ALSA: usb-audio: Disable low-latency mode for implicit feedback sync
authorTakashi Iwai <tiwai@suse.de>
Wed, 29 Sep 2021 08:08:40 +0000 (10:08 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 8 Dec 2021 08:04:36 +0000 (09:04 +0100)
commit8d7c6f515b1529fde3496c0753c088207b2a457b
tree58d83bd42bdd2b8453a6fa33b9a3efd732ce0713
parent5ca1fa52d351256f3378593bcc53b995b855a46d
ALSA: usb-audio: Disable low-latency mode for implicit feedback sync

commit bceee75387554f682638e719d1ea60125ea78cea upstream.

When a playback stream runs in the implicit feedback mode, its
operation is passive and won't start unless the capture packet is
received.  This behavior contradicts with the low-latency playback
mode, and we should turn off lowlatency_playback flag accordingly.

In theory, we may take the low-latency mode when the playback-first
quirk is set, but it still conflicts with the later operation with the
fixed packet numbers, so it's disabled all together for now.

Link: https://lore.kernel.org/r/20210929080844.11583-6-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sound/usb/pcm.c