[alsa-devel] unload Audio drivers while playback stream is active case kernel crash

[Fabio Estevam]

On Wed, Jan 14, 2015 at 10:57 AM, Lars-Peter Clausen <lars at metafoo.de> wrote:

> My personal opinion on this is that disallowing module removal while a
> driver registered by the module when is in use, while there is no technical
> reason to do so, is a anti-feature. Whether in ALSA or elsewhere.
>
> But looking at the source it seems that this is a core feature of ALSA and
> at least for the card module itself it will do the ref-counting when a
> stream is started/stopped. And we even support setting the owner of a card
> in ASoC. It's just that pretty much no ASoC card driver bothers to set the
> owner field in the snd_soc_card struct. So this particular problem can be
> fixed by updating the imx-wm8962 driver to set the owner field.

Thanks, Lars_Peter. This fixes the issue:

root at freescale /$ modprobe -r snd_soc_imx_wm8962
modprobe: can't unload module snd_soc_imx_wm8962: Resource temporarily
unavailable

Will send a patch with your suggestion soon.