[systemd-devel] systemd-backlight and backlight level 0

[Josh Triplett]

systemd-backlight saves backlight levels on shutdown, and restores them
on startup.  However, on some systems, backlight level 0 actually turns
the backlight *off*; this can potentially make the system unusable.
Complicating matters, on most systems, nothing pays attention to the
brightness adjustment keys in text mode.

I'd suggest one or both of the following two changes, to avoid a painful
failure mode:

- systemd-backlight should avoid saving/restoring a backlight level of
  0, and have a minimum backlight level.  (Possibly overridable via
  configuration, for people who *really* want to restore backlight level
  0.)

- Something ought to listen to the brightness keys (and perhaps other
  hotkeys) in pure text mode.  systemd seems like a good place for such
  a something to live.


- Josh Triplett