dt-bindings: drm/bridge: Document Cadence MHDP8546 bridge bindings

Document the bindings used for the Cadence MHDP8546 DPI/DP bridge in
yaml format.
Signed-off-by: Yuti Amonkar <yamonkar@cadence.com>
Signed-off-by: Swapnil Jakhade <sjakhade@cadence.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml

+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/display/bridge/cdns,mhdp8546.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Cadence MHDP8546 bridge
+
+maintainers:
+  - Swapnil Jakhade <sjakhade@cadence.com>
+  - Yuti Amonkar <yamonkar@cadence.com>
+
+properties:
+  compatible:
+    enum:
+      - cdns,mhdp8546
+      - ti,j721e-mhdp8546
+
+  reg:
+    minItems: 1
+    maxItems: 2
+    items:
+      - description:
+          Register block of mhdptx apb registers up to PHY mapped area (AUX_CONFIG_P).
+          The AUX and PMA registers are not part of this range, they are instead
+          included in the associated PHY.
+      - description:
+          Register block for DSS_EDP0_INTG_CFG_VP registers in case of TI J7 SoCs.
+
+  reg-names:
+    minItems: 1
+    maxItems: 2
+    items:
+      - const: mhdptx
+      - const: j721e-intg
+
+  clocks:
+    maxItems: 1
+    description:
+      DP bridge clock, used by the IP to know how to translate a number of
+      clock cycles into a time (which is used to comply with DP standard timings
+      and delays).
+
+  phys:
+    maxItems: 1
+    description:
+      phandle to the DisplayPort PHY.
+
+  phy-names:
+    items:
+      - const: dpphy
+
+  power-domains:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  ports:
+    type: object
+    description:
+      Ports as described in Documentation/devicetree/bindings/graph.txt.
+
+    properties:
+      '#address-cells':
+        const: 1
+
+      '#size-cells':
+        const: 0
+
+      port@0:
+        type: object
+        description:
+          First input port representing the DP bridge input.
+
+      port@1:
+        type: object
+        description:
+          Second input port representing the DP bridge input.
+
+      port@2:
+        type: object
+        description:
+          Third input port representing the DP bridge input.
+
+      port@3:
+        type: object
+        description:
+          Fourth input port representing the DP bridge input.
+
+      port@4:
+        type: object
+        description:
+          Output port representing the DP bridge output.
+
+    required:
+      - port@0
+      - port@4
+      - '#address-cells'
+      - '#size-cells'
+
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: ti,j721e-mhdp8546
+    then:
+      properties:
+        reg:
+          minItems: 2
+        reg-names:
+          minItems: 2
+    else:
+      properties:
+        reg:
+          maxItems: 1
+        reg-names:
+          maxItems: 1
+
+required:
+  - compatible
+  - clocks
+  - reg
+  - reg-names
+  - phys
+  - phy-names
+  - interrupts
+  - ports
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    bus {
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        mhdp: dp-bridge@f0fb000000 {
+            compatible = "cdns,mhdp8546";
+            reg = <0xf0 0xfb000000 0x0 0x1000000>;
+            reg-names = "mhdptx";
+            clocks = <&mhdp_clock>;
+            phys = <&dp_phy>;
+            phy-names = "dpphy";
+            interrupts = <GIC_SPI 614 IRQ_TYPE_LEVEL_HIGH>;
+
+            ports {
+                #address-cells = <1>;
+                #size-cells = <0>;
+
+                port@0 {
+                    reg = <0>;
+                    dp_bridge_input: endpoint {
+                        remote-endpoint = <&xxx_dpi_output>;
+                    };
+                };
+
+                port@4 {
+                    reg = <4>;
+                    dp_bridge_output: endpoint {
+                        remote-endpoint = <&xxx_dp_connector_input>;
+                    };
+                };
+            };
+        };
+    };
+...