Xorg framebuffer and brightness of screen

[Ken Moffat]

On Thu, Nov 11, 2021 at 10:16:18AM +0300, Riza Dindir wrote:
> Hello Ken
> 
> I am using gop, and a framebuffer. When i try to use the xrandr, it says
> "gamma is set to 0", or "failed to get size of gamma for output default".
> 
> I can set the gamma uaing xgamma and in the xorg.conf file.
> 
> Riza
> 
No idea what gop is - google suggests it's the american republican
party ;-)

Did you search for that "failed to get" message ?  Google gives me a lot of
different matches, some for failing to correctly add a new mode,
others for running with nvidia drivers or in virtualbox, or with out
of date manufacturer's video driver.
https://askubuntu.com/questions/441040/failed-to-get-size-of-gamma-for-output-default-when-trying-to-add-new-screen-res

For an ubuntu-based kernel with at-the-time recent intel graphics
hardware, adding a boot arg to enable alpha-quality intel support.
https://itectec.com/ubuntu/ubuntu-xrandr-failed-to-get-size-of-gamma-for-output-default-for-mdp-type-connection/

In short, finding the answer really does seem to depend on what
hardware and distro are in use.  I'm assuming you're using some sort
of linux.

ĸen
-- 
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