[PATCH 4.14 47/53] iio: dln2: Check return value of devm_iio_trigger_register()

[Greg Kroah-Hartman]

From: Lars-Peter Clausen <lars@xxxxxxxxxx>

commit 90751fb9f224e0e1555b49a8aa9e68f6537e4cec upstream.

Registering a trigger can fail and the return value of
devm_iio_trigger_register() must be checked. Otherwise undefined behavior
can occur when the trigger is used.

Fixes: 7c0299e879dd ("iio: adc: Add support for DLN2 ADC")
Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20211101133043.6974-1-lars@xxxxxxxxxx
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/iio/adc/dln2-adc.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

--- a/drivers/iio/adc/dln2-adc.c
+++ b/drivers/iio/adc/dln2-adc.c
@@ -674,7 +674,11 @@ static int dln2_adc_probe(struct platfor
 	}
 	dln2->trig->ops = &dln2_adc_trigger_ops;
 	iio_trigger_set_drvdata(dln2->trig, dln2);
-	devm_iio_trigger_register(dev, dln2->trig);
+	ret = devm_iio_trigger_register(dev, dln2->trig);
+	if (ret) {
+		dev_err(dev, "failed to register trigger: %d\n", ret);
+		return ret;
+	}
 	iio_trigger_set_immutable(indio_dev, dln2->trig);
 
 	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,