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

[Dmitry Baryshkov]

On Sat, Oct 12, 2024 at 05:14:13PM +0800, Liu Ying wrote:
> 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. 

>From what I can see, data-mapping is specified on the consumer sink side
of the LVDS link. This means it should go to the bridge's device node.

> 
> > 
> >> +  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?

Yes

> 
> > 
> >> +
> >> +  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.

That's not expected, but permitted by the bindings.

> 
> 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.

I didn't notice that these properties are already defined.

As these properties are common between several schema files, please
extract them to a common schema file (like lvds.yaml).

> 
> > 
> >> +
> >> +      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
> 

-- 
With best wishes
Dmitry