The platform driver is used to access the features provided by the
Videocore mboxes, i.e., power configuration and framebuffer setup. The
framebuffer driver uses the platform interface to setup a screen mode of
1024x768.
At the current stage, the USB HID and storage drivers are prinicpally
working but not stable. If interrupts are not processed fast enough,
devices will get sporadically disconnected.
The USB host-controller driver is not part of the normal Linux kernel.
For this reason, we need to download it separately. There exists a
'prepare_rpi' rule in the 'dde_linux/Makefile' to automate this process.