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EVT_UFX_DEVICE_USB_STATE_CHANGE callback function (ufxclient.h)

  • Article

The client driver's implementation to update the state of the USB device.

Syntax

EVT_UFX_DEVICE_USB_STATE_CHANGE EvtUfxDeviceUsbStateChange;

void EvtUfxDeviceUsbStateChange(
  [in] UFXDEVICE unnamedParam1,
  [in] USBFN_DEVICE_STATE unnamedParam2
)
{...}

Parameters

[in] unnamedParam1

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

[in] unnamedParam2

A USBFN_DEVICE_STATE-typed flag that indicates state of the USB device.

Return value

None

Remarks

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

UFX invokes this event callback to inform the client driver about the new state of the device.

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

Examples


EVT_UFX_DEVICE_USB_STATE_CHANGE UfxDevice_EvtDeviceUsbStateChange;

VOID
UfxDevice_EvtDeviceUsbStateChange (
    _In_ UFXDEVICE UfxDevice,
    _In_ USBFN_DEVICE_STATE NewState
)
/*++

Routine Description:

    EvtDeviceUsbStateChange handler for the UFXDEVICE object.

Arguments:

    UfxDevice - UFXDEVICE object representing the device.

    NewState - The new device state.

--*/
{
    NTSTATUS Status;
    PUFXDEVICE_CONTEXT Context;
    PCONTROLLER_CONTEXT ControllerContext;
    ULONG EpIndex;
    USBFN_DEVICE_STATE OldState;
 
    PAGED_CODE();

    TraceEntry();

    Context = UfxDeviceGetContext(UfxDevice);
    ControllerContext = DeviceGetControllerContext(Context->FdoWdfDevice);
    OldState = Context->UsbState;

    TraceInformation("New STATE: %d", NewState);

    Status = UfxDeviceStopOrResumeIdle(UfxDevice, NewState, Context->UsbPort);
    LOG_NT_MSG(Status, "Failed to stop or resume idle");

    WdfWaitLockAcquire(ControllerContext->InitializeDefaultEndpointLock, NULL);
    if (ControllerContext->InitializeDefaultEndpoint == TRUE) {
        //
        // Reset endpoint 0. This is the last part of soft reset, which was postponed
        // until now, since we need to make sure EP0 is created by UFX.
        //
        DeviceInitializeDefaultEndpoint(Context->FdoWdfDevice);
        ControllerContext->InitializeDefaultEndpoint = FALSE;
    }
    WdfWaitLockRelease(ControllerContext->InitializeDefaultEndpointLock);

    if (NewState == UsbfnDeviceStateConfigured && OldState != UsbfnDeviceStateSuspended) {

        for (EpIndex = 1; EpIndex < WdfCollectionGetCount(Context->Endpoints); EpIndex++) {
            UfxEndpointConfigure(WdfCollectionGetItem(Context->Endpoints, EpIndex));
        }

        // 
        // #### TODO: Insert code to allow the controller to accept U1/U2, if supported ####
        //
       
    }


    if (NewState == UsbfnDeviceStateDetached) {
        KeSetEvent(&ControllerContext->DetachEvent,
                   IO_NO_INCREMENT,
                   FALSE);
    }

    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 PASSIVE_LEVEL

See also

UfxDeviceCreate

UfxDeviceEventComplete