Re: RFC: V4L2 API and radio devices with multiple tuners

["Rémi Denis-Courmont" <remi@remlab.net>]

Le samedi 19 mai 2012 21:36:23 Antti Palosaari, vous avez écrit :
> On 19.05.2012 21:20, Hans de Goede wrote:
> > Currently the V4L2 API does not allow for radio devices with more then 1
> > tuner,
> > which is a bit of a historical oversight, since many radio devices have 2
> > tuners/demodulators 1 for FM and one for AM. Trying to model this as 1
> > tuner
> > really does not work well, as they have 2 completely separate frequency
> > bands
> > they handle, as well as different properties (the FM part usually is
> > stereo capable, the AM part is not).
> > 
> > It is important to realize here that usually the AM/FM tuners are part
> > of 1 chip, and often have only 1 frequency register which is used in
> > both AM/FM modes. IOW it more or less is one tuner, but with 2 modes,
> > and from a V4L2 API pov these modes are best modeled as 2 tuners.
> > This is at least true for the radio-cadet card and the tea575x,
> > which are the only 2 AM capable radio devices we currently know about.
> 
> For DVB API we changed just opposite direction - from multi-frontend to
> single-frontend. I think one device per one standard is good choice.

If I understand Hans correctly, he suggests to use two tuners on a *single* 
radio device node, much like a single video device nodes can have multiple 
video inputs. So I think you agree with Hans, and so do I.

-- 
Rémi Denis-Courmont
http://www.remlab.net/
http://fi.linkedin.com/in/remidenis