On Sat, Jul 5, 2014 at 3:42 AM, Paul Menzel paulepanter@users.sourceforge.net wrote:

Dear Linux folks,

connecting a VGA monitor to the internal graphics device of the ASRock E350M1 [1], the brightness is much too high.

    $ lspci -tvnn
    […]
    +-01.0  Advanced Micro Devices [AMD] nee ATI Wrestler [Radeon HD 6310] [1002:9802]
    +-01.1  Advanced Micro Devices [AMD] nee ATI Wrestler HDMI Audio [Radeon HD 6250/6310] [1002:1314]
    […]

Plugging in an external AMD/ATI graphics card and connecting the VGA monitor there, the brightness is normal as expected.

    $ lspci -nn
    […]
    01:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Cedar [Radeon HD 5000/6000/7350/8350 Series] [1002:68f9]
    01:00.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI] Cedar HDMI Audio [Radeon HD 5400/6300 Series] [1002:aa68]
    […]

The software stack is the same. Any idea how I can configure or debug that? This has been verified with 3.2.x to 3.14.9.

It sounds like the DAC bg/adj values are wrong on that board (they are tuned on a per board basis and stored in the bios). You might try a bios upgrade on the board if there is one available. If not, please file a bug (https://bugs.freedesktop.org) and attach a copy of your dmesg output, the vbios from the problematic board, and if possible the output of `radeonreg regs dce4`.

To get a copy of your vbios: (as root) (use lspci to get the bus id) cd /sys/bus/pci/devices/<pci bus id> echo 1 > rom cat rom > /tmp/vbios.rom echo 0 > rom

You can get radeonreg here: http://cgit.freedesktop.org/~airlied/radeontool/

Alex