On 31. 12. 22 12:38, Ruud van Asseldonk wrote:
Hi all,
I bisected this and identified e4ea77f8e53f9accb9371fba34c189d0447ecce0
(ALSA: usb-audio: Always apply the hw constraints for implicit fb sync)
as the first commit where it is no longer possible to change the sample
rate. On the parent commit, my sample program successfully changes the
sample rate from 44100 Hz to 96000 Hz, but on e4ea77f8e53f9, the second
call to snd_pcm_hw_params fails.
There is an easy workaround - call snd_pcm_hw_free() between the params setup.
This call ensure that the sync ep is freed. I can just confirm that this
problem is only for USB hw with the implicit feedback (tested with 6.0.11 kernel).
I will try to debug this when I find a little free time. Perhaps, Takashi may
have a straight idea, what's wrong. When only one stream is used, this
hw_params call should succeed, too.
Jaroslav
--
Jaroslav Kysela <perex@xxxxxxxx>
Linux Sound Maintainer; ALSA Project; Red Hat, Inc.
