diff options
| -rw-r--r-- | UsbDk/FilterDevice.cpp | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/UsbDk/FilterDevice.cpp b/UsbDk/FilterDevice.cpp index 01dfa82..74704c7 100644 --- a/UsbDk/FilterDevice.cpp +++ b/UsbDk/FilterDevice.cpp @@ -580,8 +580,18 @@ bool CUsbDkFilterDevice::CStrategist::SelectStrategy(PDEVICE_OBJECT DevObj) USB_DEVICE_DESCRIPTOR DevDescr; if (!m_Strategy->GetControlDevice()->GetDeviceDescriptor(ID, DevDescr)) { - TraceEvents(TRACE_LEVEL_ERROR, TRACE_FILTERDEVICE, "%!FUNC! Cannot query cached device descriptor"); - return false; + // If there is no cached device descriptor then we did not + // attach to this device stack during parent bus enumeration + // (see CUsbDkHubFilterStrategy::RegisterNewChild). + // In this case, the fact that WDF called our + // EVT_WDF_DRIVER_DEVICE_ADD callback for this device means that + // we are dealing with USB hub and WDF attached us to its stack + // automatically because UsbDk is registered in PNP manager as + // USB hubs filter + TraceEvents(TRACE_LEVEL_INFORMATION, TRACE_FILTERDEVICE, "%!FUNC! No cached device descriptor, assigning hub strategy"); + m_Strategy->Delete(); + m_Strategy = &m_HubStrategy; + return true; } // Device class is HUB -> Hub strategy |