Re: [alsa-devel] [RFC/PATCH v6 03/12] media: Entities, pads and links

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Clemens,

On Tuesday 14 December 2010 14:49:15 Clemens Ladisch wrote:
> Laurent Pinchart wrote:
> > On Tuesday 14 December 2010 13:40:21 Hans Verkuil wrote:
> >> > On Monday 13 December 2010 17:10:51 Clemens Ladisch wrote:
> >> >> * Entity types
> >> >> 
> >> >> TYPE_NODE was renamed to TYPE_DEVICE because "node" sounds like a
> >> >> node in a graph, which does not distinguish it from other entity
> >> >> types because all entities are part of the topology graph.  I chose
> >> >> "device" as this type describes entities that are visible as some
> >> >> device node to other software.
> >> > 
> >> > What this type describes is a device node. Both NODE and DEVICE can be
> >> > confusing in my opinion, but DEVICE_NODE is a bit long.
> >> 
> >> What about DEVNODE? I think that would be a good alternative.
> > 
> > Fine with me. Clemens, any opinion on that ?
> 
> Fine with me too.

OK I'll use that name.

> > > >> TYPE_EXT describes entities that represent some interface to the
> > > >> external world, TYPE_INT those that are internal to the entire
> > > >> device. (I'm not sure if that distinction is very useful, but
> > > >> TYPE_SUBDEV seems to be an even more meaningless name.)
> > > > 
> > > > SUBDEV comes from the V4L2 world, and I agree that it might not be a
> > > > very good name.
> > > 
> > > SUBDEV refers to a specific type of driver. Within the v4l world it is
> > > well defined. So I prefer to keep this. Perhaps some additional
> > > comments or documentation can be added to clarify this.
> > 
> > Should this be clarified by using V4L2_SUBDEV instead then ?
> 
> If the "SUBDEV" concept doesn't exist outside V4L, that would indeed be
> better.
> 
> I don't want to rename things that come out of existing frameworks; this
> naming discussion makes sense only for those entity (sub)types that can
> be shared between them.  Are there any, besides jacks?

Some entities like TV tuners play a dual audio/video role. I'm not sure how to 
handle them, I lack experience in that field.

> > What about ALSA entities, should they use MEDIA_ENTITY_TYPE_ALSA_* ?
> 
> The entity types representing ALSA devices are already named "ALSA".

I was talking about the INT_* types. They're ALSA-specific, but have no ALSA 
in the type name.

-- 
Regards,

Laurent Pinchart