Re: [PATCH v4 3/6] arm64: dts: qcom: Add AYN QCS8550 Common

[Dmitry Baryshkov]

On Mon, Mar 30, 2026 at 01:00:55PM +0200, Konrad Dybcio wrote:
> On 3/27/26 10:26 PM, Aaron Kling wrote:
> > On Tue, Mar 24, 2026 at 7:36 AM Konrad Dybcio
> > <konrad.dybcio@xxxxxxxxxxxxxxxx> wrote:
> >>
> >> On 3/23/26 5:27 PM, Aaron Kling via B4 Relay wrote:
> >>> From: Teguh Sobirin <teguh@xxxxxxxx>
> >>>
> >>> This contains everything common between the AYN QCS8550 devices. It will
> >>> be included by device specific dts'.
> >>>
> >>> Signed-off-by: Teguh Sobirin <teguh@xxxxxxxx>
> >>> Co-developed-by: Aaron Kling <webgeek1234@xxxxxxxxx>
> >>> Signed-off-by: Aaron Kling <webgeek1234@xxxxxxxxx>
> >>> ---
> >>
> >> [...]
> >>
> >>> +     sound {
> >>> +             compatible = "qcom,sm8550-sndcard", "qcom,sm8450-sndcard";
> >>> +             pinctrl-0 = <&lpi_i2s3_active>;
> >>> +             pinctrl-names = "default";
> >>> +
> >>> +             model = "AYN-Odin2";
> >>
> >> Is this enough of a distinction? Do you need to make any changes to the
> >> one with a HDMI bridge to get HDMI audio?
> > 
> > After this quesstion, I tried to verify hdmi and am unable to even get
> > the connector to come up. The lt8912b driver complains that the
> > connector doesn't support edid read.

Looking at the driver, please drop lt8912_bridge_edid_read(),
lt8912_bridge_detect() and lt->bridge.ops assignment. Those bits are
lame and useless.

> Which per the current connector
> > node is correct, none of the devices list a ddc node. I am trying to
> > investigate this further, but vendor source release unfortunately
> > appears to be missing pieces related to this. And no other current
> > qcom device uses this bridge to take a guess at which controller the
> > ddc is on.
> 
> Go through the I2C buses that are enabled on the vendor kernel and try
> inspecting them with toos like i2cdetect

I'd second this suggestion. The chip doesn't support EDID reading, so it
is (hopefully) handled via some existing bus. Does downstream handle
EDID / HDMI at all?

> 
> > 
> > On a related note, I'm not sure hdmi is covered in the audio topology.
> 
> Since this is a DSI bridge, I'd imagine it needs a separate connection
> to the SoC's sound hardware. We've had similar occurences in the past,
> e.g. this on the SM8250 RB5 board (qrb5165-rb5.dts):

Yes. Unfortunately, the driver doesn't seem to implement audio support.
I'd suggest pinging Lontium for the information regarding InfoFrame and
audio bits programming.

> 
> https://github.com/alsa-project/alsa-ucm-conf/blob/master/ucm2/Qualcomm/sm8250/HDMI.conf
> 
> Maybe +Dmitry could help you out
> 
> Konrad
> 
> > What I'm using is here [0]. This is in a fork of the topology repo
> > with aosp build rules added. Speakers work, headphones out and in
> > work. DP works only with the pending q6dsp fixups series, which I
> > should probably narrow down and ask for a 6.18 backport for. The ucm
> > config [1] I'm basing tests on doesn't handle the built-in mic and I
> > haven't been able to figure that out yet, so that's also unknown.
> > 
> > Aaron
> > 
> > [0] https://github.com/LineageOS/android_hardware_qcom_audioreach-topology/blob/ad67f3777b1d4dec5289bc7117f2ec34521be7e6/AYN-Odin2.m4
> > [1] https://github.com/AYNTechnologies/alsa-ucm-conf/commit/d33738b93e9560e8d9e08a024cc84c8055bb7eb9

-- 
With best wishes
Dmitry