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Date:   Thu, 12 Oct 2023 15:47:39 -0500
From:   Rob Herring <robh@kernel.org>
To:     Mark Brown <broonie@kernel.org>
Cc:     Chancel Liu <chancel.liu@nxp.com>, lgirdwood@gmail.com,
        krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org,
        shengjiu.wang@gmail.com, Xiubo.Lee@gmail.com, festevam@gmail.com,
        nicoleotsuka@gmail.com, perex@perex.cz, tiwai@suse.com,
        shawnguo@kernel.org, s.hauer@pengutronix.de, kernel@pengutronix.de,
        alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org,
        linuxppc-dev@lists.ozlabs.org, devicetree@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v3 1/2] ASoC: dt-bindings: sound-card-common: List DAPM
 endpoints ignoring system suspend
Message-ID: <20231012204739.GA1706264-robh@kernel.org>
References: <20231011114759.1073757-1-chancel.liu@nxp.com>
 <f639c88d-371a-4c72-a906-47d643b24ca8@sirena.org.uk>
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On Wed, Oct 11, 2023 at 10:21:33PM +0100, Mark Brown wrote:
> On Wed, Oct 11, 2023 at 07:47:58PM +0800, Chancel Liu wrote:
> 
> > +  lpa-widgets:
> > +    $ref: /schemas/types.yaml#/definitions/non-unique-string-array
> > +    description: |
> > +      A list of DAPM endpoints which mark paths between these endpoints should
> > +      not be disabled when system enters in suspend state. LPA means low power
> > +      audio case. For example on asymmetric multiprocessor, there are Cortex-A
> 
> I suspect that the DT maintainers would prefer that this description be
> workshopped a bit to remove the Linux specifics.

And Cortex A/M specifics if this is a common binding.


>  I think the key thing
> here is that these are endpoints that can be active over suspend of the
> main application processor that the current operating system is running
> (system DT stuff is an interesting corner case here...), and the example
> is probably a bit specific.  Other bindings use "audio sound widgets"
> rather than "DAPM widgets".
> 
> We also shouldn't see that these endpoints "should not be disabled"
> since that implies that they should be left on even if they aren't
> active which isn't quite the case, instead it's that we can continue
> playing an audio stream through them in suspend.

This seems like one of those things that everyone has/does, and everyone 
handles it a bit differently. I applaud trying to do something common, 
but it isn't really common until we have multiple users.

Rob