This started as a fork of https://github.com/craigshelley/SiUSBXp (its documentation is at http://www.etheus.net/SiUSBXp_Linux_Driver) with the intention of supporting a particular device under Linux (10C4:EA61, but those IDs are generic).
Since I don't really need the whole SiUSBXp API, most likely I'll just gut this for what I need.