snd_pcm_release_substream() always calls hw_free op when the stream
was opened.  This is superfluous in most cases because it's been
already released via explicit hw_free ioctl.  Although this double
call is usually OK as this callback should be written to be called
multiple times, it's better to avoid superfluous calls.
Reported-by: Vinod Koul <vinod.koul@intel.com>
Tested-by: Jeeja Kp <jeeja.kp@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
 
        snd_pcm_drop(substream);
        if (substream->hw_opened) {
-               if (substream->ops->hw_free != NULL)
+               if (substream->ops->hw_free &&
+                   substream->runtime->status->state != SNDRV_PCM_STATE_OPEN)
                        substream->ops->hw_free(substream);
                substream->ops->close(substream);
                substream->hw_opened = 0;