Linux Mint 12 (64bit), on an Acer Aspire 7730g. Upon every boot, the screen brightness is set very very low. Easily fixed via the function keys, but still a very annoying thing to do after every boot. Is there a way to set the brightness permanently?
NB: Interestingly, I had the same problem when Ubuntu was installed on the same laptop, so I’m a bit perplexed about how did this setting survive a complete OS reinstall?
dmesg output available here.
Another update: I don’t know if this is related, but every time I reboot, my wireless is off, bluetooth is on, and Num Lock is off; all three the exact opposite of what I want them to be. If this is not related, it may become another question.
Answers:
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Method 1
Your laptop should have /sys/class/backlight. For example, /sys/class/backlight/acpi_video0/brightness. You can write (echo) values to this file to adjust brightness.
cat /sys/class/backlight/acpi_video0/max_brightness > /sys/class/backlight/acpi_video0/brightness
This will set the brightness to max. Just put it in an init script on boot.
Method 2
my x120e’s brightness constantly changing bothers me as well. surprisingly (but not), when i ran
gksudo dmesg > boot.messages
and opened boot.messages in a text editor, i noticed this message:
[Firmware Bug]: ACPI: No _BQC method, cannot determine initial brightness
multiple times, as well as some interesting others. paste that into Google and you’ll find Cannibal’s Candy [wordpress] – who provides an in-depth look at ACPI and a method for universally setting the screen brightness (+ so much more):
DSDT editing: Put an end to your ACPI woes
yep, prepare your mind to be blown. i’m working through CC’s post right now, but thought i would share. best of luck!
running Linux Mint Debian (amd64) on a Thinkpad x120e
All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0