On Tue May 22 2012 22:45:44 Hans de Goede wrote: > Hi, > > On 05/22/2012 06:26 PM, Rémi Denis-Courmont wrote: > > 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. > > Correct, although the plan has changed in the mean time to model the 1 tuner > as 1 tuner, and extend the v4l2 tuner API to deal with a tuner which can > tune multiple bands. Which seems the best way forward :) FYI: the ADS Cadet board is also tea5757 based (no surprise there). I've put up a picture of the board here: http://hverkuil.home.xs4all.nl/ADS%20Cadet%20RDX-1187.jpg Regards, Hans -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
