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EVT_UFX_DEVICE_HOST_DISCONNECT callback function (ufxclient.h)

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The client driver's implementation to disable the function controller's communication with the host.

Syntax

EVT_UFX_DEVICE_HOST_DISCONNECT EvtUfxDeviceHostDisconnect;

void EvtUfxDeviceHostDisconnect(
  [in] UFXDEVICE unnamedParam1
)
{...}

Parameters

[in] unnamedParam1

The handle to a USB device object that the client driver received in a previous call to the UfxDeviceCreate method.

Return value

None

Remarks

The client driver for the function host controller registers its EVT_UFX_DEVICE_HOST_DISCONNECT implementation with the USB function class extension (UFX) by calling the UfxDeviceCreate method.

UFX invokes this event callback to perform a soft-disconnect on the USB cable. After this call, the client driver must not initiate a connection with the host until UFX invokes EVT_UFX_DEVICE_HOST_CONNECT.

The client driver indicates completion of this event by calling the UfxDeviceEventComplete method.

Examples

EVT_UFX_DEVICE_HOST_DISCONNECT UfxDevice_EvtDeviceHostDisconnect;

VOID
UfxDevice_EvtDeviceHostDisconnect (
    _In_ UFXDEVICE UfxDevice
    )
/*++

Routine Description:

    EvtDeviceHostDisconnect callback handler for UFXDEVICE object.

Arguments:

    UfxDevice - UFXDEVICE object representing the device.

--*/
{
    PCONTROLLER_CONTEXT ControllerContext;
    PUFXDEVICE_CONTEXT DeviceContext;
    BOOLEAN EventComplete;

    TraceEntry();

    DeviceContext = UfxDeviceGetContext(UfxDevice);
    ControllerContext = DeviceGetControllerContext(DeviceContext->FdoWdfDevice);

    EventComplete = TRUE;

    //
    // #### TODO: Cancel all transfers. ####
    //

    WdfSpinLockAcquire(ControllerContext->DpcLock);

    //
    // #### TODO: Insert code to clear the run state on the controller ####
    //
    
    WdfSpinLockRelease(ControllerContext->DpcLock);

    if (EventComplete) {
        UfxDeviceEventComplete(UfxDevice, STATUS_SUCCESS);
    }

    TraceExit();
}

Requirements

Requirement Value
Target Platform Windows
Minimum KMDF version 1.0
Minimum UMDF version 2.0
Header ufxclient.h
IRQL <=DISPATCH_LEVEL

See also