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sidevesh / Luminance

A simple GTK application to control brightness of displays including external displays supporting DDC/CI
GNU General Public License v3.0
91 stars 4 forks source link

[Fedora] Open failed for /dev/i2c-0: errno=EACCES(13): Permission denied #12

Closed mitchhentges closed 1 year ago

mitchhentges commented 1 year ago

This lil app is very cool, thanks for making it!

I installed luminance-1.0.1.rpm on my Fedora 38 machine, but after running it, it says "No compatible displays found". Running it in the terminal with com.sidevesh.Luminance, I see:

$ com.sidevesh.Luminance 
Open failed for /dev/i2c-0: errno=EACCES(13): Permission denied
Open failed for /dev/i2c-1: errno=EACCES(13): Permission denied
Open failed for /dev/i2c-2: errno=EACCES(13): Permission denied
Open failed for /dev/i2c-3: errno=EACCES(13): Permission denied
Open failed for /dev/i2c-4: errno=EACCES(13): Permission denied
Open failed for /dev/i2c-5: errno=EACCES(13): Permission denied
Open failed for /dev/i2c-6: errno=EACCES(13): Permission denied

Workaround

Run the app as root :sweat_smile: : sudo com.sidevesh.Luminance

sidevesh commented 1 year ago

Can you try running ddcutil environment ? This installs ddcutil as a dependency and that is supposed to install a udev rule to get the current user permission to work with those files. Did you restart after installing the app ? You probably need to restart so that the udev rules take effect. I don't use a rpm based distro so things would be different, thanks for helping debug this.

mitchhentges commented 1 year ago

Did you restart after installing the app ? You probably need to restart so that the udev rules take effect.

This was the missing piece, thanks!