diff options
-rw-r--r-- | sound/usb/pcm.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c index bf5a0f3c1fad..e5311b6bb3f6 100644 --- a/sound/usb/pcm.c +++ b/sound/usb/pcm.c @@ -845,13 +845,19 @@ get_sync_ep_from_substream(struct snd_usb_substream *subs) list_for_each_entry(fp, &subs->fmt_list, list) { ep = snd_usb_get_endpoint(chip, fp->endpoint); - if (ep && ep->cur_rate) - return ep; + if (ep && ep->cur_audiofmt) { + /* if EP is already opened solely for this substream, + * we still allow us to change the parameter; otherwise + * this substream has to follow the existing parameter + */ + if (ep->cur_audiofmt != subs->cur_audiofmt || ep->opened > 1) + return ep; + } if (!fp->implicit_fb) continue; /* for the implicit fb, check the sync ep as well */ ep = snd_usb_get_endpoint(chip, fp->sync_ep); - if (ep && ep->cur_rate) + if (ep && ep->cur_audiofmt) return ep; } return NULL; |