Homebrew Wii U - Supersmash Gamecube Adapter

As it seems there is currently no shop which has the Gamecube Adapter for the Wii U On-Stock. I noticed there is one coming from Mayflash (http://www.mayflash.com/Products/NINTENDOWiiU/W012.html) and there has been some efforts to get it working on a 32u4 Microcontroller (http://kadevice.com/2015/01/first-ever-direct-3rd-party-usb-wii-u-input-february-kickstarter-/).

What I want is getting the Wii U Connection open sourced for working with e.g. a Teensy or a Arduino micro. To preserve this feature in SSB, even if the Adapters get rare (in a few years).

Is anyone up and want to contribute to the project?