Dimmed brightness due to backlight restore Upstart job

[Cameron Norman]

On some systems, people are experiencing dimmed brightness settings due to the backlight restore Upstart job.

If you are experiencing this, please post the output of:

    cat /var/log/upstart/brightness-*.log

    ls -1 /sys/class/backlight

    cat /sys/class/backlight/*/brightness

    cat /sys/class/backlight/*/max_brightness

    ls -1 /var/lib/backlight

    cat /var/lib/backlight/*/brightness

Also please detail what video card you have and whether you are using non free or free drivers (if you are able to).

Thank you.

[Santiago (santileortiz)]

This affects me, I was able to turn it back at 100% by lowering the brightness bar on the power plug and then taking it to 100% again (when I boot, it's at 100% even though my screen is dim). My graphics card is a "Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller". I am attaching the output to the commands you need.

[Filipe Serras (filipeserras)]

As Cameron Norman requested, I'm posting here my system output:

filipeserras@X53S:~$ sudo cat /var/log/upstart/brightness-*.log
Using fallback value: 7
Using saved value: 15
Using saved value: 15
Using saved value: 15
Using saved value: 15
Using saved value: 15
Using fallback value: 127
Using saved value: 127
Using saved value: 127
Using saved value: 127
Using saved value: 127
Using saved value: 127

filipeserras@X53S:~$ ls -1 /sys/class/backlight
acpi_video0
radeon_bl0

filipeserras@X53S:~$ cat /sys/class/backlight/*/brightness
15
0

filipeserras@X53S:~$ cat /sys/class/backlight/*/max_brightness
15
255

ls -1 /var/lib/backlight
acpi_video0
radeon_bl0

filipeserras@X53S:~$ cat /var/lib/backlight/*/brightness
15
127

Kernel 3.13.0-32 - ATI Radeon Mobility HD 2400 using Open-Source Drivers.

On Kernel 3.13.0-46 only one output differs:

filipeserras@X53S:~$ cat /sys/class/backlight/*/brightness
15
255

I still haven't got the time to test the ISO's with Kernel 3.16 as Cody mentioned. If I get to test it I'll post the outputs here.

[Cameron Norman (cameronnemo)]

Thank you very much Filipe! Tell me, which kernel versions are you experiencing issues with? Is there any difference between the two kernels?

[Cameron Norman (cameronnemo)]

Also Filipe, if you could give this new brightness.conf a shot (replace /etc/init/brightness.conf with it), that would be great: https://github.com/CameronNemo/upstart-jobs/blob/master/brightness.conf

After replacing the file, you should remove the directory /var/lib/backlight and reboot TWICE. Then report back. Obrigado!

[codebreaker (jagadeeshwaran-k)]

Mine is always at 100% brightness.

[Filipe Serras (filipeserras)]

Hi Cameron,

I'm sorry for carrying bad news but after adding the new brightness.conf, removing the backlight directory and rebooting twice I was left with no display (completely black screen). After the first reboot I still had it, but after the second reboot it was completely gone.

So after this I decided to take a shot at the "Beta 3" ISO's with the 3.16 kernel. Unfortunately it didn't boot. Got the following errors:

[2.652959] radeon 0000:01:00.0: Fatal error during GPU init
[2.654011] [TTM] Trying to take down uninitialized memory manager type 1.

As far as issues with kernel versions, I would say anything past the 3.13.0-32.. If the memory doesn't fail me, at one point I had the 3.18.* something installed and was still being affected by it.

The problem with newer kernel versions is that the "full brightness" corresponds to something around 25-50% of the full brightness I get using the kernel 3.13.0-32.

(This last sentence might be a little bit confusing so later at night I'll try to take a couple of photos between the 3.13.0-32 and 3.13.0-48).

Thank you for all the help thus far,
All the best.

[Cameron Norman (cameronnemo)]

Do you have the brightness job logs for the new brightness file?

[Cameron Norman (cameronnemo)]

Also can you try the very latest, available at the same location?