From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pierre-Louis Bossart Subject: Re: [alsa-devel] [PATCH v2 3/5] ASoC: core: add support to snd_soc_dai_get_sdw_stream() Date: Tue, 13 Aug 2019 14:15:18 -0500 Message-ID: References: <20190813083550.5877-1-srinivas.kandagatla@linaro.org> <20190813083550.5877-4-srinivas.kandagatla@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Srinivas Kandagatla , vkoul@kernel.org, broonie@kernel.org Cc: devicetree@vger.kernel.org, alsa-devel@alsa-project.org, bgoswami@codeaurora.org, plai@codeaurora.org, lgirdwood@gmail.com, linux-kernel@vger.kernel.org, robh+dt@kernel.org, spapothi@codeaurora.org List-Id: devicetree@vger.kernel.org On 8/13/19 1:06 PM, Srinivas Kandagatla wrote: > > > On 13/08/2019 18:51, Pierre-Louis Bossart wrote: >> On 8/13/19 11:50 AM, Srinivas Kandagatla wrote: >>> Thanks for the review, >>> >>> On 13/08/2019 15:44, Pierre-Louis Bossart wrote: >>>> On 8/13/19 3:35 AM, Srinivas Kandagatla wrote: >>>>> On platforms which have smart speaker amplifiers connected via >>>>> soundwire and modeled as aux devices in ASoC, in such usecases machine >>>>> driver should be able to get sdw master stream from dai so that it can >>>>> use the runtime stream to setup slave streams. >>>> >>>> using the _set_sdw_stream? I don't fully get the sequence with the >>>> wording above. >>> >>> Yes, using set_sdw_stream(). >> >> Maybe I am missing something here, but I don't see where the >> set_sdw_stream() is called. > > sorry for the confusion. It was too quick reply. :-) > I was suppose to say sdw_stream_add_slave() instead of set_sdw_stream(). ok, so get_sdw_stream() and set_sdw_stream() are not meant to be mirrors or both implemented. It's just a helper to respectively get a context or set a context but a get-modify-set type of operation is not expected. Do I get this right? > > As Aux device is dailess there is no way to get hold of sdw stream > runtime for slave device associated with it. > > Having snd_soc_dai_get_sdw_stream() would help machine driver to get > hold of sdw_stream_runtime from controller dai and setup slave streams > using sdw_stream_add_slave(). > > > thanks, > srini > > >> >> Also I don't fully get the rule. set_sdw_stream() looks required, >> get_sdw_stream() is optional, is this what you are suggesting? >> >>>> >>>>> >>>>> soundwire already as a set function, get function would provide more >>>>> flexibility to above configurations. >>>> >>>> I am not clear if you are asking for both to be used, or get only or >>>> set only? >>> >>> It depends on the usecase, in db845c usecase  [1] as Aux device is >>> dai less, machine driver is using get function to get hold of master >>> stream so that it can setup slave port config. >>> >>> >>> Looks like there is a typo in above like >>> >>> This was supposed to be "soundwire already has a set function, get >>> function would provide more flexibility to above configurations" >>> >>> [1] >>> https://git.linaro.org/landing-teams/working/qualcomm/kernel.git/tree/sound/soc/qcom/db845c.c?h=integration-linux-qcomlt >>> >>> >>> thanks, >>> srini >>> >>>> >>>>> >>>>> Signed-off-by: Srinivas Kandagatla >>>>> --- >>>>>   include/sound/soc-dai.h | 10 ++++++++++ >>>>>   1 file changed, 10 insertions(+) >>>>> >>>>> diff --git a/include/sound/soc-dai.h b/include/sound/soc-dai.h >>>>> index dc48fe081a20..1e01f4a302e0 100644 >>>>> --- a/include/sound/soc-dai.h >>>>> +++ b/include/sound/soc-dai.h >>>>> @@ -202,6 +202,7 @@ struct snd_soc_dai_ops { >>>>>       int (*set_sdw_stream)(struct snd_soc_dai *dai, >>>>>               void *stream, int direction); >>>>> +    void *(*get_sdw_stream)(struct snd_soc_dai *dai, int direction); >>>>>       /* >>>>>        * DAI digital mute - optional. >>>>>        * Called by soc-core to minimise any pops. >>>>> @@ -410,4 +411,13 @@ static inline int >>>>> snd_soc_dai_set_sdw_stream(struct snd_soc_dai *dai, >>>>>           return -ENOTSUPP; >>>>>   } >>>>> +static inline void *snd_soc_dai_get_sdw_stream(struct snd_soc_dai >>>>> *dai, >>>>> +                           int direction) >>>>> +{ >>>>> +    if (dai->driver->ops->get_sdw_stream) >>>>> +        return dai->driver->ops->get_sdw_stream(dai, direction); >>>>> +    else >>>>> +        return ERR_PTR(-ENOTSUPP); >>>>> +} >>>>> + >>>>>   #endif >>>>> >>>> >>> _______________________________________________ >>> Alsa-devel mailing list >>> Alsa-devel@alsa-project.org >>> https://mailman.alsa-project.org/mailman/listinfo/alsa-devel >>