DXGKARG_DPSBMTRANSMISSION structure (dispmprt.h)

The DXGKARG_DPSBMTRANSMISSION structure is a parameter for the DXGKDDI_DPSBMTRANSMISSION callback.

Syntax

typedef struct _DXGKARG_DPSBMTRANSMISSION {
  struct {
    UINT CanUseCachedData : 1;
    UINT Reserved : 31;
  };
  UINT   RootPortIndex;
  UINT   BufferSizeSupplied;
  UINT   RequestLength;
  UINT   MaxReplyLength;
  UINT   DPNativeError;
  UINT   ActualReplyLength;
  BYTE   Data[1];
} DXGKARG_DPSBMTRANSMISSION, *PDXGKARG_DPSBMTRANSMISSION;

Members

CanUseCachedData

When set, indicates that the driver can return a cached data reply. This data must be in Sideband Message (SBM) packet format.

Reserved

Reserved; do not use.

RootPortIndex

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

BufferSizeSupplied

Size, in bytes, of the buffer provided in Data.

RequestLength

Size in bytes of Data in SBM packet size that the driver can directly write into DPCD range for DOWN_REQ.

MaxReplyLength

Maximum size, in bytes, that Data is large enough for receiving a reply. The driver needs to discard overflowing packet.

DPNativeError

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

ActualReplyLength

Length of the actual reply returned by the driver, in bytes.

Data[1]

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_DPSBMTRANSMISSION