DXGKARG_DPAUXIOTRANSMISSION structure (dispmprt.h)

The DXGKARG_DPAUXIOTRANSMISSION structure is a parameter for the DXGKDDI_DPAUXIOTRANSMISSION callback.

Syntax

typedef struct _DXGKARG_DPAUXIOTRANSMISSION {
  struct {
    UINT Write : 1;
    UINT CanUseCachedData : 1;
    UINT Reserved : 30;
  };
  UINT   RootPortIndex;
  UINT   DPCDAddress;
  BYTE   NumBytesRequested;
  UINT   DPNativeError;
  BYTE   NumBytesDone;
  BYTE   Data[MAX_DP_NATIVE_AUX_IO_SIZE];
} DXGKARG_DPAUXIOTRANSMISSION, *PDXGKARG_DPAUXIOTRANSMISSION;

Members

Write

Indicates whether the operation is read or write. A value of zero indicates that the DisplayPort Configuration Data (DPCD) operation is a read; a value of one indicates a write to the DPCD.

CanUseCachedData

When set, indicates that the driver can use cached data without actual AUX transaction.

Reserved

Reserved; do not use.

RootPortIndex

Index value of the DP-capable connector on which to perform the DPCD read or write operation. The driver returned the total number of DP-capable connectors on the GPU in a prior call to DXGKDDI_QUERYDPCAPS. Subsequent calls to DXGKDDI_DPAUXIOTRANSMISSION refer to the DP connectors with RootPortIndex ranging from 0 to NumRootPorts - 1.

DPCDAddress

The DPCD address for the read or write operation.

NumBytesRequested

Number of bytes to read/write starting at DPCDAddress.

DPNativeError

Field in which the driver can encode more details about the error when returning STATUS_DEVICE_PROTOCOL_ERROR from DXGKDDI_DPAUXIOTRANSMISSION.

NumBytesDone

Actual number of bytes that were read or written.

Data[MAX_DP_NATIVE_AUX_IO_SIZE]

Buffer containing the data to write for a write operation, or in which to receive the data for a read operation.

Requirements

Requirement	Value
Minimum supported client	Windows 10, version 2004
Header	dispmprt.h

See also

DXGKDDI_QUERYDPCAPS

DXGKDDI_DPAUXIOTRANSMISSION