VIDEO_CHILD_ENUM_INFO structure (video.h)

Describes the child device to be enumerated by the miniport driver. All members are set by the video port driver.

Syntax

typedef struct _VIDEO_CHILD_ENUM_INFO {
  ULONG Size;
  ULONG ChildDescriptorSize;
  ULONG ChildIndex;
  ULONG ACPIHwId;
  PVOID ChildHwDeviceExtension;
} VIDEO_CHILD_ENUM_INFO, *PVIDEO_CHILD_ENUM_INFO;

Members

Size

The size in bytes of this structure.

ChildDescriptorSize

The size in bytes of the buffer to which pChildDescriptor points. The video port driver allocates this buffer to be large enough to accommodate a DDC2-compliant EDID structure.

ChildIndex

The index of the child device for which the system is requesting information. This member is used to enumerate devices that are not enumerated by ACPI or other operating system components. If ChildIndex is set to zero, the driver should use the value specified in ACPIHwId as the ID of the device being enumerated.

ACPIHwId

The identifier returned by the ACPI BIOS that represents the child device being enumerated. The miniport driver should use this member only if ChildIndex is zero.

The ACPIHwId returned by the firmware must match the value returned in UId by the miniport driver. The System BIOS manufacturer and the graphics IHV must synchronize these IDs.

ChildHwDeviceExtension

A pointer to a device extension specific to this child device. This member is valid only if the miniport driver filled the ChildHwDeviceExtensionSize member of VIDEO_HW_INITIALIZATION_DATA with a value other than zero.

Remarks

One parameter of the HwVidGetVideoChildDescriptor function is an instance of a VIDEO_CHILD_ENUM_INFO structure.

The ACPI_METHOD_DISPLAY_DOD alias, defined in Dispmprt.h, represents the method used to enumerate the devices attached to the display adapter. This method is required if the integrated device controller supports switching of output devices.

Requirements

See also

HwVidGetVideoChildDescriptor

VIDEO_HW_INITIALIZATION_DATA