From mboxrd@z Thu Jan 1 00:00:00 1970 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 4BDCE36F40A for ; Wed, 25 Feb 2026 23:03:16 +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=1772060596; cv=none; b=c2yVeO53FpnGSOOMTqNl1wQOgDg8PjTnH30+7KR0qSQwGUULZ9QMeo+vbpayhc+y+xH6y4nj9JAfT1C3z10aaqjlt7I5RKI5c+ZIA4MIjZUZd5BanczXI70He1wWZLMF10xdB6ddNJcoAMA41/xKE8ylU4lrdDKPIt3moCwqJmw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772060596; c=relaxed/simple; bh=o5n/8BHSPhocJAqu5vlmj7hY0mJzh+/WfyTOqEAoVWg=; h=From:To:Subject:Date:Message-ID:Content-Type:MIME-Version; b=jhJxbnW/ufMYUJVxP8EREm9yCDIPzt5wPTvxz6C83Cd81xtKUfb6k/trxUiwYtwuUH2AXMjKj709ifmlVKKYv0INejwopXhFvLU8+rP5cPDUR4D8ekK+TE2XIC9Nh2pMfV7d1j1phZxJWo5mBanuJ/+s7qCqP/R2jfA1HLFHEYk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=t6rsCwWv; 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="t6rsCwWv" Received: by smtp.kernel.org (Postfix) with ESMTPS id D1448C116D0 for ; Wed, 25 Feb 2026 23:03:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772060595; bh=o5n/8BHSPhocJAqu5vlmj7hY0mJzh+/WfyTOqEAoVWg=; h=From:To:Subject:Date:From; b=t6rsCwWvf8C+A854JmC2OOWsIrsTKofcjn7xj6l0vXq9yjJkZSudMsZslfdlCTPtj b0tgi5k5gAGpZKC+VB3y6USI4U337pcMhE4AFgG2YUC8WUR8+FQ6e0mPsEZS+zrU5+ T43LMRDqezQc8flY1YKFzVdJ8alJWT58MCEPPmVWaPf6IuGWo2ZZ1SmG59YrFl6AgF cB/Rqheea5b1RqmP4DzVkf316z+/VO+oZUnH+1Ndq5kL7WIbvvo1pwZZ4N7VPQ09Td 3PM4sZNMoUmK3NZ3koa3Igj+/5sITE8mRZHmSVfGnX60aggaY0dwIJe5lRZO+rR6Hn /xDX2CNu6RZxQ== Received: by aws-us-west-2-korg-bugzilla-1.web.codeaurora.org (Postfix, from userid 48) id BFABFC3279F; Wed, 25 Feb 2026 23:03:15 +0000 (UTC) From: bugzilla-daemon@kernel.org To: linux-usb@vger.kernel.org Subject: [Bug 221142] New: ucsi_acpi actively breaks USB-C PD charging on Lenovo Legion Pro 7 (Arrow Lake) Date: Wed, 25 Feb 2026 23:03:15 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: AssignedTo drivers_usb@kernel-bugs.kernel.org X-Bugzilla-Product: Drivers X-Bugzilla-Component: USB X-Bugzilla-Version: 2.5 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: alex@alstergee.com X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: drivers_usb@kernel-bugs.kernel.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter cf_regression Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 https://bugzilla.kernel.org/show_bug.cgi?id=3D221142 Bug ID: 221142 Summary: ucsi_acpi actively breaks USB-C PD charging on Lenovo Legion Pro 7 (Arrow Lake) Product: Drivers Version: 2.5 Hardware: Intel OS: Linux Status: NEW Severity: normal Priority: P3 Component: USB Assignee: drivers_usb@kernel-bugs.kernel.org Reporter: alex@alstergee.com Regression: No The ucsi_acpi driver actively interferes with USB-C Power Delivery negotiat= ion on the Lenovo Legion Pro 7 16IAX10H (83F5, Intel Arrow Lake, BIOS Q7CN44WW). Blacklisting ucsi_acpi completely fixes the issue =E2=80=94 the EC's PD con= troller negotiates correctly on its own. SYSTEM: - Lenovo Legion Pro 7 16IAX10H (product ID 83F5) - Intel Core Ultra 9 275HX (Arrow Lake) - BIOS Q7CN44WW (Nov 2025, latest available) - Kernel 6.18.0 SYMPTOMS WITH ucsi_acpi LOADED: - USB-C PD chargers connect briefly then drop after 1-3 minutes - voltage_now always reads 0 in /sys/class/power_supply/ucsi-source-psy-*/ - usb_power_delivery_revision on partner reports 0.0 (should be 3.0) - No source-capabilities PDO objects ever appear in sysfs - GET_PDOS appears to return empty data from the EC - GET_CONNECTOR_STATUS returns incomplete RDO - Some chargers never establish a PD contract at all (Shargeek 100W: only 1= .4W) - Failed PD negotiations wedge the UCSI PPM =E2=80=94 requires full reboot = to recover - ACPI workqueue warnings: "acpi_os_execute_deferred hogged CPU for >10000u= s" RESULTS WITH ucsi_acpi BLACKLISTED: - Shargeek 100W: 1.4W =E2=86=92 40-55W (full PD negotiation at proper volta= ge) - Anker 65W: 5W =E2=86=92 expected full power - Barrel jack 330W: unaffected (70W, bypasses USB-C) The EC's PD controller handles negotiation correctly without OS involvement. The ucsi_acpi driver queries the broken UCSI mailbox and interferes with wh= at would otherwise be a working PD contract. This is the same class of Lenovo EC firmware bug as: - ThinkPad T14 Gen 5: https://github.com/fwupd/firmware-lenovo/issues/521 (Lenovo internal ticket LO-4169 =E2=80=94 EC returns static/dummy RDO) - Framework Laptop 16: PDOs read as 0x00000000 despite successful PD negotiation RELATED KERNEL PATCHES: - Benson Leung, Dec 2025: Fix voltage_now/current_now for non-PD sources https://lkml.org/lkml/2025/12/8/912 - Benson Leung, Dec 2025: Fix voltage/current max for non-Fixed PDOs https://lkml.org/lkml/2025/12/8/913 (commit 6811e0a08bdc) (These fix reporting but don't address the EC returning empty PDO data) PROPOSED FIX: The kernel could add a quirk for Lenovo platforms where the UCSI PPM is kno= wn to return broken PDO data, either: 1. Skip GET_PDOS calls on affected platforms (let EC handle PD autonomously) 2. Add a module parameter to make ucsi_acpi passive/read-only 3. Detect empty GET_PDOS responses and back off instead of interfering WORKAROUND: echo "blacklist ucsi_acpi" > /etc/modprobe.d/blacklist-ucsi.conf STEPS TO REPRODUCE: 1. Boot Lenovo Legion Pro 7 16IAX10H with kernel 6.18 2. Plug in any USB-C PD charger 3. Observe charging starts briefly then drops (BAT0/status =E2=86=92 Discha= rging) 4. Check /sys/class/power_supply/ucsi-source-psy-*/voltage_now =E2=86=92 al= ways 0 5. Blacklist ucsi_acpi, reboot, plug charger =E2=86=92 charges at full PD p= ower --=20 You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.=