[kde-linux] resume from suspend still leaves video dark

[Gabriel M. Beddingfield]

Richard Pickett wrote:

> Except one small thing.  If I unplug the charging cable the video gets
> dimmer. It looks like this is an X or a KDE thing, since the backlight
> is
> still bright, just the colors get darker on the screen. I can even

It may still be a hardware issue, so don't rule that out just yet.  For
example, I don't believe I have *any* settings for configuring screen
brightness, and my hardware remembers the "plugged in" brightness and
"unplugged" brightness settings.

First, let's see if we can rule out KDE.  I presume that you know how to
control your init scripts.  The commands I'll use work on gentoo, so you
may have to modify them to match your setup.

1. If you have XDM/KDM running, log out and turn it off and get a fresh
start.  ('telinit 3' & 4, '/etc/init.d/xdm stop')

2. As root, check your logs.  '# tail -n 40 /var/log/everything/current'

3. As either root or user (on another virtual console), start a raw X
session:  '$ X 2>&1 | tee x-log.txt'

4. You should have a nice, bright screen.  Unplug power.  Observe.  Plug the
power back in.  Observe.

5. Close the X session with either <Ctrl>+<Alt>+<Backspace> or hitting
<Ctrl>+C in the terminal where you started the X session.

Conclusion:  If it 'did it', then the problem most likely has nothing to do
with KDE.  If you have a Knoppix CD or Windows, you may use one of those to
see how it behaves under the same circumstances.  Might give you a clue
where the problem is.

If it did, check the file x-log.txt and /var/log/everything/current for
clues.

If you rule out KDE, you may want to post to a Slack list.  -- more likely
to get a solution there.

My guess is that it's an ACPI issue, or a video driver/ACPI issue.

Please post your results!  (I'm curious...)

Hope this helps....

-gabriel