From mboxrd@z Thu Jan 1 00:00:00 1970 From: Liam Girdwood Subject: Re: [PATCH] ALSA: compress: Make sure we trigger STOP before closing the stream. Date: Mon, 23 Sep 2013 11:19:39 +0100 Message-ID: <1379931579.2516.48.camel@loki> References: <1379090597-7096-1-git-send-email-liam.r.girdwood@linux.intel.com> <20130916035753.GJ17188@intel.com> <1379329283.3215.34.camel@loki> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by alsa0.perex.cz (Postfix) with ESMTP id 7221B260845 for ; Mon, 23 Sep 2013 12:20:10 +0200 (CEST) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Takashi Iwai , Vinod Koul Cc: alsa-devel@alsa-project.org, Liam Girdwood , Mark Brown List-Id: alsa-devel@alsa-project.org On Thu, 2013-09-19 at 18:43 +0200, Takashi Iwai wrote: > At Mon, 16 Sep 2013 12:01:23 +0100, > Liam Girdwood wrote: > > > > On Mon, 2013-09-16 at 09:27 +0530, Vinod Koul wrote: > > > On Fri, Sep 13, 2013 at 05:43:16PM +0100, Liam Girdwood wrote: > > > > Currently we assume that userspace will shut down the compressed stream > > > > correctly. However, if userspcae dies (e.g. cplay & ctrl-C) we dont > > > > stop the stream before freeing it. > > > > > > > > This now checks that the stream is stopped before freeing. > > > > > > > > Signed-off-by: Liam Girdwood > > > > --- > > > > sound/core/compress_offload.c | 12 ++++++++++++ > > > > 1 file changed, 12 insertions(+) > > > > > > > > diff --git a/sound/core/compress_offload.c b/sound/core/compress_offload.c > > > > index 99db892..a9ae4f3 100644 > > > > --- a/sound/core/compress_offload.c > > > > +++ b/sound/core/compress_offload.c > > > > @@ -139,6 +139,18 @@ static int snd_compr_open(struct inode *inode, struct file *f) > > > > static int snd_compr_free(struct inode *inode, struct file *f) > > > > { > > > > struct snd_compr_file *data = f->private_data; > > > > + struct snd_compr_runtime *runtime = data->stream.runtime; > > > > + > > > > + switch (runtime->state) { > > > > + case SNDRV_PCM_STATE_RUNNING: > > > > + case SNDRV_PCM_STATE_DRAINING: > > > > + case SNDRV_PCM_STATE_PAUSED: > > > > + data->stream.ops->trigger(&data->stream, SNDRV_PCM_TRIGGER_STOP); > > > when usermode dies the free will get invoked as we have below. The free is a > > > valid trigger from any state. So shouldnt the DSP then STOP the DMAs and free > > > the streams. > > > > This means that the compressed stream ops don't follow the PCM ops wrt > > trigger() sequencing (i.e. we have to add extra logic in free to deal > > with this difference). > > > > I think it would be better to follow the PCM operations use case here as > > it simplifies the driver code and stops people making the false > > assumption that trigger() works the same way throughout ALSA ? > > Well, the trigger of compress API has a few more jobs than PCM, > and it's exactly what should be fixed (e.g. the proper handling of > drain). We need a bit more consensus over that. > > So, I didn't apply this patch yet. If Vinod is happy with this (even > as a temporary solution), let me know. Without this patch we have the two different sequences for shutdown depending on whether userspace dies or not. i.e. 1) Normal: trigger(start) -> play -> trigger(stop) -> close() 2) ctrl-C: trigger(start) -> play -> ctrl-C -> close() So we miss out the trigger(STOP) and close the device with the stream still in a trigger running state. Liam