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From: Ben Walsh <ben@jubnut.com>
To: Dustin Howett <dustin@howett.net>
Cc: Tzung-Bi Shih <tzungbi@kernel.org>, Benson Leung <bleung@chromium.org>,
 Guenter Roeck <groeck@chromium.org>, Kieran Levin <ktl@frame.work>, Thomas
 =?utf-8?Q?Wei=C3=9Fschuh?= <linux@weissschuh.net>, Mario Limonciello
 <mario.limonciello@amd.com>, chrome-platform@lists.linux.dev,
 linux-kernel@vger.kernel.org
Subject: Re: [PATCH 5/6] platform/chrome: cros_ec_lpc: Correct ACPI name for
 Framework Laptop
In-Reply-To: <CA+BfgNL7RGWuFK-M=Cpt8nLfroK+Xpqtzs4nQ1Bwnv6iiVd5nQ@mail.gmail.com>
References: <20240515055631.5775-1-ben@jubnut.com>
 <20240515055631.5775-6-ben@jubnut.com> <ZkscFnmHeWWma7Nb@google.com>
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Date: Fri, 24 May 2024 19:45:41 +0100
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Dustin Howett <dustin@howett.net> writes:

> On Fri, May 24, 2024 at 1:35=E2=80=AFPM Ben Walsh <ben@jubnut.com> wrote:
>>
>> I could add a new quirk which provides an alternative ACPI match table
>> to be used instead of the default. In the default case the match_table
>> will contain only "GOOG0004" as before. But in the Framework EC case the
>> match table will be "PNP0C09".
>
> My biggest concern with putting PNP0C09 in the direct match table is
> that it would cause cros_ec_lpcs to be loaded for *all* devices with
> an ACPI-compatible embedded controller; it would likely print an error
> and bail out early on, but it would still be unnecessary on 99% of
> platforms.

That's exactly what we're talking about: how to *avoid* putting PNP0C09
in the match table.

My original idea was to put it in the match table, but only allow a
match to proceed if Framework EC is detected by DMI.

My new idea is to not to put it in the match table *at all*, but to
provide a new match table if Framework EC is detected by DMI.