RE: [char-misc for 4.10-rc4 V2] mei: bus: enable OS version only for SPT and newer

From: Winkler, Tomas
Date: Wed Jan 11 2017 - 11:14:10 EST



> On 01/11/17 15:12, Winkler, Tomas wrote:
>
> >>> On 01/11/17 10:24, Winkler, Tomas wrote:
> >>>>>
> >>>>> On Wed, Jan 11, 2017 at 01:27:21AM +0200, Tomas Winkler wrote:
> >>>>>> On older platforms the command should be just ignored by the
> >>>>>> firmware but some older platforms misbehave so it's safer to send
> >>>>>> the command only if required.
> >>>>>
> >>>>> Thanks! This fixes suspend-to-ram for me (on a Thinkpad x201s).
> >>>>
> >>>> What about Dell XPS13?
> >>>
> >>> With Linus' master branch from today, and Greg's char-misc-linus
> >>> merged
> >>> (Merge: 807b93e995d1 546cf3ef9c92), the regression is still there.
> >>
> >> Hmm, this should work on KBL....
> >>
> >>> I am now building a Linux kernel image with the two commits touching
> >>> `bus- fixup.c` reverted.
> >>
> >> Thanks for the effort.
> >>
> >>> Do you want me to open a separate bug report for that, or continue
> >>> debugging in the existing report [1], which is currently marked as resolved?
> >>
> >> Let's get some more data, shouldn't take long time.
> >>>
> >>> Do you have Kaby Lake devices sitting around for testing?
> >>
> >> We will of course try to reproduce the issue locally.
> >
> > Paul, currently we cannot reproduce this issue on Kaby Lake platforms
> > on our side,
>
> It looks like it's a different issue. Reverting the two commits touching `bus-
> fixup.c`, did not help.
>
> > we would be great for more debug data from your side.
> > You can get more info by enabling mode debug logs
> >
> > echo -n 'module mei +lfp' > /sys/kernel/debug/dynamic_debug/control
> > echo -n 'module mei_me +lfp' > /sys/kernel/debug/dynamic_debug/control
>
> I am currently bisecting to find the culprit. 13 steps will take some time
> though.
>
> Tomas, I believe Intel's "ACPI department" got access to a Dell XPS13.
>
>
> Kind regards,
>
Thanks for updated, really appreciated your engagement. I believe this closes the issue from MEI side.
I'll be watching this ACPI issue as well.
Thanks
Tomas