Re: [PATCH v3 1/2] dt-bindings: display: panel: document Synaptics TDDI panel

[Kaustabh Chakraborty <kauschluss@disroot.org>]

On 2025-08-03 12:02, Dmitry Baryshkov wrote:
> On Sun, Jul 20, 2025 at 05:31:54PM +0530, Kaustabh Chakraborty wrote:
>> Document the Synaptics TDDI (Touch/Display Integration) panel 
>> hardware.
>> Along with the MIPI-DSI panel, these devices also have an in-built LED
>> backlight device and a touchscreen, all packed together in a single 
>> chip.
>> 
>> Also, add compatibles for supported panels - TD4101 and TD4300. Both
>> have the '-panel' suffix so as to remove any ambiguity between the 
>> panel
>> and touchscreen chips.
>> 
>> Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
>> ---
>>  .../display/panel/synaptics,td4300-panel.yaml      | 89 
>> ++++++++++++++++++++++
>>  1 file changed, 89 insertions(+)
>> 
>> diff --git 
>> a/Documentation/devicetree/bindings/display/panel/synaptics,td4300-panel.yaml 
>> b/Documentation/devicetree/bindings/display/panel/synaptics,td4300-panel.yaml
>> new file mode 100644
>> index 
>> 0000000000000000000000000000000000000000..152d94367130e9d80a885fe87a2da53db88e3393
>> --- /dev/null
>> +++ 
>> b/Documentation/devicetree/bindings/display/panel/synaptics,td4300-panel.yaml
>> @@ -0,0 +1,89 @@
>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: 
>> http://devicetree.org/schemas/display/panel/synaptics,td4300-panel.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: Synaptics TDDI Display Panel Controller
>> +
>> +maintainers:
>> +  - Kaustabh Chakraborty <kauschluss@disroot.org>
>> +
>> +allOf:
>> +  - $ref: panel-common.yaml#
>> +
>> +properties:
>> +  compatible:
>> +    enum:
>> +      - syna,td4101-panel
>> +      - syna,td4300-panel
>> +
>> +  reg:
>> +    maxItems: 1
>> +
>> +  vio-supply:
>> +    description: core I/O voltage supply
>> +
>> +  vsn-supply:
>> +    description: negative voltage supply for analog circuits
>> +
>> +  vsp-supply:
>> +    description: positive voltage supply for analog circuits
>> +
>> +  backlight-gpios:
>> +    maxItems: 1
>> +    description: backlight enable GPIO
>> +
>> +  reset-gpios: true
>> +  width-mm: true
>> +  height-mm: true
>> +  panel-timing: true
>> +
>> +required:
>> +  - compatible
>> +  - reg
>> +  - width-mm
>> +  - height-mm
>> +  - panel-timing
>> +
>> +additionalProperties: false
>> +
>> +examples:
>> +  - |
>> +    #include <dt-bindings/gpio/gpio.h>
>> +
>> +    dsi {
>> +        #address-cells = <1>;
>> +        #size-cells = <0>;
>> +
>> +        panel@0 {
>> +            compatible = "syna,td4300-panel";
>> +            reg = <0>;
>> +
>> +            vio-supply = <&panel_vio_reg>;
>> +            vsn-supply = <&panel_vsn_reg>;
>> +            vsp-supply = <&panel_vsp_reg>;
>> +
>> +            backlight-gpios = <&gpd3 5 GPIO_ACTIVE_LOW>;
>> +            reset-gpios = <&gpd3 4 GPIO_ACTIVE_LOW>;
>> +
>> +            width-mm = <68>;
>> +            height-mm = <121>;
>> +
>> +            panel-timing {
> 
> Are the timings defined by the 'TD4300' name or might there be 
> different
> panels with the same name but different timings?

Yes, if I recall correctly, the same panel was used by some Huawei 
phones
with different panel timings. So this is just future-proofing.

> 
>> +                clock-frequency = <144389520>;
>> +
>> +                hactive = <1080>;
>> +                hsync-len = <4>;
>> +                hfront-porch = <120>;
>> +                hback-porch = <32>;
>> +
>> +                vactive = <1920>;
>> +                vsync-len = <2>;
>> +                vfront-porch = <21>;
>> +                vback-porch = <4>;
>> +            };
>> +        };
>> +    };
>> +
>> +...
>> 
>> --
>> 2.50.0
>> 
> 
> --
> With best wishes
> Dmitry