[PATCH 04/13] iio: adc: qcom-spmi-adc5: Use __free(fwnode_handle) to replace fwnode_handle_put() calls

[Jonathan Cameron <jic23@kernel.org>]

From: Jonathan Cameron <Jonathan.Cameron@huawei.com>

This use of the new cleanup.h scope based freeing infrastructure allows
us to exit directly from error conditions within the
device_for_each_child_node(dev, child) loop. On normal exit from that
loop no fwnode_handle reference will be held and the child pointer
will be NULL thus making the automatically run fwnode_handle_put() a
noop.

A slightly less convincing usecase than many as all the failure paths
are wrapped up in a call to a per fwnode_handle utility function.
The complexity in that function is sufficient that it makes sense to
factor it out even if it this new auto cleanup would enable simpler
returns if the code was inline at the call site. Hence I've left it alone.

Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Cc: Marijn Suijten <marijn.suijten@somainline.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 drivers/iio/adc/qcom-spmi-adc5.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/iio/adc/qcom-spmi-adc5.c b/drivers/iio/adc/qcom-spmi-adc5.c
index b6b612d733ff..36d3912d36df 100644
--- a/drivers/iio/adc/qcom-spmi-adc5.c
+++ b/drivers/iio/adc/qcom-spmi-adc5.c
@@ -825,7 +825,7 @@ static int adc5_get_fw_data(struct adc5_chip *adc)
 	const struct adc5_channels *adc_chan;
 	struct iio_chan_spec *iio_chan;
 	struct adc5_channel_prop prop, *chan_props;
-	struct fwnode_handle *child;
+	struct fwnode_handle *child __free(fwnode_handle) = NULL;
 	unsigned int index = 0;
 	int ret;
 
@@ -851,10 +851,8 @@ static int adc5_get_fw_data(struct adc5_chip *adc)
 
 	device_for_each_child_node(adc->dev, child) {
 		ret = adc5_get_fw_channel_data(adc, &prop, child, adc->data);
-		if (ret) {
-			fwnode_handle_put(child);
+		if (ret)
 			return ret;
-		}
 
 		prop.scale_fn_type =
 			adc->data->adc_chans[prop.channel].scale_fn_type;
-- 
2.43.0