usb驱动只能写不能读

读代码如下：
void
UC_ReadWriteEndpoints(
    IN WDFQUEUE Queue,
    IN WDFREQUEST Request,
    IN ULONG Length,
    IN WDF_REQUEST_TYPE RequestType)
{
    size_t totalLength = Length;
    size_t stageLength = 0;
    NTSTATUS status;
    PVOID virtualAddress = 0;
    PREQUEST_CONTEXT pRequestContext = NULL;
    WDFUSBPIPE pipe;
    WDFMEMORY memory;
    WDFMEMORY_OFFSET offset;
    WDF_OBJECT_ATTRIBUTES objectAttributes;
    PDEVICE_CONTEXT pDeviceContext;

    UC_DbgPrint(3, ("UC_ReadWriteEndpoints - begin, Length:%x\n", Length));

    // First validate input parameters.
    pDeviceContext = GetDeviceContext(WdfIoQueueGetDevice(Queue));

    if (totalLength > pDeviceContext->MaxTransferSize)
    {
        UC_DbgPrint(1, ("Transfer length > circular buffer\n"));
        status = STATUS_INVALID_PARAMETER;
        goto Exit;
    }

    if ((RequestType != WdfRequestTypeRead) &&
        (RequestType != WdfRequestTypeWrite))
    {
        UC_DbgPrint(1, ("RequestType has to be either read or write\n"));
        status = STATUS_INVALID_PARAMETER;
        goto Exit;
    }

    // Get the pipe associate with this request.
    pRequestContext = GetRequestContext(Request);

    if (RequestType == WdfRequestTypeRead)
    {
        status = WdfRequestRetrieveOutputBuffer(Request, Length, &virtualAddress, &totalLength);
        pipe = pDeviceContext->interruptReadPipe;
        pRequestContext->Read = TRUE;
    }
    else
    {
        status = WdfRequestRetrieveInputBuffer(Request, Length, &virtualAddress, &totalLength);
        pipe = pDeviceContext->interruptWritePipe;
        pRequestContext->Read = FALSE;
    }

    if (!NT_SUCCESS(status))
    {
        UC_DbgPrint(1, ("WdfRequestRetrieveInputBuffer failed\n"));
        goto Exit;
    }

    // If the totalLength exceeds MAX_TRANSFER_SIZE, we will break
    // that into multiple transfer of size no more than MAX_TRANSFER_SIZE
    // in each stage.
    if (totalLength > MAX_TRANSFER_SIZE)
    {
        stageLength = MAX_TRANSFER_SIZE;
    }
    else
    {
        stageLength = totalLength;
    }

    WDF_OBJECT_ATTRIBUTES_INIT(&objectAttributes);
    objectAttributes.ParentObject = Request;
    
    status = WdfMemoryCreatePreallocated(
        &objectAttributes,
        virtualAddress,
        totalLength,
        &memory);

    if (!NT_SUCCESS(status))
    {
        UC_DbgPrint(1, ("WdfMemoryCreatePreallocated failed\n"));
        goto Exit;
    }

    offset.BufferOffset = 0;
    offset.BufferLength = stageLength;

    // The framework format call validates to make sure that you are reading or
    // writing to the right pipe type, set the appropriate transfer flags, creates an
    // URB and initailzes the request.
    if (RequestType == WdfRequestTypeRead)
    {
        status = WdfUsbTargetPipeFormatRequestForRead(
            pipe,
            Request,
            memory,
            &offset);
    }
    else
    {
        status = WdfUsbTargetPipeFormatRequestForWrite(
            pipe,
            Request,
            memory,
            &offset);
    }

    if (!NT_SUCCESS(status))
    {
        UC_DbgPrint(1, ("WdfUsbTargetPipeFormatRequest failed 0x%x\n", status));
        goto Exit;
    }

    WdfRequestSetCompletionRoutine(
        Request,
        UC_ReadWriteCompletion,
        NULL);

    // Set REQUEST_CONTEXT parameters.
    pRequestContext->Length = totalLength - stageLength;
    pRequestContext->Numxfer = 0;

    // Send the request asynchronously
    if (!WdfRequestSend(Request, WdfUsbTargetPipeGetIoTarget(pipe), WDF_NO_SEND_OPTIONS))
    {
        UC_DbgPrint(1, ("WdfRequestSend failed\n"));
        status = WdfRequestGetStatus(Request);
        goto Exit;
    }

Exit:
    if (!NT_SUCCESS(status))
    {
        WdfRequestCompleteWithInformation(Request, status, 0);
    }

    UC_DbgPrint(3, ("UC_ReadWriteEndpoints - ends\n"));

    return;
}

使用usb hound read 看不到任何irp urb

    pDeviceContext->BulkReadPipe = WdfUsbInterfaceGetConfiguredPipe(
                                                  pDeviceContext->UsbInterface,
                                                  BULK_IN_ENDPOINT_INDEX,
                                                  NULL);
你还是先找一下这一句里面的BULK_IN_ENDPOINT_INDEX的定义吧

问题已解决，读buffer必须是pipe最大值得整数倍