[PATCH] iio: adc: ad7779: Fix trigger reference leak in ad7779_setup_without_backend()

[Wentao Liang <vulab@iscas.ac.cn>]

The reference taken with iio_trigger_get() is only dropped by
iio_dev_release() when INDIO_BUFFER_TRIGGERED is set. If
devm_iio_triggered_buffer_setup() fails before setting that mode, the
reference acquired for indio_dev->trig leaks. Move the
iio_trigger_get() after the buffer setup succeeds.

Fixes: c9a3f8c7bfcb ("drivers: iio: adc: add support for ad777x family")
Cc: stable@vger.kernel.org
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
---
 drivers/iio/adc/ad7779.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/adc/ad7779.c b/drivers/iio/adc/ad7779.c
index 695cc79e78da..76834275b1ca 100644
--- a/drivers/iio/adc/ad7779.c
+++ b/drivers/iio/adc/ad7779.c
@@ -850,8 +850,6 @@ static int ad7779_setup_without_backend(struct ad7779_state *st, struct iio_dev
 	if (ret)
 		return ret;
 
-	indio_dev->trig = iio_trigger_get(st->trig);
-
 	init_completion(&st->completion);
 
 	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
@@ -861,6 +859,8 @@ static int ad7779_setup_without_backend(struct ad7779_state *st, struct iio_dev
 	if (ret)
 		return ret;
 
+	indio_dev->trig = iio_trigger_get(st->trig);
+
 	return ad7779_spi_write_mask(st, AD7779_REG_DOUT_FORMAT,
 				     AD7779_DCLK_CLK_DIV_MSK,
 				     FIELD_PREP(AD7779_DCLK_CLK_DIV_MSK, 7));
-- 
2.34.1