1. You cannot use eglfs or linuxfb together with GNOME (so with X11) - there can be only one thing displayed on the framebuffer (fb) - either your gnome desktop or your application. I assume that when using linuxfb your application takes over the framebuffer, but gnome is stealing your touch events (as it do not know about your app at all).
2. To compile xcb plugin you need to have all the dependencies. Check the qtbase/src/plugins/platforms/xcb/README file. You have to have at least development package of libxcb, as XCB_ATOM_WM_NAME is defined in xproto.h
3. Another thing is that qtbase/mkspecs/devices/linux-imx6-g++/ files might need some modifications to support the X11. There is -DEGL_API_FB=1 which is good for eglfs but vivante has different libraries and different declarations in EGL/eglvivante.h for FB, DFB and X11.
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