Brightness adjustment keys will not work

[joeyc]

Hi there,

OS: Mageia 2
Machine: Toshiba 550D netbook

When I first installed Mageia 2 I was able to adjust the screen brightness through the GUI or through shortcut keys. Now I am unable to do either and am not sure how to troubleshoot this. I have tried googling the issue and I have tried restarting many times. Now I am out of ideas

Could someone please tell me where to start?

[oj]

Did this start with a kernel update? If you have older kernels available to boot into, try one of those and see if the keys are working there. (select an older kernel from the initial boot splash screen)

[joeyc]

Hi oj - have tried a few of the previous kernels on the splash page and can still no longer adjust screen brightness

[joeyc]

Any other ideas?

[oj]

Well, you could try the "linus' kernel. That is packaged 'as is' the way the upstream developers set it up. It's not 'optimized' to integrate with Mageia, it's quite generic and a bit more up-to-date than the 'official' kernel releases.

I had this very problem with one of my laptops and using the linus kernel fixed it.

Another thing I would do is boot from the live CD/DVD and check to see if the keys work in that environment, just to confirm the problem is something in my installation of the hard drive. (rather than the unlikely coincidence that the key has physically quit working)

[madeye]

I had a similar problem with my laptop, and I was able to solve it by adding the following to the kernel line in the bootloader

Code: Select all

acpi_osi=Linux acpi_backlight=vendor

Some info I found at https://wiki.archlinux.org/index.php/Backlight#ACPI and https://wiki.mageia.org/en/Mageia_3_Errata#Laptop_issues