Brightness control doesn't seem to work on a Toshiba Satellite M115 laptop

Question

I have Ubuntu 12.04 LTS on a Toshiba Satellite M115 laptop. The brightness control doesn't seem to work with the "brightness and lock" setting or fn+f6 and fn+f7 (which usually works in Windows). How can I adjust the brightness and/or access different power settings, so my computer isn't running on full power all the time?

Solution 1

I resolved my own issue by updating my BIOS. I did this by entering my model of Toshiba at http://www.csd.toshiba.com/cgi-bin/tais/support/ and downloading the latest BIOS. Be sure to read all documentation that comes with the download before updating. https://help.ubuntu.com/community/ReportingBugs says "Outdated and buggy BIOS firmware is a common cause of a variety of hardware issues (ex. intermittent wireless, suspend not working, and certain keys on keyboard not working correctly, kernel panics after plugging USB drive in)."

Solution 2

I am not familiar with your particular model, but you can try some of these 'solutions'.

Add acpi_backlight=vendor to grub:

Open terminal (Ctrl+Alt+T) and type:

gksudo gedit /etc/default/grub

You will find this line in the new opened window:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

Change it to:

Example:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"

Note your entry may be different - only add the acpi_backlight=vendor.

After doing that, do:

sudo update-grub

---

If that does not get the Fn+F6 and Fn+F7 keys working, you can do this via the system settings as seen below:

Solution 3

Worked for Toshiba Satellite L-750

open unity search and type "additional drivers" select: using NVIDIA binary driver -version .... apply changes and reboot

Comments

[cprofitt]

the bug is for buttons that stop working after a suspend.

[thorstorm]

Yes it's true, but I've seen a similar problem on another laptop (no brightness control at all) where the workaround works as well.

[cprofitt]

this work around is the command line version of using system settings though; correct?

[thorstorm]

…when neither system settings nor shortcut keys work.

[Temple Ontherat]

I tried both of your suggestions and neither worked. Thanks anyway.

[Temple Ontherat]

I tried your workaround and it said the command had an invalid argument. Not sure what that means. Thanks.

[thorstorm]

Do you have a /sys/class/backlight/intel_backlight/brightness file?

[Temple Ontherat]

Yes. After having done a little research, I'm beginning to think that my particular brightness/power management issue is related to the Phoenix Bios in my model of Toshiba laptop, which I hear is not a true Toshiba Bios.

[Temple Ontherat]

Just updated the BIOS. Screen brightness feature in Ubuntu is now working. Thanks for your help. I think my issue is resolved.

[cprofitt]

@TempleOntherat - there may be something more significant than the Fn keys now working then. You may want to file a bug.

[Temple Ontherat]

@cprofitt- Sorry, I'm new to Linux and Ubuntu. Would you post a link where I could read how to do that?

[Temple Ontherat]

help.ubuntu.com/community/ReportingBugs says that before a person using Ubuntu files a report they should update their BIOS. I guess I should have done that first. Again, new at this.

[cprofitt]

@TempleOntherat - good find... if that does not help let me know. If you have IRC I can walk you through reporting a bug.

[thorstorm]

I'm glad it worked. Why don't you answer your own question to help others having similar problems?