mux: select demux proc function based on source buffer

[bkokoszx]

Demux should select proc func based on source buffer,
because sink can be not set yet (e.g. this can be observed
in smart amplifier topology scenario where there is
buffer between playback and capture pipeline).

Signed-off-by: Bartosz Kokoszko bartoszx.kokoszko@linux.intel.com

[akloniex]

@bkokoszx I think that it might be most beneficial and flexible, to check whether HW params were set, before deciding which buffer to take params from.
Also, similar check could be then added to mux processing function selection.

[lgirdwood]

@keyonjie will your param update fix this ?

[keyonjie]

@keyonjie will your param update fix this ?

Yes, I think so.

[lgirdwood]

@keyonjie@bkokoszx can we close this ?

[bkokoszx]

@lgirdwood
If we want to merge #2788 in future, then we can close it.

[lgirdwood]

@akloniex@bkokoszx@keyonjie@mmaka1 my understanding is that we are pending some pipeline rules being written by @mmaka1 . Any updates here ?

[mmaka1]

(de)mux is not supposed to do any conversion atm, so #2788 plus param negotiation is an extension.