Here is a link to Part 1: http://doc-ok.org/?p=1095
Doc-Ok (and others) are getting closer to reverse engineering the Oculus DK2 so hopefully we can have an open source Linux SDK soon. Maybe even before Facebook/Oculus releases their official version!
We are looking for more help, so if you're on irc, pleaes join us in #openhmd on freenode.net