fix docs

fix docs

The USB variant is more common than the PCIE/M2 in the wild, but i did not want to port it without testing it on hardware.

address comments

This is probably ok. I found the original version a bit easier to read and extend, and maybe the way to handle that is to add a new helper function like so:

address comments

Sorry I'm late, thanks for your patience.

tested on my c720 logitech usb camera. it's .. upside down in vlc for some reason, works in browser. i'll test it with other cameras but i think we can / should iterate on this in head post refactor.

tested; this works but has some pixel format negotiation issues which i think we can debug in a subsequent commit.

rebase

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use proper device structure

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rebase

ok, lemme poke warner about it. That's pretty stupid behaviour, you're right :-)

@markj would you mind eyeballing the mmap / pager stuff here? seuros is looking to refactor uvideo into a generic video layer and then drivers that implement this video API. Since uvideo got a bunch of pager/mmap related changes recently I'd like to make sure this gets done too.