From nobody Thu Apr 9 07:12:46 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B260C4508F2; Tue, 10 Mar 2026 09:02:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773133341; cv=none; b=hfxx4p7oogXBNFDL5sPHOKjyGumNAiEgeCqIZB4cldsVbXJrX9zZeNFoQcT9dJ2y1pz8JrN4SEZIf0mHBZCNqKO8ApdNLVRWhu1+TPq1fYIY608EK7vQzrOhM91KpsekZd2XsfeTODLDj1DKdPwd0h7o7e3+4yFRO6SECs7zgDo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773133341; c=relaxed/simple; bh=oTCcKoiBg4Ndl4dFHqHelPZE7Fdxyv/0WoL9zpscZ78=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=PihLoPU7Y7Qr0MngTIUIzO1IUunC0htpYSOfFJruJffxRMgMROtgA031yyr8Q63SqSKf5wapxLNIeklWFDtzXQDuu8eMl4TArXNtz+b9IsSl/pLYKv5aAZaSxpiCnuml2m25Y6anAy400QQgj85lO6NKtfixt/Lcz2sKulUVacg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=W8P//Xyv; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="W8P//Xyv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 93F85C2BC9E; Tue, 10 Mar 2026 09:02:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773133341; bh=oTCcKoiBg4Ndl4dFHqHelPZE7Fdxyv/0WoL9zpscZ78=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=W8P//Xyvp1IQk7GVRhDLfxjC/otAxwJJOB8efJ6W9eZL0kf2o/Hupgp/cy6lo8zAv 5NE0FgWVbiFJZzJ4yMvP7st/cBtM50nk5bSK07iG3e2euVHoEwBEEO3zi/WnmKUPKD K9Tv9NGrAiFC//58rNfmBZozOIoF8PodEUz/2OjB5WtGPOfPPXkFK6tGBaCQQHFuiU uZpU/ixVXzQkrhJ0bKEODQtuPvMizeZWpTB+lwFOkswdlsHefJCFgX+ftlsEMEakwh ccNhlR4KkSCUKiRU3KCMgljUmfEMBZeGq9Le2smi4+jAcPBMZcNTN1oqe7rzrL7IRp hS1Pwlw5azf4g== From: Sasha Levin To: patches@lists.linux.dev, stable@vger.kernel.org Cc: Leif Skunberg , Hans de Goede , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= , Sasha Levin , alexhung@gmail.com, hansg@kernel.org, platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH AUTOSEL 6.19-5.10] platform/x86: intel-hid: Enable 5-button array on ThinkPad X1 Fold 16 Gen 1 Date: Tue, 10 Mar 2026 05:01:24 -0400 Message-ID: <20260310090145.2709021-24-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260310090145.2709021-1-sashal@kernel.org> References: <20260310090145.2709021-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.19.6 Content-Transfer-Encoding: quoted-printable From: Leif Skunberg [ Upstream commit b38d478dad79e61e8a65931021bdfd7a71741212 ] The Lenovo ThinkPad X1 Fold 16 Gen 1 has physical volume up/down buttons that are handled through the intel-hid 5-button array interface. The firmware does not advertise 5-button array support via HEBC, so the driver relies on a DMI allowlist to enable it. Add the ThinkPad X1 Fold 16 Gen 1 to the button_array_table so the volume buttons work out of the box. Signed-off-by: Leif Skunberg Reviewed-by: Hans de Goede Link: https://patch.msgid.link/20260210085625.34380-1-diamondback@cohunt.app Reviewed-by: Ilpo J=C3=A4rvinen Signed-off-by: Ilpo J=C3=A4rvinen Signed-off-by: Sasha Levin --- LLM Generated explanations, may be completely bogus: ## Analysis ### What the commit does This commit adds a single DMI table entry for the Lenovo ThinkPad X1 Fold 16 Gen 1 to the `button_array_table` in `drivers/platform/x86/intel/hid.c`. This enables the intel-hid 5-button array interface for physical volume up/down buttons on this specific laptop, whose firmware does not advertise 5-button array support via the HEBC ACPI method. ### Classification: Hardware Quirk/Workaround This is a textbook DMI allowlist addition =E2=80=94 one of the explicitly allowed exception categories for stable backporting. The pattern is identical to the existing entries for HP Spectre x2, ThinkPad X1 Tablet Gen 1/2, Microsoft Surface Go 3/4, etc. ### Stable kernel criteria assessment - **Obviously correct and tested**: Yes. The 7-line addition follows the exact same `DMI_MATCH(DMI_SYS_VENDOR, "LENOVO")` + `DMI_MATCH(DMI_PRODUCT_FAMILY, ...)` pattern used by the two existing Lenovo entries directly above it. - **Fixes a real bug**: Yes. Volume buttons are non-functional without this entry because firmware doesn't advertise the capability. - **Small and contained**: Yes. 7 lines added to a single DMI table in one file. No logic changes whatsoever. - **No new features**: Correct. This enables an existing driver interface on specific hardware =E2=80=94 an allowed exception. - **No dependencies**: The `button_array_table` and its usage have been in the driver for years. No prerequisite commits needed. ### Risk assessment **Extremely low risk.** DMI matching is device-specific =E2=80=94 this entry only activates on systems where `DMI_SYS_VENDOR =3D=3D "LENOVO"` AND `DMI_PRODUCT_FAMILY =3D=3D "ThinkPad X1 Fold 16 Gen 1"`. It cannot affect any other hardware. The worst-case scenario on a misidentified system would be the 5-button array being enabled unnecessarily, which is benign. ### Review quality The patch has two `Reviewed-by` tags from Hans de Goede (former platform/x86 co-maintainer) and Ilpo J=C3=A4rvinen (current platform/x86 maintainer who also committed it). This is strong endorsement. ### Verification - Verified the diff adds only a DMI table entry with no logic changes =E2= =80=94 confirmed by reading the patch. - Verified the new entry follows the identical pattern of existing entries (DMI_SYS_VENDOR + DMI_PRODUCT_FAMILY matching) =E2=80=94 confirmed from the surrounding context in the diff. - Verified this is a DMI allowlist (not a blocklist) used to enable 5-button array support =E2=80=94 confirmed from the commit message and ta= ble name `button_array_table`. - Verified reviewers Hans de Goede and Ilpo J=C3=A4rvinen are established platform/x86 maintainers =E2=80=94 this is well-known in the kernel commu= nity. - The file `drivers/platform/x86/intel/hid.c` and the `button_array_table` have existed in the kernel for years, so this applies to all active stable trees. ### Conclusion This is a minimal, zero-risk hardware quirk addition that makes volume buttons work on a specific Lenovo laptop. It meets all stable kernel criteria and falls into the explicitly allowed "hardware quirks/workarounds" category. Two maintainer reviews provide confidence in correctness. **YES** drivers/platform/x86/intel/hid.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/platform/x86/intel/hid.c b/drivers/platform/x86/intel/= hid.c index 5b475a09645a3..f2b309f6e458a 100644 --- a/drivers/platform/x86/intel/hid.c +++ b/drivers/platform/x86/intel/hid.c @@ -135,6 +135,13 @@ static const struct dmi_system_id button_array_table[]= =3D { DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Tablet Gen 2"), }, }, + { + .ident =3D "Lenovo ThinkPad X1 Fold 16 Gen 1", + .matches =3D { + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), + DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Fold 16 Gen 1"), + }, + }, { .ident =3D "Microsoft Surface Go 3", .matches =3D { --=20 2.51.0