On Thu, Jul 12, 2018 at 05:42:30PM +0200, Takashi Iwai wrote:
Pierre-Louis Bossart wrote:
On 7/11/18 3:43 AM, Srinivas Kandagatla wrote:
This patch aims at add achieving dynamic behaviour of audio card when the dependent components disappear and reappear.
Humm, no real comment on this patch proper but rather on how userspace would deal with this dynamic behavior? We had similar opens when we worked on the BYT/CHT HDMI stuff and ended-up with quite a few issues in userspace (PulseAudio mainly) related to dynamic behavior at the kernel level as a result of plug/unplug. Also not sure how an Android HAL would deal with a card disappearing temporarily if DSP resources become unavailable or unresponsive. Any thoughts or guidance you might think of?
Was the card-level register / unregister really problematic with PA? It's basically similar as the hotplug like USB, so I thought it would work as is.
Yeah, I'd expect normal desktop stuff to be able to cope with this due to physically hotpluggable hardware. The main use case for doing things like this with module unload is in a development context where hopefully people can also arrange to use a userspace that can cope or to do whatever to reset it, any limitations in some userspace shouldn't prevent people from having the facility available.