diff --git a/drivers/iio/proximity/as3935.c b/drivers/iio/proximity/as3935.c
index 5e780ef206f3..8349cc0fdf66 100644
--- a/drivers/iio/proximity/as3935.c
+++ b/drivers/iio/proximity/as3935.c
@@ -330,7 +330,7 @@ static int as3935_probe(struct spi_device *spi)
 		return -EINVAL;
 	}
 
-	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(st));
+	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
 	if (!indio_dev)
 		return -ENOMEM;