TDA4VM: Linux kernel error/warning messages during boot on SK-TDA4VM

Part Number: TDA4VM

Linux kernel will print some error/warning during boot process on SK-TDA4VM.

[    9.611664] cdns-mhdp8546 a000000.dp-bridge: error -EINVAL: invalid resource (null)

[    9.646213] cdns-mhdp8546 a000000.dp-bridge: Failed to get SAPB memory resource, HDCP not supported

But the display from HDMI works well inspite of the messages. I wonder if display from DP will do well too.

I've done some digging into this issue, it seems that the node dp-bridge@a000000 within the device tree of SK-TDA4VM lacks one register description.

properties:
  compatible:
    enum:
      - cdns,mhdp8546
      - ti,j721e-mhdp8546

  reg:
    minItems: 1
    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.
      - description:
          Register block of mhdptx sapb registers.

  reg-names:
    minItems: 1
    items:
      - const: mhdptx
      - const: j721e-intg
      - const: mhdptx-sapb

as described in https://www.kernel.org/doc/Documentation/devicetree/bindings/display/bridge/cdns%2Cmhdp8546.yaml

Regards,

Dashi Cao