USB Bulk 读的问题

当读的长度小于设备发送的长度的时候就会出错，测试程序读4个字节，但是设备发送了100个字节
  URB Bulk or Interrupt Transfer issued
Device Object    USBPDO-8
Driver Object    usbhub

URB Function    URB_FUNCTION_BULK_OR_INTERRUPT_TRANSFER

Endpoint 81h    1 In, Bulk

Transfer Buffer Length    4

  URB Bulk or Interrupt Transfer failed
Device Object    USBPDO-8
Driver Object    usbhub

URB Function    URB_FUNCTION_BULK_OR_INTERRUPT_TRANSFER
URB Status    USBD_STATUS_BABBLE_DETECTED
Endpoint 81h    1 In, Bulk

Transfer Buffer Length    0


使用DS3.2产生的模板改的代码如下：

NTSTATUS V990USBDevice::Read(KIrp I)
{
    T << "Entering DRVDevice::Read, " << I << EOFL;
// TODO:    Check the incoming request.  Replace "FALSE" in the following
//            line with a check that returns TRUE if the request is not valid.

    if (FALSE)        // If (Request is invalid)
    {
        // Invalid parameter in the Read request
        I.Information() = 0;
        return I.PnpComplete(this, STATUS_INVALID_PARAMETER);
    }

    // Always ok to read 0 elements.
    if (I.ReadSize() == 0)
    {
        I.Information() = 0;
        return I.PnpComplete(this, STATUS_SUCCESS);
    }

    // Declare a memory object
    KMemory Mem(I.Mdl());

    ULONG dwTotalSize = I.ReadSize(CURRENT);
    ULONG dwMaxSize = Pipe1.MaximumTransferSize();

    // If the total requested read size is greater than the Maximum Transfer
    // Size for the Pipe, request to read only the Maximum Transfer Size since
    // the bus driver will fail an URB with a TransferBufferLength of greater
    // than the Maximum Transfer Size.
    if (dwTotalSize > dwMaxSize)
    {
        ASSERT(dwMaxSize);
        dwTotalSize = dwMaxSize;
    }

    // Allocate a new context structure for Irp completion
    USB_COMPLETION_INFO* pCompInfo = new (NonPagedPool) USB_COMPLETION_INFO;
    if (pCompInfo == NULL)
    {
        I.Information() = 0;
        return I.PnpComplete(this, STATUS_INSUFFICIENT_RESOURCES);
    }

// TODO:    Select the correct pipe to read from

    // Create an URB to do actual Bulk read from the pipe
    PURB pUrb = Pipe1.BuildBulkTransfer(
                    Mem,              // Where is data coming from?
                    dwTotalSize,      // How much data to read?
                    TRUE,             // direction (TRUE = IN)
                    NULL,            // Link to next URB
                    TRUE            // Allow a short transfer
                    );                

    if (pUrb == NULL)
    {
        delete pCompInfo;
        I.Information() = 0;
        return I.PnpComplete(this, STATUS_INSUFFICIENT_RESOURCES);
    }

    // Initialize context structure
    pCompInfo->m_pClass = this;
    pCompInfo->m_pUrb = pUrb;

    // Submit the URB to our USB device
    NTSTATUS status;
    status = Pipe1.SubmitUrb(I, pUrb, LinkTo(ReadComplete), pCompInfo, V990_DEFAULT_TIMEOUT);
    return status;
}


先谢谢了

建议搂住看下 ddk中usb里的例子代码, 里面的配置部分可是很有价值的!