Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20230325083643.7575-1-clamor95@gmail.com> <20230325083643.7575-2-clamor95@gmail.com>
 <20230327083208.GQ68926@ediswmail.ad.cirrus.com> <CAPVz0n1AaTzdwmfkxaUX5peAiQ2K73aoqKfLUy1jwEE6__uG2w@mail.gmail.com>
 <20230327101429.GT68926@ediswmail.ad.cirrus.com>
In-Reply-To: <20230327101429.GT68926@ediswmail.ad.cirrus.com>
From:   Svyatoslav Ryhel <clamor95@gmail.com>
Date:   Mon, 27 Mar 2023 17:48:58 +0300
Message-ID: <CAPVz0n1fOB8W43B+jfFWB_8HfBzVtn7pm_NcD-GOocaqt1MN_A@mail.gmail.com>
Subject: Re: [PATCH v1 1/1] ASoC: wm8903: implement DMIC support
To:     Charles Keepax <ckeepax@opensource.cirrus.com>
Cc:     Liam Girdwood <lgirdwood@gmail.com>,
        Mark Brown <broonie@kernel.org>,
        Jaroslav Kysela <perex@perex.cz>,
        Takashi Iwai <tiwai@suse.com>,
        Maxim Schwalm <maxim.schwalm@gmail.com>,
        Dmitry Osipenko <digetx@gmail.com>,
        patches@opensource.cirrus.com, alsa-devel@alsa-project.org,
        linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

=D0=BF=D0=BD, 27 =D0=B1=D0=B5=D1=80. 2023=E2=80=AF=D1=80. =D0=BE 13:14 Char=
les Keepax <ckeepax@opensource.cirrus.com> =D0=BF=D0=B8=D1=88=D0=B5:
>
> On Mon, Mar 27, 2023 at 11:37:05AM +0300, Svyatoslav Ryhel wrote:
> > =D0=BF=D0=BD, 27 =D0=B1=D0=B5=D1=80. 2023=E2=80=AF=D1=80. =D0=BE 11:32 =
Charles Keepax <ckeepax@opensource.cirrus.com> =D0=BF=D0=B8=D1=88=D0=B5:
> > >
> > > On Sat, Mar 25, 2023 at 10:36:43AM +0200, Svyatoslav Ryhel wrote:
> > > > Add DMIC input and routing.
> > > >
> > > > Tested-by: Svyatoslav Ryhel <clamor95@gmail.com> # ASUS TF300T
> > > > Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
> > > > ---
> > > >  sound/soc/codecs/wm8903.c | 5 ++++-
> > > >  1 file changed, 4 insertions(+), 1 deletion(-)
> > > >
> > > > diff --git a/sound/soc/codecs/wm8903.c b/sound/soc/codecs/wm8903.c
> > > > index 41346e5ec5ad..9c2f0aadcff3 100644
> > > > --- a/sound/soc/codecs/wm8903.c
> > > > +++ b/sound/soc/codecs/wm8903.c
> > > > @@ -9,7 +9,6 @@
> > > >   *
> > > >   * TODO:
> > > >   *  - TDM mode configuration.
> > > > - *  - Digital microphone support.
> > > >   */
> > > >
> > > >  #include <linux/module.h>
> > > > @@ -816,6 +815,7 @@ SND_SOC_DAPM_INPUT("IN2L"),
> > > >  SND_SOC_DAPM_INPUT("IN2R"),
> > > >  SND_SOC_DAPM_INPUT("IN3L"),
> > > >  SND_SOC_DAPM_INPUT("IN3R"),
> > > > +SND_SOC_DAPM_INPUT("DMIC"),
> > > >  SND_SOC_DAPM_INPUT("DMICDAT"),
> > >
> > > There is already a datapath for the DMIC here, DMICDAT. Are you
> > > sure you don't just need to set the "Left/Right ADC Input" muxes
> > > correctly through the ALSA controls?
> > >
> >
> > I will check once more, but so far I was not able to set the mic to
> > work with DMICDAT. Only with this patch.
> >
>
> The two should be basically equivalent when the controls are set
> right, your patch has:
>
> DMIC -> ADCL
>
> The current code has
>
> DMIC -> Left ADC Input -> ADCL
>
> The only difference is that Left ADC Input sets the ADC_DIG_MIC
> bit, but the datasheet clearly indicates that should be
> necessary for digital mics to work. Does your system definitely
> have DMICs? Without that bit set the decimator should still be
> connected to the analogue front end.
>

You are correct, this patch is not needed. It appears that the
issue was not in routing but in wm8903 gpio configuration.

DMICDAT works as intended.

> Thanks,
> Charles