Samsung Odyssey G5 S27DG50: Setting brightness causes monitor to crash

[espidev]

Running ddcutil --display=1 setvcp 10 50 causes the display to crash after a fresh reboot of the monitor. Interestingly enough, it prints Display not found.

It is inconsistent though in that if you change some settings in the monitor's settings (ex. setting the refresh rate) and then run the command, it doesn't crash anymore, but instead fails with: Verification failed for feature 10.

Downstream bug: https://bugs.kde.org/show_bug.cgi?id=494522

[rockowitz]

Please clarify what is meant by the display crashing and monitor reboot. What exactly is seen. Does rebooting entail turning the monitor off and back on?

As a workaround, I have added option --disable-ddc to branch 2.1.5-dev. It takes as an argument the Monitor Model Id for the monitor, e.g. SAM-U32H75x-3587, and causes DDC communication to be disabled for that monitor model. It can be specified multiple times. (For convenience, the Monitor Model Id is now reported as part of ddcutil detect --verbose*. )