The maximum possible value for the relative humidity is 55575 (100%RH). This value, if shifted right by 2 bits, uses 14 bits and masking it with a 12 bit mask removes 2 meaningful bits. The masking has been replaced with a range check that sets the minimum value at 786 (0%RH) and the maximum at 13893 (99.998%RH). Signed-off-by: Nicola Corna <nicola@xxxxxxxxxx> Reviewed-by: Hartmut Knaack <knaack.h@xxxxxx> --- drivers/iio/humidity/si7020.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/iio/humidity/si7020.c b/drivers/iio/humidity/si7020.c index fa3b809..06e6659 100644 --- a/drivers/iio/humidity/si7020.c +++ b/drivers/iio/humidity/si7020.c @@ -57,8 +57,12 @@ static int si7020_read_raw(struct iio_dev *indio_dev, if (ret < 0) return ret; *val = ret >> 2; + /* + * Humidity values can slightly exceed the 0-100%RH + * range and should be corrected by software + */ if (chan->type == IIO_HUMIDITYRELATIVE) - *val &= GENMASK(11, 0); + clamp_val(*val, 786, 13893); return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: if (chan->type == IIO_TEMP) -- 2.5.0 -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
