EVT_WDF_DMA_ENABLER_ENABLE callback function (wdfdmaenabler.h)

Article
02/22/2024

[Applies to KMDF only]

A driver's EvtDmaEnablerEnable event callback function enables a device's DMA capability after the device enters its working (D0) state.

Syntax

EVT_WDF_DMA_ENABLER_ENABLE EvtWdfDmaEnablerEnable;

NTSTATUS EvtWdfDmaEnablerEnable(
  [in] WDFDMAENABLER DmaEnabler
)
{...}

Parameters

[in] DmaEnabler

A handle to a DMA enabler object.

Return value

EvtDmaEnablerEnable must return STATUS_SUCCESS or another status value for which NT_SUCCESS(status) equals TRUE, if it encounters no errors. Otherwise, this callback function must return a status value for which NT_SUCCESS(status) equals FALSE.

Remarks

To register an EvtDmaEnablerEnable callback function, a function driver for a DMA device places the callback function's address in a WDF_DMA_ENABLER_CONFIG structure before the driver calls WdfDmaEnablerCreate.

For more information about the EvtDmaEnablerEnable callback function, see Supporting Power Management for DMA Devices.

The EvtDmaEnablerEnable callback function is called at IRQL = PASSIVE_LEVEL. You should not make this callback function pageable.

Requirements

Requirement	Value
Target Platform	Universal
Minimum KMDF version	1.0
Header	wdfdmaenabler.h (include Wdf.h)
IRQL	PASSIVE_LEVEL (see Remarks section)