ATH9K_BEACON_PERIOD
intval = conf.beacon_interval & ATH9K_BEACON_PERIOD;
TU_TO_USEC(bs->bs_intval & ATH9K_BEACON_PERIOD));
TU_TO_USEC(bs->bs_intval & ATH9K_BEACON_PERIOD));
beaconintval = bs->bs_intval & ATH9K_BEACON_PERIOD;