spi: Convert spi-slave-mt27xx to json-schema

Convert Mediatek ARM SOC's SPI Slave controller binding
to json-schema format.
Signed-off-by: Leilk Liu <leilk.liu@mediatek.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220125012330.13449-2-leilk.liu@mediatek.comSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/spi/mediatek,spi-slave-mt27xx.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/spi/mediatek,spi-slave-mt27xx.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SPI Slave controller for MediaTek ARM SoCs
+
+maintainers:
+  - Leilk Liu <leilk.liu@mediatek.com>
+
+allOf:
+  - $ref: "/schemas/spi/spi-controller.yaml#"
+
+properties:
+  compatible:
+    enum:
+      - mediatek,mt2712-spi-slave
+      - mediatek,mt8195-spi-slave
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    items:
+      - const: spi
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+  - clock-names
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/mt2712-clk.h>
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    spi@10013000 {
+      compatible = "mediatek,mt2712-spi-slave";
+      reg = <0x10013000 0x100>;
+      interrupts = <GIC_SPI 283 IRQ_TYPE_LEVEL_LOW>;
+      clocks = <&infracfg CLK_INFRA_AO_SPI1>;
+      clock-names = "spi";
+      assigned-clocks = <&topckgen CLK_TOP_SPISLV_SEL>;
+      assigned-clock-parents = <&topckgen CLK_TOP_UNIVPLL1_D2>;
+    };

Documentation/devicetree/bindings/spi/spi-slave-mt27xx.txt

-Binding for MTK SPI Slave controller
-
-Required properties:
-- compatible: should be one of the following.
-    - mediatek,mt2712-spi-slave: for mt2712 platforms
-    - mediatek,mt8195-spi-slave: for mt8195 platforms
-- reg: Address and length of the register set for the device.
-- interrupts: Should contain spi interrupt.
-- clocks: phandles to input clocks.
-  It's clock gate, and should be <&infracfg CLK_INFRA_AO_SPI1>.
-- clock-names: should be "spi" for the clock gate.
-
-Optional properties:
-- assigned-clocks: it's mux clock, should be <&topckgen CLK_TOP_SPISLV_SEL>.
-- assigned-clock-parents: parent of mux clock.
-  It's PLL, and should be one of the following.
-   -  <&topckgen CLK_TOP_UNIVPLL1_D2>: specify parent clock 312MHZ.
-				       It's the default one.
-   -  <&topckgen CLK_TOP_UNIVPLL1_D4>: specify parent clock 156MHZ.
-   -  <&topckgen CLK_TOP_UNIVPLL2_D4>: specify parent clock 104MHZ.
-   -  <&topckgen CLK_TOP_UNIVPLL1_D8>: specify parent clock 78MHZ.
-
-Example:
-- SoC Specific Portion:
-spis1: spi@10013000 {
-	compatible = "mediatek,mt2712-spi-slave";
-	reg = <0 0x10013000 0 0x100>;
-	interrupts = <GIC_SPI 283 IRQ_TYPE_LEVEL_LOW>;
-	clocks = <&infracfg CLK_INFRA_AO_SPI1>;
-	clock-names = "spi";
-	assigned-clocks = <&topckgen CLK_TOP_SPISLV_SEL>;
-	assigned-clock-parents = <&topckgen CLK_TOP_UNIVPLL1_D2>;
-};