Re: [PATCH v3 12/31] media: entity: Add an iterator helper for connected pads

[Sakari Ailus <sakari.ailus@linux.intel.com>]

On Thu, Mar 07, 2019 at 10:27:36AM +0000, Ian Arkver wrote:
> On 07/03/2019 10:09, Sakari Ailus wrote:
> > Hi Jacopo,
> > 
> > On Tue, Mar 05, 2019 at 07:51:31PM +0100, Jacopo Mondi wrote:
> > > From: Sakari Ailus <sakari.ailus@linux.intel.com>
> > > 
> > > Add a helper macro for iterating over pads that are connected through
> > > enabled routes. This can be used to find all the connected pads within an
> > > entity, for instance starting from the pad which has been obtained during
> > > the graph walk.
> > > 
> > > Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> > > Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > > 
> > > - Make __media_entity_next_routed_pad() return NULL and adjust the
> > >    iterator to handle that
> > > Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
> > > ---
> > >   include/media/media-entity.h | 27 +++++++++++++++++++++++++++
> > >   1 file changed, 27 insertions(+)
> > > 
> > > diff --git a/include/media/media-entity.h b/include/media/media-entity.h
> > > index 205561545d7e..82f0bdf2a6d1 100644
> > > --- a/include/media/media-entity.h
> > > +++ b/include/media/media-entity.h
> > > @@ -936,6 +936,33 @@ __must_check int media_graph_walk_init(
> > >   bool media_entity_has_route(struct media_entity *entity, unsigned int pad0,
> > >   			    unsigned int pad1);
> > > +static inline struct media_pad *__media_entity_next_routed_pad(
> > > +	struct media_pad *start, struct media_pad *iter)
> > > +{
> > > +	struct media_entity *entity = start->entity;
> > > +
> > > +	while (iter < &entity->pads[entity->num_pads] &&
> > > +	       !media_entity_has_route(entity, start->index, iter->index))
> > > +		iter++;
> > > +
> > > +	return iter == &entity->pads[entity->num_pads] ? NULL : iter;
> > 
> > Could you use iter <= ...?
> > 
> > It doesn't seem to matter here, but it'd seem safer to change the check.
> > 
> 
> How about something like...
> 
> for (; iter < &entity->pads[entity->num_pads]; iter++)
>     if (media_entity_has_route(entity, start->index, iter->index))
>         return iter;
> 
> return NULL;

Even better!

-- 
Sakari Ailus
sakari.ailus@linux.intel.com