On 09/28/13 10:31, Lars-Peter Clausen wrote:
> Move the complexity of calculating the fixed point scale to the core.
>
> Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
Nice cleanup in this one.
Applied to the togreg branch of iio.git
Thanks,
> ---
> drivers/iio/adc/ad7791.c | 18 ++++++++++--------
> 1 file changed, 10 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/iio/adc/ad7791.c b/drivers/iio/adc/ad7791.c
> index c202035..c19f8fd 100644
> --- a/drivers/iio/adc/ad7791.c
> +++ b/drivers/iio/adc/ad7791.c
> @@ -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;
>
--
To unsubscribe from this list: send the line "unsubscribe linux-iio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
