Re: RFC - Work on FreeBSD's Audio Stack

From: Christos Margiolis <christos_at_freebsd.org>
Date: Thu, 14 Dec 2023 23:39:33 UTC
Hello Baptiste,

Baptiste Daroussin wrote:
> Another issue which is painful with uaudio, more and more laptops have
> uaudio devices by default instead of hda, and uaudio is not able to
> suspend/resume if something is consuming it.
> 
> This is the only hotpluggable device we have for snd card, when one is
> going to suspend, the device is being detached not suspended (because
> usb) and the decatch procedure goes through the pcm_unregister
> function which loops forever hoping the application using the device
> will die, which never happens, so suspend ends up in an infinite loop
> in the kernel.
> 
> Note the same happen if you disconnect any uaudio device while an
> application is using it.

Yeap, this is what I was mostly referring to when I wrote "Other USB
audio bugs include 1) those mentioned in the snd uaudio(4) man page". 

Christos