linux-kernel - Re: [PATCH] ASoC: dt-bindings: wlf,wm8994: Convert to dtschema

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:   Wed, 8 Feb 2023 18:09:22 +0000
From:   Mark Brown <broonie@...nel.org>
To:     Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
Cc:     Liam Girdwood <lgirdwood@...il.com>,
        Rob Herring <robh+dt@...nel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
        - <patches@...nsource.cirrus.com>, alsa-devel@...a-project.org,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] ASoC: dt-bindings: wlf,wm8994: Convert to dtschema

On Wed, Feb 08, 2023 at 06:50:56PM +0100, Krzysztof Kozlowski wrote:
> On 08/02/2023 18:39, Mark Brown wrote:
> > On Wed, Feb 08, 2023 at 06:25:52PM +0100, Krzysztof Kozlowski wrote:

> >> 1. Add missing LDO1VDD-supply for WM1811.

> > Both LDOs are present on all variants.

> The schematics for Arndale with WM1811 and WM1811 datasheet I found in
> internet say there is only LDO1VDD pin, thus "both" does not look
> correct at least for wm1811.

> But if you meant that this should be for WM8994 as well, then sure, I
> can change it.

Ah, now I think about it IIRC LDO2 uses one of the other digital input
supplies rather than a distinct supply so there's nothing for the DT.

> >> 2. Use "gpios" suffix for wlf,ldo1ena and wlf,ldo2ena (Linux kernel's
> >>    gpiolib already looks for both variants).
> >> 3. Do not require AVDD1-supply and DCVDD-supply, because at least on
> >>    Arndale board with Exynos5250 these are grounded.

> > Are you *sure* they are grounded and not supplied from the LDOs?

> That's what I have on schematics (attached), if I got it right.

You'll notice that they've got decoupling caps on rather than being
grounded - there's an internal connection to the LDO output so if the
LDOs are in use that's all that's required, while if the LDOs are not in
use for some reason then an external supply is connected there.

Download attachment "signature.asc" of type "application/pgp-signature" (489 bytes)