Re: [PATCH 02/10] iio: core: Enhance the kernel doc of modes and currentmodes iio_dev entries

[Jonathan Cameron <jic23@kernel.org>]

On Thu, 16 Dec 2021 09:15:52 +0100
Miquel Raynal <miquel.raynal@bootlin.com> wrote:

> Hi Alexandru,
> 
> ardeleanalex@gmail.com wrote on Thu, 16 Dec 2021 08:24:51 +0200:
> 
> > On Wed, Dec 15, 2021 at 10:04 PM Miquel Raynal
> > <miquel.raynal@bootlin.com> wrote:  
> > >
> > > Let's provide more details about these two variables because their
> > > understanding may not be straightforward for someone not used to the IIO
> > > subsystem internal logic. The different modes will soon be also be more
> > > documented for the same reason.
> > >
> > > Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
> > > ---
> > >  include/linux/iio/iio.h | 10 ++++++++--
> > >  1 file changed, 8 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
> > > index 06433c2c2968..0312da2e83f8 100644
> > > --- a/include/linux/iio/iio.h
> > > +++ b/include/linux/iio/iio.h
> > > @@ -487,8 +487,14 @@ struct iio_buffer_setup_ops {
> > >
> > >  /**
> > >   * struct iio_dev - industrial I/O device
> > > - * @modes:             [DRIVER] operating modes supported by device
> > > - * @currentmode:       [INTERN] current operating mode
> > > + * @modes:             [DRIVER] list of operating modes supported by the IIO    
> > 
> > I'd argue that it may make sense to highlight that this list of modes
> > is represented as a bitmask.
> > When reading docs, it may not be obvious at first (I guess).  
> 
> That is a good idea. I'll add this to the next iteration.

Good.

> 
> > > + *                     device, this list should be initialized before
> > > + *                     registering the IIO device and can be filed up by the
> > > + *                     IIO core depending on the features advertised by the
> > > + *                     driver during other steps of the registration

Perhaps make it a little clearer that some bits are set as a result of
enabling particular features.  Maybe even call out which functions do it.
From what I recall, that's a very short list.

> > > + * @currentmode:       [INTERN] operating mode currently in use, may be
> > > + *                     eventually checked by device drivers but should be
> > > + *                     considered read-only as this is a core internal bit

We should add an accessor function to read it.  (maybe later in your series? :)

> > >   * @dev:               [DRIVER] device structure, should be assigned a parent
> > >   *                     and owner
> > >   * @buffer:            [DRIVER] any buffer present
> > > --
> > > 2.27.0
> > >    
> 
> Thanks,
> Miquèl