by Clément Péron

[permalink] [raw]

Subject: Re: [PATCH v4 09/22] arm64: dts: allwinner: h6: Add HDMI audio node

Hi Maxime,

On Mon, 21 Sep 2020 at 15:59, Maxime Ripard <[email protected]> wrote:
>
> On Mon, Sep 21, 2020 at 12:27:18PM +0200, Clément Péron wrote:
> > From: Jernej Skrabec <[email protected]>
> >
> > Add a simple-soundcard to link audio between HDMI and I2S.
> >
> > Signed-off-by: Jernej Skrabec <[email protected]>
> > Signed-off-by: Marcus Cooper <[email protected]>
> > Signed-off-by: Clément Péron <[email protected]>
> > ---
> > arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi | 33 ++++++++++++++++++++
> > 1 file changed, 33 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > index 28c77d6872f6..a8853ee7885a 100644
> > --- a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > +++ b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > @@ -67,6 +67,25 @@ de: display-engine {
> > status = "disabled";
> > };
> >
> > + hdmi_sound: hdmi-sound {
> > + compatible = "simple-audio-card";
> > + simple-audio-card,format = "i2s";
> > + simple-audio-card,name = "sun50i-h6-hdmi";
> > + simple-audio-card,mclk-fs = <128>;
> > + simple-audio-card,frame-inversion;
> > + status = "disabled";
> > +
> > + simple-audio-card,codec {
> > + sound-dai = <&hdmi>;
> > + };
> > +
> > + simple-audio-card,cpu {
> > + sound-dai = <&i2s1>;
> > + dai-tdm-slot-num = <2>;
> > + dai-tdm-slot-width = <32>;
>
> It looks weird to have both some TDM setup here, and yet the format in
> i2s?

Yes, I agree I will check if it's really needed.

Clement

>
> Maxime

2020-09-21 18:28:07

by Mark Brown

[permalink] [raw]

Subject: Re: [PATCH v4 02/22] ASoC: sun4i-i2s: Change set_chan_cfg() params

On Mon, Sep 21, 2020 at 07:15:13PM +0200, Cl?ment P?ron wrote:
> On Mon, 21 Sep 2020 at 14:29, Maxime Ripard <[email protected]> wrote:

> > Also, Fixes tag?

> I think this only happens when 20/24bit is enabled so the issue has been
> introduced in this series.

For a situation like that a note in the changelog about "in preparation
for adding X support which will make this matter" helps.

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2020-09-21 18:32:49

On Mon, Sep 21, 2020 at 08:37:09PM +0200, Jernej Škrabec wrote:
> Dne ponedeljek, 21. september 2020 ob 19:23:49 CEST je Clément Péron
> napisal(a):
> > Hi Maxime,
> >
> > On Mon, 21 Sep 2020 at 15:59, Maxime Ripard <[email protected]> wrote:
> > >
> > > On Mon, Sep 21, 2020 at 12:27:18PM +0200, Clément Péron wrote:
> > > > From: Jernej Skrabec <[email protected]>
> > > >
> > > > Add a simple-soundcard to link audio between HDMI and I2S.
> > > >
> > > > Signed-off-by: Jernej Skrabec <[email protected]>
> > > > Signed-off-by: Marcus Cooper <[email protected]>
> > > > Signed-off-by: Clément Péron <[email protected]>
> > > > ---
> > > > arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi | 33 ++++++++++++++++++++
> > > > 1 file changed, 33 insertions(+)
> > > >
> > > > diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi b/arch/arm64/
> boot/dts/allwinner/sun50i-h6.dtsi
> > > > index 28c77d6872f6..a8853ee7885a 100644
> > > > --- a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > > +++ b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > > @@ -67,6 +67,25 @@ de: display-engine {
> > > > status = "disabled";
> > > > };
> > > >
> > > > + hdmi_sound: hdmi-sound {
> > > > + compatible = "simple-audio-card";
> > > > + simple-audio-card,format = "i2s";
> > > > + simple-audio-card,name = "sun50i-h6-hdmi";
> > > > + simple-audio-card,mclk-fs = <128>;
> > > > + simple-audio-card,frame-inversion;
> > > > + status = "disabled";
> > > > +
> > > > + simple-audio-card,codec {
> > > > + sound-dai = <&hdmi>;
> > > > + };
> > > > +
> > > > + simple-audio-card,cpu {
> > > > + sound-dai = <&i2s1>;
> > > > + dai-tdm-slot-num = <2>;
> > > > + dai-tdm-slot-width = <32>;
> > >
> > > It looks weird to have both some TDM setup here, and yet the format in
> > > i2s?
> >
> > Yes, I agree I will check if it's really needed.
>
> I think this was explained before.

Possibly, but this should be in a comment or at least the commit log

> Anyway, this is needed to force width to 32, no matter actual sample
> width. That's a requirement of HDMI codec. I believe Marcus Cooper
> have another codec which also needs fixed width.
>
> There is no similar property for I2S, so TDM one is used here.

Except it's really dedicated to the TDM mode and doesn't really make
much sense here.

If we have special requirements like this on the codec setup, that
sounds like a good justification for creating a custom codec instead of
shoehorning it into simple-card

Maxime

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2020-09-28 08:57:29

On Mon, Sep 28, 2020 at 04:27:42PM +0200, Clément Péron wrote:
> On Mon, 28 Sep 2020 at 10:43, Maxime Ripard <[email protected]> wrote:
> >
> > On Mon, Sep 21, 2020 at 08:37:09PM +0200, Jernej Škrabec wrote:
> > > Dne ponedeljek, 21. september 2020 ob 19:23:49 CEST je Clément Péron
> > > napisal(a):
> > > > Hi Maxime,
> > > >
> > > > On Mon, 21 Sep 2020 at 15:59, Maxime Ripard <[email protected]> wrote:
> > > > >
> > > > > On Mon, Sep 21, 2020 at 12:27:18PM +0200, Clément Péron wrote:
> > > > > > From: Jernej Skrabec <[email protected]>
> > > > > >
> > > > > > Add a simple-soundcard to link audio between HDMI and I2S.
> > > > > >
> > > > > > Signed-off-by: Jernej Skrabec <[email protected]>
> > > > > > Signed-off-by: Marcus Cooper <[email protected]>
> > > > > > Signed-off-by: Clément Péron <[email protected]>
> > > > > > ---
> > > > > > arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi | 33 ++++++++++++++++++++
> > > > > > 1 file changed, 33 insertions(+)
> > > > > >
> > > > > > diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi b/arch/arm64/
> > > boot/dts/allwinner/sun50i-h6.dtsi
> > > > > > index 28c77d6872f6..a8853ee7885a 100644
> > > > > > --- a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > > > > +++ b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > > > > @@ -67,6 +67,25 @@ de: display-engine {
> > > > > > status = "disabled";
> > > > > > };
> > > > > >
> > > > > > + hdmi_sound: hdmi-sound {
> > > > > > + compatible = "simple-audio-card";
> > > > > > + simple-audio-card,format = "i2s";
> > > > > > + simple-audio-card,name = "sun50i-h6-hdmi";
> > > > > > + simple-audio-card,mclk-fs = <128>;
> > > > > > + simple-audio-card,frame-inversion;
> > > > > > + status = "disabled";
> > > > > > +
> > > > > > + simple-audio-card,codec {
> > > > > > + sound-dai = <&hdmi>;
> > > > > > + };
> > > > > > +
> > > > > > + simple-audio-card,cpu {
> > > > > > + sound-dai = <&i2s1>;
> > > > > > + dai-tdm-slot-num = <2>;
> > > > > > + dai-tdm-slot-width = <32>;
> > > > >
> > > > > It looks weird to have both some TDM setup here, and yet the format in
> > > > > i2s?
> > > >
> > > > Yes, I agree I will check if it's really needed.
> > >
> > > I think this was explained before.
> >
> > Possibly, but this should be in a comment or at least the commit log
> >
> > > Anyway, this is needed to force width to 32, no matter actual sample
> > > width. That's a requirement of HDMI codec. I believe Marcus Cooper
> > > have another codec which also needs fixed width.
> > >
> > > There is no similar property for I2S, so TDM one is used here.
> >
> > Except it's really dedicated to the TDM mode and doesn't really make
> > much sense here.
> >
> > If we have special requirements like this on the codec setup, that
> > sounds like a good justification for creating a custom codec instead of
> > shoehorning it into simple-card
>
> When all the remarks are fixed would it be possible to merge the rest
> of the series without the dts changes ?
>
> I will propose another series to introduce a dedicated codec for that.

Yeah, sure

Maxime

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2020-11-01 15:30:03

by Clément Péron

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Subject: Re: [PATCH v4 09/22] arm64: dts: allwinner: h6: Add HDMI audio node

Hi Maxime,

On Wed, 30 Sep 2020 at 12:19, Maxime Ripard <[email protected]> wrote:
>
> On Mon, Sep 28, 2020 at 04:27:42PM +0200, Clément Péron wrote:
> > On Mon, 28 Sep 2020 at 10:43, Maxime Ripard <[email protected]> wrote:
> > >
> > > On Mon, Sep 21, 2020 at 08:37:09PM +0200, Jernej Škrabec wrote:
> > > > Dne ponedeljek, 21. september 2020 ob 19:23:49 CEST je Clément Péron
> > > > napisal(a):
> > > > > Hi Maxime,
> > > > >
> > > > > On Mon, 21 Sep 2020 at 15:59, Maxime Ripard <[email protected]> wrote:
> > > > > >
> > > > > > On Mon, Sep 21, 2020 at 12:27:18PM +0200, Clément Péron wrote:
> > > > > > > From: Jernej Skrabec <[email protected]>
> > > > > > >
> > > > > > > Add a simple-soundcard to link audio between HDMI and I2S.
> > > > > > >
> > > > > > > Signed-off-by: Jernej Skrabec <[email protected]>
> > > > > > > Signed-off-by: Marcus Cooper <[email protected]>
> > > > > > > Signed-off-by: Clément Péron <[email protected]>
> > > > > > > ---
> > > > > > > arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi | 33 ++++++++++++++++++++
> > > > > > > 1 file changed, 33 insertions(+)
> > > > > > >
> > > > > > > diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi b/arch/arm64/
> > > > boot/dts/allwinner/sun50i-h6.dtsi
> > > > > > > index 28c77d6872f6..a8853ee7885a 100644
> > > > > > > --- a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > > > > > +++ b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > > > > > @@ -67,6 +67,25 @@ de: display-engine {
> > > > > > > status = "disabled";
> > > > > > > };
> > > > > > >
> > > > > > > + hdmi_sound: hdmi-sound {
> > > > > > > + compatible = "simple-audio-card";
> > > > > > > + simple-audio-card,format = "i2s";
> > > > > > > + simple-audio-card,name = "sun50i-h6-hdmi";
> > > > > > > + simple-audio-card,mclk-fs = <128>;
> > > > > > > + simple-audio-card,frame-inversion;
> > > > > > > + status = "disabled";
> > > > > > > +
> > > > > > > + simple-audio-card,codec {
> > > > > > > + sound-dai = <&hdmi>;
> > > > > > > + };
> > > > > > > +
> > > > > > > + simple-audio-card,cpu {
> > > > > > > + sound-dai = <&i2s1>;
> > > > > > > + dai-tdm-slot-num = <2>;
> > > > > > > + dai-tdm-slot-width = <32>;
> > > > > >
> > > > > > It looks weird to have both some TDM setup here, and yet the format in
> > > > > > i2s?

I was looking at sound documentation regarding how I can properly
write the multi-lane I2S support.
And I think we made a wrong interpretation here.

TDM slot-num and slot-width are not referencing the format called PCM
or DSP_A / DSP_B.
But really the physical time division representation of a format.

For example Amlogic do the following representation for Multi-lane I2S:

dai-link-7 {
sound-dai = <&tdmif_b>;
dai-format = "i2s";
dai-tdm-slot-tx-mask-0 = <1 1>;
dai-tdm-slot-tx-mask-1 = <1 1>;
dai-tdm-slot-tx-mask-2 = <1 1>;
dai-tdm-slot-tx-mask-3 = <1 1>;
mclk-fs = <256>;

codec {
sound-dai = <&tohdmitx TOHDMITX_I2S_IN_B>;
};
};

So i think for 2 channels HDMI using the simple sound card with TDM
property is not a hack but the correct way to represent it.

Do you agree ?

If so, can I resend the simple sound card for HDMI audio ?

Thanks,
Clement

> > > > >
> > > > > Yes, I agree I will check if it's really needed.
> > > >
> > > > I think this was explained before.
> > >
> > > Possibly, but this should be in a comment or at least the commit log
> > >
> > > > Anyway, this is needed to force width to 32, no matter actual sample
> > > > width. That's a requirement of HDMI codec. I believe Marcus Cooper
> > > > have another codec which also needs fixed width.
> > > >
> > > > There is no similar property for I2S, so TDM one is used here.
> > >
> > > Except it's really dedicated to the TDM mode and doesn't really make
> > > much sense here.
> > >
> > > If we have special requirements like this on the codec setup, that
> > > sounds like a good justification for creating a custom codec instead of
> > > shoehorning it into simple-card
> >
> > When all the remarks are fixed would it be possible to merge the rest
> > of the series without the dts changes ?
> >
> > I will propose another series to introduce a dedicated codec for that.
>
> Yeah, sure
>
> Maxime

2020-11-02 10:23:08

by Maxime Ripard

[permalink] [raw]

Subject: Re: [PATCH v4 09/22] arm64: dts: allwinner: h6: Add HDMI audio node

On Sun, Nov 01, 2020 at 04:27:05PM +0100, Clément Péron wrote:
> On Wed, 30 Sep 2020 at 12:19, Maxime Ripard <[email protected]> wrote:
> >
> > On Mon, Sep 28, 2020 at 04:27:42PM +0200, Clément Péron wrote:
> > > On Mon, 28 Sep 2020 at 10:43, Maxime Ripard <[email protected]> wrote:
> > > >
> > > > On Mon, Sep 21, 2020 at 08:37:09PM +0200, Jernej Škrabec wrote:
> > > > > Dne ponedeljek, 21. september 2020 ob 19:23:49 CEST je Clément Péron
> > > > > napisal(a):
> > > > > > Hi Maxime,
> > > > > >
> > > > > > On Mon, 21 Sep 2020 at 15:59, Maxime Ripard <[email protected]> wrote:
> > > > > > >
> > > > > > > On Mon, Sep 21, 2020 at 12:27:18PM +0200, Clément Péron wrote:
> > > > > > > > From: Jernej Skrabec <[email protected]>
> > > > > > > >
> > > > > > > > Add a simple-soundcard to link audio between HDMI and I2S.
> > > > > > > >
> > > > > > > > Signed-off-by: Jernej Skrabec <[email protected]>
> > > > > > > > Signed-off-by: Marcus Cooper <[email protected]>
> > > > > > > > Signed-off-by: Clément Péron <[email protected]>
> > > > > > > > ---
> > > > > > > > arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi | 33 ++++++++++++++++++++
> > > > > > > > 1 file changed, 33 insertions(+)
> > > > > > > >
> > > > > > > > diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi b/arch/arm64/
> > > > > boot/dts/allwinner/sun50i-h6.dtsi
> > > > > > > > index 28c77d6872f6..a8853ee7885a 100644
> > > > > > > > --- a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > > > > > > +++ b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > > > > > > @@ -67,6 +67,25 @@ de: display-engine {
> > > > > > > > status = "disabled";
> > > > > > > > };
> > > > > > > >
> > > > > > > > + hdmi_sound: hdmi-sound {
> > > > > > > > + compatible = "simple-audio-card";
> > > > > > > > + simple-audio-card,format = "i2s";
> > > > > > > > + simple-audio-card,name = "sun50i-h6-hdmi";
> > > > > > > > + simple-audio-card,mclk-fs = <128>;
> > > > > > > > + simple-audio-card,frame-inversion;
> > > > > > > > + status = "disabled";
> > > > > > > > +
> > > > > > > > + simple-audio-card,codec {
> > > > > > > > + sound-dai = <&hdmi>;
> > > > > > > > + };
> > > > > > > > +
> > > > > > > > + simple-audio-card,cpu {
> > > > > > > > + sound-dai = <&i2s1>;
> > > > > > > > + dai-tdm-slot-num = <2>;
> > > > > > > > + dai-tdm-slot-width = <32>;
> > > > > > >
> > > > > > > It looks weird to have both some TDM setup here, and yet the format in
> > > > > > > i2s?
>
>
> I was looking at sound documentation regarding how I can properly
> write the multi-lane I2S support.
> And I think we made a wrong interpretation here.
>
> TDM slot-num and slot-width are not referencing the format called PCM
> or DSP_A / DSP_B.
> But really the physical time division representation of a format.
>
> For example Amlogic do the following representation for Multi-lane I2S:
>
> dai-link-7 {
> sound-dai = <&tdmif_b>;
> dai-format = "i2s";
> dai-tdm-slot-tx-mask-0 = <1 1>;
> dai-tdm-slot-tx-mask-1 = <1 1>;
> dai-tdm-slot-tx-mask-2 = <1 1>;
> dai-tdm-slot-tx-mask-3 = <1 1>;
> mclk-fs = <256>;
>
> codec {
> sound-dai = <&tohdmitx TOHDMITX_I2S_IN_B>;
> };
> };
>
> So i think for 2 channels HDMI using the simple sound card with TDM
> property is not a hack but the correct way to represent it.
>
> Do you agree ?
>
> If so, can I resend the simple sound card for HDMI audio ?

I mean, it's not less weird :)

And like I said before we still have the option to write a card driver
ourselves that doesn't take anything from the DT beside the phandle of
the i2s controller and the HDMI controller.

If it's a fixed configuration, I'm not sure why we bother trying to make
it dynamic in the DT.

Maxime

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2020-11-02 11:22:42

by Clément Péron

[permalink] [raw]

Subject: Re: [PATCH v4 09/22] arm64: dts: allwinner: h6: Add HDMI audio node

Hi Maxime,

On Mon, 2 Nov 2020 at 11:21, Maxime Ripard <[email protected]> wrote:
>
> On Sun, Nov 01, 2020 at 04:27:05PM +0100, Clément Péron wrote:
> > On Wed, 30 Sep 2020 at 12:19, Maxime Ripard <[email protected]> wrote:
> > >
> > > On Mon, Sep 28, 2020 at 04:27:42PM +0200, Clément Péron wrote:
> > > > On Mon, 28 Sep 2020 at 10:43, Maxime Ripard <[email protected]> wrote:
> > > > >
> > > > > On Mon, Sep 21, 2020 at 08:37:09PM +0200, Jernej Škrabec wrote:
> > > > > > Dne ponedeljek, 21. september 2020 ob 19:23:49 CEST je Clément Péron
> > > > > > napisal(a):
> > > > > > > Hi Maxime,
> > > > > > >
> > > > > > > On Mon, 21 Sep 2020 at 15:59, Maxime Ripard <[email protected]> wrote:
> > > > > > > >
> > > > > > > > On Mon, Sep 21, 2020 at 12:27:18PM +0200, Clément Péron wrote:
> > > > > > > > > From: Jernej Skrabec <[email protected]>
> > > > > > > > >
> > > > > > > > > Add a simple-soundcard to link audio between HDMI and I2S.
> > > > > > > > >
> > > > > > > > > Signed-off-by: Jernej Skrabec <[email protected]>
> > > > > > > > > Signed-off-by: Marcus Cooper <[email protected]>
> > > > > > > > > Signed-off-by: Clément Péron <[email protected]>
> > > > > > > > > ---
> > > > > > > > > arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi | 33 ++++++++++++++++++++
> > > > > > > > > 1 file changed, 33 insertions(+)
> > > > > > > > >
> > > > > > > > > diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi b/arch/arm64/
> > > > > > boot/dts/allwinner/sun50i-h6.dtsi
> > > > > > > > > index 28c77d6872f6..a8853ee7885a 100644
> > > > > > > > > --- a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > > > > > > > +++ b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > > > > > > > @@ -67,6 +67,25 @@ de: display-engine {
> > > > > > > > > status = "disabled";
> > > > > > > > > };
> > > > > > > > >
> > > > > > > > > + hdmi_sound: hdmi-sound {
> > > > > > > > > + compatible = "simple-audio-card";
> > > > > > > > > + simple-audio-card,format = "i2s";
> > > > > > > > > + simple-audio-card,name = "sun50i-h6-hdmi";
> > > > > > > > > + simple-audio-card,mclk-fs = <128>;
> > > > > > > > > + simple-audio-card,frame-inversion;
> > > > > > > > > + status = "disabled";
> > > > > > > > > +
> > > > > > > > > + simple-audio-card,codec {
> > > > > > > > > + sound-dai = <&hdmi>;
> > > > > > > > > + };
> > > > > > > > > +
> > > > > > > > > + simple-audio-card,cpu {
> > > > > > > > > + sound-dai = <&i2s1>;
> > > > > > > > > + dai-tdm-slot-num = <2>;
> > > > > > > > > + dai-tdm-slot-width = <32>;
> > > > > > > >
> > > > > > > > It looks weird to have both some TDM setup here, and yet the format in
> > > > > > > > i2s?
> >
> >
> > I was looking at sound documentation regarding how I can properly
> > write the multi-lane I2S support.
> > And I think we made a wrong interpretation here.
> >
> > TDM slot-num and slot-width are not referencing the format called PCM
> > or DSP_A / DSP_B.
> > But really the physical time division representation of a format.
> >
> > For example Amlogic do the following representation for Multi-lane I2S:
> >
> > dai-link-7 {
> > sound-dai = <&tdmif_b>;
> > dai-format = "i2s";
> > dai-tdm-slot-tx-mask-0 = <1 1>;
> > dai-tdm-slot-tx-mask-1 = <1 1>;
> > dai-tdm-slot-tx-mask-2 = <1 1>;
> > dai-tdm-slot-tx-mask-3 = <1 1>;
> > mclk-fs = <256>;
> >
> > codec {
> > sound-dai = <&tohdmitx TOHDMITX_I2S_IN_B>;
> > };
> > };
> >
> > So i think for 2 channels HDMI using the simple sound card with TDM
> > property is not a hack but the correct way to represent it.
> >
> > Do you agree ?
> >
> > If so, can I resend the simple sound card for HDMI audio ?
>
> I mean, it's not less weird :)
>
> And like I said before we still have the option to write a card driver
> ourselves that doesn't take anything from the DT beside the phandle of
> the i2s controller and the HDMI controller.
>
> If it's a fixed configuration, I'm not sure why we bother trying to make
> it dynamic in the DT.

Ok I see what you mean here, as the link is hardcoded in the SoC it's
a better representation to hardcode it in the sound card driver than
having it dynamically represented in each board device-tree.

Sounds correct for me,
Thanks :)

>
> Maxime