Bug 504337

Summary: HDR started getting dark randomly
Product: [Plasma] kwin Reporter: dougg0k
Component: colour-managementAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED NOT A BUG    
Severity: normal CC: linux, nate, ty.pixelplane, xaver.hugl
Priority: NOR    
Version First Reported In: 6.2.5   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description dougg0k 2025-05-16 14:58:43 UTC
SUMMARY
Not sure why, but HDR started getting darker randomly, where sometimes it does work normally, before it worked normally. I've seen it happen straight after a boot with it being already enabled, and happen by me enabling it manually. When it does, it continously does, even if I turn back off and on again.

It's unusable when it happens.

STEPS TO REPRODUCE
1. Have HDR enabled

OBSERVED RESULT
Much darker screen with HDR On even though being on brightness 100%.

EXPECTED RESULT
To work normally.

SOFTWARE/OS VERSIONS
KDE Plasma Version: 6.3.5
KDE Frameworks Version: 6.14.0
Qt Version: 6.9.0
Graphics Platform: Wayland
Graphics Processor: NVIDIA GeForce RTX 3080 Ti

ADDITIONAL INFORMATION
I checked with screenshots, it stay normal in them. It doesnt make sense to be the monitor acting up, as it is working normally without it and it is in the latest firmware. It's a PG27AQN.
Comment 1 dougg0k 2025-05-16 15:05:08 UTC
I gotta also say that sometimes when switching it up, the brightness even though in 100%, stay a bit darker, even with HDR disabled, there might be bugs around it.

I dont see any relevant errors in the logs, but will add it here what is there from KDE.


systemd[3207]: dbus-:1.2-org.kde.KSplash@0.service: Failed with result 'exit-code'.
kwalletd6[3921]: g_dbus_proxy_get_object_path: assertion 'G_IS_DBUS_PROXY (proxy)' failed
kwin_wayland[3283]: kf.windowsystem: static bool KX11Extras::mapViewport() may only be used on X11
sudo[4660]:  user : a password is required ; TTY=pts/1 ; PWD=/home/user ; USER=root ; COMMAND=/usr/bin/true
kwin_wayland[3283]: kf.windowsystem: static bool KX11Extras::mapViewport() may only be used on X11
kwin_wayland[3283]: kwin_core: XCB error: 3 (BadWindow), sequence: 941, resource id: 20971547, major code: 129 (SHAPE), minor code: 6 (Input)
kioworker[4891]: kf.config.core: "KConfigIni: In file /home/user/.local/share/Trash/info/.maccel.o.d.trashinfo, line 1:" Invalid entry (missing '=')
plasmashell[3405]: kf.runner: Error requesting matches; calling "org.kde.runners.baloo"  : "org.freedesktop.DBus.Error.NotSupported" ""
plasmashell[3405]: kf.runner: Error requesting matches; calling "org.kde.runners.baloo"  : "org.freedesktop.DBus.Error.NotSupported" ""
plasmashell[3405]: kf.runner: Error requesting matches; calling "org.kde.runners.baloo"  : "org.freedesktop.DBus.Error.NotSupported" ""
kwin_wayland[3283]: kwin_xwl: Could not create a source from 0x735c60003190 0
kwin_wayland[3283]: qt.dbus.integration: QDBusConnection: couldn't handle call to Teardown, no slot matched
kwin_wayland[3283]: qt.dbus.integration: QDBusConnection: couldn't handle call to Teardown, no slot matched
baloorunner[4948]: qt.dbus.integration: QDBusConnection: couldn't handle call to Teardown, no slot matched
baloorunner[4948]: qt.dbus.integration: QDBusConnection: couldn't handle call to Teardown, no slot matched
kwin_wayland[3283]: qt.dbus.integration: Could not find slot Krunner1Adaptor::Teardown
baloorunner[4948]: qt.dbus.integration: Could not find slot Krunner1Adaptor::Teardown
plasmashell[3405]: kf.runner: Error requesting matches; calling "org.kde.runners.baloo"  : "org.freedesktop.DBus.Error.NotSupported" ""
plasmashell[3405]: kf.runner: Error requesting matches; calling "org.kde.runners.baloo"  : "org.freedesktop.DBus.Error.NotSupported" ""
Comment 3 dougg0k 2025-05-16 15:40:47 UTC
I noticed that when the brightness stay a bit darker, outside the main bug, with is HDR OFF, if I change HDR to ON and OFF again, that is fixed to the proper brightness.
Comment 4 Zamundaaa 2025-05-19 15:58:17 UTC
Does the monitor allow you to change brightness in its own menu? If so, is that value different when the screen is so dark?
Comment 5 dougg0k 2025-05-19 16:32:23 UTC
Auto HDR Brightness is disabled and I only see Peak White (nits) which is greyed out, with HDR ON. 

The brightness option is only available when HDR are OFF. So, no?!
Comment 6 Zamundaaa 2025-05-19 16:47:02 UTC
hmm, then it probably is something directly in KWin. When the screen is dark the next time, please attach the output of
> kscreen-doctor -o
Comment 7 dougg0k 2025-05-19 16:50:44 UTC
Will do.

Just to have the info here. This is when HDR is correctly working in the Output that the issue happens.

โฏ kscreen-doctor -o                                                                                                                                                                                         12:40:20
Output: 1 DP-2
        enabled
        connected
        priority 1
        DisplayPort
        Modes:  1:2560x1440@60!  2:2560x1440@360*  3:2560x1440@240  4:2560x1440@144  5:2560x1440@120  6:2560x1440@100  7:2368x1332@360  8:2368x1332@240  9:1920x1080@360  10:1920x1080@240  11:1920x1080@120  12:1024x768@60  13:800x600@60  14:640x480@60
        Geometry: 0,0 2560x1440
        Scale: 1
        Rotation: 1
        Overscan: 0
        Vrr: Never
        RgbRange: unknown
        HDR: enabled
                SDR brightness: 650 nits
                SDR gamut wideness: 20%
                Peak brightness: 673 nits
                Max average brightness: 400 nits
                Min brightness: 0.0994 nits
        Wide Color Gamut: enabled
        ICC profile: /home/user/.dotfiles/configs/pg27aqn_color_profile.icm
        Color profile source: ICC
        Color power preference: prefer efficiency and performance
        Brightness control: supported, set to 60% and dimming to 100%
Comment 8 Bug Janitor Service 2025-06-03 03:47:59 UTC
๐Ÿ›๐Ÿงน โš ๏ธ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

Thank you for helping us make KDE software even better for everyone!
Comment 9 dougg0k 2025-06-17 22:19:44 UTC
The issue just happened again after coming back from being AFK / log in.

It's the same, nothing changed. This week I reduced a few settings on brightness but it's probably unrelated, as it have been working fine.

โฏ kscreen-doctor -o                                                                                                                                                                                                                                                                                                                                                                 
Output: 1 DP-2
        enabled
        connected
        priority 1
        DisplayPort
        Modes:  1:2560x1440@60!  2:2560x1440@360*  3:2560x1440@240  4:2560x1440@144  5:2560x1440@120  6:2560x1440@100  7:2368x1332@360  8:2368x1332@240  9:1920x1080@360  10:1920x1080@240  11:1920x1080@120  12:1024x768@60  13:800x600@60  14:640x480@60
        Geometry: 0,0 2560x1440
        Scale: 1
        Rotation: 1
        Overscan: 0
        Vrr: Never
        RgbRange: unknown
        HDR: enabled
                SDR brightness: 500 nits
                SDR gamut wideness: 10%
                Peak brightness: 673 nits
                Max average brightness: 400 nits
                Min brightness: 0.0994 nits
        Wide Color Gamut: enabled
        ICC profile: /home/user/.dotfiles/configs/pg27aqn_color_profile.icm
        Color profile source: ICC
        Color power preference: prefer efficiency and performance
        Brightness control: supported, set to 50% and dimming to 100%
Comment 10 dougg0k 2025-06-17 22:26:07 UTC
The only logs in the time between that it happened.

There is a gsync issue, but I am not using gsync/vrr on this monitor, it's set to never. And I have plenty of env vars attempting to disable it. Since I use it disabled in X11, ULMB2 works there. 

But it is not truly disabled in wayland atm, since nvidia are still working to have ULMB2 working on Wayland, if ULMB2 are enabled, VRR are surely disabled. Not sure if related.

jun 17 18:00:18 desktop-pc kernel: kauditd_printk_skb: 3073 callbacks suppressed
jun 17 19:13:34 desktop-pc kernel: nvidia-modeset: WARNING: GPU:0: Asustek Computer Inc ROG PG27AQN (DP-2): Failed to initialize G-SYNC
jun 17 19:13:34 desktop-pc kernel: kauditd_printk_skb: 129 callbacks suppressed
jun 17 19:13:40 desktop-pc kernel: kauditd_printk_skb: 977 callbacks suppressed
jun 17 19:13:42 desktop-pc kscreenlocker_greet[178623]: qt.qpa.wayland: Could not create EGL surface (EGL error 0x3003)
jun 17 19:13:42 desktop-pc kscreenlocker_greet[178623]: Failed to write to the pipe: Bad file descriptor.
jun 17 19:13:52 desktop-pc kernel: kauditd_printk_skb: 1041 callbacks suppressed
jun 17 19:13:53 desktop-pc org_kde_powerdevil[3446]: No traced function stack for current thread
jun 17 19:13:53 desktop-pc org_kde_powerdevil[3446]: [  3446] /dev/i2c-3: Checking EDID succeeded after 2 tries (G)
jun 17 19:13:53 desktop-pc org_kde_powerdevil[3446]: [  3446] busno=3. Monitor apparently returns -EIO for unsupported features. This cannot be relied on.
jun 17 19:13:55 desktop-pc kioworker[179330]: kf.config.core: "KConfigIni: In file /home/user/.local/share/Trash/info/.maccel.o.d.trashinfo, line 1:" Invalid entry (missing '=')
jun 17 19:14:00 desktop-pc kernel: kauditd_printk_skb: 1146 callbacks suppressed
jun 17 19:14:06 desktop-pc kernel: kauditd_printk_skb: 1424 callbacks suppressed
jun 17 19:14:25 desktop-pc plasmashell[3402]: kf.runner: Error requesting matches; calling "org.kde.runners.baloo"  : "org.freedesktop.DBus.Error.NotSupported" ""
jun 17 19:14:26 desktop-pc kernel: kauditd_printk_skb: 956 callbacks suppressed
jun 17 19:14:26 desktop-pc keepassxc[179858]: kf.i18n: KLocalizedString: Using an empty domain, fix the code. msgid: "Save All" msgid_plural: "" msgctxt: "@action:button"
jun 17 19:14:26 desktop-pc keepassxc[179858]: kf.i18n: KLocalizedString: Using an empty domain, fix the code. msgid: "&Yes" msgid_plural: "" msgctxt: "@action:button"
jun 17 19:14:26 desktop-pc keepassxc[179858]: kf.i18n: KLocalizedString: Using an empty domain, fix the code. msgid: "Yes to All" msgid_plural: "" msgctxt: "@action:button"
jun 17 19:14:26 desktop-pc keepassxc[179858]: kf.i18n: KLocalizedString: Using an empty domain, fix the code. msgid: "&No" msgid_plural: "" msgctxt: "@action:button"
jun 17 19:14:26 desktop-pc keepassxc[179858]: kf.i18n: KLocalizedString: Using an empty domain, fix the code. msgid: "No to All" msgid_plural: "" msgctxt: "@action:button"
jun 17 19:14:26 desktop-pc keepassxc[179858]: kf.i18n: KLocalizedString: Using an empty domain, fix the code. msgid: "Abort" msgid_plural: "" msgctxt: "@action:button"
jun 17 19:14:26 desktop-pc keepassxc[179858]: kf.i18n: KLocalizedString: Using an empty domain, fix the code. msgid: "Retry" msgid_plural: "" msgctxt: "@action:button"
jun 17 19:14:26 desktop-pc keepassxc[179858]: kf.i18n: KLocalizedString: Using an empty domain, fix the code. msgid: "Ignore" msgid_plural: "" msgctxt: "@action:button"
jun 17 19:14:27 desktop-pc keepassxc[179858]: qt.qpa.wayland: Wayland does not support QWindow::requestActivate()
jun 17 19:14:27 desktop-pc keepassxc[179858]: qt.qpa.wayland: Wayland does not support QWindow::requestActivate()
jun 17 19:14:32 desktop-pc kernel: kauditd_printk_skb: 48 callbacks suppressed
jun 17 19:14:50 desktop-pc kernel: kauditd_printk_skb: 6 callbacks suppressed
jun 17 19:15:20 desktop-pc kernel: kauditd_printk_skb: 11 callbacks suppressed
jun 17 19:15:57 desktop-pc kernel: kauditd_printk_skb: 1376 callbacks suppressed
jun 17 19:16:00 desktop-pc sudo[188426]:  user : a password is required ; TTY=pts/1 ; PWD=/home/user ; USER=root ; COMMAND=/usr/bin/true
jun 17 19:16:00 desktop-pc kwin_wayland[3278]: kf.windowsystem: static bool KX11Extras::mapViewport() may only be used on X11
Comment 11 dougg0k 2025-06-17 22:34:00 UTC
Ok, after the issue, now, I logged out, and in the log in screen, it was fine. Correct.

I then changed to X11, and logged back in, it was working correctly.

Then I logged out again and logged back to Wayland, and the issue is back / continued. 

I regenerated the logs, there is no mentioned of gsync at this point.
Comment 12 dougg0k 2025-06-17 22:40:29 UTC
After a restart, the issue was back, then turning HDR off, fixed the issue. However if turning it back ON, the issue is back. As mentioned before. As I did the reboot, usually there is a closing console log screen that quickly shows, that was tuned down / darker too.
Comment 13 dougg0k 2025-06-17 23:19:42 UTC
Might be something related to lock screen after all.

You know what fixed the issue, being AFK again, the screen turned black due to inactivity, after coming back on. 

I turned HDR on and it wa fixed.

Not even a reboot did that.

And in the meantime of it, the error again, yet it's working, so probably unrelated.

jun 17 20:16:47 desktop-pc kernel: nvidia-modeset: WARNING: GPU:0: Asustek Computer Inc ROG PG27AQN (DP-2): Failed to initialize G-SYNC
jun 17 20:16:52 desktop-pc kernel: kauditd_printk_skb: 956 callbacks suppressed
jun 17 20:16:54 desktop-pc kscreenlocker_greet[4216]: qt.qpa.wayland: Could not create EGL surface (EGL error 0x3003)
jun 17 20:16:54 desktop-pc kscreenlocker_greet[4216]: Failed to write to the pipe: Bad file descriptor.
jun 17 20:16:58 desktop-pc kernel: kauditd_printk_skb: 1127 callbacks suppressed
jun 17 20:17:03 desktop-pc kernel: kauditd_printk_skb: 3235 callbacks suppressed
jun 17 20:17:10 desktop-pc kernel: kauditd_printk_skb: 1876 callbacks suppressed
jun 17 20:17:40 desktop-pc kernel: kauditd_printk_skb: 210 callbacks suppressed
jun 17 20:18:19 desktop-pc kwin_wayland[3242]: kf.windowsystem: static bool KX11Extras::mapViewport() may only be used on X11
Comment 14 dougg0k 2025-06-19 12:50:38 UTC
Another bug not related to this one, that may have something in common, is a random crash that I reported in another issue before, might have been related to nvidia, where one of the monitors turned it's resolution to 640x480 with a different name.

The something in common is happened after desktop being on lockscreen due to inactivity. 

So there might have some correlation of when problems happen in that part.
Comment 15 Leopard 2025-07-01 20:06:49 UTC
Also happens here, Arch Linux and AMD RDNA 3 gpu combo. After approx 1 hour or so continous usage, screen brightness drops down. Until screen goes to sleep (eg, non activity or triggered manually) waking up screen once agins retains the originally set brightness level.

There are some entires related to HDR in demsg but they are probably not related.
```
   8.541266] [drm] Initialized amdgpu 3.63.0 for 0000:12:00.0 on minor 0
[    8.543767] amdgpu 0000:12:00.0: [drm] Cannot find any crtc or sizes
[    8.828147] amdgpu 0000:03:00.0: vgaarb: VGA decodes changed: olddecodes=io+mem,decodes=none:owns=none
[    8.828150] amdgpu 0000:12:00.0: vgaarb: VGA decodes changed: olddecodes=io+mem,decodes=none:owns=none
[   10.753858] amdgpu 0000:03:00.0: [drm] *ERROR* dc_dmub_srv_log_diagnostic_data: DMCUB error - collecting diagnostic data
[   10.937734] amdgpu 0000:03:00.0: [drm] *ERROR* dc_dmub_srv_log_diagnostic_data: DMCUB error - collecting diagnostic data
[   11.121682] amdgpu 0000:03:00.0: [drm] *ERROR* dc_dmub_srv_log_diagnostic_data: DMCUB error - collecting diagnostic data
[   11.199109] r8169 0000:0e:00.0 enp14s0: Link is Up - 1Gbps/Full - flow control off
[   11.200048] r8169 0000:0e:00.0 enp14s0: Link is Down
[   11.305410] amdgpu 0000:03:00.0: [drm] *ERROR* dc_dmub_srv_log_diagnostic_data: DMCUB error - collecting diagnostic data
[   11.489356] amdgpu 0000:03:00.0: [drm] *ERROR* dc_dmub_srv_log_diagnostic_data: DMCUB error - collecting diagnostic data
[   11.672302] amdgpu 0000:03:00.0: [drm] *ERROR* dc_dmub_srv_log_diagnostic_data: DMCUB error - collecting diagnostic data
[   11.855586] amdgpu 0000:03:00.0: [drm] *ERROR* dc_dmub_srv_log_diagnostic_data: DMCUB error - collecting diagnostic data
[   12.038533] amdgpu 0000:03:00.0: [drm] *ERROR* dc_dmub_srv_log_diagnostic_data: DMCUB error - collecting diagnostic data
[   12.221811] amdgpu 0000:03:00.0: [drm] *ERROR* dc_dmub_srv_log_diagnostic_data: DMCUB error - collecting diagnostic data
[   14.459135] r8169 0000:0e:00.0 enp14s0: Link is Up - 1Gbps/Full - flow control off
[  114.305030] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[  114.305034] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[  114.305202] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[  114.305204] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[  114.305250] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[  114.305251] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[  114.305366] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[  114.305367] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[  114.397284] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[  114.397286] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[  114.397444] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[  114.397445] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[  114.788776] Bluetooth: RFCOMM TTY layer initialized
[  114.788783] Bluetooth: RFCOMM socket layer initialized
[  114.788785] Bluetooth: RFCOMM ver 1.11
[  115.236385] nvme nvme0: using unchecked data buffer
[  658.736486] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1118: core_link_write_dpcd (DP_DOWNSPREAD_CTRL) failed
[  658.755849] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1123: core_link_write_dpcd (DP_LANE_COUNT_SET) failed
[  658.775276] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1151: core_link_write_dpcd (DP_LINK_BW_SET) failed
[  659.302575] snd_hda_codec_hdmi hdaudioC0D0: HDMI: Unknown ELD version 0
[  684.227294] input: [AV] Samsung Soundbar C4-Series (AVRCP) as /devices/virtual/input/input24
[ 1382.403979] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1118: core_link_write_dpcd (DP_DOWNSPREAD_CTRL) failed
[ 1382.423347] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1123: core_link_write_dpcd (DP_LANE_COUNT_SET) failed
[ 1382.442715] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1151: core_link_write_dpcd (DP_LINK_BW_SET) failed
[ 1382.919598] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1118: core_link_write_dpcd (DP_DOWNSPREAD_CTRL) failed
[ 1382.938965] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1123: core_link_write_dpcd (DP_LANE_COUNT_SET) failed
[ 1382.958333] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1151: core_link_write_dpcd (DP_LINK_BW_SET) failed
[ 2118.301805] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[ 2118.301809] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[ 2118.301969] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[ 2118.301971] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[ 2118.302010] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[ 2118.302011] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[ 2118.302121] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[ 2118.302122] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[ 2118.317402] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[ 2118.317404] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[ 2118.317522] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[ 2118.317523] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[ 3290.626905] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[ 3290.626909] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[ 3290.627062] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[ 3290.627064] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[ 3290.627832] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[ 3290.627834] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[ 3290.847458] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1118: core_link_write_dpcd (DP_DOWNSPREAD_CTRL) failed
[ 3290.866886] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1123: core_link_write_dpcd (DP_LANE_COUNT_SET) failed
[ 3290.886250] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1151: core_link_write_dpcd (DP_LINK_BW_SET) failed
[ 3291.368444] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1118: core_link_write_dpcd (DP_DOWNSPREAD_CTRL) failed
[ 3291.387866] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1123: core_link_write_dpcd (DP_LANE_COUNT_SET) failed
[ 3291.407234] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1151: core_link_write_dpcd (DP_LINK_BW_SET) failed
[ 3291.967139] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[ 3291.967141] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[ 3292.392857] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[ 3292.392860] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[ 3677.398173] playstation 0005:054C:09CC.0007: unknown main item tag 0x0
[ 3677.398801] playstation 0005:054C:09CC.0007: hidraw6: BLUETOOTH HID v1.00 Gamepad [Wireless Controller] on 00:1a:7d:da:71:15
[ 3677.586852] input: Wireless Controller as /devices/virtual/misc/uhid/0005:054C:09CC.0007/input/input25
[ 3677.586946] input: Wireless Controller Motion Sensors as /devices/virtual/misc/uhid/0005:054C:09CC.0007/input/input26
[ 3677.587000] input: Wireless Controller Touchpad as /devices/virtual/misc/uhid/0005:054C:09CC.0007/input/input27
[ 3677.587181] playstation 0005:054C:09CC.0007: Registered DualShock4 controller hw_version=0x00003100 fw_version=0x00000051
[ 7699.618154] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[ 7699.618158] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[ 7699.618316] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[ 7699.618318] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[ 7699.619054] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[ 7699.619056] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[ 7699.838898] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1118: core_link_write_dpcd (DP_DOWNSPREAD_CTRL) failed
[ 7699.858265] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1123: core_link_write_dpcd (DP_LANE_COUNT_SET) failed
[ 7699.877627] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1151: core_link_write_dpcd (DP_LINK_BW_SET) failed
[ 7700.356620] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1118: core_link_write_dpcd (DP_DOWNSPREAD_CTRL) failed
[ 7700.375987] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1123: core_link_write_dpcd (DP_LANE_COUNT_SET) failed
[ 7700.395355] amdgpu 0000:03:00.0: [drm] *ERROR* dpcd_set_link_settings:1151: core_link_write_dpcd (DP_LINK_BW_SET) failed
[ 7700.557186] snd_hda_codec_hdmi hdaudioC0D0: HDMI: Unknown ELD version 0
[ 7700.926220] HDR SB:01 1a 02 00 6b 83 d8 3c be 36 08 7f f2 1d bc 0d
[ 7700.926222] HDR SB:3a 3d 47 40 42 01 ed 01 42 01 42 01 00 00 00 00
[ 7836.571825] playstation 0005:054C:09CC.0008: unknown main item tag 0x0
[ 7836.572456] playstation 0005:054C:09CC.0008: hidraw6: BLUETOOTH HID v1.00 Gamepad [Wireless Controller] on 00:1a:7d:da:71:15
[ 7836.642669] input: Wireless Controller as /devices/virtual/misc/uhid/0005:054C:09CC.0008/input/input28
[ 7836.642748] input: Wireless Controller Motion Sensors as /devices/virtual/misc/uhid/0005:054C:09CC.0008/input/input29
[ 7836.642805] input: Wireless Controller Touchpad as /devices/virtual/misc/uhid/0005:054C:09CC.0008/input/input30
[ 7836.642955] playstation 0005:054C:09CC.0008: Registered DualShock4 controller hw_version=0x00003100 fw_version=0x00000051
```
Comment 16 Zamundaaa 2025-07-03 16:36:38 UTC
(In reply to dougg0k from comment #14)
> Another bug not related to this one, that may have something in common, is a
> random crash that I reported in another issue before, might have been
> related to nvidia, where one of the monitors turned it's resolution to
> 640x480 with a different name.
That means the driver failed to read the EDID. Judging by your kscreen-doctor output, it was read properly when the problem happened though.

> You know what fixed the issue, being AFK again, the screen turned black due to inactivity, after coming back on. 
When the issue next happens, could you try intentionally turning the screen off and see if it helps again?

(In reply to Leopard from comment #15)
> Also happens here, Arch Linux and AMD RDNA 3 gpu combo. After approx 1 hour
> or so continous usage, screen brightness drops down. Until screen goes to
> sleep (eg, non activity or triggered manually) waking up screen once agins
> retains the originally set brightness level.
That sounds like it could just be a monitor power saving feature? If you use the buttons on the monitor when it's darker, does that do anything?
Comment 17 dougg0k 2025-07-03 16:46:03 UTC
I just stated that there seem to be a pattern in common when it happened, after inactivity and screen lock.

I didnt see it happening yet in latest 6.4, though it is very random.
Comment 18 Leopard 2025-07-05 13:33:25 UTC
(In reply to Zamundaaa from comment #16)
> (In reply to dougg0k from comment #14)
> > Another bug not related to this one, that may have something in common, is a
> > random crash that I reported in another issue before, might have been
> > related to nvidia, where one of the monitors turned it's resolution to
> > 640x480 with a different name.
> That means the driver failed to read the EDID. Judging by your
> kscreen-doctor output, it was read properly when the problem happened though.
> 
> > You know what fixed the issue, being AFK again, the screen turned black due to inactivity, after coming back on. 
> When the issue next happens, could you try intentionally turning the screen
> off and see if it helps again?
> 
> (In reply to Leopard from comment #15)
> > Also happens here, Arch Linux and AMD RDNA 3 gpu combo. After approx 1 hour
> > or so continous usage, screen brightness drops down. Until screen goes to
> > sleep (eg, non activity or triggered manually) waking up screen once agins
> > retains the originally set brightness level.
> That sounds like it could just be a monitor power saving feature? If you use
> the buttons on the monitor when it's darker, does that do anything?

No, this monitor doesn't have any power saving features. Asus VG32VQR, a pretty old HDR 400 pc monitor. Not a TV. As that dimming doesnt happen when it is in SDR mode.
Comment 19 Bug Janitor Service 2025-07-20 03:47:09 UTC
๐Ÿ›๐Ÿงน โš ๏ธ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

Thank you for helping us make KDE software even better for everyone!
Comment 20 Bug Janitor Service 2025-08-04 03:46:38 UTC
๐Ÿ›๐Ÿงน This bug has been in NEEDSINFO status with no change for at least 30 days. Closing as RESOLVED WORKSFORME.
Comment 21 dougg0k 2025-08-20 13:21:01 UTC
This issue or at least a similar appeared again today.

When HDR are ON, the screen goes off, but if I turn HDR off, it comes back. 

KDE Plasma Version: 6.4.4
KDE Frameworks Version: 6.17.0
Qt Version: 6.9.1
Graphics Platform: Wayland
Comment 22 dougg0k 2025-08-20 13:34:18 UTC
Here is a video of this one https://www.dropbox.com/scl/fi/0gwdkgddcks83yfl0a88x/20250820_102230.mp4_noaudio.mp4?rlkey=s816hd1g0d0n0kyswk9fzlj21&st=4kx7rat7&dl=0

It has been working fine till today. I dont see anything relevant in the logs.
Comment 23 Tyler Bouchard 2025-08-20 20:34:07 UTC
Encountering this same issue, but on Bazzite KDE with an AMD 7900 xt
It appears HDR is being enabled, but the wrong colorspace is being displayed?

Happens under the following scenarios:
-Locked for an extended period of time
-HDR toggled on one monitor causes reproduction on the other.

Results of  kscreen-doctor -o before issue:

kscreen-doctor -o
Output: 1 DP-1 242d7202-03ac-4f2f-8f30-e831aebfbf1e
	enabled
	connected
	priority 1
	DisplayPort
	replication source:0
	Modes:  1:3440x1440@240*!  2:3440x1440@100  3:3440x1440@144  4:3440x1440@120  5:3440x1440@60  6:3440x1440@50  7:1920x1200@240  8:1920x1080@120  9:1920x1080@60  10:1600x1200@240  11:1680x1050@240  12:1280x1024@75  13:1440x900@240  14:1280x800@240  15:1280x720@240  16:1024x768@60  17:800x600@60  18:640x480@60  19:640x480@60  20:1600x1200@60  21:1280x1024@60  22:1280x1024@240  23:1024x768@240  24:1920x1200@60  25:1280x800@60  26:2560x1440@60  27:2560x1440@240  28:1920x1080@240  29:1600x900@60  30:1600x900@240  31:1368x768@60  32:1368x768@240  33:1280x720@60 
	Geometry: 1920,0 3440x1440
	Scale: 1
	Rotation: 1
	Overscan: 0
	Vrr: Automatic
	RgbRange: Automatic
	HDR: enabled
		SDR brightness: 276 nits
		SDR gamut wideness: 0%
		Peak brightness: 564 nits, overridden with: 564 nits
		Max average brightness: 277 nits
		Min brightness: 0.0001 nits
	Wide Color Gamut: enabled
	ICC profile: none
	Color profile source: sRGB
	Color power preference: prefer efficiency and performance
	Brightness control: supported, set to 90% and dimming to 100%
	DDC/CI: allowed
	Color resolution: automatic (10), range: [8; 16] bits per color
	Allow EDR: unsupported
Output: 2 DP-2 e39dc5cf-0ddb-42e6-9384-c649dc54e71a
	enabled
	connected
	priority 2
	DisplayPort
	replication source:0
	Modes:  34:1920x1080@240*!  35:1920x1080@144  36:1920x1080@120  37:1920x1080@60  38:1920x1080@60  39:1920x1080@60  40:1920x1080@50  41:1680x1050@240  42:1280x1024@240  43:1280x1024@120  44:1280x1024@75  45:1280x1024@60  46:1440x900@240  47:1280x960@240  48:1280x800@240  49:1280x720@60  50:1280x720@60  51:1280x720@50  52:1024x768@240  53:1024x768@120  54:1024x768@75  55:1024x768@60  56:800x600@120  57:800x600@75  58:800x600@60  59:720x480@60  60:720x480@60  61:640x480@120  62:640x480@75  63:640x480@60  64:640x480@60  65:640x480@60  66:1280x800@60  67:1600x900@60  68:1600x900@240  69:1368x768@60  70:1368x768@240  71:1280x720@240 
	Geometry: 0,160 1920x1080
	Scale: 1
	Rotation: 1
	Overscan: 0
	Vrr: Automatic
	RgbRange: Automatic
	HDR: enabled
		SDR brightness: 300 nits
		SDR gamut wideness: 0%
		Peak brightness: 400 nits, overridden with: 400 nits
		Max average brightness: 344 nits
		Min brightness: 0.0984 nits
	Wide Color Gamut: enabled
	ICC profile: none
	Color profile source: sRGB
	Color power preference: prefer efficiency and performance
	Brightness control: supported, set to 100% and dimming to 100%
	DDC/CI: allowed
	Color resolution: automatic (10), range: [8; 16] bits per color
	Allow EDR: unsupported

Results after issue invoked on display DP-2:
kscreen-doctor -o
Output: 1 DP-1 242d7202-03ac-4f2f-8f30-e831aebfbf1e
	enabled
	connected
	priority 1
	DisplayPort
	replication source:0
	Modes:  1:3440x1440@240*!  2:3440x1440@100  3:3440x1440@144  4:3440x1440@120  5:3440x1440@60  6:3440x1440@50  7:1920x1200@240  8:1920x1080@120  9:1920x1080@60  10:1600x1200@240  11:1680x1050@240  12:1280x1024@75  13:1440x900@240  14:1280x800@240  15:1280x720@240  16:1024x768@60  17:800x600@60  18:640x480@60  19:640x480@60  20:1600x1200@60  21:1280x1024@60  22:1280x1024@240  23:1024x768@240  24:1920x1200@60  25:1280x800@60  26:2560x1440@60  27:2560x1440@240  28:1920x1080@240  29:1600x900@60  30:1600x900@240  31:1368x768@60  32:1368x768@240  33:1280x720@60 
	Geometry: 1920,0 3440x1440
	Scale: 1
	Rotation: 1
	Overscan: 0
	Vrr: Automatic
	RgbRange: Automatic
	HDR: disabled
	Wide Color Gamut: disabled
	ICC profile: none
	Color profile source: sRGB
	Color power preference: prefer efficiency and performance
	Brightness control: supported, set to 90% and dimming to 100%
	DDC/CI: allowed
	Color resolution: automatic (10), range: [8; 16] bits per color
	Allow EDR: unsupported
Output: 2 DP-2 e39dc5cf-0ddb-42e6-9384-c649dc54e71a
	enabled
	connected
	priority 2
	DisplayPort
	replication source:0
	Modes:  34:1920x1080@240*!  35:1920x1080@144  36:1920x1080@120  37:1920x1080@60  38:1920x1080@60  39:1920x1080@60  40:1920x1080@50  41:1680x1050@240  42:1280x1024@240  43:1280x1024@120  44:1280x1024@75  45:1280x1024@60  46:1440x900@240  47:1280x960@240  48:1280x800@240  49:1280x720@60  50:1280x720@60  51:1280x720@50  52:1024x768@240  53:1024x768@120  54:1024x768@75  55:1024x768@60  56:800x600@120  57:800x600@75  58:800x600@60  59:720x480@60  60:720x480@60  61:640x480@120  62:640x480@75  63:640x480@60  64:640x480@60  65:640x480@60  66:1280x800@60  67:1600x900@60  68:1600x900@240  69:1368x768@60  70:1368x768@240  71:1280x720@240 
	Geometry: 0,160 1920x1080
	Scale: 1
	Rotation: 1
	Overscan: 0
	Vrr: Automatic
	RgbRange: Automatic
	HDR: enabled
		SDR brightness: 300 nits
		SDR gamut wideness: 0%
		Peak brightness: 400 nits, overridden with: 400 nits
		Max average brightness: 344 nits
		Min brightness: 0.0984 nits
	Wide Color Gamut: enabled
	ICC profile: none
	Color profile source: sRGB
	Color power preference: prefer efficiency and performance
	Brightness control: supported, set to 100% and dimming to 100%
	DDC/CI: allowed
	Color resolution: automatic (10), range: [8; 16] bits per color
	Allow EDR: unsupported

No visible change on that front.
I can very reliably reproduce this issue (I can make it occur on demand), so let me know if you want any other logs and how to retrieve them.
Comment 24 Tyler Bouchard 2025-08-20 20:51:24 UTC
Here's video of the issue.
The best I can tell is going on, sans logs just with guesstimates, is when one monitor's HDR status is changed, it's applying to the other as well but without changing anything else required. (So color space changes but not the brightness, etc)

So if you went and changed the HDR setting on monitor 1 it applies to both without actually signaling it to the second monitor and vice versa. So the brightness issue actually seems to perhaps be that disabling HDR on one monitor disables it on both but leaves the monitor its being applied to as the only one fully adjusting. If both monitors then turn off for an extended sleep when locked there may be a race condition whereby the monitors turning on leave it so whichever one turns on first is "safe" while the other suffers from the issue.

Because it's always the monitor successfully being change that doesn't encounter the issue. It's always the other monitor.

https://www.dropbox.com/scl/fi/4pifpzj2ekmg7y4lr296z/VID_20250820_164215468.mp4?rlkey=x0wopsvtrqpqyc7hlegpp5pyk&st=5c7d7e2d&dl=0
Comment 25 dougg0k 2025-08-20 21:05:27 UTC
That is not the case in the setup here, the HDR on the second monitor are really bad, but it doesnt affect anything on that.
Comment 26 Tyler Bouchard 2025-08-20 21:08:39 UTC
(In reply to dougg0k from comment #25)
> That is not the case in the setup here, the HDR on the second monitor are
> really bad, but it doesnt affect anything on that.

I can still provide whatever logs are necessary. Just need to be told where to check. Since I can still cause the brightness issue on command.
Comment 27 Bernd Steinhauser 2025-09-08 06:31:30 UTC
I think I get this too, although maybe it's just very similar. For me it triggers when the screen is switched off and on again (which effectively means reconnect). Then brightness and colors are completely off.

It's fixed for me by re-applying the screen settings in Display & Monitor, at least until I turn off the screen next time.
Comment 28 Zamundaaa 2025-09-08 12:33:17 UTC
The issues on AMD are a different problem, and a bug in the driver. See https://gitlab.freedesktop.org/drm/amd/-/issues/4444 for more details.
Comment 29 Bernd Steinhauser 2025-09-08 17:18:43 UTC
(In reply to Zamundaaa from comment #28)
> The issues on AMD are a different problem, and a bug in the driver. See
> https://gitlab.freedesktop.org/drm/amd/-/issues/4444 for more details.

Thanks.
Comment 30 Zamundaaa 2025-10-14 15:17:08 UTC
Does this still happen to you in Plasma 6.4?
If yes, does setting color accuracy of the screen to "prefer color accuracy" make a difference?
Comment 31 dougg0k 2025-10-14 15:59:28 UTC
I didnt see this happening anymore.

KDE Plasma Version: 6.4.5
KDE Frameworks Version: 6.19.0

However another one happened recently, but only one time. https://bugs.kde.org/show_bug.cgi?id=510145
Comment 32 Zamundaaa 2025-10-16 20:44:44 UTC
Cool
Comment 33 dougg0k 2025-10-21 20:06:02 UTC
Just after commenting out the other day, the issue happened today.

But this time, it was even before logging back out, just by appearing or the monitor turning back on from being afk.

out 21 16:56:14 desktop-pc dbus-broker[815]: A security policy denied :1.46 to send method call /org/freedesktop/login1/seat/seat0:org.freedesktop.login1.Seat.Inhibit to org.freedesktop.login1.
out 21 16:56:14 desktop-pc kwin_wayland[2354]: Failed to delay sleep: Sender is not authorized to send message
out 21 16:56:14 desktop-pc dbus-broker[815]: A security policy denied :1.46 to send method call /org/freedesktop/login1/seat/seat0:org.freedesktop.login1.Seat.Inhibit to org.freedesktop.login1.
out 21 16:56:14 desktop-pc kwin_wayland[2354]: Failed to delay sleep: Sender is not authorized to send message
out 21 16:59:22 desktop-pc kernel: nvidia-modeset: WARNING: GPU:0: Asustek Computer Inc ROG PG27AQN (DP-2): Failed to initialize G-SYNC
out 21 16:59:35 desktop-pc kscreenlocker_greet[49808]: Could not create EGL surface (EGL error 0x3003)
out 21 16:59:35 desktop-pc kscreenlocker_greet[49808]: Could not create EGL surface (EGL error 0x3003)
out 21 16:59:35 desktop-pc kscreenlocker_greet[49808]: Failed to write to the pipe: Transport endpoint is not connected.

KDE Plasma Version: 6.4.5
KDE Frameworks Version: 6.19.0
Qt Version: 6.10.0
Comment 34 dougg0k 2025-10-21 20:14:10 UTC
Not even a reboot or shutdown fixed the issue, it's as if suddenly HDR didnt work again
Comment 35 dougg0k 2025-10-21 20:16:35 UTC
I also tested with both options from color accuracy, same result. 

I try enabling HDR in another monitor, works fine there.
Comment 36 Zamundaaa 2025-10-21 20:59:58 UTC
Okay, so you now always have the buggy state? Then let's use this to try a few things:
- first, attach ~/.config/kwinoutputconfig.json and the output of "kscreen-doctor -o" here
- setting color accuracy you already tried
- try changing the brightness setting in HDR mode
- try disabling HDR, changing brightness to 100% in SDR mode, and then turn back to HDR

Also, does your PC have an internal GPU that you could test the screen's HDR mode with? Better yet, a different PC?
Comment 37 dougg0k 2025-10-21 21:16:04 UTC
https://pastebin.com/raw/RJbwi79P

Output: 1 DP-1 aaed40a9-0cb0-43b8-a8dd-ba3892ec137b
        enabled
        connected
        priority 2
        DisplayPort
        replication source:0
        Modes:  1:2560x1440@60!  2:2560x1440@360*  3:2560x1440@240  4:2560x1440@144  5:2560x1440@120  6:2560x1440@100  7:2368x1332@360  8:2368x1332@240  9:1920x1080@360  10:1920x1080@240  11:1920x1080@120  12:1024x768@60  13:800x600@60  14:640x480@60
        Geometry: 0,2160 2560x1440
        Scale: 1
        Rotation: 1
        Overscan: 0
        Vrr: Never
        RgbRange: unknown
        HDR: enabled
                SDR brightness: 230 nits
                SDR gamut wideness: 10%
                Peak brightness: 630 nits, overridden with: 630 nits
                Max average brightness: 400 nits
                Min brightness: 0.0994 nits
        Wide Color Gamut: enabled
        ICC profile: /home/user/.dotfiles/configs/pg27aqn_color_profile.icm
        Color profile source: ICC
        Color power preference: prefer accuracy
        Brightness control: supported, set to 90% and dimming to 100%
        DDC/CI: allowed
        Color resolution: unknown
        Allow EDR: unsupported

- I tried changing brightness, I see the effect, if the brightness are reduced, it made the screen even darker.
- Didnt do anything changing to 100% in SDR and changing back to HDR.
- No, only a external GPU - RTX3080Ti - Dont have another PC.
Comment 38 dougg0k 2025-10-21 21:28:09 UTC
I found something that fixes the issue in the monitor.

Variable Backlight in the monitor, change to off and back to one of the levels.
Comment 39 dougg0k 2025-10-21 21:28:56 UTC
Ok, fixes but not really, after doing so, I tried disabling and enabling again, it went back to the darker mode.
Comment 40 Zamundaaa 2025-10-21 21:32:24 UTC
Okay. FWIW I looked around a bit and it seems like the monitor is probably just defective, you're not the first this happened to: https://www.reddit.com/r/Monitors/comments/10hphh3/asus_pg27aqn_dim_screen_help/
People there mention that it was resolved when plugging into a different outlet / power cycling the power brick, but you may be best off getting support or a replacement from the store you bought it from.
Comment 41 dougg0k 2025-10-21 22:00:03 UTC
Not so sure, It only ever happened in KDE. 

I've seen and reported plenty issues with KDE coming out of login.

And, if you see in the thread, I was not the only one that reported the issue.

https://discuss.kde.org/t/very-dark-picture-when-streaming-hdr-using-sunshine/23407
https://github.com/LizardByte/Sunshine/issues/3298
Comment 42 Zamundaaa 2025-10-21 22:51:48 UTC
Sunshine is known to be broken because it uses kmsgrab which is a giant hack and cannot ever reliably work. It is also not at all related to what's visible on the actual display.

I'm sorry that your display has issues, but there's nothing we can do about it.
Comment 43 dougg0k 2025-10-21 22:57:17 UTC
Ok.

So, could you tell why all or almost all issues that has happened with KDE related to display in some way, has been after log-in after being afk?

Why not in another way?