DXGKCB_POWERRUNTIMECONTROLREQUEST callback function (d3dkmddi.h)
A kernel-mode display miniport driver calls DXGKCB_POWERRUNTIMECONTROLREQUEST to exchange information with the Power Engine Plug-in (PEP).
Syntax
DXGKCB_POWERRUNTIMECONTROLREQUEST DxgkcbPowerruntimecontrolrequest;
NTSTATUS DxgkcbPowerruntimecontrolrequest(
[in] IN_CONST_HANDLE hAdapter,
[in] IN LPCGUID PowerControlCode,
[in, optional] IN PVOID InBuffer,
[in] IN SIZE_T InBufferSize,
[in, optional] OUT PVOID OutBuffer,
[in] IN SIZE_T OutBufferSize,
[out] OUT PSIZE_T BytesReturned
)
{...}
Parameters
[in] hAdapter
A handle to the display adapter. The display miniport driver receives the handle from the DeviceHandle member of the DXGKRNL_INTERFACE structure in a call to its DxgkDdiStartDevice function.
[in] PowerControlCode
A pointer to a GUID that defines the meaning of the display miniport driver's control request. For more information, see Remarks.
[in, optional] InBuffer
An optional pointer to an input buffer.
[in] InBufferSize
The size, in bytes, of the optional buffer that InBuffer points to. Set to zero if no InBuffer is provided.
[in, optional] OutBuffer
An optional pointer to an output buffer.
[in] OutBufferSize
The size, in bytes, of the optional buffer that OutBuffer points to. Set to zero if no OutBuffer is provided.
[out] BytesReturned
The number of actual bytes returned in the buffer that OutBuffer points to. The returned value will be <= OutBufferSize.
Return value
DXGKCB_POWERRUNTIMECONTROLREQUEST returns STATUS_SUCCESS if it succeeds. Otherwise, it returns one of the error codes defined in Ntstatus.h.
Remarks
Note
To avoid a possible deadlock, do not call the DXGKCB_SETPOWERCOMPONENTACTIVE function until this function has returned.
DXGKCB_XXX functions are implemented by Dxgkrnl. To use this callback function, call DxgkCbPowerRuntimeControlRequest via the DXGKRNL_INTERFACE.
Although the driver can use any GUID in the PowerControlCode parameter, the following GUIDs that are defined in D3dkmddi.h are recommended. By using these GUIDs, the display port driver can issue Event Tracing for Windows (ETW) events, which are useful to profile driver performance issues.
| GUID | Meaning |
|---|---|
| GUID_DXGKDDI_POWER_VOLTAGE_UP | Increase the voltage. |
| GUID_DXGKDDI_POWER_VOLTAGE_DOWN | Decrease the voltage. |
| GUID_DXGKDDI_POWER_VOLTAGE | Change the voltage, but the driver doesn't know if the change is an increase or decrease. |
| GUID_DXGKDDI_POWER_CLOCK_UP | Increase the clock setting. |
| GUID_DXGKDDI_POWER_CLOCK_DOWN | Decrease the clock setting. |
| GUID_DXGKDDI_POWER_CLOCK | Change the clock setting, but the driver doesn't know if the change is an increase or decrease. |
| GUID_DXGKDDI_POWER_BANDWIDTH_UP | Increase the bandwidth. |
| GUID_DXGKDDI_POWER_BANDWIDTH_DOWN | Decrease the bandwidth. |
| GUID_DXGKDDI_POWER_BANDWIDTH | Change the bandwidth, but the driver doesn't know if the change is an increase or decrease. |
These GUIDs do not imply that there is any communication protocol between the display miniport driver and the PEP, nor do they imply that there are any restrictions on the values that can be passed between the display miniport driver and the PEP.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 8 (WDDM 1.2) |
| Minimum supported server | Windows Server 2012 |
| Target Platform | Desktop |
| Header | d3dkmddi.h (include D3dkmddi.h) |
| IRQL | <=DISPATCH_LEVEL |