[PATCH 02/37] iio: chemical: ccs811: Factor out handling of read of IIO_INFO_RAW to simplify error paths.

[Jonathan Cameron <jic23@kernel.org>]

From: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Factor out the implementation of this part of read_raw() and use
guard() to allow direct returns, simplifying both error and non error
paths.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 drivers/iio/chemical/ccs811.c | 72 ++++++++++++++++++-----------------
 1 file changed, 37 insertions(+), 35 deletions(-)

diff --git a/drivers/iio/chemical/ccs811.c b/drivers/iio/chemical/ccs811.c
index 451fb65dbe60..75b0cb05dd86 100644
--- a/drivers/iio/chemical/ccs811.c
+++ b/drivers/iio/chemical/ccs811.c
@@ -15,6 +15,7 @@
  * 4. Read error register and put the information in logs
  */
 
+#include <linux/cleanup.h>
 #include <linux/delay.h>
 #include <linux/gpio/consumer.h>
 #include <linux/i2c.h>
@@ -214,6 +215,40 @@ static int ccs811_get_measurement(struct ccs811_data *data)
 	return ret;
 }
 
+static int ccs811_read_info_raw(struct ccs811_data *data,
+				struct iio_chan_spec const *chan,
+				int *val, int mask)
+{
+	int ret;
+
+	guard(mutex)(&data->lock);
+	ret = ccs811_get_measurement(data);
+	if (ret < 0)
+		return ret;
+
+	switch (chan->type) {
+	case IIO_VOLTAGE:
+		*val = be16_to_cpu(data->buffer.raw_data) & CCS811_VOLTAGE_MASK;
+		return IIO_VAL_INT;
+	case IIO_CURRENT:
+		*val = be16_to_cpu(data->buffer.raw_data) >> 10;
+		return IIO_VAL_INT;
+	case IIO_CONCENTRATION:
+		switch (chan->channel2) {
+		case IIO_MOD_CO2:
+			*val = be16_to_cpu(data->buffer.co2);
+			return IIO_VAL_INT;
+		case IIO_MOD_VOC:
+			*val = be16_to_cpu(data->buffer.voc);
+			return IIO_VAL_INT;
+		default:
+			return -EINVAL;
+		}
+	default:
+		return -EINVAL;
+	}
+}
+
 static int ccs811_read_raw(struct iio_dev *indio_dev,
 			   struct iio_chan_spec const *chan,
 			   int *val, int *val2, long mask)
@@ -226,42 +261,9 @@ static int ccs811_read_raw(struct iio_dev *indio_dev,
 		ret = iio_device_claim_direct_mode(indio_dev);
 		if (ret)
 			return ret;
-		mutex_lock(&data->lock);
-		ret = ccs811_get_measurement(data);
-		if (ret < 0) {
-			mutex_unlock(&data->lock);
-			iio_device_release_direct_mode(indio_dev);
-			return ret;
-		}
 
-		switch (chan->type) {
-		case IIO_VOLTAGE:
-			*val = be16_to_cpu(data->buffer.raw_data) &
-					   CCS811_VOLTAGE_MASK;
-			ret = IIO_VAL_INT;
-			break;
-		case IIO_CURRENT:
-			*val = be16_to_cpu(data->buffer.raw_data) >> 10;
-			ret = IIO_VAL_INT;
-			break;
-		case IIO_CONCENTRATION:
-			switch (chan->channel2) {
-			case IIO_MOD_CO2:
-				*val = be16_to_cpu(data->buffer.co2);
-				ret =  IIO_VAL_INT;
-				break;
-			case IIO_MOD_VOC:
-				*val = be16_to_cpu(data->buffer.voc);
-				ret = IIO_VAL_INT;
-				break;
-			default:
-				ret = -EINVAL;
-			}
-			break;
-		default:
-			ret = -EINVAL;
-		}
-		mutex_unlock(&data->lock);
+		ret = ccs811_read_info_raw(data, chan, val, mask);
+
 		iio_device_release_direct_mode(indio_dev);
 
 		return ret;
-- 
2.48.1