[PATCH] iio: adc: ad4062: Add missing IS_ERR() check

[Ethan Tidmore]

In the function ad4062_sizeof_storagebits() iio_get_current_scan_type()
is called which can return an error pointer and is not checked for it.
Also the function ad4062_sizeof_storagebits() returns type size_t but,
is only used once and the variable assigned from it is type u8.

Add check for error pointer in ad4062_sizeof_storagebits() and change
return type to int so the error code can be properly propagated and then
checked.

Fixes: 23cc92280302d ("iio: adc: ad4062: Add IIO Trigger support")
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <error27@xxxxxxxxx>
Closes: https://lore.kernel.org/r/202512280539.AholFF7m-lkp@xxxxxxxxx/
Signed-off-by: Ethan Tidmore <ethantidmore06@xxxxxxxxx>
---
 drivers/iio/adc/ad4062.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/adc/ad4062.c b/drivers/iio/adc/ad4062.c
index dd4ad32aa6f5..c864de3b46ba 100644
--- a/drivers/iio/adc/ad4062.c
+++ b/drivers/iio/adc/ad4062.c
@@ -1199,11 +1199,14 @@ static int ad4062_write_event_value(struct iio_dev *indio_dev,
  * The AD4062 in burst averaging mode increases realbits from 16-bits to
  * 20-bits, increasing the storagebits from 16-bits to 32-bits.
  */
-static inline size_t ad4062_sizeof_storagebits(struct ad4062_state *st)
+static inline int ad4062_sizeof_storagebits(struct ad4062_state *st)
 {
 	const struct iio_scan_type *scan_type =
 		iio_get_current_scan_type(st->indio_dev, st->chip->channels);
 
+	if (IS_ERR(scan_type))
+		return PTR_ERR(scan_type);
+
 	return BITS_TO_BYTES(scan_type->storagebits);
 }
 
@@ -1233,7 +1236,12 @@ static int pm_ad4062_triggered_buffer_postenable(struct ad4062_state *st)
 	if (ret)
 		return ret;
 
-	st->conv_sizeof = ad4062_sizeof_storagebits(st);
+	ret = ad4062_sizeof_storagebits(st);
+	if (ret < 0)
+		return ret;
+
+	st->conv_sizeof = ret;
+
 	st->conv_addr = ad4062_get_conv_addr(st, st->conv_sizeof);
 	/* CONV_READ requires read to trigger first sample. */
 	struct i3c_xfer xfer_sample[2] = {
-- 
2.53.0