spi: Convert DW SPI binding to DT schema

Modern device tree bindings are supposed to be created as YAML-files
in accordance with dt-schema. This commit replaces two DW SPI legacy
bare text bindings with YAML file. As before the bindings file states
that the corresponding dts node is supposed to be compatible either
with generic DW APB SSI controller or with Microsemi/Amazon/Renesas/Intel
vendors-specific controllers, to have registers, interrupts and clocks
properties. Though in case of Microsemi version of the controller
there must be two registers resources specified. Properties like
clock-names, reg-io-width, cs-gpio, num-cs, DMA and slave device
sub-nodes are optional.

Signed-off-by: Serge Semin <[email protected]>
Reviewed-by: Rob Herring <[email protected]>
Cc: Georgy Vlasov <[email protected]>
Cc: Ramil Zaripov <[email protected]>
Cc: Alexey Malahov <[email protected]>
Cc: Thomas Bogendoerfer <[email protected]>
Cc: Feng Tang <[email protected]>
Cc: Andy Shevchenko <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Mark Brown <[email protected]>

Author: fancer

Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.txt

@@ -0,0 +1,133 @@
+# SPDX-License-Identifier: GPL-2.0-only
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/spi/snps,dw-apb-ssi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Synopsys DesignWare AMBA 2.0 Synchronous Serial Interface
+
+maintainers:
+  - Mark Brown <[email protected]>
+
+allOf:
+  - $ref: "spi-controller.yaml#"
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - mscc,ocelot-spi
+              - mscc,jaguar2-spi
+    then:
+      properties:
+        reg:
+          minItems: 2
+
+properties:
+  compatible:
+    oneOf:
+      - description: Generic DW SPI Controller
+        enum:
+          - snps,dw-apb-ssi
+          - snps,dwc-ssi-1.01a
+      - description: Microsemi Ocelot/Jaguar2 SoC SPI Controller
+        items:
+          - enum:
+              - mscc,ocelot-spi
+              - mscc,jaguar2-spi
+          - const: snps,dw-apb-ssi
+      - description: Amazon Alpine SPI Controller
+        const: amazon,alpine-dw-apb-ssi
+      - description: Renesas RZ/N1 SPI Controller
+        items:
+          - const: renesas,rzn1-spi
+          - const: snps,dw-apb-ssi
+      - description: Intel Keem Bay SPI Controller
+        const: intel,keembay-ssi
+
+  reg:
+    minItems: 1
+    items:
+      - description: DW APB SSI controller memory mapped registers
+      - description: SPI MST region map
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    minItems: 1
+    items:
+      - description: SPI Controller reference clock source
+      - description: APB interface clock source
+
+  clock-names:
+    minItems: 1
+    items:
+      - const: ssi_clk
+      - const: pclk
+
+  resets:
+    maxItems: 1
+
+  reset-names:
+    const: spi
+
+  reg-io-width:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: I/O register width (in bytes) implemented by this device
+    default: 4
+    enum: [ 2, 4 ]
+
+  num-cs:
+    default: 4
+    minimum: 1
+    maximum: 4
+
+  dmas:
+    items:
+      - description: TX DMA Channel
+      - description: RX DMA Channel
+
+  dma-names:
+    items:
+      - const: tx
+      - const: rx
+
+patternProperties:
+  "^.*@[0-9a-f]+$":
+    type: object
+    properties:
+      reg:
+        minimum: 0
+        maximum: 3
+
+      spi-rx-bus-width:
+        const: 1
+
+      spi-tx-bus-width:
+        const: 1
+
+unevaluatedProperties: false
+
+required:
+  - compatible
+  - reg
+  - "#address-cells"
+  - "#size-cells"
+  - interrupts
+  - clocks
+
+examples:
+  - |
+    spi@fff00000 {
+      compatible = "snps,dw-apb-ssi";
+      reg = <0xfff00000 0x1000>;
+      #address-cells = <1>;
+      #size-cells = <0>;
+      interrupts = <0 154 4>;
+      clocks = <&spi_m_clk>;
+      num-cs = <2>;
+      cs-gpios = <&gpio0 13 0>,
+                 <&gpio0 14 0>;
+    };
+...