The sinc4 filter has a factor 0.23 between Output Data Rate and f_{3dB}
and for sinc3 the factor is 0.272 according to the data sheets for
ad7124-4 (Rev. E.) and ad7124-8 (Rev. F).
Fixes: cef2760954cf ("iio: adc: ad7124: add 3db filter")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxx>
---
drivers/iio/adc/ad7124.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/iio/adc/ad7124.c b/drivers/iio/adc/ad7124.c
index 3ea81a98e455..7d5d84a07cae 100644
--- a/drivers/iio/adc/ad7124.c
+++ b/drivers/iio/adc/ad7124.c
@@ -301,9 +301,9 @@ static int ad7124_get_3db_filter_freq(struct ad7124_state *st,
switch (st->channels[channel].cfg.filter_type) {
case AD7124_SINC3_FILTER:
- return DIV_ROUND_CLOSEST(fadc * 230, 1000);
+ return DIV_ROUND_CLOSEST(fadc * 272, 1000);
case AD7124_SINC4_FILTER:
- return DIV_ROUND_CLOSEST(fadc * 262, 1000);
+ return DIV_ROUND_CLOSEST(fadc * 230, 1000);
default:
return -EINVAL;
}
--
2.47.1
