[PATCH] dt-bindings: dp-connector: add binding for DisplayPort connector

[Laurent Pinchart]

Hi Tomi,

Thank you for the patch.

On Wed, Sep 16, 2020 at 05:44:40PM +0300, Tomi Valkeinen wrote:
> Add binding for DisplayPort connector. A few notes:
> 
> * Similar to hdmi-connector, it has hpd-gpios as an optional property,
>   as the HPD could also be handled by, e.g., the DP bridge.
> 
> * dp-pwr-supply, which provides 3.3V on DP_PWR pin, is optional, as it
>   is not strictly required: standard DP cables do not even have the pin
>   connected.
> 
> * No property for the connector type. Full size and mini connectors are
>   identical except for the connector size and form, so I believe there
>   is no need to include the type in the bindings.

It could be useful to present information about the connector to
userspace. For instance, a GUI could show a picture of the connector
that the user should plug a cable in. This can also be added later, but
I think it would be useful to have it from the start.

> * No eDP. There's really no "eDP connector", as it's always a custom
>   made connection between the DP and the DP panel. So possibly there is
>   no need for edp-connector binding, but even if there is, I don't want
>   to guess what it could look like, and could it be part of the
>   dp-connector binding.

Agreed.

> * No DP++. I'm not familiar with DP++, but I think it's all handled by
>   the DP bridge, and does not need any new properties to the dp-connector.

I'm not familiar with this either.

> Signed-off-by: Tomi Valkeinen <tomi.valkeinen at ti.com>

Possibly with a type property added,

Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

> ---
>  .../display/connector/dp-connector.yaml       | 48 +++++++++++++++++++
>  1 file changed, 48 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/connector/dp-connector.yaml
> 
> diff --git a/Documentation/devicetree/bindings/display/connector/dp-connector.yaml b/Documentation/devicetree/bindings/display/connector/dp-connector.yaml
> new file mode 100644
> index 000000000000..983be1fe43f0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/connector/dp-connector.yaml
> @@ -0,0 +1,48 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/connector/dp-connector.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: DisplayPort Connector
> +
> +maintainers:
> +  - Tomi Valkeinen <tomi.valkeinen at ti.com>
> +
> +properties:
> +  compatible:
> +    const: dp-connector
> +
> +  label: true
> +
> +  hpd-gpios:
> +    description: A GPIO line connected to HPD
> +    maxItems: 1
> +
> +  dp-pwr-supply:
> +    description: Power supply for the DP_PWR pin
> +    maxItems: 1
> +
> +  port:
> +    description: Connection to controller providing DP signals
> +
> +required:
> +  - compatible
> +  - port
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    connector {
> +        compatible = "dp-connector";
> +        label = "dp0";
> +
> +        port {
> +            dp_connector_in: endpoint {
> +                remote-endpoint = <&dp_out>;
> +            };
> +        };
> +    };
> +
> +...

-- 
Regards,

Laurent Pinchart