Setting CRTC error

[limbouser]

I am trying to build flutter-pi on a platform other than Raspbian. I got stuck at the following point.

Swapping buffers... Locking front buffer... getting new framebuffer for BO... Setting CRTC... failed to set mode: Permission denied

Why would this come up? Do you have any idea?

[ardera]

Two possibilities that come to my mind:

• either you have insufficient permissions to access the device files in /dev/dri/. Try running flutter-pi as root or adding your user to the necessary groups. (2nd one is system-dependant, can't give you instructions for that)
• some other application is the DRM master and opened the device files under /dev/dri/ before flutter-pi did. That could be an x-server, wayland, or some other application using graphics.

[ardera]

Any news on this? If not I'll close this issue.

[limbouser]

Yh. I'm closing it. This came up whenever I used an image with an UI even though minimal. Whatever, thanks for the help.

[limbouser]

drm_mode_config_cleanup this is something that cameup when I was navigating on some help with this issue. Is their anyway this can be useful to you such that flutter-pi if run on a platform with an application using graphics can free it up and start the flutter application?

[ardera]

Thanks for the input. I'm afraid drm_mode_config_cleanup is not a solution though. That function is defined inside the linux kernel to be used by drivers. It's not available to userspace.

This came up whenever I used an image with an UI even though minimal. Whatever, thanks for the help.

I just now understood what you meant by this 😄 Using any linux OS with an enabled graphical user interface will probably not work, because of the 2nd thing I mentioned in my previous comment. You need to disable the UI and make sure no X11- or wayland-server is starting up. There are many guides on that online. (Just google <your distro> boot to console or something like that)

This may work, but I'm not sure:

sudo systemctl set-default multi-user.target --force

If you need graphical UI, you can't use flutter-pi. Consider using the official linux desktop embedding for flutter.