Re: [PATCH v2 07/18] arm64: dts: ti: k3-j721e: Add overlay for fusion application daughter board

[Yemike Abhilash Chandra]

Hi Udit,
Thanks for the review.

On 27/07/26 10:59, Kumar, Udit wrote:
> Thanks for patch
>
> On 7/13/2026 5:04 PM, Yemike Abhilash Chandra wrote:
> > From: Vaishnav Achath <vaishnav.a@xxxxxx>
> >
> > Fusion application daughter board [1] can be used to connect multiple
> > FPDLink-III based sensors to TI EVMs. The board has two DS90UB960
> > deserializers, each of which aggregates input from up to 4x FPDLink-III
> > sensors. Up to 8x sensors can simultaneously stream over the two CSI RX
> > ports on J721E.
> J721E to same of board, please
>
> > [1]: https://svtronics.com/product/fusion-application-daughter-board-evm577pfusion-v1-0/?srsltid=AfmBOooMsRAd5ibFOGJaKbjsC3j9-loTPK2wWqsqPq2Adj55g1nPluxX
> >
> > Signed-off-by: Vaishnav Achath <vaishnav.a@xxxxxx>
> > Signed-off-by: Yemike Abhilash Chandra <y-abhilashchandra@xxxxxx>
> > ---
> > Changelog:
> > Changes in v2:
> > - Add missing bus-type property in csi2_phy0 endpoint for cdns_csi2rx0 (sashiko)
> > - Fix minor DTS styling and whitespace inconsistencies in port definitions (sashiko)
> > - Remove unused gpio.h header (sashiko)
> >
> >   arch/arm64/boot/dts/ti/Makefile               |   4 +
> > [..]
> > +		deserializer_0_ports: ports {
> > +			#address-cells = <1>;
> > +			#size-cells = <0>;
> > +
> > +			port@0 {
> > +				reg = <0>;
> > +				status = "disabled";
> > +			};
> > +
> > +			port@1 {
> > +				reg = <1>;
> > +				status = "disabled";
> > +			};
> > +
> > +			port@2 {
> > +				reg = <2>;
> > +				status = "disabled";
> > +			};
> > +
> > +			port@3 {
> > +				reg = <3>;
> > +				status = "disabled";
> > +			};
> > +
> > +			/* CSI-2 TX */
> > +			port@4 {
> > +				reg = <4>;
> > +				ds90ub960_0_csi_out: endpoint {
> > +					data-lanes = <1 2 3 4>;
> > +					clock-lanes = <0>;
> > +					link-frequencies = /bits/ 64 <800000000>;
> > +					remote-endpoint = <&csi2_phy0>;
> > +				};
> > +			};
> > +
> > +			port@5 {
> > +				reg = <5>;
> > +				status = "disabled";
> > +			};
>
> Little confused here on port number,
> I am wondering, why 5 ports are defined.
>
> as per DS90UB960, one single part can have 4 input (from sensors)
> and 2 port output (towards SOC) page 5 from [0].

The DS90UB960 has 4 input ports (RX) and 2 output ports (TX).

Hence we define input ports starting from port 0 till port 3.
Port 4 and 5 correspond to the two output ports.

So the ports definition here include both input and output ports
of the DS90UB960.

Thanks and Regards,
Yemike Abhilash Chandra

> https://www.ti.com/lit/ds/symlink/ds90ub960-q1.pdf
>
>
> > +		};
> > +
> > [..]