Re: [PATCH v2 5/9] dt-bindings: display: bridge: Add ITE IT6263 LVDS to HDMI converter

[Liu Ying]

On 10/12/2024, Dmitry Baryshkov wrote:
> On Sat, Oct 12, 2024 at 03:35:39PM +0800, Liu Ying wrote:
>> Document ITE IT6263 LVDS to HDMI converter.
>>
>> Product link:
>> https://www.ite.com.tw/en/product/cate1/IT6263
>>
>> Signed-off-by: Liu Ying <victor.liu@xxxxxxx>
>> ---
>> v2:
>> * Document number of LVDS link data lanes.  (Biju)
>> * Simplify ports property by dropping "oneOf".  (Rob)
>>
>>  .../bindings/display/bridge/ite,it6263.yaml   | 276 ++++++++++++++++++
>>  1 file changed, 276 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/display/bridge/ite,it6263.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/display/bridge/ite,it6263.yaml b/Documentation/devicetree/bindings/display/bridge/ite,it6263.yaml
>> new file mode 100644
>> index 000000000000..bc2bbec07623
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/display/bridge/ite,it6263.yaml
>> @@ -0,0 +1,276 @@
>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/display/bridge/ite,it6263.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: ITE IT6263 LVDS to HDMI converter
>> +
>> +maintainers:
>> +  - Liu Ying <victor.liu@xxxxxxx>
>> +
>> +description: |
>> +  The IT6263 is a high-performance single-chip De-SSC(De-Spread Spectrum) LVDS
>> +  to HDMI converter.  Combined with LVDS receiver and HDMI 1.4a transmitter,
>> +  the IT6263 supports LVDS input and HDMI 1.4 output by conversion function.
>> +  The built-in LVDS receiver can support single-link and dual-link LVDS inputs,
>> +  and the built-in HDMI transmitter is fully compliant with HDMI 1.4a/3D, HDCP
>> +  1.2 and backward compatible with DVI 1.0 specification.
>> +
>> +  The IT6263 also encodes and transmits up to 8 channels of I2S digital audio,
>> +  with sampling rate up to 192KHz and sample size up to 24 bits. In addition,
>> +  an S/PDIF input port takes in compressed audio of up to 192KHz frame rate.
>> +
>> +  The newly supported High-Bit Rate(HBR) audio by HDMI specifications v1.3 is
>> +  provided by the IT6263 in two interfaces: the four I2S input ports or the
>> +  S/PDIF input port.  With both interfaces the highest possible HBR frame rate
>> +  is supported at up to 768KHz.
>> +
>> +properties:
> 
> No LVDS data-mapping support?

It is enough to document number of LVDS link data lanes
because OS should be able to determine the data-mapping
by looking at the number and the data-mapping capability
of the other side of the LVDS link. 

> 
>> +  compatible:
>> +    const: ite,it6263
>> +
>> +  reg:
>> +    maxItems: 1
>> +
>> +  clocks:
>> +    maxItems: 1
>> +    description: audio master clock
>> +
>> +  clock-names:
>> +    const: mclk
>> +
>> +  reset-gpios:
>> +    maxItems: 1
>> +
>> +  ivdd-supply:
>> +    description: 1.8V digital logic power
>> +
>> +  ovdd-supply:
>> +    description: 3.3V I/O pin power
>> +
>> +  txavcc18-supply:
>> +    description: 1.8V HDMI analog frontend power
>> +
>> +  txavcc33-supply:
>> +    description: 3.3V HDMI analog frontend power
>> +
>> +  pvcc1-supply:
>> +    description: 1.8V HDMI frontend core PLL power
>> +
>> +  pvcc2-supply:
>> +    description: 1.8V HDMI frontend filter PLL power
>> +
>> +  avcc-supply:
>> +    description: 3.3V LVDS frontend power
>> +
>> +  anvdd-supply:
>> +    description: 1.8V LVDS frontend analog power
>> +
>> +  apvdd-supply:
>> +    description: 1.8V LVDS frontend PLL power
>> +
>> +  "#sound-dai-cells":
>> +    const: 0
>> +
>> +  ite,lvds-link-num-data-lanes:
>> +    $ref: /schemas/types.yaml#/definitions/uint8
>> +    enum: [3, 4, 5]
>> +    description: number of data lanes per LVDS link
> 
> Please use data-lanes property inside the OF graph.

In both port@0 and port@1?

> 
>> +
>> +  ite,i2s-audio-fifo-sources:
>> +    $ref: /schemas/types.yaml#/definitions/uint32-array
>> +    minItems: 1
>> +    maxItems: 4
>> +    items:
>> +      enum: [0, 1, 2, 3]
>> +    description:
>> +      Each array element indicates the pin number of an I2S serial data input
>> +      line which is connected to an audio FIFO, from audio FIFO0 to FIFO3.
> 
> What does that mean from the board point of view? Routed audio links for
> the multichannel audio?

Yes, also for single channel audio.

> 
>> +
>> +  ite,rl-channel-swap-audio-sources:
>> +    $ref: /schemas/types.yaml#/definitions/uint32-array
>> +    minItems: 1
>> +    maxItems: 4
>> +    uniqueItems: true
>> +    items:
>> +      enum: [0, 1, 2, 3]
>> +    description:
>> +      Each array element indicates an audio source whose right channel and left
>> +      channel are swapped by this converter. For I2S, the element is the pin
>> +      number of an I2S serial data input line. For S/PDIF, the element is always
>> +      0.
> 
> Why?

Because this converter has the capability to swap right channel
and left channel and S/PDIF always uses audio source0. 

> 
>> +
>> +  ports:
>> +    $ref: /schemas/graph.yaml#/properties/ports
>> +
>> +    properties:
>> +      port@0:
>> +        $ref: /schemas/graph.yaml#/$defs/port-base
>> +        unevaluatedProperties: false
>> +        description:
>> +          The first LVDS input link.
>> +          In dual-link LVDS mode, this link works together with the second LVDS
>> +          input link, and one link receives odd pixels while the other receives
>> +          even pixels. Specify the pixels with one of the dual-lvds-odd-pixels
>> +          and dual-lvds-even-pixels properties when and only when dual-link LVDS
>> +          mode is used.
>> +
>> +        properties:
>> +          dual-lvds-odd-pixels:
>> +            type: boolean
>> +            description: the first sink port for odd pixels
>> +
>> +          dual-lvds-even-pixels:
>> +            type: boolean
>> +            description: the first sink port for even pixels
>> +
>> +      port@1:
>> +        $ref: /schemas/graph.yaml#/$defs/port-base
>> +        unevaluatedProperties: false
>> +        description: the second LVDS input link
>> +
>> +        properties:
>> +          dual-lvds-even-pixels:
>> +            type: boolean
>> +            description: the second sink port for even pixels
>> +
>> +          dual-lvds-odd-pixels:
>> +            type: boolean
>> +            description: the second sink port for odd pixels
>> +
>> +        oneOf:
>> +          - required: [dual-lvds-even-pixels]
>> +          - required: [dual-lvds-odd-pixels]
> 
> This still allows one to specify that both ports provide odd pixels. Is
> that expected? Also why do you need two properties which specify the
> same option.

No, that is not expected. Description for port@0 already mentions
one link receives odd pixels while the other receives even pixels.

Two options are supported for dual-link LVDS, not the same option:
1) LVDS link1(port@0) gets odd pixels
   and
   LVDS link2(port@1) gets even pixels.

2) LVDS link1(port@0) gets even pixels
   and
   LVDS link2(port@1) gets odd pixels.
That's the reason why each port needs two properties to define
odd/even pixels.

> 
> My suggestion would be to add a single root-level property which
> specifies which port provides even pixel data.

That won't work.  The LVDS source side expects the ports of
the sink side specify dual-lvds-{odd,even}-pixels properties.

> 
>> +
>> +      port@2:
>> +        $ref: /schemas/graph.yaml#/properties/port
>> +        description: video port for the HDMI output
>> +
>> +      port@3:
>> +        $ref: /schemas/graph.yaml#/properties/port
>> +        description: sound input port
>> +
>> +    required:
>> +      - port@0
>> +      - port@2
>> +
>> +required:
>> +  - compatible
>> +  - reg
>> +  - ivdd-supply
>> +  - ovdd-supply
>> +  - txavcc18-supply
>> +  - txavcc33-supply
>> +  - pvcc1-supply
>> +  - pvcc2-supply
>> +  - avcc-supply
>> +  - anvdd-supply
>> +  - apvdd-supply
>> +  - ite,lvds-link-num-data-lanes
>> +  - ports
>> +
>> +additionalProperties: false
>> +
>> +examples:
>> +  - |
>> +    /* single-link LVDS input */
>> +    #include <dt-bindings/gpio/gpio.h>
>> +
>> +    i2c {
>> +        #address-cells = <1>;
>> +        #size-cells = <0>;
>> +
>> +        hdmi@4c {
>> +            compatible = "ite,it6263";
>> +            reg = <0x4c>;
>> +            reset-gpios = <&gpio1 10 GPIO_ACTIVE_LOW>;
>> +            ivdd-supply = <&reg_buck5>;
>> +            ovdd-supply = <&reg_vext_3v3>;
>> +            txavcc18-supply = <&reg_buck5>;
>> +            txavcc33-supply = <&reg_vext_3v3>;
>> +            pvcc1-supply = <&reg_buck5>;
>> +            pvcc2-supply = <&reg_buck5>;
>> +            avcc-supply = <&reg_vext_3v3>;
>> +            anvdd-supply = <&reg_buck5>;
>> +            apvdd-supply = <&reg_buck5>;
>> +            ite,lvds-link-num-data-lanes = /bits/ 8 <4>;
>> +
>> +            ports {
>> +                #address-cells = <1>;
>> +                #size-cells = <0>;
>> +
>> +                port@0 {
>> +                    reg = <0>;
>> +
>> +                    it6263_lvds_link1: endpoint {
>> +                        remote-endpoint = <&ldb_lvds_ch0>;
>> +                    };
>> +                };
>> +
>> +                port@2 {
>> +                    reg = <2>;
>> +
>> +                    it6263_out: endpoint {
>> +                        remote-endpoint = <&hdmi_in>;
>> +                    };
>> +                };
>> +            };
>> +        };
>> +    };
>> +
>> +  - |
>> +    /* dual-link LVDS input */
>> +    #include <dt-bindings/gpio/gpio.h>
>> +
>> +    i2c {
>> +        #address-cells = <1>;
>> +        #size-cells = <0>;
>> +
>> +        hdmi@4c {
>> +            compatible = "ite,it6263";
>> +            reg = <0x4c>;
>> +            reset-gpios = <&gpio1 10 GPIO_ACTIVE_LOW>;
>> +            ivdd-supply = <&reg_buck5>;
>> +            ovdd-supply = <&reg_vext_3v3>;
>> +            txavcc18-supply = <&reg_buck5>;
>> +            txavcc33-supply = <&reg_vext_3v3>;
>> +            pvcc1-supply = <&reg_buck5>;
>> +            pvcc2-supply = <&reg_buck5>;
>> +            avcc-supply = <&reg_vext_3v3>;
>> +            anvdd-supply = <&reg_buck5>;
>> +            apvdd-supply = <&reg_buck5>;
>> +            ite,lvds-link-num-data-lanes = /bits/ 8 <4>;
>> +
>> +            ports {
>> +                #address-cells = <1>;
>> +                #size-cells = <0>;
>> +
>> +                port@0 {
>> +                    reg = <0>;
>> +                    dual-lvds-odd-pixels;
>> +
>> +                    it6263_lvds_link1_dual: endpoint {
>> +                        remote-endpoint = <&ldb_lvds_ch0>;
>> +                    };
>> +                };
>> +
>> +                port@1 {
>> +                    reg = <1>;
>> +                    dual-lvds-even-pixels;
>> +
>> +                    it6263_lvds_link2_dual: endpoint {
>> +                        remote-endpoint = <&ldb_lvds_ch1>;
>> +                    };
>> +                };
>> +
>> +                port@2 {
>> +                    reg = <2>;
>> +
>> +                    it6263_out_dual: endpoint {
>> +                        remote-endpoint = <&hdmi_in>;
>> +                    };
>> +                };
>> +            };
>> +        };
>> +    };
>> -- 
>> 2.34.1
>>
> 

-- 
Regards,
Liu Ying