On Sat, Aug 26, 2023 at 4:28 AM Jaroslav Kysela perex@perex.cz wrote:
On 24. 08. 23 23:33, cujomalainey@chromium.org wrote:
From: Curtis Malainey cujomalainey@chromium.org
Sometimes userspace may want to use a reference channel to cancel echos when using video chat, this value identifies the device which carries that channel.
The UCM modifier should be used for this - see "Echo Reference" comments in use-case.h.
Note that this allows additional setup (in Sequences) for this stream.
Jaroslav
I was under the impression modifiers were state manipulators that acted upon existing devices/pcms and did not designate their own PCM. That is at least how we use them in CRAS.
Are there any examples of how to designate a PCM? I don't see any modifiers at all in ucm-conf repo.
Curtis
-- Jaroslav Kysela perex@perex.cz Linux Sound Maintainer; ALSA Project; Red Hat, Inc.