spi: Realtek RTL838x/RTL839x SPI controller

Signed-off-by: NBert Vermeulen <bert@biot.com>
Link: https://lore.kernel.org/r/20210120135928.246054-2-bert@biot.comSigned-off-by: NMark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/spi/realtek,rtl-spi.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/spi/realtek,rtl-spi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Realtek RTL838x/RTL839x SPI controller
+
+maintainers:
+  - Bert Vermeulen <bert@biot.com>
+  - Birger Koblitz <mail@birger-koblitz.de>
+
+allOf:
+  - $ref: "spi-controller.yaml#"
+
+properties:
+  compatible:
+    oneOf:
+      - const: realtek,rtl8380-spi
+      - const: realtek,rtl8382-spi
+      - const: realtek,rtl8391-spi
+      - const: realtek,rtl8392-spi
+      - const: realtek,rtl8393-spi
+
+  reg:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    spi: spi@1200 {
+        compatible = "realtek,rtl8382-spi";
+        reg = <0x1200 0x100>;
+        #address-cells = <1>;
+        #size-cells = <0>;
+    };