[Freedreno] [[RFC]DPU PATCH 2/4] dt-bindings: drm/bridge: Document sn65dsi86 bridge bindings

[Stephen Boyd]

Quoting Sandeep Panda (2018-04-19 10:56:06)
> Document the bindings used for the sn65dsi86 DSI to eDP bridge.
> 
> Changes in v1:
>  - Rephrase the dt-binding descriptions to be more inline with existing
>    bindings (Andrzej Hajda).
>  - Add missing dt-binding that are parsed by corresponding driver
>    (Andrzej Hajda).
> 
> Changes in v2:
>  - Removed edp panel specific dt-binding entries. Only keep bridge
>    specific entries (Sean Paul).
>  - Remove custom-modes dt entry since its usage is removed from driver also (Sean Paul).
>  - Remove is-pluggable dt entry since this will not be needed anymore (Sean Paul).
> 
> Changes in v3:
>  - Removed irq-gpio dt entry and instead populate is an interrupt
>    property (Rob Herring).

These changelogs usually go below the triple dash, but maybe drm is
different and wants them?

> 
> Signed-off-by: Sandeep Panda <spanda at codeaurora.org>
> ---
>  .../bindings/display/bridge/ti,sn65dsi86.txt       | 61 ++++++++++++++++++++++
>  1 file changed, 61 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/bridge/ti,sn65dsi86.txt
> 
> diff --git a/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi86.txt b/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi86.txt
> new file mode 100644
> index 0000000..412c4a2
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi86.txt
> @@ -0,0 +1,61 @@
> +SN65DSI86 DSI to eDP bridge chip
> +--------------------------------
> +
> +This is the binding for Texas Instruments SN65DSI86 bridge.

Can you add a link to the datasheet here please?

> +
> +Required properties:
> +- compatible: Must be "ti,sn65dsi86"
> +- reg: i2c address of the chip, 0x2d as per datasheet
> +- enable-gpios: OF device-tree gpio specifications for bridge_en pin
> +
> +- vccio-supply: A 1.8V supply that powers up the digital IOs.
> +- vcca-supply: A 1.2V supply that powers up the analog circuits.

Can you add vpll and vcc from the datasheet as well?

Also refclk would be good to have just in case it's present (so
optional?), and hpd should be another gpio property (could be optional I
suppose).

It also looks like this chip has a gpio controller on it, so it would
need to have a gpio-controller property and #gpio-cells. And one of
those GPIOs does PWM, so it would need #pwm-cells as well. I'm not
saying the code needs to be written yet, but at least the binding would
need to specify these things.