staging: iio: ad7746: Improve unlocking of a mutex in ad7746_start_calib()

* Add a jump target so that a call of the function "mutex_unlock" is stored
  only twice in this function implementation.

* Replace two calls by goto statements.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/staging/iio/cdc/ad7746.c b/drivers/staging/iio/cdc/ad7746.c
index a124853..c4a8647 100644 (file)
--- a/drivers/staging/iio/cdc/ad7746.c
+++ b/drivers/staging/iio/cdc/ad7746.c
@@ -302,23 +302,24 @@ static inline ssize_t ad7746_start_calib(struct device *dev,
        mutex_lock(&chip->lock);
        regval |= chip->config;
        ret = i2c_smbus_write_byte_data(chip->client, AD7746_REG_CFG, regval);
-       if (ret < 0) {
-               mutex_unlock(&chip->lock);
-               return ret;
-       }
+       if (ret < 0)
+               goto unlock;
 
        do {
                msleep(20);
                ret = i2c_smbus_read_byte_data(chip->client, AD7746_REG_CFG);
-               if (ret < 0) {
-                       mutex_unlock(&chip->lock);
-                       return ret;
-               }
+               if (ret < 0)
+                       goto unlock;
+
        } while ((ret == regval) && timeout--);
 
        mutex_unlock(&chip->lock);
 
        return len;
+
+unlock:
+       mutex_unlock(&chip->lock);
+       return ret;
 }
 
 static ssize_t ad7746_start_offset_calib(struct device *dev,