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EVT_WDF_DMA_ENABLER_SELFMANAGED_IO_START callback function (wdfdmaenabler.h)

[Applies to KMDF only]

A driver's EvtDmaEnablerSelfManagedIoStart event callback function starts a DMA device's self-managed I/O operations.

Syntax

EVT_WDF_DMA_ENABLER_SELFMANAGED_IO_START EvtWdfDmaEnablerSelfmanagedIoStart;

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

Parameters

[in] DmaEnabler

A handle to a DMA enabler object.

Return value

EvtDmaEnablerSelfManagedIoStart 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 EvtDmaEnablerSelfManagedIoStart 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 EvtDmaEnablerSelfManagedIoStart callback function, see Supporting Power Management for DMA Devices.

The EvtDmaEnablerSelfManagedIoStart 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)

See also

EvtDmaEnablerSelfManagedIoStop

WDF_DMA_ENABLER_CONFIG

WdfDmaEnablerCreate