Arch Linux

rgomes

Member

Registered: 2013-11-15

Posts: 43

Backlight key presses not detected, OPTIMUS, wiki didn't help

I am using a Razer Blade 14" with linux-ck kernel (although I have tested in the main kernel and the issue remains).
The keyboard brightness settings keys are not detected by X at all (using xev reports no keycodes when I press them).
However, the driver is getting that information. And in the same type as other function keys (such as sound up/down - which are detected correctly).
I know this because, while investigating the workings of the touchpad, I ran the razer-test script found in:
http://fxchip.net/RazerBlade/
(slightly modified because the device ID is 0x011D in the 14").
It distinguishes normal key presses from Macro Keys. Function keys in this laptop are macro keys. When pressing volume down, I get the following report:

Macro keys: Razer Extra Buttons:
  Extra key: FN
04 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Macro keys: 02 ea 00 00
Macro keys: 02 00 00 00
Macro keys: Razer Extra Buttons:
04 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

When pressing brightness up/down, I get the following report:

04 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Macro keys: 02 70 00 00
Macro keys: 02 00 00 00
Macro keys: 02 6f 00 00
Macro keys: 02 00 00 00
Macro keys: Razer Extra Buttons:
04 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

(note that the last part just signals that I let go of the FN key)

My idea was to try to find the keycodes through xev and then map them manually. However, this was unsuccessful since xev reports no input when I press brightness up/down (while volume up/down works).
This is where I'm lost - the keyboard drivers seems to just be ignoring them.

Any help appreciated . Let me know what I can post if it's of any help!
Cheers,
Rodrigo

EDIT:
My laptop uses optimus hardware, and I'm using the integrated Intel Graphics card.
I have tried all the methods in the wiki but none of them worked:
https://wiki.archlinux.org/index.php/backlight#Overview
https://wiki.archlinux.org/index.php/In … ter_resume.

It's also worth noting that I do have control over the backlight with software - the FN+F8/F9 key bindings are the ones that are just completely ignored by the driver.

Last edited by rgomes (2013-11-22 18:47:57)

socials

Member

Registered: 2013-11-15

Posts: 27

Re: Backlight key presses not detected, OPTIMUS, wiki didn't help

Try setting

acpi_backlight=vendor

in your kernel parameters.

rgomes

Member

Registered: 2013-11-15

Posts: 43

Re: Backlight key presses not detected, OPTIMUS, wiki didn't help

Try setting

acpi_backlight=vendor

in your kernel parameters.

I tried doing that, but it didn't work.
I think it's because that is what you should do if the backlight control doesn't work (which it does - I can use software to change the screen's backlight).
What doesn't work is the FN+F8/F9 keyboard shortcuts.
This isn't a big issue because I set it up to have a different shortcut to control brightness, but it would be nice to explore what's causing this - the key is being sent through, but completely ignored by the driver (as I said, xev doesn't even detect it).

WonderWoofy

Member

From: Los Gatos, CA

Registered: 2012-05-19

Posts: 8,414

Re: Backlight key presses not detected, OPTIMUS, wiki didn't help

Optimus, right?  It would have been nice to give at least a broad overview of your graphics hw rather than making potential help click on a link. 

In any case, if you are using the integrated Intel card, you should look over the wiki on Intel graphics, as there are a few solutions there to work around the new windows 8 way of handling the backlight.  Personally I am able to use acpi_osi="!Windows 2012", but this doesn't seem to consistently work for everyone with Intel graphics (which is why you should reference the wiki).

rgomes

Member

Registered: 2013-11-15

Posts: 43

Re: Backlight key presses not detected, OPTIMUS, wiki didn't help

I'm sorry I didn't specify the graphical hardware, I thought it wouldn't interfere with the keyboard, it seems I was mistaken. I have edited the title and added a mention to that in the initial post.
However, I just tried all the work arounds, and none of them worked for me (acpi_backlight=vendor, acpi_osi=Linux or "!Windows 2012" and adding the xorg configuration file).

WonderWoofy

Member

From: Los Gatos, CA

Registered: 2012-05-19

Posts: 8,414

Re: Backlight key presses not detected, OPTIMUS, wiki didn't help

Okay... fresh out of ideas then.  Sorry.  Typically these backlight control issues are in fact a graphics issue lately because of the new way that windows handles things.  Of course, it may not be standard, but if that is how windows does it, by golly, that is what the industry will do!

artoo

Member

Registered: 2012-09-04

Posts: 175

Website

Re: Backlight key presses not detected, OPTIMUS, wiki didn't help

Same problem here.
Nvidia gt 720m & intel HD4000, lenovo ideapad G500s, core i5

While it works out on ubuntu with prop. nvidia driver, it does not with arch.

I use on ubuntu

acpi_backlight=vendor  acpi_osi="!Windows 2012"

but same doesn't do the trick on arch.

I won't even get any graphical login on arch.
I use the xrandr addition in ~.xinitrc. I tried to put it system wide, but no success.

maxo

Member

Registered: 2011-11-26

Posts: 5

Re: Backlight key presses not detected, OPTIMUS, wiki didn't help

Hey. If you aren't using the nvidia graphics card then this works on mine.

Edit the /etc/X11/xorg.conf.d/20-intel.conf by adding

 
Option        "Backlight"     "intel_backlight"  

Xorg normally automatically selects the backlight device. On mine it ued acpi_video0 instead of intel_backlight.

Hope that helps!

Last edited by maxo (2013-12-13 11:19:23)

rgomes

Member

Registered: 2013-11-15

Posts: 43

Re: Backlight key presses not detected, OPTIMUS, wiki didn't help

Hey. If you aren't using the nvidia graphics card then this works on mine.

Edit the /etc/X11/xorg.conf.d/20-intel.conf by adding

 
Option        "Backlight"     "intel_backlight"  

Xorg normally automatically selects the backlight device. On mine it ued acpi_video0 instead of intel_backlight.

Hope that helps!

I had already tried that but it didn't work (it's on the wiki).
Thanks for the tip though.

artoo

Member

Registered: 2012-09-04

Posts: 175

Website

Re: Backlight key presses not detected, OPTIMUS, wiki didn't help

Hey. If you aren't using the nvidia graphics card then this works on mine.

Edit the /etc/X11/xorg.conf.d/20-intel.conf by adding

 
Option        "Backlight"     "intel_backlight"  

Xorg normally automatically selects the backlight device. On mine it ued acpi_video0 instead of intel_backlight.

Hope that helps!

Thanks, but the challenge is, to get nvidia prop. drivers working.

I think, I tracked the problem down to some backlight issue, probably a firmware issue with the laptop model.

On ubunutu, ideapad backlight modules gets loaded, on arch, it uses the intel-bl. As it stands to reason, backlight settings are too dim when starting X.
I am about to test nvidia-bl from AUR.