[PATCH] ALSA: usb-audio: Split endpoint setups for hw_params and prepare (take#2)

[Takashi Iwai]

On Mon, 03 Oct 2022 17:27:37 +0200,
Geoffrey D. Bennett wrote:
> 
> Hi Takashi,
> 
> On Tue, Sep 20, 2022 at 08:11:06PM +0200, Takashi Iwai wrote:
> > This is a second attempt to fix the bug appearing on Android with the
> > recent kernel; the first try was ff878b408a03 and reverted at commit
> > 79764ec772bc.
> 
> I found that full-duplex audio for Scarlett devices was broken in
> 5.19.11 but working again 5.19.12, presumably due to this. escuta at
> https://linuxmusicians.com/viewtopic.php?p=148734#p148734 reported
> that it was broken from 5.19.9 but 5.19.8 worked (they also reported
> that 5.9.12 didn't work, which I can't explain).
> 
> 5.19.12 and 6.0.0 work for me, but 6.0.0 + your v2 patch makes the
> gnome sound settings app crash when setting the output device to
> Scarlett if the input device was already set to Scarlett.
> 
> Using the gnome-control-center (42.3) app (Fedora 36, PipeWire 0.3.59,
> WirePlumber 0.4.11) to test:
> 
> - Kernel 5.19.11: can't set both input and output device to Scarlett;
>   changing output to Scarlett makes the input device switch to
>   something else, and changing the input device to Scarlett makes the
>   output device switch to something else
> 
> - Kernel 5.9.12 & 6.0.0: can set both input and output device to
>   Scarlett, all good/normal
> 
> - Kernel 6.0.0+v2 patch: if both input and output device are already
>   set to Scarlett, works fine. Change output device to something else
>   then back to Scarlett, the settings app hangs. Kill the app, restart
>   it, the input & output device are both Scarlett & it appears to work
>   fine again until you change the output device to Scarlett when the
>   input device is already Scarlett. Changing it in the other order
>   (set input device to Scarlett when output device is already
>   Scarlett) works no problem.

Hmm.  Just to be sure, could you verify the behavior with 6.0 +
for-linus branch of sound git repo?


thanks,

Takashi