Commit 488a2182 authored by Lars-Peter Clausen's avatar Lars-Peter Clausen Committed by Jonathan Cameron
Browse files

iio:ad7791: Report scale as fractional value 



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

Signed-off-by: default avatarLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: default avatarJonathan Cameron <jic23@kernel.org>
parent d88c89db

drivers/iio/adc/ad7791.c

+10 −8
Original line number Diff line number Diff line
@@ -202,7 +202,6 @@ static int ad7791_read_raw(struct iio_dev *indio_dev, 
{

	struct ad7791_state *st = iio_priv(indio_dev);

	bool unipolar = !!(st->mode & AD7791_MODE_UNIPOLAR);

	unsigned long long scale_pv;



	switch (info) {

	case IIO_CHAN_INFO_RAW:
@@ -220,23 +219,26 @@ static int ad7791_read_raw(struct iio_dev *indio_dev, 
	case IIO_CHAN_INFO_SCALE:

		/* The monitor channel uses an internal reference. */

		if (chan->address == AD7791_CH_AVDD_MONITOR) {

			scale_pv = 5850000000000ULL;

			/*

			 * The signal is attenuated by a factor of 5 and

			 * compared against a 1.17V internal reference.

			 */

			*val = 1170 * 5;

		} else {

			int voltage_uv;



			voltage_uv = regulator_get_voltage(st->reg);

			if (voltage_uv < 0)

				return voltage_uv;

			scale_pv = (unsigned long long)voltage_uv * 1000000;



			*val = voltage_uv / 1000;

		}

		if (unipolar)

			scale_pv >>= chan->scan_type.realbits;

			*val2 = chan->scan_type.realbits;

		else

			scale_pv >>= chan->scan_type.realbits - 1;

		*val2 = do_div(scale_pv, 1000000000);

		*val = scale_pv;

			*val2 = chan->scan_type.realbits - 1;



		return IIO_VAL_INT_PLUS_NANO;

		return IIO_VAL_FRACTIONAL_LOG2;

	}



	return -EINVAL;