On Sat, Feb 4, 2023 at 9:31 PM Pin-yen Lin <treapking@xxxxxxxxxxxx> wrote:
>
> ITE IT6505 can be used in systems to switch the DP traffic between
> two downstreams, which can be USB Type-C DisplayPort alternate mode
> lane or regular DisplayPort output ports.
>
> Update the binding to accommodate this usage by introducing a
> data-lanes and a mode-switch property on endpoints.
>
> Signed-off-by: Pin-yen Lin <treapking@xxxxxxxxxxxx>
>
> ---
>
> Changes in v11:
> - Updated the description of the endpoints in the bindings
> - Referenced video-interfaces.yaml instead for the endpoints binding
> - Removed duplicated definitions from inherited schema
>
> Changes in v9:
> - Fixed subject prefix again
> - Changed the naming of the example node for it6505
>
> Changes in v8:
> - Updated bindings for data-lanes property
> - Fixed subject prefix
>
> Changes in v7:
> - Fixed issues reported by dt_binding_check.
> - Updated the schema and the example dts for data-lanes.
> - Changed to generic naming for the example dts node.
>
> Changes in v6:
> - Remove switches node and use endpoints and data-lanes property to
> describe the connections.
>
> .../bindings/display/bridge/ite,it6505.yaml | 101 +++++++++++++++---
> 1 file changed, 88 insertions(+), 13 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml b/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
> index b16a9d9127dd..8ae9c5cba22c 100644
> --- a/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
> +++ b/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
> @@ -75,22 +75,49 @@ properties:
> port@1:
> $ref: /schemas/graph.yaml#/$defs/port-base
> unevaluatedProperties: false
> - description: Video port for DP output
> + description:
> + Video port for DP output. Each endpoint connects to a video output
> + downstream, and the "data-lanes" property is used to describe the pin
> + connections. 0, 1, 2, 3 in "data-lanes" maps to TX0, TX1, TX2, TX3,
> + respectively.
>
> - properties:
> - endpoint:
> - $ref: /schemas/graph.yaml#/$defs/endpoint-base
> +
> + patternProperties:
> + "^endpoint@[01]$":
> + $ref: /schemas/media/video-interfaces.yaml#
> unevaluatedProperties: false
>
> properties:
> + reg: true
> +
> + remote-endpoint: true
> +
> data-lanes:
> - minItems: 1
> - uniqueItems: true
> - items:
> - - enum: [ 0, 1 ]
> - - const: 1
> - - const: 2
> - - const: 3
> + oneOf:
> + - items:
> + - enum: [0, 1, 2, 3]
Based on the datasheets we have and the downstream driver, I assume
the hardware implements "lane swap" as simply reversing the order
of the output pins.
In that case the hardware can't output 1 lane DP on any arbitrary lane,
but only lane 0 or 3.
> + - items:
> + - const: 0
> + - const: 1
> +
> + - items:
> + - const: 2
> + - const: 3
And maybe a bit pedantic, but have the order correct as:
- const: 3
- const: 2
> + - items:
> + - const: 0
> + - const: 1
> + - const: 2
> + - const: 3
> +
> + mode-switch:
> + type: boolean
> + description: Register this node as a Type-C mode switch or not.
Same as the anx7625 patch, I would reword this as "Serves as Type-C mode
switch if present".
ChenYu
> +
> + required:
> + - reg
> + - remote-endpoint
>
> required:
> - port@0
> @@ -102,7 +129,6 @@ required:
> - pwr18-supply
> - interrupts
> - reset-gpios
> - - extcon
> - ports
>
> additionalProperties: false
> @@ -139,8 +165,11 @@ examples:
> };
>
> port@1 {
> + #address-cells = <1>;
> + #size-cells = <0>;
> reg = <1>;
> - it6505_out: endpoint {
> + it6505_out: endpoint@0 {
> + reg = <0>;
> remote-endpoint = <&dp_in>;
> data-lanes = <0 1>;
> };
> @@ -148,3 +177,49 @@ examples:
> };
> };
> };
> + - |
> + #include <dt-bindings/interrupt-controller/irq.h>
> +
> + i2c {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + dp-bridge@5c {
> + compatible = "ite,it6505";
> + interrupts = <8 IRQ_TYPE_LEVEL_LOW 8 0>;
> + reg = <0x5c>;
> + pinctrl-names = "default";
> + pinctrl-0 = <&it6505_pins>;
> + ovdd-supply = <&mt6366_vsim2_reg>;
> + pwr18-supply = <&pp1800_dpbrdg_dx>;
> + reset-gpios = <&pio 177 0>;
> +
> + ports {
> + #address-cells = <1>;
> + #size-cells = <0>;
> + port@0 {
> + reg = <0>;
> + it6505_dpi_in: endpoint {
> + remote-endpoint = <&dpi_out>;
> + };
> + };
> + port@1 {
> + #address-cells = <1>;
> + #size-cells = <0>;
> + reg = <1>;
> + ite_typec0: endpoint@0 {
> + reg = <0>;
> + mode-switch;
> + data-lanes = <0 1>;
> + remote-endpoint = <&typec_port0>;
> + };
> + ite_typec1: endpoint@1 {
> + reg = <1>;
> + mode-switch;
> + data-lanes = <2 3>;
> + remote-endpoint = <&typec_port1>;
> + };
> + };
> + };
> + };
> + };
> --
> 2.39.1.519.gcb327c4b5f-goog
>
