dt-bindings: clk: Convert rockchip,rk3399-cru to DT schema

Convert the rockchip,rk3399-cru binding to DT schema format.
Tested with
ARCH=arm64 make dt_binding_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/clock/rockchip,rk3399-cru.yaml
ARCH=arm64 make dtbs_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/clock/rockchip,rk3399-cru.yaml

Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210610175613.167601-1-nfraprado@collabora.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

Documentation/devicetree/bindings/clock/rockchip,rk3399-cru.yaml

@@ -0,0 +1,92 @@
+# SPDX-License-Identifier: GPL-2.0-only
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/rockchip,rk3399-cru.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Rockchip RK3399 Clock and Reset Unit
+
+maintainers:
+  - Xing Zheng <zhengxing@rock-chips.com>
+  - Heiko Stuebner <heiko@sntech.de>
+
+description: |
+  The RK3399 clock controller generates and supplies clock 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/rk3399-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,
+    - "xin32k" - rtc clock - optional,
+    - "clkin_gmac" - external GMAC clock - optional,
+    - "clkin_i2s" - external I2S clock - optional,
+    - "pclkin_cif" - external ISP clock - optional,
+    - "clk_usbphy0_480m" - output clock of the pll in the usbphy0
+    - "clk_usbphy1_480m" - output clock of the pll in the usbphy1
+
+properties:
+  compatible:
+    enum:
+      - rockchip,rk3399-pmucru
+      - rockchip,rk3399-cru
+
+  reg:
+    maxItems: 1
+
+  "#clock-cells":
+    const: 1
+
+  "#reset-cells":
+    const: 1
+
+  clocks:
+    minItems: 1
+
+  assigned-clocks:
+    minItems: 1
+    maxItems: 64
+
+  assigned-clock-parents:
+    minItems: 1
+    maxItems: 64
+
+  assigned-clock-rates:
+    minItems: 1
+    maxItems: 64
+
+  rockchip,grf:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description: >
+      phandle to the syscon managing the "general register files". It is used
+      for GRF muxes, if missing any muxes present in the GRF will not be
+      available.
+
+required:
+  - compatible
+  - reg
+  - "#clock-cells"
+  - "#reset-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    pmucru: pmu-clock-controller@ff750000 {
+      compatible = "rockchip,rk3399-pmucru";
+      reg = <0xff750000 0x1000>;
+      #clock-cells = <1>;
+      #reset-cells = <1>;
+    };
+  - |
+    cru: clock-controller@ff760000 {
+      compatible = "rockchip,rk3399-cru";
+      reg = <0xff760000 0x1000>;
+      #clock-cells = <1>;
+      #reset-cells = <1>;
+    };