Two displays one screen

Help
1

I have HP Envy 34 All-in-One https://www.hp.com/us-en/shop/mdp/desktops/hp-envy-34-all-in-one
It uses two displays in single monitor device. Plasma can’t use it as single device but Windows (and Gnome!) can.

Arch, latest plasma release (6.3.2), wayland.

PXL_20250303_155112196
PXL_20250303_1551121961920×1080 151 KB

PXL_20250303_155125709
PXL_20250303_1551257091920×1080 85.5 KB

PXL_20250303_155129737
PXL_20250303_1551297371920×1080 89.3 KB

PXL_20250303_155139264
PXL_20250303_1551392641920×1080 120 KB

2

What do kscreen-doctor -o and drm_info -j command output ?

sudo get-edid | parse-edid would be interesting too.

3 
[umnik@bigPC ~]$ kscreen-doctor -o
Output: 1 DP-1
        enabled
        connected
        priority 1
        DisplayPort
        Modes:  1:2560x2160@60*! 
        Geometry: 0,0 2560x2160
        Scale: 1
        Rotation: 1
        Overscan: 0
        Vrr: incapable
        RgbRange: Automatic
        HDR: incapable
        Wide Color Gamut: incapable
        ICC profile: none
        Color profile source: EDID
        Color power preference: prefer accuracy
        Brightness control: supported, set to 100% and dimming to 100%
Output: 2 DP-2
        enabled
        connected
        priority 2
        DisplayPort
        Modes:  2:2560x2160@60*  3:2560x2160@60! 
        Geometry: 2560,0 2560x2160
        Scale: 1
        Rotation: 1
        Overscan: 0
        Vrr: incapable
        RgbRange: Automatic
        HDR: incapable
        Wide Color Gamut: incapable
        ICC profile: none
        Color profile source: EDID
        Color power preference: prefer efficiency and performance
        Brightness control: supported, set to 100% and dimming to 100%

This is read-edid version 3.0.2. Prepare for some fun.
Attempting to use i2c interface
No EDID on bus 0
No EDID on bus 1
No EDID on bus 2
No EDID on bus 3
No EDID on bus 4
No EDID on bus 5
No EDID on bus 6
No EDID on bus 7
No EDID on bus 8
No EDID on bus 9
No EDID on bus 12
No EDID on bus 13
No EDID on bus 14
No EDID on bus 15
2 potential busses found: 10 11
Will scan through until the first EDID is found.
Pass a bus number as an option to this program to go only for that one.
256-byte EDID successfully retrieved from i2c bus 10
Looks like i2c was successful. Have a good day.
Checksum Correct

Section "Monitor"
        Identifier "HP ALL-in-One\"
        ModelName "HP ALL-in-One\"
        VendorName "HPN"
        # Monitor Manufactured week 0 of 2021
        # EDID version 1.4
        # Digital Display
        DisplaySize 800 340
        Gamma 2.20
        Option "DPMS" "false"

        #Extension block found. Parsing...
I only know about extension blocks of type 02h. PLEASE email me!
Something strange happened. Please contact the author,
Matthew Kern at <pyrophobicman@gmail.com>
4

File is too big for sending as reply: cloud.myachin.xyz/s/eR4Hs9SwL6yWQ2C

5

Displays like that are unfortunately not properly supported yet, see 427545 – Dual DisplayPort monitors (tiled, MST, e.g. 5k) are not supported by KWin

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