linux-kernel - Re: [PATCH] ASoC: tlv320aic31xx: Add MICBIAS off setting

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:   Tue, 4 Sep 2018 15:41:59 +0100
From:   Mark Brown <broonie@...nel.org>
To:     "Andrew F. Davis" <afd@...com>
Cc:     Liam Girdwood <lgirdwood@...il.com>,
        Rob Herring <robh+dt@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        alsa-devel@...a-project.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] ASoC: tlv320aic31xx: Add MICBIAS off setting

On Tue, Sep 04, 2018 at 08:55:06AM -0500, Andrew F. Davis wrote:
> On 09/03/2018 06:26 AM, Mark Brown wrote:

> > If we really want to pay attention to something setting this up we'd
> > need to completely remove the widget - what the code is doing at the
> > minute is setting the voltage that the bias will go to when enabled,
> > there's still a widget for turning it on and off.  There's some chance
> > that this will break existing boards.

> Turning on bias is controlled separately, automatically in user-space in
> many cases, not based on the board. The DT needs to have a way to state
> that 0v is the needed bias on this board, without this you can not set
> 0v bias and 2v is chosen by default (which is IMHO should be 0v but that
> would change existing behavior so I won't touch that).

Surely turning on MICBIAS at 0V is equivalent to leaving the bias off?

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