ALSA: pcm: Don't call sync_stop if it hasn't been stopped

The PCM stop operation sets the stop_operating flag for indicating the
sync_stop post-process.  This flag is, however, set unconditionally
even if the PCM trigger weren't issued.  This may lead to
inconsistency in the driver side.

Correct the code to set stop_operating flag only after the trigger
STOP is actually called.

Fixes: 1e850beea278 ("ALSA: pcm: Add the support for sync-stop operation")
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210206203656.15959-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index cbbdb75c66ea0c882a61a647f6c878e6b5e6d820..0ae2475465ab9105761423eff4aee74bf799256b 100644 (file)
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -1421,8 +1421,10 @@ static int snd_pcm_do_stop(struct snd_pcm_substream *substream,
                           snd_pcm_state_t state)
 {
        if (substream->runtime->trigger_master == substream &&
-           snd_pcm_running(substream))
+           snd_pcm_running(substream)) {
                substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_STOP);
+               substream->runtime->stop_operating = true;
+       }
        return 0; /* unconditonally stop all substreams */
 }
 
@@ -1435,7 +1437,6 @@ static void snd_pcm_post_stop(struct snd_pcm_substream *substream,
                runtime->status->state = state;
                snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MSTOP);
        }
-       runtime->stop_operating = true;
        wake_up(&runtime->sleep);
        wake_up(&runtime->tsleep);
 }