dt-bindings: fpga: xilinx-spi: convert bindings to json-schema

Convert xilinx-spi bindings to DT schema format using json-schema.
Signed-off-by: Nava kishore Manne <nava.kishore.manne@amd.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230227110213.291225-1-nava.kishore.manne@amd.comSigned-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/fpga/xilinx-slave-serial.txt

-Xilinx Slave Serial SPI FPGA Manager
-
-Xilinx Spartan-6 and 7 Series FPGAs support a method of loading the
-bitstream over what is referred to as "slave serial" interface.
-The slave serial link is not technically SPI, and might require extra
-circuits in order to play nicely with other SPI slaves on the same bus.
-
-See:
-- https://www.xilinx.com/support/documentation/user_guides/ug380.pdf
-- https://www.xilinx.com/support/documentation/user_guides/ug470_7Series_Config.pdf
-- https://www.xilinx.com/support/documentation/application_notes/xapp583-fpga-configuration.pdf
-
-Required properties:
-- compatible: should contain "xlnx,fpga-slave-serial"
-- reg: spi chip select of the FPGA
-- prog_b-gpios: config pin (referred to as PROGRAM_B in the manual)
-- done-gpios: config status pin (referred to as DONE in the manual)
-
-Optional properties:
-- init-b-gpios: initialization status and configuration error pin
-                (referred to as INIT_B in the manual)
-
-Example for full FPGA configuration:
-
-	fpga-region0 {
-		compatible = "fpga-region";
-		fpga-mgr = <&fpga_mgr_spi>;
-		#address-cells = <0x1>;
-		#size-cells = <0x1>;
-	};
-
-	spi1: spi@10680 {
-		compatible = "marvell,armada-xp-spi", "marvell,orion-spi";
-		pinctrl-0 = <&spi0_pins>;
-		pinctrl-names = "default";
-		#address-cells = <1>;
-		#size-cells = <0>;
-		cell-index = <1>;
-		interrupts = <92>;
-		clocks = <&coreclk 0>;
-
-		fpga_mgr_spi: fpga-mgr@0 {
-			compatible = "xlnx,fpga-slave-serial";
-			spi-max-frequency = <60000000>;
-			spi-cpha;
-			reg = <0>;
-			prog_b-gpios = <&gpio0 29 GPIO_ACTIVE_LOW>;
-			init-b-gpios = <&gpio0 28 GPIO_ACTIVE_LOW>;
-			done-gpios = <&gpio0 9 GPIO_ACTIVE_HIGH>;
-		};
-	};

Documentation/devicetree/bindings/fpga/xlnx,fpga-slave-serial.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/fpga/xlnx,fpga-slave-serial.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Xilinx Slave Serial SPI FPGA
+
+maintainers:
+  - Nava kishore Manne <nava.kishore.manne@amd.com>
+
+description: |
+  Xilinx Spartan-6 and 7 Series FPGAs support a method of loading the bitstream
+  over what is referred to as slave serial interface.The slave serial link is
+  not technically SPI, and might require extra circuits in order to play nicely
+  with other SPI slaves on the same bus.
+
+  Datasheets:
+    https://www.xilinx.com/support/documentation/user_guides/ug380.pdf
+    https://www.xilinx.com/support/documentation/user_guides/ug470_7Series_Config.pdf
+    https://www.xilinx.com/support/documentation/application_notes/xapp583-fpga-configuration.pdf
+
+allOf:
+  - $ref: /schemas/spi/spi-peripheral-props.yaml#
+
+properties:
+  compatible:
+    enum:
+      - xlnx,fpga-slave-serial
+
+  spi-cpha: true
+
+  spi-max-frequency:
+    maximum: 60000000
+
+  reg:
+    maxItems: 1
+
+  prog_b-gpios:
+    description:
+      config pin (referred to as PROGRAM_B in the manual)
+    maxItems: 1
+
+  done-gpios:
+    description:
+      config status pin (referred to as DONE in the manual)
+    maxItems: 1
+
+  init-b-gpios:
+    description:
+      initialization status and configuration error pin
+      (referred to as INIT_B in the manual)
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - prog_b-gpios
+  - done-gpios
+  - init-b-gpios
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    spi {
+      #address-cells = <1>;
+      #size-cells = <0>;
+      fpga_mgr_spi: fpga-mgr@0 {
+        compatible = "xlnx,fpga-slave-serial";
+        spi-max-frequency = <60000000>;
+        spi-cpha;
+        reg = <0>;
+        prog_b-gpios = <&gpio0 29 GPIO_ACTIVE_LOW>;
+        init-b-gpios = <&gpio0 28 GPIO_ACTIVE_LOW>;
+        done-gpios = <&gpio0 9 GPIO_ACTIVE_HIGH>;
+      };
+    };
+...