Bug 467910

Summary:	Keyboard brightness controls turn off backlight completely when reaching 0%
Product:	[Unmaintained] Powerdevil	Reporter:	Yeshi <nikolai.bjerke.sakariassen2>
Component:	general	Assignee:	Plasma Bugs List <plasma-bugs>
Status:	RESOLVED DUPLICATE
Severity:	minor	CC:	me, nate
Priority:	NOR
Version First Reported In:	5.26.5
Target Milestone:	---
Platform:	Manjaro
OS:	Linux
Latest Commit:	https://invent.kde.org/plasma/powerdevil/-/commit/e1e74f37ea6ba4d3450ae79ede25a7cac1dd9a84	Version Fixed In:	6.0
Sentry Crash Report:

Description Yeshi 2023-03-29 01:50:37 UTC

Changing the backlight to 0% turns the backlight off entirely, rather than setting a low brightness amount.
However, changing the brightness to 0% through the battery widget does not have the same problem.
I would suggest keeping this bugged behavior as a setting somewhere, as it might be nice to have in some cases.

SOFTWARE/OS VERSIONS
Kernel: 6.1.19-1-MANJARO
KDE Plasma Version: 5.26.5
KDE Frameworks Version: 5.103.0
Qt Version: 5.15.8

Comment 1 Nate Graham 2023-04-03 22:25:06 UTC

This is an Intel GPU driver bug which is fixed in the latest version of Mesa and also worked around in Plasma 5.27.

Comment 2 Nate Graham 2023-08-13 17:35:07 UTC

Git commit e1e74f37ea6ba4d3450ae79ede25a7cac1dd9a84 by Nate Graham.
Committed on 13/08/2023 at 19:29.
Pushed by ngraham into branch 'master'.

Make minimum screen brightness not always be 0

With some drivers, a value of 0 disables the screen backlight
completely, which is almost certainly not what the user wanted. The
Battery & Brightness widget has logic to handle this and instead make
1 the minimum brightness for screens. But Powerdevil does not, and as a
result, the behaviors differ between adjusting the brightness using the
widget and using the keyboard's "brightness down" key. This is
inconsistent and weird.

This commit unifies the behaviors by adding logic to Powerdevil to match
what the widget does.

Arguably this is working around a driver bug, but insisting that all
graphics driver bugs be fixed is not practical due to their diversity
and frequent regressions. And the Battery & Brightness widget already
has such a workaround to prevent users whose graphics drivers don't
work as they should from experiencing this issue, so not doing the same
here is inconsistent.
FIXED-IN: 6.0

M  +4    -4    daemon/powerdevilbrightnesslogic.cpp
M  +14   -0    daemon/powerdevilbrightnesslogic.h
M  +6    -0    daemon/powerdevilscreenbrightnesslogic.cpp
M  +1    -0    daemon/powerdevilscreenbrightnesslogic.h

https://invent.kde.org/plasma/powerdevil/-/commit/e1e74f37ea6ba4d3450ae79ede25a7cac1dd9a84

Comment 3 Nate Graham 2023-08-13 19:10:11 UTC


*** This bug has been marked as a duplicate of bug 430439 ***