iio:ad5064: 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>

drivers/iio/dac/ad5064.c

@@ -239,10 +239,9 @@ static int ad5064_read_raw(struct iio_dev *indio_dev,
 		if (scale_uv < 0)
 			return scale_uv;
 
-		scale_uv = (scale_uv * 100) >> chan->scan_type.realbits;
-		*val =  scale_uv / 100000;
-		*val2 = (scale_uv % 100000) * 10;
-		return IIO_VAL_INT_PLUS_MICRO;
+		*val = scale_uv / 1000;
+		*val2 = chan->scan_type.realbits;
+		return IIO_VAL_FRACTIONAL_LOG2;
 	default:
 		break;
 	}