Re: [PATCH] ACPI: OSI: Enable _OSI("Windows 2022") on HP OmniBook X Flip 16-ar0xxx

[Mario Limonciello <mario.limonciello@amd.com>]

On 8/11/26 12:48, David Del Sol wrote:
> Hi all,
> 
> This fixes slow battery charging on the 2025 HP OmniBook X Flip (AMD Ryzen
> AI 5 340, DMI board 8DA8): with a 65 W charger plugged in, the battery
> charges at only ~0.2 W on Linux instead of the ~30 W Windows gets.
> 
> The EC firmware only enables normal charging when the OS claims
> _OSI("Windows 2022"), and the DSDT/SSDT only check up to that string.
> Linux's default claimed OSI strings stop short of it, so the fast-charging
> branch never runs. Adding acpi_osi=! acpi_osi="Windows 2022" to the kernel
> cmdline restores 31-33 W - verified across multiple charge cycles on
> kernels 7.1.6 and 6.18.42-LTS.
> 
> I checked with HP first: they declined in writing (warranty case
> #5163282638, supervisor email 2026-08-10), saying the firmware is
> "specifically manufactured and optimized for the Windows operating system"
> and not supported for other OSes. A kernel-side quirk is therefore the
> only fix path.
> 
> The patch claims _OSI("Windows 2022") via acpi_osi_setup() with a DMI
> match scoped to board 8DA8 (same mechanism as dmi_enable_osi_linux), so
> no other platform is affected. Full evidence - DSDT/SSDT strings, EC RAM
> dumps, measurement logs - is on the bugzilla report below; happy to add
> sibling boards as owners confirm.
> 
> Thanks for looking,
> David
> 
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=221866 <https:// 
> bugzilla.kernel.org/show_bug.cgi?id=221866>

Are you sure about your proposed root cause?  It has been enabled a very 
long time.

https://git.kernel.org/torvalds/c/dd067afe3f8cb