[PATCH v3 16/17] platform/chrome: cros_ec_typec: Support DP muxing

[Andy Shevchenko]

On Fri, Aug 23, 2024 at 01:44:41PM -0700, Stephen Boyd wrote:
> Quoting Tzung-Bi Shih (2024-08-22 07:37:05)
> > On Mon, Aug 19, 2024 at 03:38:30PM -0700, Stephen Boyd wrote:

...

> > > +     /*
> > > +      * Assume the first port to have HPD asserted is the one muxed to DP
> > > +      * (i.e. active_port). When there's only one port this delays setting
> > > +      * the active_port until HPD is asserted, but before that the
> > > +      * drm_connector looks disconnected so active_port doesn't need to be
> > > +      * set.
> > > +      */
> > > +     if (dp_bridge && hpd_asserted && !dp_bridge->active_port)
> > > +             dp_bridge->active_port = port;
> > > +
> > > +     is_active_port = !dp_bridge || dp_bridge->active_port == port;
> >
> > Why `!dp_bridge`?  When will `dp_bridge` be NULL?
> 
> I'll add a comment.
> 
> 'dp_bridge' is NULL when this driver is running on non-DT platforms,
> i.e. ACPI, or there isn't a graph/ports node for this device. The latter
> could happen if there's some AP controlled piece of hardware that is a
> typec switch, connected directly to a usb-c-connector. This is the case
> on Kukui where we send the DP lanes directly to the usb-c-connector.

Thanks!

-- 
With Best Regards,
Andy Shevchenko