It's somehow common for devices to have portrait displays which are actually landscape displays installed rotated 90°.

This requires additional support at the linuxfb QPA level and possibly at higher levels.

• The QPA plugin needs to get an additional rotation parameter (to select e.g. 0/90/180/270) and report it back as faux-screen resolution (e.g. 400x300 rotated becomes 300x400)
• At some level compositing needs to apply rotations into the physical FB (i.e. the memory mapped region of /dev/fb0), for instance when copying the screen's FB into it. (Not sure why such a copy happens; will open a separate report for that.)