iio: adc: adrv9002: rearrange 'adrv9002_attr_show'

Follow the logic of the rest of the driver and just lock() the complete
function. This makes it simpler (and most of the settings need to be
locked anyways) in a following patch to add support for the initial
calibrations attribute.

Signed-off-by: Nuno Sa <nuno.sa@analog.com>

Author: nunojsa

drivers/iio/adc/navassa/adrv9002.c

@@ -552,46 +552,49 @@ static int adrv9002_fh_table_show(struct adrv9002_rf_phy *phy, char *buf, u64 ad
 {
 	adi_adrv9001_FhMode_e mode = phy->fh.mode;
 	adi_adrv9001_FhHopTable_e table;
-	int ret = -ENOTSUPP;
+	int ret;
 
-	mutex_lock(&phy->lock);
 	if (!phy->curr_profile->sysConfig.fhModeOn) {
 		dev_err(&phy->spi->dev, "Frequency hopping not enabled\n");
-		goto out_unlock;
+		return -ENOTSUPP;
 	}
 
 	if (address && mode != ADI_ADRV9001_FHMODE_LO_RETUNE_REALTIME_PROCESS_DUAL_HOP) {
 		dev_err(&phy->spi->dev, "HOP2 not supported! FH mode not in dual hop.\n");
-		goto out_unlock;
+		return -ENOTSUPP;
 	}
 
 	ret = api_call(phy, adi_adrv9001_fh_HopTable_Get, address, &table);
 	if (ret)
-		goto out_unlock;
-	mutex_unlock(&phy->lock);
+		return ret;
 
 	if (table >= ADRV9002_FH_TABLES_NR)
 		table = ADRV9002_FH_TABLES_NR;
 
 	return sysfs_emit(buf, "%s\n", adrv9002_hop_table[table]);
-out_unlock:
-	mutex_unlock(&phy->lock);
-	return ret;
 }
 
 static ssize_t adrv9002_attr_show(struct device *dev, struct device_attribute *attr, char *buf)
 {
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct adrv9002_rf_phy *phy = iio_priv(indio_dev);
 	struct iio_dev_attr *iio_attr = to_iio_dev_attr(attr);
+	int ret;
+
+	mutex_lock(&phy->lock);
 
 	switch (iio_attr->address) {
 	case ADRV9002_HOP_1_TABLE_SEL:
 	case ADRV9002_HOP_2_TABLE_SEL:
-		return adrv9002_fh_table_show(phy, buf, iio_attr->address);
+		ret = adrv9002_fh_table_show(phy, buf, iio_attr->address);
+		break;
 	default:
-		return -EINVAL;
+		ret = -EINVAL;
 	}
+
+	mutex_unlock(&phy->lock);
+
+	return ret;
 }
 
 static int adrv9002_fh_set(const struct adrv9002_rf_phy *phy, const char *buf, u64 address)