#619: Autodetection always shows one device per sound card but sometimes could
have more tha one
--------------------------+-------------------------------------------------
Reporter: howl | Owner: lennart
Type: enhancement | Status: reopened
Milestone: | Component: module-hal-detect
Resolution: | Keywords:
--------------------------+-------------------------------------------------
Comment(by lennart):
First, I doubt that driving SPDIF and analog out at the same time is
really a much needed feature. I mean, really, how many ears do you have?
4? I am pretty sure some people do want to make sure of that, but I doubt
it's a non-trivial number.
Now, the big problem here is that we cannot auto detect whether spdif and
analog are exclsuive to each other or not. Currently we try every
combinatin of input and output and if it works add it to our list of
working profiles. However, if we change this logic to also test every
combination of analog out and spdif out then we have a problem: we cannot
distuingish the case where the card supports hw mixing but only one output
at a time and where the card supports two simultaneous and independant
outputs. That means on some hardware we'd expose a profile "spdif out +
analog out" which would actuallly mix and output to one, or to both
outputs. And we certainly don't want to expose that.
So, as mentioned, the alsa enumeration API is just too simple. It does not
include information about which devices of a card can be used together and
which devices cannot.
--
Ticket URL: <http://pulseaudio.org/ticket/619#comment:14>
PulseAudio <http://pulseaudio.org/>
The PulseAudio Sound Server
_______________________________________________
pulseaudio-tickets mailing list
pulseaudio-tickets@mail.0pointer.de
https://tango.0pointer.de/mailman/listinfo/pulseaudio-tickets
