ADIS16550_REG_SYNC_SCALE
ret = __adis_read_reg_16(&st->adis, ADIS16550_REG_SYNC_SCALE, &sync_scale);
ret = __adis_write_reg_16(&st->adis, ADIS16550_REG_SYNC_SCALE,
ret = adis_write_reg_16(&st->adis, ADIS16550_REG_SYNC_SCALE,