MFC枚举USB设备碰到的一个疑难，还没解决

代码如下：
打开USB Hub设备之后，返回句柄hHubDevice，然后使用EnumerateHubPorts来枚举Hub的端
口。疑问在代码的中文注释中。

bool CUsbEnumHub::EnumerateHubPorts(HANDLE hHubDevice, ULONG NumPorts, UsbItem* pRootItem)
{
    ULONG        index;
    BOOL        bSuccess;
    PUSB_NODE_CONNECTION_INFORMATION_EX    connectionInfo;
    CString strDriverKeyName;


    // Loop over all ports of the hub.
    // Port indices are 1 based, not 0 based.
    for (index=1; index <= NumPorts; index++)
    {
        ULONG nBytes;
        bAwUsb = FALSE;
        // Allocate space to hold the connection info for this port.
        // For now, allocate it big enough to hold info for 30 pipes.
        //
        // Endpoint numbers are 0-15.  Endpoint number 0 is the standard
        // control endpoint which is not explicitly listed in the Configuration
        // Descriptor.  There can be an IN endpoint and an OUT endpoint at
        // endpoint numbers 1-15 so there can be a maximum of 30 endpoints
        // per device configuration.
        // Should probably size this dynamically at some point.
        nBytes = sizeof(USB_NODE_CONNECTION_INFORMATION_EX) +
            sizeof(USB_PIPE_INFO) * 30;

        connectionInfo = (PUSB_NODE_CONNECTION_INFORMATION_EX)ALLOC(nBytes);

        if (connectionInfo == NULL)
        {
            OOPS();
            break;
        }

        //
        // Now query USBHUB for the USB_NODE_CONNECTION_INFORMATION_EX structure
        // for this port.  This will tell us if a device is attached to this
        // port, among other things.
        //
        connectionInfo->ConnectionIndex = index;

        bSuccess = DeviceIoControl(hHubDevice,
            IOCTL_USB_GET_NODE_CONNECTION_INFORMATION_EX,
            connectionInfo,
            nBytes,
            connectionInfo,
            nBytes,
            &nBytes,
            NULL);

        if (!bSuccess)
        {
            FREE(connectionInfo);
            continue;
        }
        UsbItem *pItemChild = new UsbItem;
        pItemChild->parent = pRootItem;
        pItemChild->strDisplayName.Format(_T("[Port%d]"), index);

        // Update the count of connected devices
        if (connectionInfo->ConnectionStatus == DeviceConnected)
        {
            //获取Dirver Key Name
            GetDriverKeyName(hHubDevice, index, pItemChild->strName);
            //在这里，判断到端口有设备连接，请教怎么获取该设备的路径，就是可以使用CreateFile打开的那种路径。
            //这里获取的Driver Key Name并不是路径，无法使用CreateFile来打开。
        }



        // If the device connected to the port is an external hub, get the
        // name of the external hub and recursively enumerate it.
        if (connectionInfo->DeviceIsHub)
        {
            CString strExtHubName;
            bSuccess = GetExternalHubName(hHubDevice, index, strExtHubName);
            if (bSuccess)
            {
                pItemChild->strName = strExtHubName;
                pItemChild->usbType = USB_TYPE_HUB;
                pRootItem->childArray.Add(pItemChild);
                EnumerateHub(strExtHubName, pItemChild);
                // On to the next port
                FREE(connectionInfo);
                continue;
            }
            else
            {
                delete pItemChild;
            }
        }
        else
        {            
            pItemChild->usbType = USB_TYPE_PORT;
            pRootItem->childArray.Add(pItemChild);
        }
        FREE(connectionInfo);
    }

    return bSuccess ? true : false;
}    

 

另一端代码，这段代码直接枚举USB设备，忽略USB Hub的枚举。这里的枚举可以获取到每
个连接到USB端口的设备的路径，可以使用CreateFile打开操作。
有没有办法把这里枚举到的USB设备和上面枚举到的USB设备建立联系呢？，代码如下：

void CTurboDemoDlg::OnBnClickedSusb()
{
    HANDLE                            hHCDev;
    HDEVINFO                        hDevInfo;
    SP_DEVICE_INTERFACE_DATA        hDevInfoData;
    PSP_DEVICE_INTERFACE_DETAIL_DATA    deviceDetailData;
    ULONG                            index;
    ULONG                            requiredLength;

    hDevInfo = SetupDiGetClassDevs((LPGUID)&GUID_CLASS_USB_DEVICE,
        NULL,
        NULL,
        (DIGCF_PRESENT | DIGCF_DEVICEINTERFACE));
    if (hDevInfo == INVALID_HANDLE_VALUE)
    {
        return ;
    }
    hDevInfoData.cbSize = sizeof(SP_DEVICE_INTERFACE_DATA);
    for (index=0; SetupDiEnumDeviceInterfaces(hDevInfo,
        0,
        (LPGUID)&GUID_CLASS_USB_DEVICE,
        index,
        &hDevInfoData); index++)
    {
        SetupDiGetDeviceInterfaceDetail(hDevInfo,
            &hDevInfoData,
            NULL,
            0,
            &requiredLength,
            NULL);

        deviceDetailData = (PSP_DEVICE_INTERFACE_DETAIL_DATA)GlobalAlloc(GPTR, requi
redLength);

        deviceDetailData->cbSize = sizeof(SP_DEVICE_INTERFACE_DETAIL_DATA);

        SetupDiGetDeviceInterfaceDetail(hDevInfo,
            &hDevInfoData,
            deviceDetailData,
            requiredLength,
            &requiredLength,
            NULL);

        //deviceDetailData->DevicePath就是USB设备的路径
        //但是使用该方法却又无法知道该设备在哪个Hub端口，苦恼。
        hHCDev = CreateFile(deviceDetailData->DevicePath,
            GENERIC_WRITE,
            FILE_SHARE_WRITE,
            NULL,
            OPEN_EXISTING,
            0,
            NULL);

        // If the handle is valid, then we've successfully opened a Host
        // Controller.  Display some info about the Host Controller itself,
        // then enumerate the Root Hub attached to the Host Controller.
        if (hHCDev != INVALID_HANDLE_VALUE)
        {
            CString strMsg;
            strMsg.Format(_T("Found: %s\n"), deviceDetailData->DevicePath);
            OutputDebugString(strMsg);

            CloseHandle(hHCDev);
        }

        GlobalFree(deviceDetailData);
    }

    SetupDiDestroyDeviceInfoList(hDevInfo);
}