Re: [PATCH v2 3/4] iio: vcnl4000: Export near level property for proximity sensor

[Lars-Peter Clausen]

On 3/17/20 1:05 PM, Guido GÃnther wrote:
> Hi,
> On Mon, Mar 16, 2020 at 07:23:01PM +0100, Lars-Peter Clausen wrote:
> > On 3/16/20 6:46 PM, Guido GÃnther wrote:
> > > [...]
> > > +static ssize_t vcnl4000_read_near_level(struct iio_dev *indio_dev,
> > > +					uintptr_t priv,
> > > +					const struct iio_chan_spec *chan,
> > > +					char *buf)
> > > +{
> > > +	struct vcnl4000_data *data = iio_priv(indio_dev);
> > > +
> > > +	return sprintf(buf, "%u\n", data->near_level);
> > > +}
> > > +
> > > +static const struct iio_chan_spec_ext_info vcnl4000_ext_info[] = {
> > > +	{
> > > +		.name = "near_level",
> > Generally having properties with a underscore in them breaks generic parsing
> > of the property name by userspace applications. This is because we use
> > underscores to separate different components (type, modifier, etc.) of the
> > attribute from each other.
> >
> > Do you think calling this "nearlevel" would work?
> That works as well. I'll change that for v3.
>
> For my education: Is the type, modifier policy written down somewhere
> (similar to
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/leds/leds-class.rst#n44
> )?

Good point, this is quite badly documented at the moment.

The only thing I could find is this presentation by Daniel 
https://events.static.linuxfound.org/sites/events/files/slides/lceu15_baluta.pdf#page=9

- Lars