spi: dt-bindings: Convert spi-sifive binding to json-schema

Convert the spi-sifive binding to DT schema format.
Signed-off-by: Pragnesh Patel <pragnesh.patel@sifive.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/1568804927-13565-1-git-send-email-pragnesh.patel@sifive.comSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/spi/spi-sifive.txt

-SiFive SPI controller Device Tree Bindings
-------------------------------------------
-
-Required properties:
-- compatible		: Should be "sifive,<chip>-spi" and "sifive,spi<version>".
-			  Supported compatible strings are:
-			  "sifive,fu540-c000-spi" for the SiFive SPI v0 as integrated
-			  onto the SiFive FU540 chip, and "sifive,spi0" for the SiFive
-			  SPI v0 IP block with no chip integration tweaks.
-			  Please refer to sifive-blocks-ip-versioning.txt for details
-- reg			: Physical base address and size of SPI registers map
-			  A second (optional) range can indicate memory mapped flash
-- interrupts		: Must contain one entry
-- interrupt-parent	: Must be core interrupt controller
-- clocks		: Must reference the frequency given to the controller
-- #address-cells	: Must be '1', indicating which CS to use
-- #size-cells		: Must be '0'
-
-Optional properties:
-- sifive,fifo-depth		: Depth of hardware queues; defaults to 8
-- sifive,max-bits-per-word	: Maximum bits per word; defaults to 8
-
-SPI RTL that corresponds to the IP block version numbers can be found here:
-https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/spi
-
-Example:
-	spi: spi@10040000 {
-		compatible = "sifive,fu540-c000-spi", "sifive,spi0";
-		reg = <0x0 0x10040000 0x0 0x1000 0x0 0x20000000 0x0 0x10000000>;
-		interrupt-parent = <&plic>;
-		interrupts = <51>;
-		clocks = <&tlclk>;
-		#address-cells = <1>;
-		#size-cells = <0>;
-		sifive,fifo-depth = <8>;
-		sifive,max-bits-per-word = <8>;
-	};

Documentation/devicetree/bindings/spi/spi-sifive.yaml

+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/spi/spi-sifive.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SiFive SPI controller
+
+maintainers:
+  - Pragnesh Patel <pragnesh.patel@sifive.com>
+  - Paul Walmsley  <paul.walmsley@sifive.com>
+  - Palmer Dabbelt <palmer@sifive.com>
+
+allOf:
+  - $ref: "spi-controller.yaml#"
+
+properties:
+  compatible:
+    items:
+      - const: sifive,fu540-c000-spi
+      - const: sifive,spi0
+
+    description:
+      Should be "sifive,<chip>-spi" and "sifive,spi<version>".
+      Supported compatible strings are -
+      "sifive,fu540-c000-spi" for the SiFive SPI v0 as integrated
+      onto the SiFive FU540 chip, and "sifive,spi0" for the SiFive
+      SPI v0 IP block with no chip integration tweaks.
+      Please refer to sifive-blocks-ip-versioning.txt for details
+
+      SPI RTL that corresponds to the IP block version numbers can be found here -
+      https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/spi
+
+  reg:
+    maxItems: 1
+
+    description:
+      Physical base address and size of SPI registers map
+      A second (optional) range can indicate memory mapped flash
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+    description:
+      Must reference the frequency given to the controller
+
+  sifive,fifo-depth:
+    description:
+      Depth of hardware queues; defaults to 8
+    allOf:
+      - $ref: "/schemas/types.yaml#/definitions/uint32"
+      - enum: [ 8 ]
+      - default: 8
+
+  sifive,max-bits-per-word:
+    description:
+      Maximum bits per word; defaults to 8
+    allOf:
+      - $ref: "/schemas/types.yaml#/definitions/uint32"
+      - enum: [ 0, 1, 2, 3, 4, 5, 6, 7, 8 ]
+      - default: 8
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+
+examples:
+  - |
+    spi: spi@10040000 {
+      compatible = "sifive,fu540-c000-spi", "sifive,spi0";
+      reg = <0x0 0x10040000 0x0 0x1000 0x0 0x20000000 0x0 0x10000000>;
+      interrupt-parent = <&plic>;
+      interrupts = <51>;
+      clocks = <&tlclk>;
+      #address-cells = <1>;
+      #size-cells = <0>;
+      sifive,fifo-depth = <8>;
+      sifive,max-bits-per-word = <8>;
+    };
+
+...