ad3552r_get_ref_voltage
EXPORT_SYMBOL_NS_GPL(ad3552r_get_ref_voltage, "IIO_AD3552R");
ret = ad3552r_get_ref_voltage(st->dev, &val);
err = ad3552r_get_ref_voltage(dev, &val);
int ad3552r_get_ref_voltage(struct device *dev, u32 *val);