We need to support a mirrored output of a Qt application to LVDS and HDMI displays. The hardware platform is IMX6Q-based board. No Window Managers (X11 or Wayland), just plain Qt5 application. BSP version is 3.14.52.
By the kernel configuration. we already have /dev/fb0 for LVDS and /dev/fb2 for HDMI, and are able to output the graphics output to either LVDS or HDMI. Now we need to implement mirroring of LVDS to HDMI.
I've seen some suggestions (like to use a patch https://community.nxp.com/message/959332?commentID=959332#comment-959332?q=imx6q%20cloned%20displays ), but they are pretty old and I'm wondering if there is a solution already present in the current 4.14.78-based BSP?
Is such mirroring ever possible to implement on the IMX6Q hardware level, or should we look to implement mirroring in Qt?