Comment 168 for bug 1838373

So I tested it and the screen and backlight now works! However I still encounter some issues:
- Suspend/Resume still doesn't seem to power up the screen properly. Only the backlight turns on.
- When soft rebooting (e.g. systemctl reboot), grub and splash screen properly shows, but will always fail on initial modeset.
- There are rare cases when the screen on initial modeset fails even on normal power on (i.e. not from reboot).
- I can sometimes force screen power on to fail by repeatedly turning it off and on through xrandr.

But overall the fix makes everything so much better. I guess there's still a couple of cases we haven't checked, but I'm happy to start with this fix.