Bug 905116

Summary:	kde-plasma/powerdevil-5.27.4.1 lost the ability to change backlight
Product:	Gentoo Linux	Reporter:	Chris Henhawke <chris>
Component:	Current packages	Assignee:	Gentoo Linux bug wranglers <bug-wranglers>
Status:	RESOLVED NEEDINFO
Severity:	normal
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
Whiteboard:
Package list:		Runtime testing required:	---

Description Chris Henhawke 2023-04-26 12:49:36 UTC

Hello,

When my laptop starts up, the brightness is set to around 50%, which would increase to 100% when I log into KDE, change to 70% when not on AC, and drop lower when battery is critical.  After the recent round of KDE upgrades, this functionality seems to have stopped working.

[ebuild   R    ] kde-plasma/powerdevil-5.27.4.1:5::gentoo  USE="handbook wireless (-brightness-control) -caps -debug" 0 KiB
[ebuild   R   ~] app-misc/ddcutil-1.3.0:0/4::gentoo  USE="X user-permissions -drm -usb-monitor" VIDEO_CARDS="-nvidia" 0 KiB


Changing the brightness-control USE flag seems to go ignored by portage, it's always disabled.  Installing ddcutil manually doesn't seem to help.

Reproducible: Always

Steps to Reproduce:
1. Install older KDE
2. Upgrade KDE
Actual Results:  
Get stuck with a dark screen in KDE

Expected Results:  
Working brightness controls

cat /sys/class/backlight/intel_backlight/max_brightness > /sys/class/backlight/intel_backlight/brightness still seems to work.

Comment 1 Chris Henhawke 2023-04-26 19:42:15 UTC

And now all of a sudden its working, all I did was reboot again...  weird.

Comment 2 Andreas Sturmlechner gentoo-dev

2023-04-27 10:34:24 UTC

Always restart your session after upgrades before filing bugs.

brightness-control use flag is for direct control of the panel which almost no one does, it is stable-masked.

Comment 3 Chris Henhawke 2023-04-27 10:36:08 UTC

Hello, I had rebooted, twice infact.  I can't explain why it wasn't working.  But thanks for the reply.