USB telem from Pixhawk? Rotate RPI screen in config?

Greetings fellow nerds,
I have a question and a dilemma. Can you just stream Mavlink telemetry data from the USB port on a Pixhawk to the RPI? And the dilemma is I mounted a 7 inch touch screen RPI to my controller and the case would only allow it to mount with the screen displaying upside down. Is there something in the config files I can change to flip the screen 180 degrees?