Bug 511054

Summary:	DDC/CI brightness is not working when HDR is enabled
Product:	[Plasma] plasmashell	Reporter:	Błażej Szczygieł <mumei6102>
Component:	Power management & brightness	Assignee:	Plasma Bugs List <plasma-bugs-null>
Status:	RESOLVED DUPLICATE
Severity:	normal	CC:	kdedev
Priority:	NOR
Version First Reported In:	6.4.5
Target Milestone:	1.0
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Błażej Szczygieł 2025-10-24 21:39:02 UTC

SUMMARY
Brightness is managed by software when HDR is enabled even if DDC/CI checkbox is checked.

STEPS TO REPRODUCE
1. Make sure monitor supports DDC/CI brightness control (also in HDR mode).
2. Turn on HDR and make sure "Control hardware brightness with DDC/CI" is enabled.
3. Change brightness and press "Apply".

OBSERVED RESULT
Monitor hardware brightness is not changed, brightness is changed in kwin compositor only.

EXPECTED RESULT
Monitor hardware brightness is changed according to the slider (because it's supported) and software brightness is set to 100%.

SOFTWARE/OS VERSIONS
KDE Plasma Version: 6.5.0
KDE Frameworks Version: 6.19
Qt Version: 6.10

Comment 1 TraceyC 2025-10-27 22:54:16 UTC

Thanks for the bug report. This looks like bug 486072. I'll merge this in with that report. Please follow the other report for updates. Thanks!

*** This bug has been marked as a duplicate of bug 486072 ***