Re: [PATCH v2] iio: potentiometer: add driver for Maxim Integrated DS1803

[Slawomir Stepien]

On Apr 08, 2016 23:27, Slawomir Stepien wrote:
> +static int ds1803_read_raw(struct iio_dev *indio_dev,
> +                         struct iio_chan_spec const *chan,
> +                         int *val, int *val2, long mask)
> +{
> +     struct ds1803_data *data = iio_priv(indio_dev);
> +     int pot = chan->channel;
> +     int ret;
> +     u16 result;
> +
> +     switch (mask) {
> +     case IIO_CHAN_INFO_RAW:
> +             ret = i2c_master_recv(data->client, (char *)&result,
> +                             indio_dev->num_channels);
> +             if (ret < 0)
> +                     return ret;
> +
> +             /* Get bits for given pot */
> +             *val = (pot == 0 ? result & 0xff : result >> 8);
> +             return IIO_VAL_INT;
> +
> +     case IIO_CHAN_INFO_SCALE:
> +             *val = 1000 * data->cfg->kohms;
> +             *val2 = DS1803_MAX_POS;
> +             return IIO_VAL_FRACTIONAL;
> +     }
> +
> +     return -EINVAL;
> +}

Or maybe this is more clean?

static int ds1803_read_raw(struct iio_dev *indio_dev,
                            struct iio_chan_spec const *chan,
                            int *val, int *val2, long mask)
{
        struct ds1803_data *data = iio_priv(indio_dev);
        int pot = chan->channel;
        int ret;
        unsigned char result[indio_dev->num_channels];

        switch (mask) {
        case IIO_CHAN_INFO_RAW:
                ret = i2c_master_recv(data->client, result,
                                indio_dev->num_channels);
                if (ret < 0)
                        return ret;

                *val = result[pot];
                return IIO_VAL_INT;

        case IIO_CHAN_INFO_SCALE:
                *val = 1000 * data->cfg->kohms;
                *val2 = DS1803_MAX_POS;
                return IIO_VAL_FRACTIONAL;
        }

        return -EINVAL;
}

What do you think?

-- 
Slawomir Stepien