Re: [PATCH v5 5/9] drm/bridge: anx7625: Add typec_mux_set callback function

From: Stephen Boyd
Date: Thu Jun 30 2022 - 19:21:53 EST


Quoting Prashant Malani (2022-06-28 13:56:22)
> On Tue, Jun 28, 2022 at 1:40 PM Stephen Boyd <swboyd@xxxxxxxxxxxx> wrote:
> >
> > I suppose none of those things matter though as long as there is some
> > typec switch registered here so that the driver can be informed of the
> > pin assignment. Is it right that the "mode-switch" property is only
> > required in DT if this device is going to control the mode of the
> > connector, i.e. USB+DP, or just DP? Where this device can't do that
> > because it doesn't support only DP.
>
> If the anx7625 is used just to route all lanes from 1 usb-c-connector (i.e
> the USB+DP case), a mode-switch wouldn't be of much use, since one
> would also route the CC lines to the built-in PD controller; so it will
> already have knowledge of what mode the switch is in.
>
> The mode-switch is likely only relevant for this hardware configuration(
> it's "DP only" in the sense that the USB pins to the SoC never go anywhere).
> One only has 2 SS lanes each (from each usb-c-connector).
>
> Since there is no CC-line, the anx7625 needs to know which one has DP
> enabled on it.

Can the CC line be "captured" and not actually sent to the anx7625? I
imagine if that is possible, maybe the CC lines would go to some
micro-controller or something that did more typec management things and
then the anx7625 driver would need to do software control of the mode
and orientation control.