linux-kernel - Re: [PATCH v3 1/2] ASoC: dt-bindings: sound-card-common: List DAPM endpoints ignoring system suspend

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20231012204739.GA1706264-robh@kernel.org>
Date:   Thu, 12 Oct 2023 15:47:39 -0500
From:   Rob Herring <robh@...nel.org>
To:     Mark Brown <broonie@...nel.org>
Cc:     Chancel Liu <chancel.liu@....com>, lgirdwood@...il.com,
        krzysztof.kozlowski+dt@...aro.org, conor+dt@...nel.org,
        shengjiu.wang@...il.com, Xiubo.Lee@...il.com, festevam@...il.com,
        nicoleotsuka@...il.com, perex@...ex.cz, tiwai@...e.com,
        shawnguo@...nel.org, s.hauer@...gutronix.de, kernel@...gutronix.de,
        alsa-devel@...a-project.org, linux-kernel@...r.kernel.org,
        linuxppc-dev@...ts.ozlabs.org, devicetree@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH v3 1/2] ASoC: dt-bindings: sound-card-common: List DAPM
 endpoints ignoring system suspend

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