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From:   Mario Limonciello <mario.limonciello@amd.com>
To:     <linux-kernel@vger.kernel.org>, <linux-acpi@vger.kernel.org>,
        <rafael@kernel.org>, Len Brown <lenb@kernel.org>
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        <hdegoede@redhat.com>, <ddadap@nvidia.com>,
        <kai.heng.feng@canonical.com>, <Dell.Client.Kernel@dell.com>,
        Mario Limonciello <mario.limonciello@amd.com>
Subject: [RFC 0/2]  Stop the abuse of Linux-* _OSI strings
Date:   Fri, 19 Aug 2022 09:25:17 -0500
Message-ID: <20220819142519.5684-1-mario.limonciello@amd.com>
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3 _OSI strings were introduced in recent years that were intended
to workaround very specific problems found on specific systems.

The idea was supposed to be that these quirks were only used on
those systems, but this proved to be a bad assumption.  I've found
at least one system in the wild where the vendor using the _OSI
string doesn't match the _OSI string and the neither does the use.

So this brings a good time to review keeping those strings in the kernel.
There are 3 strings that were introduced:

Linux-Dell-Video
-> Intended for systems with NVIDIA cards that didn't support RTD3
Linux-Lenovo-NV-HDMI-Audio
-> Intended for powering on NVIDIA HDMI device
Linux-HPI-Hybrid-Graphics
-> Intended for changing dGPU output

AFAIK the first string is no longer relevant as nouveau now supports
RTD3.  If that's wrong, this can be changed for the series.

The second two strings appear to be non-scalable workarounds.  For
accomplishing these tasks, registers can be written from kernel drivers
or custom ASL can be put behind a _DSM.  By forcing either of these two
solutions it will better let the Linux kernel control the behavior.

Based on the above this series drops the first string and marks the second
two strings to only apply to older systems.

Link: https://lore.kernel.org/all/54add026bb6f45fd94a2dc2bae4adf9f@AUSX13MPC101.AMER.DELL.COM/T/

Mario Limonciello (2):
  ACPI: OSI: Remove Linux-Dell-Video _OSI string
  ACPI: OSI: Deprecate some abused _OSI strings

 Documentation/firmware-guide/acpi/osi.rst | 24 ++++++++----------
 drivers/acpi/osi.c                        | 31 ++++++++++++-----------
 2 files changed, 26 insertions(+), 29 deletions(-)

-- 
2.34.1