ALSA: usb-audio: Trigger PCM XRUN at XRUN
The usb-audio driver detects XRUN at its complete callback, but the
actual code to trigger PCM XRUN is commented out because it caused
deadlock in the past. This patch revives the PCM trigger properly.
It resulted in more than just enabling snd_pcm_stop(), but it had to
deduce the PCM substream with proper NULL checks and holds the stream
lock around the call.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
index 167d0c1..a467991 100644
--- a/sound/usb/endpoint.c
+++ b/sound/usb/endpoint.c
@@ -348,6 +348,8 @@
{
struct snd_urb_ctx *ctx = urb->context;
struct snd_usb_endpoint *ep = ctx->ep;
+ struct snd_pcm_substream *substream;
+ unsigned long flags;
int err;
if (unlikely(urb->status == -ENOENT || /* unlinked */
@@ -364,8 +366,6 @@
goto exit_clear;
if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
- unsigned long flags;
-
spin_lock_irqsave(&ep->lock, flags);
list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
spin_unlock_irqrestore(&ep->lock, flags);
@@ -389,7 +389,12 @@
return;
usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err);
- //snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
+ if (ep->data_subs && ep->data_subs->pcm_substream) {
+ substream = ep->data_subs->pcm_substream;
+ snd_pcm_stream_lock_irqsave(substream, flags);
+ snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
+ snd_pcm_stream_unlock_irqrestore(substream, flags);
+ }
exit_clear:
clear_bit(ctx->index, &ep->active_mask);