Bug 504889 - Power Profile incorrectly shown when hardware does not support it
Summary: Power Profile incorrectly shown when hardware does not support it
Status: RESOLVED FIXED
Alias: None
Product: plasmashell
Classification: Plasma
Component: Power and Battery widget (other bugs)
Version First Reported In: 6.3.5
Platform: Solus Linux
: NOR normal
Target Milestone: 1.0
Assignee: Plasma Bugs List
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2025-05-27 21:09 UTC by TraceyC
Modified: 2025-05-28 13:43 UTC (History)
3 users (show)

See Also:
Latest Commit:
Version Fixed In: 6.3.6
Sentry Crash Report:


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Description TraceyC 2025-05-27 21:09:51 UTC
SUMMARY
"Power Profile" is shown in Power and Battery  *but* the system does not support power profiles. The message says to install power-profiles-daemon installed even whe power-profiles-daemon is installed

This is confusing. It makes it look like there's a bug in the applet detecting the package being installed. This provides no valuable information to the user when their system doesn't support using power-profiles-daemon.

Note: This was reported to Solus by a user on Plasma 6.3.5, I reproduced on git-master

SYSTEM SETUP
A system with a CPU that does not support pstates e.g. any AMD earlier than Zen2
power-profiles-daemon is installed, powerprofilesctl is running

Cheat sheet for AMD CPUs
https://www.pcgamer.com/heres-your-cheat-sheet-for-amds-zen-based-cpu-nomenclature/

Check with the following. If it says `amd-pstate`, pstate is supported, otherwise it is not

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_driver


STEPS TO REPRODUCE
1. Have / add a default panel with the system tray 
2. Click on the Power and Brightness app

OBSERVED RESULT
"Power profiles" is shown with the message  
"Power profiles may be supported on your device. Try installing the power-profiles-daemon package using your distribution's package manager and restarting the system"

EXPECTED RESULT
"Power profiles" is not shown

SOFTWARE/OS VERSIONS
Operating System: Solus 4.7
KDE Plasma Version: 6.3.5
KDE Frameworks Version: 6.14.0
Qt Version: 6.8.3
Kernel Version: 6.14.6-319.current (64-bit)
Graphics Platform: Wayland
Processors: 8 × AMD Ryzen 7 3700U with Radeon Vega Mobile Gfx
Memory: 17.5 GiB of RAM
Graphics Processor: AMD Radeon Vega 10 Graphics
Manufacturer: LENOVO
Product Name: 81SS
System Version: Lenovo IdeaPad FLEX-14API

$ powerprofilesctl
    balanced:
    PlatformDriver: placeholder

    power-saver:
    PlatformDriver: placeholder


ADDITIONAL INFORMATION
For systems where the CPU is not supported by power-profiles-daemon, telling the user to install it is counter-productive. power-profiles-daemon conflicts with other governers like scheduti, which supports some CPUs the former doesn't.

The user report on the Solus forums:
https://discuss.getsol.us/d/11649-power-widget-cant-change-profiles-decrease-temperature-amd-zen-cpu-on-kde

The affected system has Plasma 6.3.5 and a AMD Zen+ Ryzen 5 2500U

On that system they have the same output from powerprofilesctl
    huawei@huawei-solus ~ $ powerprofilesctl
    balanced:
    PlatformDriver: placeholder

    power-saver:
    PlatformDriver: placeholder
    huawei@huawei-solus ~ $

SUGGESTION
If powerprofilesctl can be queried, and shows "PlatformDriver: placeholder", do not show the Power Profile entry.

I don't know if there's a more robust way of determining if a particular system CPU is supported by power-profiles-daemon to prevent the suggestion to install it if it's not going to be supported
Comment 1 TraceyC 2025-05-27 21:10:13 UTC
Confirming, since I can reproduce
Comment 2 Nate Graham 2025-05-27 21:16:27 UTC
A bit complicated. We basically treat this situation as a distro bug; the PPD package *should* be pre-installed, and is even called out as such in https://community.kde.org/Distributions/Packaging_Recommendations#3rd-party_packages. The message in the applet is designed to subtly alert the user that their distro forgot something, and that they can fix it themselves. We have similar messages throughout Plasma, most notably in Discover, because Plasma is complex and it's easy for distros to forget things.

The only time this message does not make sense IMO is on distros that are tied to hardware that it's known to not support PPD. An example is SteamOS. In that case, it probbly makes sense to patch out the message.

Other than that case, I fail to see how this isn't a distro bug.

> For systems where the CPU is not supported by power-profiles-daemon, telling the user to install
> it is counter-productive. power-profiles-daemon conflicts with other governers like schedutil,
> which supports some CPUs the former doesn't.

We don't formally support that though. PPD is the thing we support.

What do you think we should do here?
Comment 3 TraceyC 2025-05-28 00:23:25 UTC
If the applet is telling the user to install power-profiles-daemon, but it *is* installed, but won't work for the CPU, how would a distro fix that? This seems like a bug in the applet.
Comment 4 Nate Graham 2025-05-28 02:49:02 UTC
Oh wait, PPD is installed but the widget thinks it isn't? Hmm, yes that would be a bug.
Comment 5 Bug Janitor Service 2025-05-28 02:55:16 UTC
A possibly relevant merge request was started @ https://invent.kde.org/plasma/powerdevil/-/merge_requests/554
Comment 6 Nate Graham 2025-05-28 13:42:02 UTC
Git commit 8aca3d2bf22117924ff10dc7f897ca3966830786 by Nate Graham.
Committed on 28/05/2025 at 02:53.
Pushed by ngraham into branch 'master'.

applets/batterymonitor: don't ask to install PPD when already installed

A logic error in this code resulted in the "try installing PPD" message
appearing for people with PPD installed but using using hardware that
doesn't support PPD yet.
FIXED-IN: 6.3.6

M  +1    -1    applets/batterymonitor/package/contents/ui/PowerProfileItem.qml

https://invent.kde.org/plasma/powerdevil/-/commit/8aca3d2bf22117924ff10dc7f897ca3966830786
Comment 7 Nate Graham 2025-05-28 13:42:26 UTC
Git commit 60f7e31049fdc8b6b36771ac3d177c9b93abf471 by Nate Graham.
Committed on 28/05/2025 at 13:42.
Pushed by ngraham into branch 'Plasma/6.4'.

applets/batterymonitor: don't ask to install PPD when already installed

A logic error in this code resulted in the "try installing PPD" message
appearing for people with PPD installed but using using hardware that
doesn't support PPD yet.
FIXED-IN: 6.3.6


(cherry picked from commit 8aca3d2bf22117924ff10dc7f897ca3966830786)

Co-authored-by: Nate Graham <nate@kde.org>

M  +1    -1    applets/batterymonitor/package/contents/ui/PowerProfileItem.qml

https://invent.kde.org/plasma/powerdevil/-/commit/60f7e31049fdc8b6b36771ac3d177c9b93abf471
Comment 8 Nate Graham 2025-05-28 13:43:39 UTC
Git commit eb1f73c3e6146d5bb3d6237754f7c28d9a43e57f by Nate Graham.
Committed on 28/05/2025 at 13:43.
Pushed by ngraham into branch 'Plasma/6.3'.

applets/batterymonitor: don't ask to install PPD when already installed

A logic error in this code resulted in the "try installing PPD" message
appearing for people with PPD installed but using using hardware that
doesn't support PPD yet.
FIXED-IN: 6.3.6


(cherry picked from commit 8aca3d2bf22117924ff10dc7f897ca3966830786)

Co-authored-by: Nate Graham <nate@kde.org>

M  +1    -1    applets/batterymonitor/package/contents/ui/PowerProfileItem.qml

https://invent.kde.org/plasma/powerdevil/-/commit/eb1f73c3e6146d5bb3d6237754f7c28d9a43e57f