So far we used the wrong opcodes to access the DSI registers, so the
register writes during DSI programming didn't actually succeed and left
the registers unchanged. This wasn't a problem for the initial modeset,
where the BIOS-programmed values happened to work, but after resuming
from s0ix these registers are reset and failing to program them results
in a blank screen.
Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>