Bug 321310 - brightness on screen display is not shown when changing brightness via Fn keys
Summary: brightness on screen display is not shown when changing brightness via Fn keys
Status: RESOLVED UPSTREAM
Alias: None
Product: solid
Classification: Frameworks and Libraries
Component: powermanagement (show other bugs)
Version: 4.10.5
Platform: Ubuntu Linux
: NOR normal
Target Milestone: ---
Assignee: Dario Freddi
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2013-06-18 08:50 UTC by Gandalf Lechner
Modified: 2015-01-26 21:02 UTC (History)
3 users (show)

See Also:
Latest Commit:
Version Fixed In:


Attachments

Note You need to log in before you can comment on or make changes to this bug.
Description Gandalf Lechner 2013-06-18 08:50:51 UTC
when changing brightness via the slider accessible from the battery icon the on screen display works fine. In both cases, the brightness does change as it should.

I guess this might depend on the setup, so here is what I am using: 
Dell XPS13 "Sputnik" (ubuntu version) with BIOS A07, kernel 3.8.0-26-generic, kubuntu 13.04 fully updated



Reproducible: Always
Comment 1 Jim Jones 2013-09-27 17:47:29 UTC
same here on lenovo x220 and x230
Comment 2 Laurent 2014-01-26 15:41:20 UTC
Same here on Lenovo T440.

Just to clarify things:
- Brightness change via Fn keys: works, but there is no OSD and the slider in the battery widget is not updated.
- via widget slider: OSD is shown and of course the slider is "up-to-date" afterwards

Assumption: The Fn keys "bypass the way through KDE". Can it be that KDE checks if the brighness changing shortcuts are pressed? Because when I remap those shortcuts to "normal" ones (e.g. Ctrl + u etc...), everything works as expected. In that respect, there seem to be two solutions in my eyes:
1. watch the corresponding file in /proc
2. fix the problem at shortcut-level, so that the brightness Fn keys are recognized.

Additional Info: If I try to map Fn + BrightnessUp/Down to other actions, my system does NOT recognize that I just pressed Fn + BrightnessUp/Down and just keeps waiting. Even 'xev' does not register those keys.

Boot params: acpi_osi=
(yes, without anything behind the equality sign)

Regards
Comment 3 Laurent 2014-01-26 16:29:33 UTC
Hi all,
Fixed it for me on Lenovo T440p
https://bugs.kde.org/show_bug.cgi?id=323516#c24
Regards
Comment 4 Kai Uwe Broulik 2015-01-26 21:02:39 UTC
Most likely a driver/ACPI issue.