iio: humidity: hdc100x: Use guard(mutex) to simplify code flow

By using autoreleasing on the lock a number of paths can use
direct returns allow earlier exit from functions.

Reviewed-by: David Lechner <dlechner@baylibre.com>
Reviewed-by: Marcelo Schmitt <marcelo.schmitt1@gmail.com>
Link: https://patch.msgid.link/20250331121317.1694135-11-jic23@kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/humidity/hdc100x.c b/drivers/iio/humidity/hdc100x.c
index a303f70..fb85844 100644 (file)
--- a/drivers/iio/humidity/hdc100x.c
+++ b/drivers/iio/humidity/hdc100x.c
@@ -13,6 +13,7 @@
  * https://www.ti.com/product/HDC1080/datasheet
  */
 
+#include <linux/cleanup.h>
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/mod_devicetable.h>
@@ -206,26 +207,21 @@ static int hdc100x_read_raw(struct iio_dev *indio_dev,
        case IIO_CHAN_INFO_RAW: {
                int ret;
 
-               mutex_lock(&data->lock);
+               guard(mutex)(&data->lock);
                if (chan->type == IIO_CURRENT) {
                        *val = hdc100x_get_heater_status(data);
-                       ret = IIO_VAL_INT;
-               } else {
-                       ret = iio_device_claim_direct_mode(indio_dev);
-                       if (ret) {
-                               mutex_unlock(&data->lock);
-                               return ret;
-                       }
-
-                       ret = hdc100x_get_measurement(data, chan);
-                       iio_device_release_direct_mode(indio_dev);
-                       if (ret >= 0) {
-                               *val = ret;
-                               ret = IIO_VAL_INT;
-                       }
+                       return IIO_VAL_INT;
                }
-               mutex_unlock(&data->lock);
-               return ret;
+               ret = iio_device_claim_direct_mode(indio_dev);
+               if (ret)
+                       return ret;
+
+               ret = hdc100x_get_measurement(data, chan);
+               iio_device_release_direct_mode(indio_dev);
+               if (ret < 0)
+                       return ret;
+               *val = ret;
+               return IIO_VAL_INT;
        }
        case IIO_CHAN_INFO_INT_TIME:
                *val = 0;
@@ -256,26 +252,23 @@ static int hdc100x_write_raw(struct iio_dev *indio_dev,
                             int val, int val2, long mask)
 {
        struct hdc100x_data *data = iio_priv(indio_dev);
-       int ret = -EINVAL;
 
        switch (mask) {
-       case IIO_CHAN_INFO_INT_TIME:
+       case IIO_CHAN_INFO_INT_TIME: {
                if (val != 0)
                        return -EINVAL;
 
-               mutex_lock(&data->lock);
-               ret = hdc100x_set_it_time(data, chan->address, val2);
-               mutex_unlock(&data->lock);
-               return ret;
-       case IIO_CHAN_INFO_RAW:
+               guard(mutex)(&data->lock);
+               return hdc100x_set_it_time(data, chan->address, val2);
+       }
+       case IIO_CHAN_INFO_RAW: {
                if (chan->type != IIO_CURRENT || val2 != 0)
                        return -EINVAL;
 
-               mutex_lock(&data->lock);
-               ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_HEATER_EN,
-                                       val ? HDC100X_REG_CONFIG_HEATER_EN : 0);
-               mutex_unlock(&data->lock);
-               return ret;
+               guard(mutex)(&data->lock);
+               return hdc100x_update_config(data, HDC100X_REG_CONFIG_HEATER_EN,
+                                            val ? HDC100X_REG_CONFIG_HEATER_EN : 0);
+       }
        default:
                return -EINVAL;
        }
@@ -284,27 +277,19 @@ static int hdc100x_write_raw(struct iio_dev *indio_dev,
 static int hdc100x_buffer_postenable(struct iio_dev *indio_dev)
 {
        struct hdc100x_data *data = iio_priv(indio_dev);
-       int ret;
 
        /* Buffer is enabled. First set ACQ Mode, then attach poll func */
-       mutex_lock(&data->lock);
-       ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE,
-                                   HDC100X_REG_CONFIG_ACQ_MODE);
-       mutex_unlock(&data->lock);
-
-       return ret;
+       guard(mutex)(&data->lock);
+       return hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE,
+                                    HDC100X_REG_CONFIG_ACQ_MODE);
 }
 
 static int hdc100x_buffer_predisable(struct iio_dev *indio_dev)
 {
        struct hdc100x_data *data = iio_priv(indio_dev);
-       int ret;
 
-       mutex_lock(&data->lock);
-       ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE, 0);
-       mutex_unlock(&data->lock);
-
-       return ret;
+       guard(mutex)(&data->lock);
+       return hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE, 0);
 }
 
 static const struct iio_buffer_setup_ops hdc_buffer_setup_ops = {