It's always a bad idea to poll on HW bits without a timeout.

The i.MX28 RTC can be easily brought into a state in which the RTC is
not running (until after a power-on-reset) and thus the status bits
which are polled in the driver won't ever change.

This patch prevents the kernel from getting stuck in this case.
Signed-off-by: NLothar Waßmann <LW@KARO-electronics.de>
Acked-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>