linux-kernel - Re: [PATCH] ASoC: mediatek: mt6358: support DMIC one-wire mode

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]

Message-ID: <CA+Px+wVhXoU=BdBmMW0sdPtUrnQH+Kn6dkFdW-n67qEDGceCEQ@mail.gmail.com>
Date:   Sat, 30 May 2020 01:26:20 +0800
From:   Tzung-Bi Shih <tzungbi@...gle.com>
To:     Mark Brown <broonie@...nel.org>
Cc:     Jiaxin Yu <jiaxin.yu@...iatek.com>,
        Liam Girdwood <lgirdwood@...il.com>,
        Takashi Iwai <tiwai@...e.com>,
        Matthias Brugger <matthias.bgg@...il.com>,
        Hariprasad Kelam <hariprasad.kelam@...il.com>,
        ALSA development <alsa-devel@...a-project.org>,
        linux-arm-kernel@...ts.infradead.org,
        linux-mediatek@...ts.infradead.org,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        howie.huang@...iatek.com
Subject: Re: [PATCH] ASoC: mediatek: mt6358: support DMIC one-wire mode

On Fri, May 29, 2020 at 9:05 PM Mark Brown <broonie@...nel.org> wrote:
>
> On Fri, May 29, 2020 at 07:22:43PM +0800, Tzung-Bi Shih wrote:
> > On Fri, May 29, 2020 at 7:09 PM Mark Brown <broonie@...nel.org> wrote:
>
> > > What is DMIC one wire mode?  This doesn't sound like something I'd
> > > expect to vary at runtime.
>
> > It means: 1 PDM data wire carries 2 channel data (rising edge for left
> > and falling edge for right).
>
> I thought that was normal for DMICs - is this selecting between left and
> right or something?

Not sure what is the common name but use the same context here.

MT6358 accepts up to 2 PDM wires for 2 DMICs.
If one wire mode is on, MT6358 only accepts 1 PDM wire.
If one wire mode is off, MT6358 merges L/R from 2 PDM wires into 1
I2S-like to SoC.