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Date:   Wed, 26 Jan 2022 23:08:14 +0000
From:   Prashant Malani <pmalani@chromium.org>
To:     Alyssa Ross <hi@alyssa.is>
Cc:     linux-kernel@vger.kernel.org, Tzung-Bi Shih <tzungbi@google.com>,
        Benson Leung <bleung@chromium.org>,
        Enric Balletbo i Serra <enric.balletbo@collabora.com>,
        Guenter Roeck <groeck@chromium.org>,
        Heikki Krogerus <heikki.krogerus@linux.intel.com>
Subject: Re: [PATCH v2] platform/chrome: cros_ec_typec: Check for EC device
Message-ID: <YfHUXtJPU77wtCPb@chromium.org>
References: <20220126190219.3095419-1-pmalani@chromium.org>
 <20220126230411.nn2illij4wbpdm4q@eve>
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Hi Alyssa,

On Jan 26 23:04, Alyssa Ross wrote:
> On Wed, Jan 26, 2022 at 07:02:20PM +0000, Prashant Malani wrote:
> > The Type C ACPI device on older Chromebooks is not generated correctly
> > (since their EC firmware doesn't support the new commands required). In
> > such cases, the crafted ACPI device doesn't have an EC parent, and it is
> > therefore not useful (it shouldn't be generated in the first place since
> > the EC firmware doesn't support any of the Type C commands).
> >
> > To handle devices which use these older firmware revisions, check for
> > the parent EC device handle, and fail the probe if it's not found.
> >
> > Fixes: fdc6b21e2444 ("platform/chrome: Add Type C connector class driver")
> > Reported-by: Alyssa Ross <hi@alyssa.is>
> > Reviewed-by: Tzung-Bi Shih <tzungbi@google.com>
> > Signed-off-by: Prashant Malani <pmalani@chromium.org>
> > ---
> > Hi Alyssa, could you kindly test this with your existing setup? Thanks!
> 
> Hi Prashant, I'm happy to test, but I'm on vacation until the end of the
> week so probably won't get a chance before Monday.

No worries, whenever you get the chance is fine.

> 
> I'm guessing I should be testing with latest upstream coreboot (now that
> your fix there has been applied)?

You should use the coreboot with which you discovered the crash, so the
one which *doesn't* contain the fix.

Thanks again!

-Prashant