dt-bindings: phy: add yaml binding for rockchip-inno-csi-dphy

Some Rockchip SoCs like the rk3368, rk3326, px30 use a CSI dphy
based on an Innosilicon IP. Add a binding for them.

Signed-off-by: Heiko Stuebner <[e-mail]>
Reviewed-by: Rob Herring <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

Documentation/devicetree/bindings/phy/rockchip-inno-csi-dphy.yaml

···
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/phy/rockchip-inno-csi-dphy.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Rockchip SoC MIPI RX0 D-PHY Device Tree Bindings
+
+maintainers:
+  - Heiko Stuebner <[e-mail]>
+
+description: |
+  The Rockchip SoC has a MIPI CSI D-PHY based on an Innosilicon IP wich
+  connects to the ISP1 (Image Signal Processing unit v1.0) for CSI cameras.
+
+properties:
+  compatible:
+    enum:
+      - rockchip,px30-csi-dphy
+      - rockchip,rk1808-csi-dphy
+      - rockchip,rk3326-csi-dphy
+      - rockchip,rk3368-csi-dphy
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    const: pclk
+
+  '#phy-cells':
+    const: 0
+
+  power-domains:
+    description: Video in/out power domain.
+    maxItems: 1
+
+  resets:
+    items:
+      - description: exclusive PHY reset line
+
+  reset-names:
+    items:
+      - const: apb
+
+  rockchip,grf:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      Some additional phy settings are access through GRF regs.
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - '#phy-cells'
+  - power-domains
+  - resets
+  - reset-names
+  - rockchip,grf
+
+additionalProperties: false
+
+examples:
+  - |
+
+    csi_dphy: phy@ff2f0000 {
+        compatible = "rockchip,px30-csi-dphy";
+        reg = <0xff2f0000 0x4000>;
+        clocks = <&cru 1>;
+        clock-names = "pclk";
+        #phy-cells = <0>;
+        power-domains = <&power 1>;
+        resets = <&cru 1>;
+        reset-names = "apb";
+        rockchip,grf = <&grf>;
+    };