SSTS_DREG_EMPTY
SSTS_DREG_EMPTY) != 0)
SSTS_DREG_EMPTY) != 0)
(sstat & SSTS_DREG_EMPTY) == 0)
(sstat & SSTS_DREG_EMPTY) != 0)
if ((bus_space_read_1(iot, ioh, SSTS) & SSTS_DREG_EMPTY) == 0)
while (hd->scsi_ssts & SSTS_DREG_EMPTY) {