Bug 321001

Summary: Add support for xrandr 1.4 provider objects (PRIME, Displaylink, ...)
Product: [Plasma] KScreen Reporter: Stefan Brüns <stefan.bruens>
Component: commonAssignee: Sebastian Kügler <sebas>
Status: RESOLVED UNMAINTAINED    
Severity: wishlist CC: cfeck, jgrulich, kde, nate, xaver.hugl
Priority: NOR    
Version: unspecified   
Target Milestone: ---   
Platform: Other   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:
Bug Depends on:    
Bug Blocks: 343900    

Description Stefan Brüns 2013-06-10 15:01:39 UTC
xrandr 1.4 added provider objects. These are useful for e.g. NVidia Optimus/PRIME support, additional outputs via Displaylink USB devices, ...
Comment 1 Christoph Feck 2015-01-23 00:09:33 UTC
Thank you for your bug report or feature request.

Unfortunately, we did not have a maintainer for the "krandr" components, which are used to manage displays and monitors in the KDE Workspaces.

The "krandr" components has been superseded by "KScreen" in newer releases of the KDE Workspaces. It is compatible with all versions since 4.11, and is also used with Plasma 5. Please check with your distribution how to update to KScreen.

If this issue or feature request is still applicable to KScreen version 1.0.5 or newer, please add a comment. We will then reassign this ticket to KScreen developers.

If you are already using KScreen to manage displays or monitors, and found a different bug or need a specific feature, please create a new ticket for "KScreen" product in this bugzilla using this link: https://bugs.kde.org/enter_bug.cgi?product=KScreen

(This is an automatic message from the KDE Bug Triaging Team)
Comment 2 Stefan Brüns 2015-01-23 19:56:17 UTC
Please reassign to kscreen
Comment 3 Christoph Feck 2015-01-23 20:26:41 UTC
Okey :)
Comment 4 Daniel Vrátil 2015-02-05 11:07:34 UTC
*** Bug 324076 has been marked as a duplicate of this bug. ***
Comment 5 Sebastian Kügler 2017-02-06 16:04:39 UTC
Could you explain what the problem is specifically? I.e. which devices you'd like to use, what setup exactly?

"Add support for $abstract_feature" doesn't give me a lot of useful information to prioritize this feature request.

Thanks!
Comment 6 Stefan Brüns 2017-02-06 17:07:54 UTC
(In reply to Sebastian Kügler from comment #5)
> Could you explain what the problem is specifically? I.e. which devices you'd
> like to use, what setup exactly?
> 
> "Add support for $abstract_feature" doesn't give me a lot of useful
> information to prioritize this feature request.
> 
> Thanks!

I don't have any device with NVidia switchable graphics, so I can only give specific information about the DisplayLink USB adapters:

The DL is more or less a dumb framebuffer, connected via USB. The kernel adds it as a graphics device, and X shows it as a "Sink Output" provider (xrandr --listproviders). With "xrandr --setprovideroutputsource intel udlfb" (identifiers are made up, sorry), it is possible to add the DL as an additional output, i.e. the graphics are rendered on the Intel GPU and "copied" to the USB framebuffer.

There are two parts which should be possible:
1. Connecting the "Output Sink" to the source
2. Configuring the resolution etc. of the sink
Comment 7 Sebastian Kügler 2017-02-06 17:33:56 UTC
Thanks for the information, that makes sense.

Unfortunately, I don't have these switchable graphics either, so we'd need someone who has, and can work on this.
Comment 8 Kai Uwe Broulik 2017-02-06 17:52:50 UTC
Jan did a bunch of hybrid-graphics related stuff lately.
Comment 9 Jan Grulich 2017-02-07 06:20:12 UTC
I would like to help, but I don't want to dive into KScreen right now. I can however provide information (like outputs etc.) and of course help with testing.

Output from xrander --listproviders:
Providers: number : 2
Provider 0: id: 0x90 cap: 0xb, Source Output, Sink Output, Sink Offload crtcs: 4 outputs: 10 associated providers: 1 name:Intel
Provider 1: id: 0x65 cap: 0x7, Source Output, Sink Output, Source Offload crtcs: 4 outputs: 2 associated providers: 1 name:nouveau
Comment 10 Sebastian Kügler 2017-02-07 12:01:28 UTC
Being realistic, I won't have time to work on this specific topic in the foreseeable future, so someone else would have to pick it up. I can help with reviewing patches (so far as I understand the X11 bits involved), however.

Task is up for adoption.
Comment 11 Zamundaaa 2025-01-10 17:01:06 UTC
The X11 session is in maintenance mode; this won't be implemented anymore.