I've been using some ATmega32U2s for a project I'm working on, and I was sick of running Windows just to program them using my AVRISP MKII in AVR Studio. Unfortunately, even the latest svn version of AVRDUDE doesn't yet have support for the 32U2. I put together a modified avrdude.conf
file that works for me, though. I made a few guesses on constants I couldn't find immediately from the datasheet, but the file works just fine for my AVRISP MKII.
You can download the file here
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