dt-bindings: clock: renesas: rcar-usb2-clock-sel: Convert bindings to json-schema

Convert Renesas R-Car USB 2.0 clock selector bindings documentation
to json-schema.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/1604543524-31482-1-git-send-email-yoshihiro.shimoda.uh@renesas.comSigned-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

Documentation/devicetree/bindings/clock/renesas,rcar-usb2-clock-sel.txt

-* Renesas R-Car USB 2.0 clock selector
-
-This file provides information on what the device node for the R-Car USB 2.0
-clock selector.
-
-If you connect an external clock to the USB_EXTAL pin only, you should set
-the clock rate to "usb_extal" node only.
-If you connect an oscillator to both the USB_XTAL and USB_EXTAL, this module
-is not needed because this is default setting. (Of course, you can set the
-clock rates to both "usb_extal" and "usb_xtal" nodes.
-
-Case 1: An external clock connects to R-Car SoC
-	+----------+   +--- R-Car ---------------------+
-	|External  |---|USB_EXTAL ---> all usb channels|
-	|clock     |   |USB_XTAL                       |
-	+----------+   +-------------------------------+
-In this case, we need this driver with "usb_extal" clock.
-
-Case 2: An oscillator connects to R-Car SoC
-	+----------+   +--- R-Car ---------------------+
-	|Oscillator|---|USB_EXTAL -+-> all usb channels|
-	|          |---|USB_XTAL --+                   |
-	+----------+   +-------------------------------+
-In this case, we don't need this selector.
-
-Required properties:
-- compatible: "renesas,r8a7795-rcar-usb2-clock-sel" if the device is a part of
-	      an R8A7795 SoC.
-	      "renesas,r8a7796-rcar-usb2-clock-sel" if the device if a part of
-	      an R8A77960 SoC.
-	      "renesas,r8a77961-rcar-usb2-clock-sel" if the device if a part of
-	      an R8A77961 SoC.
-	      "renesas,rcar-gen3-usb2-clock-sel" for a generic R-Car Gen3
-	      compatible device.
-
-	      When compatible with the generic version, nodes must list the
-	      SoC-specific version corresponding to the platform first
-	      followed by the generic version.
-
-- reg: offset and length of the USB 2.0 clock selector register block.
-- clocks: A list of phandles and specifier pairs.
-- clock-names: Name of the clocks.
- - The functional clock of USB 2.0 host side must be "ehci_ohci"
- - The functional clock of HS-USB side must be "hs-usb-if"
- - The USB_EXTAL clock pin must be "usb_extal"
- - The USB_XTAL clock pin must be "usb_xtal"
-- #clock-cells: Must be 0
-- power-domains: A phandle and symbolic PM domain specifier.
-                 See power/renesas,rcar-sysc.yaml.
-- resets: A list of phandles and specifier pairs.
-- reset-names: Name of the resets.
- - The reset of USB 2.0 host side must be "ehci_ohci"
- - The reset of HS-USB side must be "hs-usb-if"
-
-Example (R-Car H3):
-
-	usb2_clksel: clock-controller@e6590630 {
-		compatible = "renesas,r8a7795-rcar-usb2-clock-sel",
-			     "renesas,rcar-gen3-usb2-clock-sel";
-		reg = <0 0xe6590630 0 0x02>;
-		clocks = <&cpg CPG_MOD 703>, <&cpg CPG_MOD 704>,
-			 <&usb_extal>, <&usb_xtal>;
-		clock-names = "ehci_ohci", "hs-usb-if", "usb_extal", "usb_xtal";
-		#clock-cells = <0>;
-		power-domains = <&sysc R8A7795_PD_ALWAYS_ON>;
-		resets = <&cpg 703>, <&cpg 704>;
-		reset-names = "ehci_ohci", "hs-usb-if";
-	};

Documentation/devicetree/bindings/clock/renesas,rcar-usb2-clock-sel.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/clock/renesas,rcar-usb2-clock-sel.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Renesas R-Car USB 2.0 clock selector
+
+maintainers:
+  - Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
+
+description: |
+  If you connect an external clock to the USB_EXTAL pin only, you should set
+  the clock rate to "usb_extal" node only.
+  If you connect an oscillator to both the USB_XTAL and USB_EXTAL, this module
+  is not needed because this is default setting. (Of course, you can set the
+  clock rates to both "usb_extal" and "usb_xtal" nodes.
+
+  Case 1: An external clock connects to R-Car SoC
+    +----------+   +--- R-Car ---------------------+
+    |External  |---|USB_EXTAL ---> all usb channels|
+    |clock     |   |USB_XTAL                       |
+    +----------+   +-------------------------------+
+
+  In this case, we need this driver with "usb_extal" clock.
+
+  Case 2: An oscillator connects to R-Car SoC
+    +----------+   +--- R-Car ---------------------+
+    |Oscillator|---|USB_EXTAL -+-> all usb channels|
+    |          |---|USB_XTAL --+                   |
+    +----------+   +-------------------------------+
+  In this case, we don't need this selector.
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - renesas,r8a7795-rcar-usb2-clock-sel  # R-Car H3
+          - renesas,r8a7796-rcar-usb2-clock-sel  # R-Car M3-W
+          - renesas,r8a77961-rcar-usb2-clock-sel # R-Car M3-W+
+      - const: renesas,rcar-gen3-usb2-clock-sel
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    minItems: 4
+    maxItems: 4
+
+  clock-names:
+    items:
+      - const: ehci_ohci
+      - const: hs-usb-if
+      - const: usb_extal
+      - const: usb_xtal
+
+  '#clock-cells':
+    const: 0
+
+  power-domains:
+    maxItems: 1
+
+  resets:
+    minItems: 2
+    maxItems: 2
+
+  reset-names:
+    items:
+      - const: ehci_ohci
+      - const: hs-usb-if
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - '#clock-cells'
+  - power-domains
+  - resets
+  - reset-names
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/r8a7795-cpg-mssr.h>
+    #include <dt-bindings/power/r8a7795-sysc.h>
+
+    usb2_clksel: clock-controller@e6590630 {
+        compatible = "renesas,r8a7795-rcar-usb2-clock-sel",
+                     "renesas,rcar-gen3-usb2-clock-sel";
+        reg = <0xe6590630 0x02>;
+        clocks = <&cpg CPG_MOD 703>, <&cpg CPG_MOD 704>,
+                 <&usb_extal>, <&usb_xtal>;
+        clock-names = "ehci_ohci", "hs-usb-if", "usb_extal", "usb_xtal";
+        #clock-cells = <0>;
+        power-domains = <&sysc R8A7795_PD_ALWAYS_ON>;
+        resets = <&cpg 703>, <&cpg 704>;
+        reset-names = "ehci_ohci", "hs-usb-if";
+    };