[alsa-devel] [PATCH 1/2] ASoC: core: call snd_soc_unregister_card() when component cleanup

[Kuninori Morimoto]

Hi Mark, again

> > ...this doesn't look like the right fix.  If we just plain unregister
> > the card then if the component that was removed is loaded again then the
> > card won't be reinstantiated since the core has forgotten about the
> > card.  Further, if the card driver is removed then we'll get a duplicate
> > attempt to unregister it which doesn't seem clever.
> > 
> > What we need to do here is undo all the work that was done to
> > instantiate the card but not actually unregister it, returning
> > everything to the state it was in before the card was instantiated.
> > That's obviously a much more substantial change than this but it's
> > what's needed (and is the main reason this is broken at the minute).

Hmm...

In normal ASoC card, it will re-try .probe if necessary cpu/codec was not probed
(= -EPROBE_DEFER in soc_bind_dai_link()).
This is the before state of card was instantiated.
Returning everything to the before state = unregister card is very natural I think...
If possible, we want to add this card driver to deferred_probe_pending_list
in drivers/base/dd.c, but it is over kill ?

Best regards
---
Kuninori Morimoto