Re: [PATCH v7 2/3] ASoC: qcom: dt-bindings: Add sc7180 machine bindings - Cheng-yi Chiang

From: Cheng-yi Chiang <cychiang@chromium.org>
To: Rob Herring <robh@kernel.org>
Cc: linux-kernel <linux-kernel@vger.kernel.org>,
	Mark Brown <broonie@kernel.org>, Taniya Das <tdas@codeaurora.org>,
	Rohit kumar <rohitkr@codeaurora.org>,
	Banajit Goswami <bgoswami@codeaurora.org>,
	Patrick Lai <plai@codeaurora.org>, Andy Gross <agross@kernel.org>,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	Liam Girdwood <lgirdwood@gmail.com>,
	Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.com>,
	Srini Kandagatla <srinivas.kandagatla@linaro.org>,
	Stephan Gerhold <stephan@gerhold.net>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	Heiko Stuebner <heiko@sntech.de>,
	Doug Anderson <dianders@chromium.org>,
	Dylan Reid <dgreid@chromium.org>,
	Tzung-Bi Shih <tzungbi@chromium.org>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>,
	linux-arm-msm <linux-arm-msm@vger.kernel.org>,
	"open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
	<devicetree@vger.kernel.org>,
	"moderated list:SOUND - SOC LAYER / DYNAMIC AUDIO POWER
	MANAGEM..."  <alsa-devel@alsa-project.org>,
	linux-mediatek@lists.infradead.org,
	linux-rockchip@lists.infradead.org
Subject: Re: [PATCH v7 2/3] ASoC: qcom: dt-bindings: Add sc7180 machine bindings
Date: Wed, 9 Sep 2020 18:19:16 +0800	[thread overview]
Message-ID: <CAFv8NwJXyzUsCQZu1cU0t7NUJDpS_DyxZM=ZhU+jGoQj97i3Jw@mail.gmail.com> (raw)
In-Reply-To: <CAFv8NwLMAkFhVT-ML7QHbnSkqmgh=5SrNSik5eSCTHB1=DGQ0A@mail.gmail.com>

On Wed, Sep 9, 2020 at 5:23 PM Cheng-yi Chiang <cychiang@chromium.org> wrote:
>
> On Wed, Sep 9, 2020 at 4:34 AM Rob Herring <robh@kernel.org> wrote:
> >
> > On Mon, Sep 07, 2020 at 06:00:38PM +0800, Cheng-Yi Chiang wrote:
> > > Add devicetree bindings documentation file for sc7180 sound card.
> > >
> > > Signed-off-by: Cheng-Yi Chiang <cychiang@chromium.org>
> > > ---
> > >  .../bindings/sound/qcom,sc7180.yaml           | 143 ++++++++++++++++++
> > >  1 file changed, 143 insertions(+)
> > >  create mode 100644 Documentation/devicetree/bindings/sound/qcom,sc7180.yaml
> > >
> > > diff --git a/Documentation/devicetree/bindings/sound/qcom,sc7180.yaml b/Documentation/devicetree/bindings/sound/qcom,sc7180.yaml
> > > new file mode 100644
> > > index 000000000000..ae809346ca80
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/sound/qcom,sc7180.yaml
> > > @@ -0,0 +1,143 @@
> > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > > +%YAML 1.2
> > > +---
> > > +$id: http://devicetree.org/schemas/sound/qcom,sc7180.yaml#
> > > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > > +
> > > +title: Qualcomm Technologies Inc. SC7180 ASoC sound card driver
> > > +
> > > +maintainers:
> > > +  - Rohit kumar <rohitkr@codeaurora.org>
> > > +  - Cheng-Yi Chiang <cychiang@chromium.org>
> > > +
> > > +description:
> > > +  This binding describes the SC7180 sound card which uses LPASS for audio.
> > > +
> > > +properties:
> > > +  compatible:
> > > +    const: qcom,sc7180-sndcard
> > > +
> > > +  audio-routing:
> > > +    $ref: /schemas/types.yaml#/definitions/non-unique-string-array
> > > +    description:
> > > +      A list of the connections between audio components. Each entry is a
> > > +      pair of strings, the first being the connection's sink, the second
> > > +      being the connection's source.
> > > +
> > > +  model:
> > > +    $ref: /schemas/types.yaml#/definitions/string
> > > +    description: User specified audio sound card name
> > > +
> > > +  headset-jack:
> > > +    $ref: /schemas/types.yaml#/definitions/phandle
> > > +    description: phandle of the codec for headset detection
> > > +
> > > +  hdmi-jack:
> > > +    $ref: /schemas/types.yaml#/definitions/phandle
> > > +    description: phandle of the codec for hdmi jack detection
> >
> > You already have links to these devices. Why duplicate it here?
> >
> > What if you had 2 headsets? This doesn't scale.
> >
> Hi Rob, thanks for reviewing.
> There was some discussion in
> https://patchwork.kernel.org/patch/11737905/#23571643 about how to
> specify the dailink that has a headset jack.
> I would like to pass the information of headset jack and hdmi jack to
> the machine driver so the machine driver can call
> snd_soc_component_set_jack to set jack when init the corresponding link.
> Headset jack and hdmi jack will be treated differently for button and
> event type.
> Because of this, we can not just set a property "jack" in the link.
>
> As for the 2 headsets case (I guess you mean hp jack and mic jack), on
> this board we will not have this use case.
> If someone really wants to build hp jack and mic jack on the board
> based on this machine driver, we can add two more property hp-jack and
> mic-jack to specify that,
> as the machine driver will need to know the different jack types
> anyway. What do you think ?
>
> Or could you please suggest a proper way to pass such information ?
>
> Thanks!
> >
Alternatively we can probably do

                dai-link@0 {
                        link-name = "MultiMedia0";
                        reg = <0>;
                        cpu {
                                sound-dai = <&lpass_cpu 0>;
                        };
                        headset_jack;
                        codec {
                                sound-dai = <&alc5682 0>;
                        };
                };
                dai-link@2 {
                        link-name = "MultiMedia2";
                        reg = <2>;
                        cpu {
                                sound-dai = <&lpass_hdmi 0>;
                        };
                        hdmi_jack;
                        codec {
                                sound-dai = <&msm_dp>;
                        };
                };

Or even put the flag into codec {}.
Please let me know if you feel this is a better way.
I think it will make the driver code a little more complicated, but
the interface on dts might looks cleaner.
Thanks!

> > Rob