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 0418329CE9 for ; Tue, 21 Jul 2026 18:27:23 +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=1784658444; cv=none; b=tvLTCHsL8EHMvCFPptaB4zWXZuDleHmXLdhyyYy58k1W2qUUnhH8ZXetkOAmavovgjzLYzGoAUoiTmFfKJbOtSl0mQF4eptoMOTKrAD/YQVzUJcJuRlbHC2BMXkWjCyNJvUZbN9JhMdPji434d0CXBb9eORO+XQdCm8lqXBVJmM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784658444; c=relaxed/simple; bh=US/bH4L3jJS/MQlnEuBy0Ymf0tFgP9oMc95ReTDJtV0=; h=From:To:Subject:Date:Message-ID:Content-Type:MIME-Version; b=N1JkMQ/8SfbS7EMNc760IK6RnXTVjnxZh8EXzDKm6ZzcyEkmQqmwz5QLRjnskXs9dyFmJEWgO2BD/OGINcsHKwvWqSfNcHaE9nHhBC3jWvEAFpnrwUijxjhZfk39gHLmT6qL+UvHoWBw4NGusZZHbmtnX/ge/e2J/XcStfTCCqg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=tO3bF62o; 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="tO3bF62o" Received: by smtp.kernel.org (Postfix) with ESMTPS id B08C4C2BCF7 for ; Tue, 21 Jul 2026 18:27:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1784658443; bh=US/bH4L3jJS/MQlnEuBy0Ymf0tFgP9oMc95ReTDJtV0=; h=From:To:Subject:Date:From; b=tO3bF62oHOGAiZchjgH0R7PAMSkNaOpwQJlCIQFm7Ecj5+QWPz04YnDLMIjSdiS8I BLg/QqN619CqLcTi2ZBR9tHWZkFcPexkKRAOMV8/3V4o/5Z/AxqYtT0NWr87eITvXt t4zIpdmygsSHJ1frJNlcqfCDCcbR11Slh0tK2qwMQfOqPr18g90Oss7AF7X58F7lg7 IMBpv+ARaRJFBfZo4zg/FWtz1kr1RxDdz3GNYaumxxeKskrQIFLS5cqtjXs+T/0qoK PU9ozSv5umVt1l0awVcX0ESnfoR9ESmUqvLuL/yeZWT1DOgbje+fmX4QAIYIz48+6V vNiqrM6Eqsg/A== Received: by aws-us-west-2-korg-bugzilla-1.web.codeaurora.org (Postfix, from userid 48) id 8CFB5C3279F; Tue, 21 Jul 2026 18:27:23 +0000 (UTC) From: bugzilla-daemon@kernel.org To: linux-usb@vger.kernel.org Subject: [Bug 221776] New: HP OmniBook X Flip - Broken UCSI firmware / Slow charging Date: Tue, 21 Jul 2026 18:27:23 +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: daviddelsol1998@gmail.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=3D221776 Bug ID: 221776 Summary: HP OmniBook X Flip - Broken UCSI firmware / Slow charging Product: Drivers Version: 2.5 Hardware: All OS: Linux Status: NEW Severity: normal Priority: P3 Component: USB Assignee: drivers_usb@kernel-bugs.kernel.org Reporter: daviddelsol1998@gmail.com Regression: No The HP OmniBook X Flip has a non-compliant UCSI firmware in its Embedded Controller. The EC accepts only read-only UCSI commands (GET_VERSION, GET_CONNECTOR_STATUS) but rejects all control/write commands (SET_NOTIFICATION_ENABLE, PPM_RESET, CONNECTOR_RESET, and any _DSM WRITE function calls). When the ucsi_acpi driver loads and attempts to use UCSI for USB PD negotiation, the EC state eventually becomes corrupted. This causes USB PD to drop from 20V (65W) to 5V (~2W to battery), severely limiting charging speed. The corruption persists across reboots and even warm reboots. Only a full EC reset (shutdown + unplug + 30s power drain + replug) restores normal PD negotiation. WORKAROUND: Blacklist ucsi_acpi (module_blacklist=3Ducsi_acpi on kernel cmdline). Without UCSI, Linux doesn't talk to the broken EC firmware, the charger negotiates PD directly, and charging works at 25-30W (expected "normal speed" with system running). REPRODUCE: 1. Boot with ucsi_acpi loaded (default) 2. Plug in the 65W USB-C PD charger 3. Wait 30-60 seconds 4. Observe charging current drop from ~25W to ~2W via /sys/class/power_supply/BAT0/power_now 5. After that, pd voltage locked at 5V (visible via /sys/class/typec/port0/pd_data) ROOT CAUSE: The EC UCSI firmware at ACPI path PNP0CA0 implements the _DSM (UCSI DSM UUID: 6f8398c2-7ca4-11e4-ad36-631042b5008f) but returns error for function 1 (WRITE). The ucsi_acpi driver's ucsi_acpi_async_control() calls _DSM WRITE to send UCSI commands to the EC mailbox, but these writes either fail or silently corrupt the EC's internal state. DIAGNOSTIC EVIDENCE: - acpi_call test: _DSM function 1 (WRITE) fails with error - UCSI debugfs GET_CONNECTOR_STATUS succeeds - UCSI debugfs PPM_RESET/CONNECTOR_RESET returns EOPNOTSUPP - After ucsi_acpi loads, /sys/class/typec/port0/power_role shows "sink" even though charger is capable of sourcing - After corruption, /sys/kernel/debug/usb/ucsi/*/status shows PD contract at 5V/3A instead of 20V/3.25A - Blacklisting ucsi_acpi + EC reset restores proper PD negotiation PROPOSED FIX: Add DMI quirk to ucsi_acpi.c to skip the driver on this hardware: --- a/drivers/usb/typec/ucsi/ucsi_acpi.c +++ b/drivers/usb/typec/ucsi/ucsi_acpi.c @@ -79,6 +79,17 @@ static const struct dmi_system_id ucsi_acpi_quirks[] =3D= { DMI_MATCH(DMI_PRODUCT_NAME, "90Q"), }, .driver_data =3D (void *)&ucsi_gram_ops, + }, + { + /* + * HP OmniBook X Flip has broken UCSI firmware that rejects= all + * control commands (SET_NOTIFICATION_ENABLE, PPM_RESET, et= c.). + * Skip UCSI to avoid corrupting EC state and losing PD negotiation. + */ + .matches =3D { + DMI_MATCH(DMI_SYS_VENDOR, "HP"), + DMI_MATCH(DMI_PRODUCT_NAME, "HP OmniBook X Flip Lap= top 16-ar0xxx"), + }, }, { } }; @@ -213,6 +224,11 @@ static int ucsi_acpi_probe(struct platform_device *pde= v) ua->dev =3D &pdev->dev; id =3D dmi_first_match(ucsi_acpi_quirks); + if (id && !id->driver_data) { + dev_info(&pdev->dev, "broken UCSI firmware, skipping driver\n"); + return -ENODEV; + } if (id) ops =3D id->driver_data; --=20 You may reply to this email to add a comment. 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