[PATCH v3 2/6] iio: pressure: Introduce new cleanup routines to BMP280 driver *_raw() functions

[Vasileios Amoiridis <vassilisamir@gmail.com>]

Introduce the new linux/cleanup.h with the guard(mutex) functionality
in the {read/write}_raw() functions

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Suggested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Vasileios Amoiridis <vassilisamir@gmail.com>
---
 drivers/iio/pressure/bmp280-core.c | 125 +++++++++++++----------------
 1 file changed, 58 insertions(+), 67 deletions(-)

diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
index 871b2214121b..f7a13ff6f26c 100644
--- a/drivers/iio/pressure/bmp280-core.c
+++ b/drivers/iio/pressure/bmp280-core.c
@@ -460,77 +460,74 @@ static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2)
 	return IIO_VAL_INT;
 }
 
-static int bmp280_read_raw(struct iio_dev *indio_dev,
-			   struct iio_chan_spec const *chan,
-			   int *val, int *val2, long mask)
+static int bmp280_read_raw_guarded(struct iio_dev *indio_dev,
+				   struct iio_chan_spec const *chan,
+				   int *val, int *val2, long mask)
 {
 	struct bmp280_data *data = iio_priv(indio_dev);
-	int ret;
 
-	pm_runtime_get_sync(data->dev);
-	mutex_lock(&data->lock);
+	guard(mutex)(&data->lock);
 
 	switch (mask) {
 	case IIO_CHAN_INFO_PROCESSED:
 		switch (chan->type) {
 		case IIO_HUMIDITYRELATIVE:
-			ret = data->chip_info->read_humid(data, val, val2);
-			break;
+			return data->chip_info->read_humid(data, val, val2);
 		case IIO_PRESSURE:
-			ret = data->chip_info->read_press(data, val, val2);
-			break;
+			return data->chip_info->read_press(data, val, val2);
 		case IIO_TEMP:
-			ret = data->chip_info->read_temp(data, val, val2);
-			break;
+			return data->chip_info->read_temp(data, val, val2);
 		default:
-			ret = -EINVAL;
-			break;
+			return -EINVAL;
 		}
-		break;
+		return 0;
 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
 		switch (chan->type) {
 		case IIO_HUMIDITYRELATIVE:
 			*val = 1 << data->oversampling_humid;
-			ret = IIO_VAL_INT;
-			break;
+			return IIO_VAL_INT;
 		case IIO_PRESSURE:
 			*val = 1 << data->oversampling_press;
-			ret = IIO_VAL_INT;
-			break;
+			return IIO_VAL_INT;
 		case IIO_TEMP:
 			*val = 1 << data->oversampling_temp;
-			ret = IIO_VAL_INT;
-			break;
+			return IIO_VAL_INT;
 		default:
-			ret = -EINVAL;
-			break;
+			return -EINVAL;
 		}
-		break;
+		return 0;
 	case IIO_CHAN_INFO_SAMP_FREQ:
 		if (!data->chip_info->sampling_freq_avail) {
-			ret = -EINVAL;
-			break;
+			return -EINVAL;
 		}
 
 		*val = data->chip_info->sampling_freq_avail[data->sampling_freq][0];
 		*val2 = data->chip_info->sampling_freq_avail[data->sampling_freq][1];
-		ret = IIO_VAL_INT_PLUS_MICRO;
-		break;
+		return IIO_VAL_INT_PLUS_MICRO;
 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
 		if (!data->chip_info->iir_filter_coeffs_avail) {
-			ret = -EINVAL;
-			break;
+			return -EINVAL;
 		}
 
 		*val = (1 << data->iir_filter_coeff) - 1;
-		ret = IIO_VAL_INT;
-		break;
+		return IIO_VAL_INT;
 	default:
-		ret = -EINVAL;
-		break;
+		return -EINVAL;
 	}
 
-	mutex_unlock(&data->lock);
+	return 0;
+}
+
+
+static int bmp280_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val, int *val2, long mask)
+{
+	struct bmp280_data *data = iio_priv(indio_dev);
+	int ret;
+
+	pm_runtime_get_sync(data->dev);
+	ret = bmp280_read_raw_guarded(indio_dev, chan, val, val2, mask);
 	pm_runtime_mark_last_busy(data->dev);
 	pm_runtime_put_autosuspend(data->dev);
 
@@ -662,13 +659,13 @@ static int bmp280_write_iir_filter_coeffs(struct bmp280_data *data, int val)
 	return -EINVAL;
 }
 
-static int bmp280_write_raw(struct iio_dev *indio_dev,
-			    struct iio_chan_spec const *chan,
-			    int val, int val2, long mask)
+static int bmp280_write_raw_guarded(struct iio_dev *indio_dev,
+				    struct iio_chan_spec const *chan,
+				    int val, int val2, long mask)
 {
 	struct bmp280_data *data = iio_priv(indio_dev);
-	int ret = 0;
 
+	guard(mutex)(&data->lock);
 	/*
 	 * Helper functions to update sensor running configuration.
 	 * If an error happens applying new settings, will try restore
@@ -677,46 +674,40 @@ static int bmp280_write_raw(struct iio_dev *indio_dev,
 	 */
 	switch (mask) {
 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
-		pm_runtime_get_sync(data->dev);
-		mutex_lock(&data->lock);
 		switch (chan->type) {
 		case IIO_HUMIDITYRELATIVE:
-			ret = bmp280_write_oversampling_ratio_humid(data, val);
-			break;
+			return bmp280_write_oversampling_ratio_humid(data, val);
 		case IIO_PRESSURE:
-			ret = bmp280_write_oversampling_ratio_press(data, val);
-			break;
+			return bmp280_write_oversampling_ratio_press(data, val);
 		case IIO_TEMP:
-			ret = bmp280_write_oversampling_ratio_temp(data, val);
-			break;
+			return bmp280_write_oversampling_ratio_temp(data, val);
 		default:
-			ret = -EINVAL;
-			break;
+			return -EINVAL;
 		}
-		mutex_unlock(&data->lock);
-		pm_runtime_mark_last_busy(data->dev);
-		pm_runtime_put_autosuspend(data->dev);
-		break;
+		return 0;
 	case IIO_CHAN_INFO_SAMP_FREQ:
-		pm_runtime_get_sync(data->dev);
-		mutex_lock(&data->lock);
-		ret = bmp280_write_sampling_frequency(data, val, val2);
-		mutex_unlock(&data->lock);
-		pm_runtime_mark_last_busy(data->dev);
-		pm_runtime_put_autosuspend(data->dev);
-		break;
+		return bmp280_write_sampling_frequency(data, val, val2);
 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
-		pm_runtime_get_sync(data->dev);
-		mutex_lock(&data->lock);
-		ret = bmp280_write_iir_filter_coeffs(data, val);
-		mutex_unlock(&data->lock);
-		pm_runtime_mark_last_busy(data->dev);
-		pm_runtime_put_autosuspend(data->dev);
-		break;
+		return bmp280_write_iir_filter_coeffs(data, val);
 	default:
 		return -EINVAL;
 	}
 
+	return 0;
+}
+
+static int bmp280_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int val, int val2, long mask)
+{
+	struct bmp280_data *data = iio_priv(indio_dev);
+	int ret = 0;
+
+	pm_runtime_get_sync(data->dev);
+	ret = bmp280_write_raw_guarded(indio_dev, chan, val, val2, mask);
+	pm_runtime_mark_last_busy(data->dev);
+	pm_runtime_put_autosuspend(data->dev);
+
 	return ret;
 }
 
-- 
2.25.1