Re: [alsa-devel] [PATCH v2 3/5] ASoC: core: add support to snd_soc_dai_get_sdw_stream()

[Srinivas Kandagatla <srinivas.kandagatla@linaro.org>]

On 09/10/2019 15:29, Pierre-Louis Bossart wrote:
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> 
> On 10/9/19 3:32 AM, Srinivas Kandagatla wrote:
>> Hi Pierre,
>>
>> On 14/08/2019 15:09, Pierre-Louis Bossart wrote:
>>>
>>>
>>> On 8/13/19 11:11 PM, Vinod Koul wrote:
>>>> On 13-08-19, 20:58, Mark Brown wrote:
>>>>> On Tue, Aug 13, 2019 at 02:38:53PM -0500, Pierre-Louis Bossart wrote:
>>>>>
>>>>>> Indeed. I don't have a full understanding of that part to be 
>>>>>> honest, nor why
>>>>>> we need something SoundWire-specific. We already abused the 
>>>>>> set_tdm_slot API
>>>>>> to store an HDaudio stream, now we have a rather confusing stream
>>>>>> information for SoundWire and I have about 3 other 'stream' 
>>>>>> contexts in
>>>>>> SOF... I am still doing basic cleanups but this has been on my 
>>>>>> radar for a
>>>>>> while.
>>>>>
>>>>> There is something to be said for not abusing the TDM slot API if 
>>>>> it can
>>>>> make things clearer by using bus-idiomatic mechanisms, but it does 
>>>>> mean
>>>>> everything needs to know about each individual bus :/ .
>>>>
>>>> Here ASoC doesn't need to know about sdw bus. As Srini explained, this
>>>> helps in the case for him to get the stream context and set the stream
>>>> context from the machine driver.
>>>>
>>>> Nothing else is expected to be done from this API. We already do a set
>>>> using snd_soc_dai_set_sdw_stream(). Here we add the 
>>>> snd_soc_dai_get_sdw_stream() to query
>>>
>>> I didn't see a call to snd_soc_dai_set_sdw_stream() in Srini's code?
>>
>>
>> There is a snd_soc_dai_get_sdw_stream() to get stream context and we 
>> add slave streams(amplifier in this case) to that context using 
>> sdw_stream_add_slave() in machine driver[1].
>>
>> Without this helper there is no way to link slave streams to stream 
>> context in non dai based setup like smart speaker amplifiers.
>>
>> Currently this driver is blocked on this patch, If you think there are 
>> other ways to do this, am happy to try them out.
> 
> So to be clear, you are *not* using snd_soc_dai_set_sdw_stream?
Yes, am not using snd_soc_dai_set_sdw_stream().

--srini
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