Re: [PATCH 2/2] ASoC: qcom: Move Soundwire runtime stream alloc to soundcards

From: Krzysztof Kozlowski
Date: Tue Nov 28 2023 - 11:59:22 EST


On 28/11/2023 17:56, Krzysztof Kozlowski wrote:
> Currently the Qualcomm Soundwire controller in its DAI startup op
> allocates the Soundwire stream runtime. This works fine for existing
> designs, but has limitations for stream runtimes with multiple
> controllers, like upcoming Qualcomm X1E80100 SoC with four WSA8840
> speakers on two Soundwire controllers.
>
> When two Soundwire controllers are added to sound card codecs, Soundwire
> startup() is called twice, one for each Soundwire controller, and second
> execution overwrites what was set before. During shutdown() this causes
> double free.
>
> It is expected to have only one Soundwire stream runtime, thus it should
> be allocated from SoC soundcard context startup(), not from each
> Soundwire startup(). Such way will properly handle both cases: one and
> two Soundwire controllers in the stream runtime.
>
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
>
> ---
>
> This is an entirely different approach than my previous try here:
> https://lore.kernel.org/all/20231025144601.268645-1-krzysztof.kozlowski@xxxxxxxxxx/

... and I forgot to thank you Pierre-Louis for patient explanation of
the case in my previous try. Your review was much appreciated!

Thank you.

Best regards,
Krzysztof