iio:mcp4725: 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>
Cc: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/iio/dac/mcp4725.c b/drivers/iio/dac/mcp4725.c
index 7a42d85..d982752 100644 (file)
--- a/drivers/iio/dac/mcp4725.c
+++ b/drivers/iio/dac/mcp4725.c
@@ -239,17 +239,15 @@ static int mcp4725_read_raw(struct iio_dev *indio_dev,
                           int *val, int *val2, long mask)
 {
        struct mcp4725_data *data = iio_priv(indio_dev);
-       unsigned long scale_uv;
 
        switch (mask) {
        case IIO_CHAN_INFO_RAW:
                *val = data->dac_value;
                return IIO_VAL_INT;
        case IIO_CHAN_INFO_SCALE:
-               scale_uv = (data->vref_mv * 1000) >> 12;
-               *val =  scale_uv / 1000000;
-               *val2 = scale_uv % 1000000;
-               return IIO_VAL_INT_PLUS_MICRO;
+               *val = data->vref_mv;
+               *val2 = 12;
+               return IIO_VAL_FRACTIONAL_LOG2;
        }
        return -EINVAL;
 }