https://bugzilla.kernel.org/show_bug.cgi?id=199621
--- Comment #9 from Matthew Trescott (matthewtrescott@gmail.com) --- There is something else strange here. Even if I run the command I mentioned above, xrandr --verbose always says that output eDP-1 is using CRTC 0. It never changes, even though the screen turns on and off. I suppose the X server uses some magic ioctl calls or something that fixes it when it tries to switch to CRTC 1.