client side ddc/ci

Dave Airlie airlied at
Wed Dec 2 01:07:06 PST 2009

> how would one talk with a monitor over DDC/CI on a user side, non root
> application. I would like to do monitor gamma curves I/O, EDID polling and
> other non standard communication.
> The /dev/i2c-xxx device nodes are root access only on my system. I can
> chmod them with o+rw, but thats shurely not the general solution.
> What is a good place to start with in Xorg?
> I have seen the ddc/XF64DDC.[h,c] and i2c/xf86i2c.[h,c] modules in the
> server. Is already one of those APIs exposed?
> As I understand, the root windows or xrandr output EDID atom is a one time
> thing and too static for my needs.

You'd need to add protocol for the client side apps to talk to the X server,.

you could possibly do this with xrandr properties or extending xrandr,
then drivers would have to talk to the i2c via X i2c or kernel i2c in kms case.


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