From: Takashi Iwai tiwai@suse.de
[ Upstream commit 0599313e26666e79f6e7fe1450588431b8cb25d5 ]
At the PCM hw params, we may re-configure the endpoints and it's done by a temporary EP close followed by re-open. A potential problem there is that the EP might be already running internally at the PCM prepare stage; it's seen typically in the playback stream with the implicit feedback sync. As this stream start isn't tracked by the core PCM layer, we'd need to stop it explicitly, and that's the missing piece.
This patch adds the stop_endpoints() call at snd_usb_hw_params() to assure the stream stop before closing the EPs.
Fixes: bf6313a0ff76 ("ALSA: usb-audio: Refactor endpoint management") Link: https://lore.kernel.org/r/4e509aea-e563-e592-e652-ba44af6733fe@veniogames.co... Link: https://lore.kernel.org/r/20230102170759.29610-2-tiwai@suse.de Signed-off-by: Takashi Iwai tiwai@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- sound/usb/pcm.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c index b6cd43c5ea3e..ef0c1baaefde 100644 --- a/sound/usb/pcm.c +++ b/sound/usb/pcm.c @@ -525,6 +525,8 @@ static int snd_usb_hw_params(struct snd_pcm_substream *substream, if (snd_usb_endpoint_compatible(chip, subs->data_endpoint, fmt, hw_params)) goto unlock; + if (stop_endpoints(subs, false)) + sync_pending_stops(subs); close_endpoints(chip, subs); }