If the I2C port is completely broken then there is no point in trying to
continue with the transaction. This can happen if the pull-ups on the bus
are not working because they are in a power domain which is not currently
enabled.
Check the return value from i2c_unwedge() and return if it doesn't work.
Tidy up a few comments at the same time.
BUG=b:72129419
BRANCH=none
TEST=manually remove the check AP being off in sb_tsi_get_val() and see
that it quickly fails now, rather than hanging the EC for a while trying
the transaction.
Change-Id: I66ab52943459726537dfc74355f8aeaa5817dba5
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/956017
Reviewed-by: Edward Hill <ecgh@chromium.org>
Reviewed-by: Aaron Durbin <adurbin@google.com>
526cc1e4ed