dt-bindings: clock: convert rockchip,rk3228-cru.txt to YAML

Convert rockchip,rk3228-cru.txt to YAML.

Changes against original bindings:
  Add clocks and clock-names because the device has to have
  at least one input clock.

Signed-off-by: Johan Jonker <jbx6244@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220330121923.24240-1-jbx6244@gmail.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

Documentation/devicetree/bindings/clock/rockchip,rk3228-cru.txt

@@ -1,58 +0,0 @@
-* Rockchip RK3228 Clock and Reset Unit
-
-The RK3228 clock controller generates and supplies clock to various
-controllers within the SoC and also implements a reset controller for SoC
-peripherals.
-
-Required Properties:
-
-- compatible: should be "rockchip,rk3228-cru"
-- reg: physical base address of the controller and length of memory mapped
-  region.
-- #clock-cells: should be 1.
-- #reset-cells: should be 1.
-
-Optional Properties:
-
-- rockchip,grf: phandle to the syscon managing the "general register files"
-  If missing pll rates are not changeable, due to the missing pll lock status.
-
-Each clock is assigned an identifier and client nodes can use this identifier
-to specify the clock which they consume. All available clocks are defined as
-preprocessor macros in the dt-bindings/clock/rk3228-cru.h headers and can be
-used in device tree sources. Similar macros exist for the reset sources in
-these files.
-
-External clocks:
-
-There are several clocks that are generated outside the SoC. It is expected
-that they are defined using standard clock bindings with following
-clock-output-names:
- - "xin24m" - crystal input - required,
- - "ext_i2s" - external I2S clock - optional,
- - "ext_gmac" - external GMAC clock - optional
- - "ext_hsadc" - external HSADC clock - optional
- - "phy_50m_out" - output clock of the pll in the mac phy
-
-Example: Clock controller node:
-
-	cru: cru@20000000 {
-		compatible = "rockchip,rk3228-cru";
-		reg = <0x20000000 0x1000>;
-		rockchip,grf = <&grf>;
-
-		#clock-cells = <1>;
-		#reset-cells = <1>;
-	};
-
-Example: UART controller node that consumes the clock generated by the clock
-  controller:
-
-	uart0: serial@10110000 {
-		compatible = "snps,dw-apb-uart";
-		reg = <0x10110000 0x100>;
-		interrupts = <GIC_SPI 55 IRQ_TYPE_LEVEL_HIGH>;
-		reg-shift = <2>;
-		reg-io-width = <4>;
-		clocks = <&cru SCLK_UART0>;
-	};

Documentation/devicetree/bindings/clock/rockchip,rk3228-cru.yaml

@@ -0,0 +1,74 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/rockchip,rk3228-cru.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Rockchip RK3228 Clock and Reset Unit (CRU)
+
+maintainers:
+  - Elaine Zhang <zhangqing@rock-chips.com>
+  - Heiko Stuebner <heiko@sntech.de>
+
+description: |
+  The RK3228 clock controller generates and supplies clocks to various
+  controllers within the SoC and also implements a reset controller for SoC
+  peripherals.
+  Each clock is assigned an identifier and client nodes can use this identifier
+  to specify the clock which they consume. All available clocks are defined as
+  preprocessor macros in the dt-bindings/clock/rk3228-cru.h headers and can be
+  used in device tree sources. Similar macros exist for the reset sources in
+  these files.
+  There are several clocks that are generated outside the SoC. It is expected
+  that they are defined using standard clock bindings with following
+  clock-output-names:
+    - "xin24m"      - crystal input                          - required
+    - "ext_i2s"     - external I2S clock                     - optional
+    - "ext_gmac"    - external GMAC clock                    - optional
+    - "ext_hsadc"   - external HSADC clock                   - optional
+    - "phy_50m_out" - output clock of the pll in the mac phy
+
+properties:
+  compatible:
+    enum:
+      - rockchip,rk3228-cru
+
+  reg:
+    maxItems: 1
+
+  "#clock-cells":
+    const: 1
+
+  "#reset-cells":
+    const: 1
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    const: xin24m
+
+  rockchip,grf:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      Phandle to the syscon managing the "general register files" (GRF),
+      if missing pll rates are not changeable, due to the missing pll
+      lock status.
+
+required:
+  - compatible
+  - reg
+  - "#clock-cells"
+  - "#reset-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    cru: clock-controller@20000000 {
+      compatible = "rockchip,rk3228-cru";
+      reg = <0x20000000 0x1000>;
+      rockchip,grf = <&grf>;
+      #clock-cells = <1>;
+      #reset-cells = <1>;
+    };