[PATCH v2 1/1] iio: adc: ad4170-4: Correctly update filter_fs after filter type change

[Marcelo Schmitt]

Previously, the driver was directly using the filter type value to update
the filter frequency (filter_fs) configuration. That caused the driver to
switch to the lowest filter_fs configuration (highest sampling frequency)
on every update to the filter type. Correct the filter_fs collateral update
by clamping it to the range of supported values instead of mistakenly
using the filter type to update the filter_fs.

Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Link: https://lore.kernel.org/linux-iio/c6e54942-5b42-484b-be53-9d4606fd25c4@sabinyo.mountain/
Suggested-by: Jonathan Cameron <jic23@xxxxxxxxxx>
Fixes: 8ab7434734cd ("iio: adc: ad4170-4: Add digital filter and sample frequency config support")
Signed-off-by: Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx>
---
Hi, this is the same fix as the fix provided in implied v1 patch but with the
difference of doing it the way Markus suggested in reply to v1.
I have a slight preference for v1 since that one keeps code contained within
80 columns. Though, totally fine with whatever version of the fix gets picked up.

Change log v1 (implied) -> v2
- Replaces if by use of ternary operator as suggested by Markus in reply to v1.
- Fixed commit log typo: colateral -> collateral
- Fixed commit log typo: clampling -> clamping

Thanks,
Marcelo

 drivers/iio/adc/ad4170-4.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/iio/adc/ad4170-4.c b/drivers/iio/adc/ad4170-4.c
index 6cd84d6fb08b..2e61f9a9a1ef 100644
--- a/drivers/iio/adc/ad4170-4.c
+++ b/drivers/iio/adc/ad4170-4.c
@@ -879,12 +879,11 @@ static int ad4170_set_filter_type(struct iio_dev *indio_dev,
 		if (!iio_device_claim_direct(indio_dev))
 			return -EBUSY;
 
-		if (val == AD4170_SINC5_AVG || val == AD4170_SINC3)
-			setup->filter_fs = clamp(val, AD4170_SINC3_MIN_FS,
-						 AD4170_SINC3_MAX_FS);
-		else
-			setup->filter_fs = clamp(val, AD4170_SINC5_MIN_FS,
-						 AD4170_SINC5_MAX_FS);
+		setup->filter_fs = (val == AD4170_SINC5_AVG || val == AD4170_SINC3)
+				    ? clamp(setup->filter_fs,
+					    AD4170_SINC3_MIN_FS, AD4170_SINC3_MAX_FS)
+				    : clamp(setup->filter_fs,
+					    AD4170_SINC5_MIN_FS, AD4170_SINC5_MAX_FS);
 
 		setup->filter &= ~AD4170_FILTER_FILTER_TYPE_MSK;
 		setup->filter |= FIELD_PREP(AD4170_FILTER_FILTER_TYPE_MSK,

base-commit: cd2731444ee4e35db76f4fb587f12d327eec5446
-- 
2.47.2