Re: [PATCH v4 4/5] dt-bindings: display: Add Synaptics R63455 panel support

[Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>]

On Thu, May 21, 2026 at 10:46:06PM +0800, Jun Nie wrote:
> Add support for the dual-panel system found in the virtual reality device.
> This system consists of two physical 2160x2160 panels, each connected via
> a MIPI DSI interface. The backlight is managed through DSI link.
> 
> Signed-off-by: Jun Nie <jun.nie@linaro.org>
> ---
>  .../bindings/display/panel/synaptics,r63455.yaml   | 125 +++++++++++++++++++++
>  1 file changed, 125 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/display/panel/synaptics,r63455.yaml b/Documentation/devicetree/bindings/display/panel/synaptics,r63455.yaml
> new file mode 100644
> index 0000000000000..a94b355ed9557
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/panel/synaptics,r63455.yaml
> @@ -0,0 +1,125 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/panel/synaptics,r63455.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Synaptics R63455 based dual 2160x2160 MIPI-DSI Panel
> +
> +maintainers:
> +  - Jun Nie <jun.nie@linaro.org>
> +
> +description:
> +  Synaptics R63455 is a Virtual Reality Display Driver and VR Bridge, used in
> +  pair in Headset devices. The Virtual Reality Display complex is composed of
> +  two strictly identical display panels, each driven by its own DSI interface
> +  but forms a single virtual display for the human eye perception and thus
> +  requires a strict synchronization of the two display panel content update.
> +
> +allOf:
> +  - $ref: panel-common.yaml#
> +
> +properties:
> +  compatible:
> +    items:
> +      - enum:
> +        - sharp,ls026b3sa06
> +        - boe,vs026c4m-n52-6000
> +      - const: synaptics,r63455
> +
> +  reset-gpios:
> +    maxItems: 2
> +    description: 2 reset pins for 2 physical panels
> +
> +  left-pos-supply:
> +    description: Positive 5.7V supply for left panel

So, is the R63455 driving both panels or are there two panels, each
having R63455 controller? What if somebody gets a single Sharp panel and
wants to use it in their device? How will it match these bindings?

> +
> +  right-pos-supply:
> +    description: Positive 5.7V supply for right panel
> +
> +  left-neg-supply:
> +    description: Negative 5.7V supply for left panel
> +
> +  right-neg-supply:
> +    description: Negative 5.7V supply for right panel
> +
> +  left-backlight-supply:
> +    description: Backlight 21V supply for left panel
> +
> +  right-backlight-supply:
> +    description: Backlight 21V supply for right panel
> +
> +  vdda-supply:
> +    description: core 1.8V supply for panels
> +
> +  ports: $ref: /schemas/graph.yaml#/properties/ports
> +
> +required:
> +  - compatible
> +  - reset-gpios
> +  - left-pos-supply
> +  - left-neg-supply
> +  - right-pos-supply
> +  - right-neg-supply
> +  - left-backlight-supply
> +  - right-backlight-supply
> +  - vdda-supply
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +
> +    &mdss_dsi0 {

Please drop the MDSS specifics, there should be one (or two) DSI busses,
driving your panels. The rests are details which are not necessary for
the example.

> +        vdda-supply = <&vreg_l3i_1p2>;
> +        status = "okay";
> +
> +        qcom,dual-dsi-mode;
> +        qcom,master-dsi;
> +
> +        panel: panel@0 {
> +            compatible = "sharp,ls026b3sa06", "synaptics,r63455";
> +            reg = <0>;
> +
> +            reset-gpios = <&pm8550_gpios 3 GPIO_ACTIVE_HIGH>,
> +                          <&pm8550_gpios 11 GPIO_ACTIVE_HIGH>;
> +
> +            left-pos-supply = <&vpos_left>;
> +            left-neg-supply = <&vneg_left>;
> +            right-pos-supply = <&vpos_right>;
> +            right-neg-supply = <&vneg_right>;
> +            left-backlight-supply = <&backlight_left>;
> +            right-backlight-supply = <&backlight_right>;
> +
> +            vdda-supply = <&vreg_l12b_1p8>;
> +
> +            ports {
> +                #address-cells = <1>;
> +                #size-cells = <0>;
> +                port@0 {
> +                    reg = <0>;
> +                    panel0_in: endpoint {
> +                        remote-endpoint = <&mdss_dsi0_out>;

What is mdss_dsi0_out?

> +                    };
> +                };
> +
> +                port@1 {
> +                    reg = <1>;
> +                    panel1_in: endpoint {
> +                        remote-endpoint = <&mdss_dsi1_out>;
> +                    };
> +                };
> +            };
> +    };
> +
> +    &mdss_dsi0_out {
> +            remote-endpoint = <&panel0_in>;
> +            data-lanes = <0 1 2>;
> +    };
> +
> +    &mdss_dsi1_out {
> +            remote-endpoint = <&panel1_in>;
> +            data-lanes = <0 1 2>;
> +    };
> +...
> 
> -- 
> 2.43.0
> 

-- 
With best wishes
Dmitry