counts_per_uvi depends on the current value of gain and resolution. Hence, we cannot use the hardcoded value 96. The `counts_per_uvi` function gives the count based on the current gain and resolution (integration time). Signed-off-by: Abhash Jha <abhashkumarjha123@xxxxxxxxx> --- drivers/iio/light/ltr390.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/iio/light/ltr390.c b/drivers/iio/light/ltr390.c index 953c1ed3d..37a017843 100644 --- a/drivers/iio/light/ltr390.c +++ b/drivers/iio/light/ltr390.c @@ -46,6 +46,8 @@ #define LTR390_UVS_MODE BIT(3) #define LTR390_SENSOR_ENABLE BIT(1) +#define LTR390_FRACTIONAL_PRECISION 100 + /* * At 20-bit resolution (integration time: 400ms) and 18x gain, 2300 counts of * the sensor are equal to 1 UV Index [Datasheet Page#8]. @@ -120,6 +122,16 @@ static int ltr390_set_mode(struct ltr390_data *data, enum ltr390_mode mode) return 0; } +static int ltr390_counts_per_uvi(struct ltr390_data *data) +{ + int orig_gain = 18; + int orig_int_time = 400; + int divisor = orig_gain * orig_int_time; + int gain = data->gain; + + return DIV_ROUND_CLOSEST(23 * gain * data->int_time_us, 10 * divisor); +} + static int ltr390_read_raw(struct iio_dev *iio_device, struct iio_chan_spec const *chan, int *val, int *val2, long mask) @@ -164,8 +176,8 @@ static int ltr390_read_raw(struct iio_dev *iio_device, if (ret < 0) return ret; - *val = LTR390_WINDOW_FACTOR; - *val2 = LTR390_COUNTS_PER_UVI; + *val = LTR390_WINDOW_FACTOR * LTR390_FRACTIONAL_PRECISION; + *val2 = ltr390_counts_per_uvi(data); return IIO_VAL_FRACTIONAL; case IIO_INTENSITY: -- 2.43.0