staging:iio:ad799x: Report scale as fractional value

Move the complexity of calculating the fixed point scale to the core.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/staging/iio/adc/ad799x_core.c b/drivers/staging/iio/adc/ad799x_core.c
index 3f5142b..eb6a690 100644 (file)
--- a/drivers/staging/iio/adc/ad799x_core.c
+++ b/drivers/staging/iio/adc/ad799x_core.c
@@ -163,7 +163,6 @@ static int ad799x_read_raw(struct iio_dev *indio_dev,
 {
        int ret;
        struct ad799x_state *st = iio_priv(indio_dev);
-       unsigned int scale_uv;
 
        switch (m) {
        case IIO_CHAN_INFO_RAW:
@@ -180,10 +179,9 @@ static int ad799x_read_raw(struct iio_dev *indio_dev,
                        RES_MASK(chan->scan_type.realbits);
                return IIO_VAL_INT;
        case IIO_CHAN_INFO_SCALE:
-               scale_uv = (st->int_vref_mv * 1000) >> chan->scan_type.realbits;
-               *val =  scale_uv / 1000;
-               *val2 = (scale_uv % 1000) * 1000;
-               return IIO_VAL_INT_PLUS_MICRO;
+               *val = st->int_vref_mv;
+               *val2 = chan->scan_type.realbits;
+               return IIO_VAL_FRACTIONAL_LOG2;
        }
        return -EINVAL;
 }