[Bug 221776] HP OmniBook X Flip - Broken UCSI firmware / Slow charging

[bugzilla-daemon@kernel.org]

https://bugzilla.kernel.org/show_bug.cgi?id=221776

--- Comment #1 from David Del Sol (daviddelsol1998@gmail.com) ---
From: David <david@david-desktop>
Date: Tue, 21 Jul 2026 11:30:00 -0500
Subject: [PATCH] usb: typec: ucsi: Skip UCSI on HP OmniBook X Flip (broken EC
firmware)

The HP OmniBook X Flip (Ryzen AI 5 340) has a non-compliant UCSI
firmware in the embedded controller.  The EC rejects all write/control
UCSI commands (SET_NOTIFICATION_ENABLE, PPM_RESET, etc.) while
accepting only read-only commands (GET_*). This causes the UCSI
subsystem to eventually corrupt the EC state, resulting in USB PD
negotiation falling back to 5V (only ~2W charging instead of 65W).

Add a DMI-based quirk to prevent the ucsi_acpi driver from binding
to this hardware.  Use NULL driver_data to signal "broken firmware,
skip UCSI entirely".

The user-visible symptom is that with a 65W USB-C PD charger, the
battery charges at 2W instead of 25-30W after the first UCSI command
exchange.  The workaround (removing this driver) has been verified
on multiple charge cycles.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=XXXXX
Signed-off-by: David <david@david-desktop>
---
diff --git a/drivers/usb/typec/ucsi/ucsi_acpi.c
b/drivers/usb/typec/ucsi/ucsi_acpi.c
index 5b7d00907e39..c9bdeb110974 100644
--- 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[] = {
                        DMI_MATCH(DMI_PRODUCT_NAME, "90Q"),
                },
                .driver_data = (void *)&ucsi_gram_ops,
+       },
+       {
+               /*
+                * HP OmniBook X Flip has broken UCSI firmware that rejects all
+                * control commands (SET_NOTIFICATION_ENABLE, PPM_RESET, etc.).
+                * Skip UCSI to avoid corrupting EC state and losing PD
negotiation.
+                */
+               .matches = {
+                       DMI_MATCH(DMI_SYS_VENDOR, "HP"),
+                       DMI_MATCH(DMI_PRODUCT_NAME, "HP OmniBook X Flip Laptop
16-ar0xxx"),
+               },
        },
        { }
 };
@@ -213,6 +224,11 @@ static int ucsi_acpi_probe(struct platform_device *pdev)
        ua->dev = &pdev->dev;

        id = 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 = id->driver_data;

-- 
You may reply to this email to add a comment.

You are receiving this mail because:
You are watching the assignee of the bug.