A long time ago (2006,7,8?) before Sarah took over USB development, I tried to start getting fixes into the un-maintained USB stack. I submitted fixes for leaks, segfaults, and general cleanup and documentation. At the time, the "maintainer" was one of the most unhelpful, and ugly people I ever dealt with over e-mail. After months of writing with the person over a simple leak he'd introduced, I gave up, deciding to fix it on a branch, and publish our code rather than deal with that developer. I vowed I'd never go back -- and I still haven't.
I'm not saying all kernel developers are jerks, but I'm not interested in working with those that are. As such, I'm just not willing to spend my time trying to help. (And maybe some developers want to keep it that way. So, I guess we're both happier for it.)