Bug 468547

Summary:	Second monitor have no hdmi signal after waking from sleep
Product:	[Plasma] kwin	Reporter:	Andrew Shark <ashark>
Component:	multi-screen	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED UPSTREAM
Severity:	major	CC:	nate, notmart, xaver.hugl
Priority:	NOR	Keywords:	regression
Version First Reported In:	5.27.4
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	drm_info before sleep (both monitors working) drm_info after sleep (hdmi monitor not working)

Description Andrew Shark 2023-04-15 22:06:30 UTC

I have several monitors. One monitor is connected with displayport, second monitor is connected with hdmi. The problem appears after sleep. The hdmi monitor stays in stand by mode (waiting for signal).

STEPS TO REPRODUCE
1. Turn on PC. Both monitors show picture.
2. Turn PC to sleep.
3. Wake up PC.

OBSERVED RESULT
The picture is only shown on displayport monitor. On hdmi monitor there is no signal.

EXPECTED RESULT
Picture should be shown on both monitors.

This is a regression. It worked normally previously. Unfortunately, I do not know exactly in which version it was broken. Probably a month ago.

SOFTWARE/OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 5.27.4
KDE Frameworks Version: 5.105.0
Qt Version: 5.15.9
Graphics Platform: Wayland
Graphics Processor: AMD Radeon RX 580 Series

ADDITIONAL INFORMATION
There are workarounds:
1) Turn off, then turn on the monitor by its power button.
2) Disable, then enable the hdmi monitor in system settings.

Comment 1 Zamundaaa 2023-04-17 16:52:17 UTC

Please attach the output of drm_info (https://gitlab.freedesktop.org/emersion/drm_info), once for when the monitor works, and once for when it doesn't get a signal

Comment 2 Andrew Shark 2023-04-17 19:31:42 UTC

Created attachment 158173 [details]
drm_info before sleep (both monitors working)

Comment 3 Andrew Shark 2023-04-17 19:32:20 UTC

Created attachment 158174 [details]
drm_info after sleep (hdmi monitor not working)

Comment 4 Andrew Shark 2023-04-17 19:34:18 UTC

It is some kind unstable. This time after first sleep the hdmi mon worked normal. Then after second sleep it was not working. Then after third sleep it was working again.

Comment 5 Zamundaaa 2023-04-18 12:40:44 UTC

The kernel says both outputs are enabled, so this is a driver bug. It's most likely the same as https://gitlab.freedesktop.org/drm/amd/-/issues/2497, so please add your information there