mmc: tmio: only access registers above 0xff, if available
Not all tmio implementations have registers above oxff. Accessing
them on thise platforms is dangerous. In some cases it leads to
address wrapping to addresses below 0x100, which corrupts random
unrelated registers.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
authored by Guennadi Liakhovetski and committed by Chris Ball 69d1fe18 52c6182a