From mboxrd@z Thu Jan  1 00:00:00 1970
From: Vinod Koul <vinod.koul@intel.com>
Subject: Re: [PATCH v5 07/13] soundwire: Add stream
	configuration APIs
Date: Thu, 26 Apr 2018 09:58:56 +0530
Message-ID: <20180426042856.GR6014@localhost>
References: <1524649163-12088-1-git-send-email-vkoul@kernel.org>
 <1524649163-12088-8-git-send-email-vkoul@kernel.org>
 <20180426040016.GA15388@buildpc-HP-Z230>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Return-path: <alsa-devel-bounces@alsa-project.org>
Received: from mga05.intel.com (mga05.intel.com [192.55.52.43])
 by alsa0.perex.cz (Postfix) with ESMTP id 5A59826772B
 for <alsa-devel@alsa-project.org>; Thu, 26 Apr 2018 06:24:18 +0200 (CEST)
Content-Disposition: inline
In-Reply-To: <20180426040016.GA15388@buildpc-HP-Z230>
List-Unsubscribe: <http://mailman.alsa-project.org/mailman/options/alsa-devel>,
 <mailto:alsa-devel-request@alsa-project.org?subject=unsubscribe>
List-Archive: <http://mailman.alsa-project.org/pipermail/alsa-devel/>
List-Post: <mailto:alsa-devel@alsa-project.org>
List-Help: <mailto:alsa-devel-request@alsa-project.org?subject=help>
List-Subscribe: <http://mailman.alsa-project.org/mailman/listinfo/alsa-devel>,
 <mailto:alsa-devel-request@alsa-project.org?subject=subscribe>
Errors-To: alsa-devel-bounces@alsa-project.org
Sender: alsa-devel-bounces@alsa-project.org
To: Sanyog Kale <sanyog.r.kale@intel.com>
Cc: ALSA <alsa-devel@alsa-project.org>, tiwai@suse.de, Greg KH <gregkh@linuxfoundation.org>, Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>, liam.r.girdwood@linux.intel.com, patches.audio@intel.com, Vinod Koul <vkoul@kernel.org>, broonie@kernel.org
List-Id: alsa-devel@alsa-project.org

On Thu, Apr 26, 2018 at 09:30:16AM +0530, Sanyog Kale wrote:
> On Wed, Apr 25, 2018 at 03:09:17PM +0530, Vinod Koul wrote:
> > From: Sanyog Kale <sanyog.r.kale@intel.com>
> > 
> > Add APIs for prepare, enable, disable and de-prepare stream.
> > 
> > Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
> > Signed-off-by: Shreyas NC <shreyas.nc@intel.com>
> > Signed-off-by: Vinod Koul <vkoul@kernel.org>
> > ---
> >  drivers/soundwire/bus.c       |   9 ++
> >  drivers/soundwire/stream.c    | 246 ++++++++++++++++++++++++++++++++++++++++++
> >  include/linux/soundwire/sdw.h |   4 +
> >  3 files changed, 259 insertions(+)
> > 
> > +
> > +static int _sdw_deprepare_stream(struct sdw_stream_runtime *stream)
> > +{
> > +	struct sdw_master_runtime *m_rt = stream->m_rt;
> > +	struct sdw_bus *bus = m_rt->bus;
> > +	int ret = 0;
> > +
> > +	/* De-prepare port(s) */
> > +	ret = sdw_prep_deprep_ports(m_rt, false);
> > +	if (ret < 0) {
> > +		dev_err(bus->dev, "De-prepare port(s) failed: %d", ret);
> > +		return ret;
> > +	}
> > +
> > +	/* TODO: Update this during Device-Device support */
> > +	bus->params.bandwidth -= m_rt->stream->params.rate *
> > +		m_rt->ch_count * m_rt->stream->params.bps;
> > +
> 
> We should have kept zero bandwidth check here because there is no need
> to perform sdw_program_params when no stream is running on bus.

Looking at it I think it helps to program the calculated values, we may get
a new stream even before we get a chance to suspend. And frankly at bus, we
should not make any assumptions about suspend behaviour they may change with
platforms and archs :)

> 
> > +	/* Program params */
> > +	ret = sdw_program_params(bus);
> > +	if (ret < 0) {
> > +		dev_err(bus->dev, "Program params failed: %d", ret);
> > +		return ret;
> > +	}
> > +
> > +	return do_bank_switch(stream);
> 
> Change the state to DEPREPARE and then return.

good spot will fix

> 
> > +
> > +	stream->state = SDW_STREAM_DEPREPARED;
> > +
> > +	return ret;
-- 
~Vinod