Mageia forum

Hello everybody,

I have got the following problem: since I installed mageia3 on my laptop I was able to control brigtness using the default key shortcuts (fn+f5/f6), but after a particular update a couple months ago, I lost this function, the worst part is that I can't control the brightness either from the kde power applett. The OSD when hit the keys appears as before but does nothing and the screen is stuck at 100% brightness.

I tried to find something in the forums and some threads suggested plying with the grub boot options, as explained here:

https://wiki.archlinux.org/index.php/Backlight#ACPI and https://wiki.mageia.org/en/Mageia_3_Err ... top_issues

I think I have tried all options displayed there without result. Also booted with older installed kernels and problem persisted, maybe it has been an update in some kde component?

The laptop is using a CPU AMD E2 with a GPU radeon 7340 (it's an apu in fact). And the OS is mageia 3 x86_64 with all updates installed, current kernel 3.10.24-desktop-2.mga3. I want to remark that this feature worked since I installed mageia3 for first time it just disappeared with some update.

Thanks for your time.

Hi there,

what laptop is it exactly?

If you cannot change brightness directly as explained in the first link, it's probably not related to KDE updates.

Or did you only try the grub boot options? Please reread the first link, and post some of that output here like:

Code: Select all

ls /sys/class/backlight/
cat /sys/class/backlight/acpi_video0/brightness

The laptop exactly is a Sony VAIO SVE111B11M. I always omit it because this model is not very common, I never find problems/solutions for this particular laptop.

Regarding the brightness in command line I only tried after modifying grub, and folder /sys/class/backlight/ didn't had any content.

Now I have just tried without messing grub:

Code: Select all

[asimov@white ~]$ ls /sys/class/backlight/
acpi_video0@
[asimov@white ~]$ cat /sys/class/backlight/acpi_video0/brightness
12


Changing the value from terminal doesn't have any effect. By the way this value changes as well with the brigthness keys (which must be the usual behavior by the way).

Any suggestion on what to do next?

Thanks for the help.

EDIT
Lacked part of the terminal output.

I can also confirm I also have this problem with my ux31a

i used to be able to create custom keyboard shortcuts for it with

Using the "system setting" -> short cuts and gestures ->

global keyboard shortcuts -> kde-componant (kde-daemon) -> i set all the non working shortcuts to ALT-F{} versions of there FN key. this works fine for brightness, sleep, int/external monitor.

but this does not work any longer

if i operate the brightness up button, then reboot, the brightness changes, so the button is having an effect , just not being picked up by the kernel.

same with down.

used to work in mageia 2.

similar threads here

http://forums.gentoo.org/viewtopic-t-97 ... art-0.html





regards peter

I followed another threads advise and added acpi_osi="!Windows 2012" to menu.1st in /boot/grub.conf kernel line

and it fixed my backlight keys


well fixed is a wrong statment

it made them work, but they are really sluggish, but better than a poke in the eye with a sharp stick


EDIT, damm doing so kills volume up/down buttons, and others, but can live with that
as can adjust vol via kmix

not able to adjust brighness was a pain

regards peter

Just an update: Yesterday I tested mageia 4 RC and on the live DVD brightness buttons worked well.

I guess my only option is wait and upgrade to next version. Not a big deal I would have done it anyway.

Please mark the thread accordingly by editing the topic of the first post and prefix it by [DONE], thanks

I do not consider this [DONE] in anyway. An upgrade may be a solution for me but not for others with the same problem.

If you insist I will do it , I won't argue.

yes this is still a bug in the 3.10 kernel as far as im concerned

who wants to report it.

regards peter

I have booted with an older kernel 3.8.13.4-desktop-1.mga3 and it's the same.

So it's either an issue with the video driver or changed ACPI bootloader/kernel options.

The grub entry for that kernel has never been modified. I would blame the driver.

Then update only the driver and try again.

Point is you can blame whatever you want, but if you don't identify the cause of the issue your chances to effectively fix or workaround it are zilch.

I absolutely agree with you.

What I was trying to say is that I am going to research on that matter (driver issue) and as soon as I have any update write it here.

Understand that this is the computer I use at work. Not having brightness control is a minor issue. Messing with the graphic driver and screwing it all would be a huge inconvenience.

have you tried

acpi_osi="!Windows 2012" to menu.1st in /boot/grub.conf kernel line

as er my post several posts back

it fixed it for me, but also broke the volume.

regards peter

Tried wintpe solution without result.

Regarding the driver issue I'm running dkms-fglrx-13.250.18-0.1.mga3.nonfree, and it must be the problem. On the AMD webpage the latest drivers are numbered as 13.251, I'm not sure that problem will be solved.

The best solution I suggest it to switch to open source drivers ati/radeon, 3D acceleration works quite well, the downside is that brightness buttons stopped working and there are small graphical glitches, but since brightness can be controlled from the power applett and fglrx also had glitches I wont complain.

I will mark this as [DONE] if there is no inconvenience.

Thanks people for the help.