UMDF 2 is the latest version of UMDF and supersedes UMDF 1. All new UMDF drivers should be written using UMDF 2. No new features are being added to UMDF 1 and there is limited support for UMDF 1 on newer versions of Windows 10. Universal Windows drivers must use UMDF 2.
For more info, see Getting Started with UMDF.
A UMDF driver can call WinUSB Functions directly if the driver cannot use the USB-specific UMDF interfaces to perform a specific operation. To call WinUSB Functions, the driver must first obtain a WinUSB interface handle by calling IWDFUsbTargetDevice::GetWinUsbHandle or IWDFUsbInterface::GetWinUsbHandle. A WinUSB interface handle is used to define the first interface in the selected configuration.
For more information, see How to Access a USB Device by Using WinUSB Functions.