UfxDeviceNotifyAttach 函数 (ufxclient.h)

通知 UFX 设备的 USB 电缆已连接。

语法

void UfxDeviceNotifyAttach(
  [in] UFXDEVICE UfxDevice
);

参数

[in] UfxDevice

驱动程序通过调用 UfxDeviceCreate 创建的 UFX 设备对象的句柄。

返回值

备注

当客户端驱动程序调用 UfxDeviceNotifyAttach 时,USB 函数类扩展 (UFX) 执行以下操作:

  • 将设备移动到 USB 规范中定义的供电状态。
  • 允许进行设备枚举。

客户端驱动程序通常从其EVT_WDF_INTERRUPT_DPC回调函数调用 UfxDeviceNotifyAttach,如以下示例所示。

VOID 
DeviceInterrupt_EvtInterruptDpc (
    _In_ WDFINTERRUPT Interrupt,
    _In_ WDFOBJECT AssociatedObject
    )
/*++

Routine Description:

    'EVT_WDF_INTERRUPT_DPC' handler for the device interrupt object.

Arguments:

    Interrupt - Associated interrupt object.

    AssociatedObject - FDO Object

--*/
{
    WDFDEVICE WdfDevice;
    PDEVICE_INTERRUPT_CONTEXT InterruptContext;
    PCONTROLLER_CONTEXT ControllerContext;
    BOOLEAN Attached;
    BOOLEAN GotAttachOrDetach;
    CONTROLLER_EVENT ControllerEvent;

    UNREFERENCED_PARAMETER(Interrupt);

    TraceEntry();

    WdfDevice = (WDFDEVICE) AssociatedObject;
    ControllerContext = DeviceGetControllerContext(WdfDevice);

    WdfSpinLockAcquire(ControllerContext->DpcLock);

    WdfInterruptAcquireLock(ControllerContext->DeviceInterrupt);
    Attached = ControllerContext->Attached;
    GotAttachOrDetach = ControllerContext->GotAttachOrDetach;
    ControllerContext->GotAttachOrDetach = FALSE;
    WdfInterruptReleaseLock(ControllerContext->DeviceInterrupt);

    //
    // Handle attach/detach events
    //
    if (GotAttachOrDetach) {
        if (Attached && ControllerContext->WasAttached) {
            //
            // We must have gotten at least one detach. Need to reset the state.
            //        
            ControllerContext->RemoteWakeupRequested = FALSE;
            ControllerContext->Suspended = FALSE;
            UfxDeviceNotifyDetach(ControllerContext->UfxDevice);
        }

        if (Attached) {
            ControllerContext->RemoteWakeupRequested = FALSE;
            ControllerContext->Suspended = FALSE;
            UfxDeviceNotifyAttach(ControllerContext->UfxDevice);
        }
    }

    ControllerContext->WasAttached = Attached;

    InterruptContext = DeviceInterruptGetContext(ControllerContext->DeviceInterrupt);

    //
    // #### TODO: Insert code to read and dispatch events from the controller ####
    // 

    // The sample will assume an endpoint event of EndpointEventTransferComplete
    ControllerEvent.Type = EventTypeEndpoint;
    ControllerEvent.u.EndpointEvent = EndpointEventTransferComplete;
    
    //
    // Handle events from the controller
    //
    switch (ControllerEvent.Type) {
    case EventTypeDevice:
        HandleDeviceEvent(WdfDevice, ControllerEvent.u.DeviceEvent);
        break;

    case EventTypeEndpoint:
        HandleEndpointEvent(WdfDevice, ControllerEvent.u.EndpointEvent);
        break;
    }

    WdfSpinLockRelease(ControllerContext->DpcLock);

    TraceExit();
}

要求

要求
最低受支持的客户端 Windows 10
目标平台 Windows
标头 ufxclient.h
Library ufxstub.lib
IRQL DISPATCH_LEVEL