Re: [PATCH v2] arm64: dts: qcom: hamoa-iot-evk: switch typec0 to PS8830 retimer

[Xin Liu]

On 8/4/2026 3:35 AM, Dmitry Baryshkov wrote:
> On Mon, Aug 03, 2026 at 06:27:47AM -0700, Xin Liu wrote:
> > The Hamoa IoT EVK hardware design uses a Parade PS8830 retimer on
> > I2C3 for USB Type-C port 0. Describe the retimer and route typec0
> > through it to enable USB 3.0 SuperSpeed and DisplayPort Alt Mode.
> >
> > Supply the PS8830 from the existing vreg_rtmr0_* rails and remove
> > their stale "Left unused" annotation.
> >
> > The FSUSB42 SBU mux chip is present on the PCB but with all signal
> > lines unconnected (NC), so remove the fsusb42 node and its pinctrl
> > group.
> Why is it still present on the PCB?

The FSUSB42 is retained on the PCB as a fallback for the PS8830's SBU 
mux function.

Should the PS8830's SBU path encounter any issues, the FSUSB42 can 
be activated

with a simple rework to quickly switch to a discrete solution, avoiding 
a full board respin.


Thanks,
Xin

> > Tested on the Hamoa IoT EVK:
> >
> > USB 3.0 SuperSpeed at 5 Gbps on typec0
> > DisplayPort Alt Mode on typec0
> >
> > Signed-off-by: Guodong Xu <guodong.xu@xxxxxxxxxxxxxxxx>
> > Signed-off-by: Xin Liu <xin.liu@xxxxxxxxxxxxxxxx>
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>