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

[Greg KH <greg@kroah.com>]

On Tue, Jul 21, 2026 at 06:30:50PM +0000, bugzilla-daemon@kernel.org wrote:
> 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>

Please send this to the linux-usb mailing list, with a proper name, and
we will be glad to review it there.

thanks,

greg k-h