Bug 334321

Summary:	KDM does not initialize keyboard backlight support properly
Product:	[Unmaintained] kdm	Reporter:	Maxim Vasilyev <mxmvasilyev0>
Component:	general	Assignee:	kdm bugs tracker <kdm-bugs-null>
Status:	RESOLVED INTENTIONAL
Severity:	normal	CC:	acimmarusti, anonymous-2015, letsyl, mihais23, tsujan2000
Priority:	NOR
Version:	4.11.5
Target Milestone:	---
Platform:	Debian testing
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description Maxim Vasilyev 2014-05-04 10:39:26 UTC

KDM does not initialize support for keyboard backlight at first attempt. LightDM works fine though. There's a somewhat related thread on KDE forum by Jens Reuterberg:
http://forum.kde.org/viewtopic.php?f=66&t=118366

Steps to reproduce:
1. Log in using KDM
2. See that keyboard backlight is not detected at all, and cannot be changed nor by power management GUI, neither by Fn keys (but can be changed by "cat x > /sys/devices/platform/asus-nb-wmi/leds/asus::kbd_backlight/brightness"
3. Log out and log in using KDM
4. Everything works fine

Actual result:
Keyboard backlight is not detected and thus can't be changed, unless user relogins.

Expected result:
Keyboard backlight is functioning and adjustable upon session startup

Rerproductible:
Always

Additional info:
LightDM works perfect, backlight starts working right after logging in. Tested on Asus Zenbook UX21A. There's a related thread on KDE forum by Jens Reuterberg about laptop from the same series (UX31VD):
http://forum.kde.org/viewtopic.php?f=66&t=118366

Comment 1 anonymous-2015 2014-05-21 09:54:34 UTC

I use Debian sid with KDE 4.13.1 and I face the same issue. It annoys me a lot! I didn't try other DMs, though. My laptop is ASUS N750.

Comment 2 Andres Cimmarusti 2014-07-15 20:06:06 UTC

I have the same issue, also running Debian testing with KDE 4.13.x.
My laptop is an Asus G55VW.
I have narrowed the issue and found a workaround. A summary is available from:

https://bugs.debian.org/754200

or

https://forum.kde.org/viewtopic.php?f=63&t=121045

I haven't tried lightdm, but the bottom line is KDM does NOT start upowerd early enough for powerdevil to become aware of the keyboard brightness capabilities.
The workaround is to put a script in ~.kde/env/ calling qdbus to start upowerd.

Comment 3 Tsu Jan 2015-02-25 11:38:44 UTC

Exactly the same issue with KDE-4.14.2, in Debian Testing/Unstable installed on Asus G56JK. Andres's workaround works for me (an sh script in ~/.kde4/env/, which runs "qdbus --system org.freedesktop.UPower"). I haven't tried other DMs.

Comment 4 Sylvain Leterreur 2015-04-11 22:54:33 UTC

Same issue with a macbook pro late 2013 running fedora 21 (with SDDM as login manager). Login out and login in brings the keyboard backlight support back.

The keyboard backlight keys used to work with a previous version of kde (unfortunately I can't tell exactly which version as I didn't notice when the issue started to appear)

Comment 5 Sylvain Leterreur 2015-04-12 17:29:40 UTC

I double checked, and my fedora 21 still use kdm as login manager

Comment 6 Maxim Vasilyev 2016-08-28 21:27:36 UTC

Since kdm has been discontinued, I mark this bug RESOLVED WONFIX.