[PATCHv2] dt-bindings: dp-connector: add binding for DisplayPort connector

[Rob Herring]

On Wed, Sep 23, 2020 at 11:15 AM Tomi Valkeinen <tomi.valkeinen at ti.com> wrote:
>
> Hi Rob,
>
> On 23/09/2020 19:17, Rob Herring wrote:
>
> >> * 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.
> >
> > I don't think that's true. Do an image search for 'edp pinout'. AFAICT,
> > there's 2 lane 30 pin and 4 lane 40 pin. One image says 'Table 5-3 in
> > eDP v1.2'. Of course, I'm sure there's custom ones too. From a binding
> > perspective, we probably don't care about the differences, but just need
> > to be able to describe HPD, backlight power, enable, and pwm, and LCD
> > power.
>
> That's true. The eDP spec lists 4 different standard pinouts (how
> strictly those are followed, I have no idea). But it does not define a
> connector or a cable. And afaik eDP is defined to be not user-detachable.

Yes, but HPD is still used (or sometimes broken). We could just put
that all in panel nodes, but IIRC the last time this came up the issue
was handling devices with different panels stuffed by the
manufacturer. An eDP connector binding would be one way to handle that
as it is somewhat standardized while panel connections aren't at all.

Rob