[PATCH v2 4/4] iio: magnetometer: rm3100: Use guard(mutex)() in rm3100_trigger_handler()

[Maxwell Doose]

Replace mutex_lock() and mutex_unlock() calls in
rm3100_trigger_handler() with the more modern guard(mutex)(). This will
help modernize the driver and bring it up-to-date with modern available
macros/functions.

Signed-off-by: Maxwell Doose <m32285159@xxxxxxxxx>
---
  v2:
 - Switched out scoped_guard() for guard(mutex)().
 - Because of the replacement of scoped_guard(), fixed an error due to
   gotos bypassing __attribute__((cleanup)).

 drivers/iio/magnetometer/rm3100-core.c | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/drivers/iio/magnetometer/rm3100-core.c b/drivers/iio/magnetometer/rm3100-core.c
index eb59ea8d5bf5..fdee82c1290f 100644
--- a/drivers/iio/magnetometer/rm3100-core.c
+++ b/drivers/iio/magnetometer/rm3100-core.c
@@ -459,11 +459,11 @@ static irqreturn_t rm3100_trigger_handler(int irq, void *p)
 	struct regmap *regmap = data->regmap;
 	int ret, i, bit;
 
-	mutex_lock(&data->lock);
+	guard(mutex)(&data->lock);
+
 	switch (scan_mask) {
 	case BIT(0) | BIT(1) | BIT(2):
 		ret = regmap_bulk_read(regmap, RM3100_REG_MX2, data->buffer, 9);
-		mutex_unlock(&data->lock);
 		if (ret < 0)
 			goto done;
 		/* Convert XXXYYYZZZxxx to XXXxYYYxZZZx. x for paddings. */
@@ -472,21 +472,18 @@ static irqreturn_t rm3100_trigger_handler(int irq, void *p)
 		break;
 	case BIT(0) | BIT(1):
 		ret = regmap_bulk_read(regmap, RM3100_REG_MX2, data->buffer, 6);
-		mutex_unlock(&data->lock);
 		if (ret < 0)
 			goto done;
 		memmove(data->buffer + 4, data->buffer + 3, 3);
 		break;
 	case BIT(1) | BIT(2):
 		ret = regmap_bulk_read(regmap, RM3100_REG_MY2, data->buffer, 6);
-		mutex_unlock(&data->lock);
 		if (ret < 0)
 			goto done;
 		memmove(data->buffer + 4, data->buffer + 3, 3);
 		break;
 	case BIT(0) | BIT(2):
 		ret = regmap_bulk_read(regmap, RM3100_REG_MX2, data->buffer, 9);
-		mutex_unlock(&data->lock);
 		if (ret < 0)
 			goto done;
 		memmove(data->buffer + 4, data->buffer + 6, 3);
@@ -495,12 +492,9 @@ static irqreturn_t rm3100_trigger_handler(int irq, void *p)
 		for_each_set_bit(bit, &scan_mask, mask_len) {
 			ret = regmap_bulk_read(regmap, RM3100_REG_MX2 + 3 * bit,
 					       data->buffer, 3);
-			if (ret < 0) {
-				mutex_unlock(&data->lock);
+			if (ret < 0)
 				goto done;
-			}
 		}
-		mutex_unlock(&data->lock);
 	}
 	/*
 	 * Always using the same buffer so that we wouldn't need to set the
-- 
2.53.0