请教usb一个bulk类型的错误

我用的是pd12，中断类型的端点1的读和写都没有问题，可是bulk类型的端点2的读和写都是submiturb返回一个错误的值，不是成功也不是suspending，我的代码就是按照driverstudio自动生成的改的，如下：
请大虾指点哪里有问题

NTSTATUS UsbTestD12LytDevice::Write(KIrp I)
{

     int i;
t << \"Entering UsbTestD12LytDevice::Write, \" << I << EOL;
// 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)
{
// Invalid parameter in the Write request
I.Information() = 0;
return I.PnpComplete(this, STATUS_INVALID_PARAMETER);
}

// Always ok to write 0 elements.
if (I.WriteSize() == 0)
{
I.Information() = 0;
return I.PnpComplete(this, STATUS_SUCCESS);
}
ULONG dwTotalSize = I.WriteSize(CURRENT);
ULONG dwMaxSize = m_Endpoint2OUT.MaximumTransferSize();


if (dwTotalSize > dwMaxSize)
{
ASSERT(dwMaxSize);
dwTotalSize = dwMaxSize;
}

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

// 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);
}




PURB pUrb = m_Endpoint2OUT.BuildBulkTransfer(
Mem,          // Where is data coming from?
dwTotalSize,  // How much data to read?
FALSE,        // direction (FALSE = OUT)
NULL  // Link to next URB
);        

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 = m_Endpoint2OUT.SubmitUrb(I, pUrb, LinkTo(WriteComplete), pCompInfo, 0);
          
return status;  //这里status总是返回错误的值，不知为什么
}