[PATCH v3 10/10] iio: accel: mma8452: use guard() to release mutexes

[Sanjay Chitroda <sanjayembeddedse@gmail.com>]

From: Sanjay Chitroda <sanjayembeddedse@gmail.com>

Replace explicit mutex_lock() and mutex_unlock() with the guard() and
scoped_guard() macro for cleaner and safer mutex handling.

Signed-off-by: Sanjay Chitroda <sanjayembeddedse@gmail.com>
---
Changes in v3:
- Following input from Jonathan extended mutex scope for
  IIO_CHAN_INFO_RAW case to include math operation under lock
- Link to v2: https://lore.kernel.org/all/20260422165643.2148195-7-sanjayembedded@gmail.com/
---
 drivers/iio/accel/mma8452.c | 29 +++++++++++------------------
 1 file changed, 11 insertions(+), 18 deletions(-)

diff --git a/drivers/iio/accel/mma8452.c b/drivers/iio/accel/mma8452.c
index 3bc53cfdac24..1370674d71c6 100644
--- a/drivers/iio/accel/mma8452.c
+++ b/drivers/iio/accel/mma8452.c
@@ -18,6 +18,7 @@
  * TODO: orientation events
  */
 
+#include <linux/cleanup.h>
 #include <linux/delay.h>
 #include <linux/i2c.h>
 #include <linux/mod_devicetable.h>
@@ -478,10 +479,9 @@ static int mma8452_read_raw(struct iio_dev *indio_dev,
 		IIO_DEV_ACQUIRE_DIRECT_MODE(indio_dev, claim);
 		if (IIO_DEV_ACQUIRE_FAILED(claim))
 			return -EBUSY;
+		guard(mutex)(&data->lock);
 
-		mutex_lock(&data->lock);
 		ret = mma8452_read(data, buffer);
-		mutex_unlock(&data->lock);
 		if (ret < 0)
 			return ret;
 
@@ -579,36 +579,30 @@ static int mma8452_change_config(struct mma8452_data *data, u8 reg, u8 val)
 	int ret;
 	int is_active;
 
-	mutex_lock(&data->lock);
+	guard(mutex)(&data->lock);
 
 	is_active = mma8452_is_active(data);
-	if (is_active < 0) {
-		ret = is_active;
-		goto fail;
-	}
+	if (is_active < 0)
+		return is_active;
 
 	/* config can only be changed when in standby */
 	if (is_active > 0) {
 		ret = mma8452_standby(data);
 		if (ret < 0)
-			goto fail;
+			return ret;
 	}
 
 	ret = i2c_smbus_write_byte_data(data->client, reg, val);
 	if (ret < 0)
-		goto fail;
+		return ret;
 
 	if (is_active > 0) {
 		ret = mma8452_active(data);
 		if (ret < 0)
-			goto fail;
+			return ret;
 	}
 
-	ret = 0;
-fail:
-	mutex_unlock(&data->lock);
-
-	return ret;
+	return 0;
 }
 
 static int mma8452_set_power_mode(struct mma8452_data *data, u8 mode)
@@ -1730,9 +1724,8 @@ static int mma8452_runtime_suspend(struct device *dev)
 	struct mma8452_data *data = iio_priv(indio_dev);
 	int ret;
 
-	mutex_lock(&data->lock);
-	ret = mma8452_standby(data);
-	mutex_unlock(&data->lock);
+	scoped_guard(mutex, &data->lock)
+		ret = mma8452_standby(data);
 	if (ret < 0) {
 		dev_err(dev, "powering off device failed\n");
 		return -EAGAIN;
-- 
2.34.1