Debian Testing : No displays found

[pled]

Hi, I Just discovered and installed your application using .deb on my Debian Trixie. I have 2 displays supposed to support DDC/CI :

• AOC 24G2SPU
• Philips 243S7

When launching Luminance GUI, I get "No displays found". When using command line, here is what I get :

$ /usr/bin/com.sidevesh.Luminance -l
No displays found.

(libddcutil:5852): GLib-CRITICAL **: 10:06:27.249: g_atomic_ref_count_dec: assertion 'old_value > 0' failed
Erreur de segmentation

NOTE : After that, I cannot launch it again, it says "Another instance of the application is already running." although I don't see anything in the process list.

System uses Wayland and here is the config :

$ neofetch 
       _,met$$$$$gg.          pascal@Ryzen7-5700G 
    ,g$$$$$$$$$$$$$$$P.       ------------------- 
  ,g$$P"     """Y$$.".        OS: Debian GNU/Linux trixie/sid x86_64 
 ,$$P'              `$$$.     Kernel: 6.9.7-amd64 
',$$P       ,ggs.     `$$b:   Uptime: 4 mins 
`d$$'     ,$P"'   .    $$$    Packages: 3280 (dpkg), 6 (flatpak) 
 $$P      d$'     ,    $$P    Shell: bash 5.2.21 
 $$:      $$.   -    ,d$$'    Resolution: 1920x1080 
 $$;      Y$b._   _,d$P'      DE: GNOME 44.9 
 Y$$.    `.`"Y$$$$P"'         WM: Mutter 
 `$$b      "-.__              WM Theme: Adwaita 
  `Y$$                        Theme: Adwaita [GTK2/3] 
   `Y$$.                      Icons: Colloid [GTK2/3] 
     `$$b.                    Terminal: kgx 
       `Y$$b.                 CPU: AMD Ryzen 7 5700G with Radeon Graphics (16) @ 4.67 
          `"Y$b._             GPU: AMD ATI Radeon Vega Series / Radeon Vega Mobile Se 
              `"""            Memory: 4531MiB / 31389MiB 

Let me know if you need more information, or if I missed something.

[sidevesh]

if you delete the /tmp/com.sidevesh.Luminance.lock file then the app will run again, can you try using ddcutil interrogate command and let me know if it is able to list and control your monitors ?

[pled]

Here is the output :

$ ddcutil interrogate
No /dev/i2c devices exist.
ddcutil requires module i2c-dev.

So I created that file (if module i2c-dev is not built into your kernel) :

$ cat /etc/modules-load.d/ddcutil.conf 
i2c-dev

After reboot, I can see my monitors in Luminance ! :+1:

NOTE : the brand for Display 2 (AOC) is not displayed. Looking at ddcutil ouput, it is like this :

$ ddcutil detect
Display 1
   I2C bus:  /dev/i2c-3
   DRM connector:           card0-HDMI-A-1
   EDID synopsis:
      Mfg id:               PHL - Philips Consumer Electronics Company
      Model:                PHL 243S7
      Product code:         2319  (0x090f)
      Serial number:        UHB1847036174
      Binary serial number: 36174 (0x00008d4e)
      Manufacture year:     2018,  Week: 47
   VCP version:         2.2

Display 2
   I2C bus:  /dev/i2c-6
   DRM connector:           card0-DP-1
   EDID synopsis:
      Mfg id:               AOC - UNK
      Model:                24G2W1G3-
      Product code:         9218  (0x2402)
      Serial number:        1J4PBHA008631
      Binary serial number: 8631 (0x000021b7)
      Manufacture year:     2023,  Week: 47
   VCP version:         2.1

The manufacturer is in Mfg id, the 3 first characters... May be you could enhance the display in the App ?

[sidevesh]

Enhancing the name of monitor is something ddcutil will have to do since this app relies on it, I am glad the issue is resolved for you, Closing ticket

[pled]

Strictly speaking, ddcutil returns the model for model field, that sounds logical. The brand is in the Mfg id field.

So in other words, you may also displays the brand along the model name for each monitor, to enhance your app. Just a suggestion.