dt-bindings: ata: Convert Allwinner AHCI controller to a schema

The Allwinner SoCs have a AHCI controllers that is supported in Linux, with
a matching Device Tree binding.

Now that we have the DT validation in place, let's convert the device tree
bindings for that controller over to a YAML schemas.

Signed-off-by: Maxime Ripard <[e-mail]>
[robh: 'maxItems: 1' for resets]
Signed-off-by: Rob Herring <[e-mail]>

Documentation/devicetree/bindings/ata/ahci-platform.txt

···
 
 Required properties:
 - compatible        : compatible string, one of:
-  - "allwinner,sun4i-a10-ahci"
-  - "allwinner,sun8i-r40-ahci"
   - "brcm,iproc-ahci"
   - "hisilicon,hisi-ahci"
   - "cavium,octeon-7130-ahci"
···
 - #address-cells    : number of cells to encode an address
 - #size-cells       : number of cells representing the size of an address
 
-For allwinner,sun8i-r40-ahci, the reset property must be present.
-
 Sub-nodes required properties:
 - reg		    : the port number
 And at least one of the following properties:
···
 		reg = <0xffe08000 0x1000>;
 		interrupts = <115>;
         };
-
-	ahci: sata@1c18000 {
-		compatible = "allwinner,sun4i-a10-ahci";
-		reg = <0x01c18000 0x1000>;
-		interrupts = <56>;
-		clocks = <&pll6 0>, <&ahb_gates 25>;
-		target-supply = <&reg_ahci_5v>;
-	};
 
 With sub-nodes:
 	sata@f7e90000 {

Documentation/devicetree/bindings/ata/allwinner,sun4i-a10-ahci.yaml

···
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/ata/allwinner,sun4i-a10-ahci.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Allwinner A10 AHCI SATA Controller bindings
+
+maintainers:
+  - Chen-Yu Tsai <[e-mail]>
+  - Maxime Ripard <[e-mail]>
+
+properties:
+  compatible:
+    const: allwinner,sun4i-a10-ahci
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    items:
+      - description: AHCI Bus Clock
+      - description: AHCI Module Clock
+
+  interrupts:
+    maxItems: 1
+
+  target-supply:
+    description: Regulator for SATA target power
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - interrupts
+
+additionalProperties: false
+
+examples:
+  - |
+    ahci: sata@1c18000 {
+        compatible = "allwinner,sun4i-a10-ahci";
+        reg = <0x01c18000 0x1000>;
+        interrupts = <56>;
+        clocks = <&pll6 0>, <&ahb_gates 25>;
+        target-supply = <&reg_ahci_5v>;
+    };

Documentation/devicetree/bindings/ata/allwinner,sun8i-r40-ahci.yaml

···
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/ata/allwinner,sun8i-r40-ahci.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Allwinner R40 AHCI SATA Controller bindings
+
+maintainers:
+  - Chen-Yu Tsai <[e-mail]>
+  - Maxime Ripard <[e-mail]>
+
+properties:
+  compatible:
+    const: allwinner,sun8i-r40-ahci
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    items:
+      - description: AHCI Bus Clock
+      - description: AHCI Module Clock
+
+  interrupts:
+    maxItems: 1
+
+  resets:
+    maxItems: 1
+
+  reset-names:
+    const: ahci
+
+  ahci-supply:
+    description: Regulator for the AHCI controller
+
+  phy-supply:
+    description: Regulator for the SATA PHY power
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - interrupts
+  - resets
+  - reset-names
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/clock/sun8i-r40-ccu.h>
+    #include <dt-bindings/reset/sun8i-r40-ccu.h>
+
+    ahci: sata@1c18000 {
+        compatible = "allwinner,sun8i-r40-ahci";
+        reg = <0x01c18000 0x1000>;
+        interrupts = <GIC_SPI 56 IRQ_TYPE_LEVEL_HIGH>;
+        clocks = <&ccu CLK_BUS_SATA>, <&ccu CLK_SATA>;
+        resets = <&ccu RST_BUS_SATA>;
+        reset-names = "ahci";
+        ahci-supply = <&reg_dldo4>;
+        phy-supply = <&reg_eldo3>;
+    };
+
+...