https://github.com/Tasssadar/multirom/blob/master/lib/framebuffer_qcom_overlay.c#L298

The kernel (Linux 3.4.0) for the Fairphone 2 has the lower member. There should probably be a switch in the BoardConfig which one to take.

See PR #102

EDIT: Apparently I am not the only person with this issue - #97 also has a similar thing (although it's device specific and not switchable)