On the i.mx6, fb0 can be used as the background and fb1 can be used as a foreground. I currently have video playing on fb0 using video4linux and want to overlay some controls on fb1 using QT5 and EGLFS. However, I cannot get QT5 to use fb1. I dug down into the QPA for EGLFS and found it hard coded to use /dev/fb0. However, when I changed it to /dev/fb1 QT still used /dev/fb0. I even tried changing the hard coded value to /dev/fb10 which resulted in an error message and QT proceeded to use /dev/fb0 anyway. If I force my video4linux app to use fb1(in a reduced window size) and then run my QT app I can see both on the screen. However, I need the video to be full screen with the controls over layed. Can this be done with QT?
