haltwo_read
while (haltwo_read(sc, ctl, HAL2_REG_CTL_ISR) & HAL2_ISR_TSTATUS)
while (haltwo_read(sc, ctl, HAL2_REG_CTL_ISR) & HAL2_ISR_TSTATUS)
*low = haltwo_read(sc, ctl, HAL2_REG_CTL_IDR0);
*high = haltwo_read(sc, ctl, HAL2_REG_CTL_IDR1);
rev = haltwo_read(sc, ctl, HAL2_REG_CTL_REV);