai <wens@csie.org>
   - Maxime Ripard <mripard@kernel.org>
@@ -82,11 +79,11 @@ patternProperties:
 
       spi-rx-bus-width:
         items:
-          - const: 1
+          enum: [0, 1, 2, 4]
 
       spi-tx-bus-width:
         items:
-          - const: 1
+          enum: [0, 1, 2, 4]
 
 required:
   - compatible
@@ -95,6 +92,28 @@ required:
   - clocks
   - clock-names
 
+allOf:
+  - $ref: spi-controller.yaml
+  - if:
+      not:
+        properties:
+          compatible:
+            contains:
+              enum:
+                - allwinner,sun50i-r329-spi
+                - allwinner,sun55i-a523-spi
+    then:
+      patternProperties:
+        "^.*@[0-9a-f]+":
+          properties:
+            spi-rx-bus-width:
+              items:
+                enum: [0, 1]
+
+            spi-tx-bus-width:
+              items:
+                enum: [0, 1]
+
 unevaluatedProperties: false
 
 examples: