Re: [PATCH 3/4] iio: add helper function for reading channel offset in buffer

[Andy Shevchenko]

On Wed, Aug 17, 2022 at 1:58 PM Artur Rojek <contact@xxxxxxxxxxxxxx> wrote:
>
> This is useful for consumers that wish to parse raw buffer data.

...

> +int iio_find_channel_offset_in_buffer(struct iio_dev *indio_dev,
> +                                     const struct iio_chan_spec *chan,
> +                                     struct iio_buffer *buffer)
> +{
> +       int length, offset = 0;
> +       unsigned int si;
> +
> +       if (chan->scan_index < 0 ||
> +           !test_bit(chan->scan_index, buffer->scan_mask)) {
> +               return -EINVAL;
> +       }

Have you run checkpatch? The {} are redundant. But personally I would
split this into two separate conditionals.

> +       for (si = 0; si < chan->scan_index; ++si) {

Just a side crying: where did you, people, get this pre-increment pattern from?!

> +               if (!test_bit(si, buffer->scan_mask))
> +                       continue;

NIH for_each_set_bit()

> +               length = iio_storage_bytes_for_si(indio_dev, si);
> +
> +               /* Account for channel alignment. */
> +               if (offset % length)
> +                       offset += length - (offset % length);
> +               offset += length;
> +       }
> +
> +       return offset;
> +}
> +EXPORT_SYMBOL_GPL(iio_find_channel_offset_in_buffer);

Same Q as per previous patch: IIO namespace?

-- 
With Best Regards,
Andy Shevchenko