[PATCH v2 1/3] iio: adc: ad7192: Fix null pointer dereference on probe

[Fabrizio Lamarque <fl.scratchpad@xxxxxxxxx>]

Pointer to indio_dev structure is obtained via spi_get_drvdata() at
the beginning of function ad7192_setup(), but the spi->dev->driver_data
member is not initialized, hence a NULL pointer is returned.

Fixed by changing ad7192_setup() signature to take pointer to struct
iio_dev, and get ad7192_state pointer via st = iio_priv(indio_dev);

Fixes: bd5dcdeb3fd0 iio: adc: ad7192: convert to device-managed functions
Signed-off-by: Fabrizio Lamarque <fl.scratchpad@xxxxxxxxx>
---
Changes in v2: obtained ad7192_state from iio_dev pointer as suggested
by Jonathan, removed Reviewed-by since the entire patch changed its
content.

 drivers/iio/adc/ad7192.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/adc/ad7192.c b/drivers/iio/adc/ad7192.c
index 55a6ab591016..94a9cf34a255 100644
--- a/drivers/iio/adc/ad7192.c
+++ b/drivers/iio/adc/ad7192.c
@@ -380,9 +380,9 @@ static int ad7192_of_clock_select(struct ad7192_state *st)
  return clock_sel;
 }

-static int ad7192_setup(struct ad7192_state *st, struct device_node *np)
+static int ad7192_setup(struct iio_dev *indio_dev, struct device_node *np)
 {
- struct iio_dev *indio_dev = spi_get_drvdata(st->sd.spi);
+ struct ad7192_state *st = iio_priv(indio_dev);
  bool rej60_en, refin2_en;
  bool buf_en, bipolar, burnout_curr_en;
  unsigned long long scale_uv;
@@ -1073,7 +1073,7 @@ static int ad7192_probe(struct spi_device *spi)
  }
  }

- ret = ad7192_setup(st, spi->dev.of_node);
+ ret = ad7192_setup(indio_dev, spi->dev.of_node);
  if (ret)
  return ret;

--
2.34.1