Re: [PATCH v2 5/5] Documentation/arch/x86/amd-debugging: Add section about delay_suspend

[Ilpo Järvinen]

On Sat, 9 May 2026, Daniel Gibson wrote:

> must be updated with the actual commit IDs when they are merged

Please write a proper changelog text.

Unfortunately, I cannot know the commit ID in advance as it depends on the 
commit content itself (git object hashing works that way).

> 
> Signed-off-by: Daniel Gibson <daniel@xxxxxxxxx>
> ---
>  Documentation/arch/x86/amd-debugging.rst | 25 ++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/Documentation/arch/x86/amd-debugging.rst b/Documentation/arch/x86/amd-debugging.rst
> index 3176a1240fee..3af7799cca1a 100644
> --- a/Documentation/arch/x86/amd-debugging.rst
> +++ b/Documentation/arch/x86/amd-debugging.rst
> @@ -249,6 +249,31 @@ state entry.
>  
>  `commit 40b8c14936bd2 ("drm/amd/display: Disable unneeded hpd interrupts during dm_init") <https://git.kernel.org/torvalds/c/40b8c14936bd2>`_
>  
> +Keyboard and Lid Switch stop working after resume
> +-------------------------------------------------
> +On various variants of the Lenovo IdeaPad Slim 3 with Barcelo and Rembrandt CPUs
> +the lid switch and keyboard, or at least the Fn/Multimedia keys, stopped working
> +after resume, until the next reboot.
> +
> +This was caused by buggy firmware having timing problems, the EC needed some idle
> +time right before the CPU cores are suspended, or it got into an inconsistent state.
> +
> +For laptops that are known to be affected this workaround is enabled
> +automatically, to test this workaround on other machines you can set the
> +``delay_suspend`` parameter of the ``amd_pmc`` module.
> +
> +If you need to set the ``delay_suspend`` parameter to fix your machine, please
> +report this at platform-driver-x86@xxxxxxxxxxxxxxx for it to be added to the
> +list of devices that need this workaround, so in future kernel versions it's
> +enabled automatically.
> +
> +Note that the current workaround isn't perfect: The problems can still happen
> +if resume is triggered by a timer (wakealarm).
> +
> +`commit TODO ("platform/x86/amd/pmc: Delay suspend for some Lenovo Laptops") <https://git.kernel.org/torvalds/c/TODO>`_
> +
> +`commit TODO ("platform/x86/amd/pmc: Add delay_suspend module parameter") <https://git.kernel.org/torvalds/c/TODO>`_
> +
>  Runtime power consumption issues
>  ================================
>  
> 

-- 
 i.