[SRU] [Artful/linux-oem] [PATCH 0/1] Fix an issue that when system in S3, USB keyboard can't wake up the system.

[Kai-Heng Feng]

Kai-Heng Feng <kai.heng.feng at canonical.com> wrote:

> BugLink: https://bugs.launchpad.net/bugs/1759511

I forgot to write the SRU justification for the cover-letter, I'll put them  
here now.
I can send a V2 patch if it's not good enough.

[Impact]
xHC stays at D0 when system is in S3. Unfortunately D0 can't generate PME#  
wakeup event, so USB device can't wake the system.

[Test]
Intel NUC can't be waken up by USB keyboard when the system is in S3.
With the patch, USB keyboard can wake up the system.

[Fix]
ACPI spec is not clear when both _S3D and _S3W are missing. Evidently  
device can work correctly in D3 when both of them are missing, so we should  
relax the check.

[Regression Potential]
Low.
The issue starts appearing from Gemini Lake, older generation hardware  
shouldn't get affected.

>
> Daniel Drake (1):
>   ACPI / PM: Allow deeper wakeup power states with no _SxD nor _SxW
>
>  drivers/acpi/device_pm.c | 11 ++++++++++-
>  1 file changed, 10 insertions(+), 1 deletion(-)
>
> -- 
> 2.15.1
>
>
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