Re: [PATCH v2 2/2] platform/chrome: cros_ec_typec: Make sure the USB role switch has PLD

From: Prashant Malani
Date: Wed Feb 14 2024 - 13:15:08 EST


Hi Heikki,

On Wed, Feb 14, 2024 at 3:59 AM Heikki Krogerus
<heikki.krogerus@xxxxxxxxxxxxxxx> wrote:
>
> Hi Emilie,
>
> On Wed, Feb 14, 2024 at 12:04:22PM +0100, Emilie Roberts wrote:
> > My understanding is that this is related to the wiring spec and not
> > ChromeOS specific. It seems possible that OEMs making non-ChromeOS devices
> > may have this same issue. Or are we certain that only Chromebooks will ever
> > see this?
>
> Non-ChromeOS platforms do not have this issue.
>
> The issue is with the ACPI tables - the USB role switch ACPI device
> nodes don't have the _PLD object on these systems. Ideally this could
> be fixed there by simply adding the _PLD to those ACPI device objects,
> but I understood that that is not an option.
>
> But maybe I misunderstood... Can the ACPI tables on these platforms
> still be updated?

Since it's just a _PLD update to, it should be possible to do a "light" firmware
update on the relevant boards. Shyam/Emilie/Won, how practical is this?

I'd much prefer this to be fixed properly in the ACPI table than relying
on this quirk.

IAC, if we absolutely *have* to use this quirk:
Acked-by: Prashant Malani <pmalani@xxxxxxxxxxxx>

Thanks,