Re: [PATCH v3 14/27] staging: iio: resolver: ad2s1210: implement hysteresis as channel attr

David Lechner
2023-09-29T17:53:19Z

On Fri, Sep 29, 2023 at 12:25 PM David Lechner <dlechner@baylibre.com> wrote:
>
> The AD2S1210 resolver has a hysteresis feature that can be used to
> prevent flicker in the LSB of the position register. This can be either
> enabled or disabled. Disabling hysteresis is useful for increasing
> precision by oversampling.
>
> Signed-off-by: David Lechner <dlechner@baylibre.com>
> ---

...

> +static int ad2s1210_read_avail(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + const int **vals, int *type,
> + int *length, long mask)
> +{
> + static const int hysteresis_available[] = { 0, 1 };

This is basically an enable/disable. Should the 1 value be changed to the
appropriate radians value since this is hysteresis on the position
(angle) channel?

> +
> + switch (mask) {
> + case IIO_CHAN_INFO_HYSTERESIS:
> + switch (chan->type) {
> + case IIO_ANGL:
> + *vals = hysteresis_available;
> + *type = IIO_VAL_INT;
> + *length = ARRAY_SIZE(hysteresis_available);
> + return IIO_AVAIL_LIST;
> + default:
> + return -EINVAL;
> + }
> + default:
> + return -EINVAL;
> + }
> +}
>