Re: [PATCH] Fix resume for ELAN2097 touchscreen.

[Jim Broadus]

Happy new year.

I think you might be right. I found some discussions about Dell
disabling S3 support in a recent bios due to a C-state bug.
I'll try to investigate a bit more this weekend.

Jim

On Fri, Feb 15, 2019 at 1:25 AM Kai-Heng Feng
<kai.heng.feng@xxxxxxxxxxxxx> wrote:
>
> Hi Jiri and James,
>
> > On Feb 15, 2019, at 15:35, Jiri Kosina <jikos@xxxxxxxxxx> wrote:
> >
> > On Thu, 14 Feb 2019, james broadus wrote:
> >
> >>> This should be fixed in hid.git#for-5.1/i2c-hid already by commit
> >>> 1475af255e18f. Could you please confirm that?
> >>>
> >>
> >> Hi Jiri. That change mutes the log messages, but I'm still counting
> >> around 35000 interrupts per second after resume and touch does not work.
> >> With the reset, the device works properly.
> >
> > Ah, I see. Should your patch then actually replace 1475af255e18f?
>
> Sorry for the late reply, was off because of Lunar new year.
>
> Commit 1475af255e18f is to silence the message when using the touchpad, so itâs different to this patch.
>
> Iâve seen similar bugs happens on new platforms that defaults S2Idle (Modern Standby), but user uses S3 instead.
> On those systems, S3 was never tested, so the BIOS doesnât cut the touchpadâs power off during S3, and the IRQ line wasnât getting properly reset.
>
> So if the platform defaults to S2Idle but user wants to use S3, this issue happens.
> If thatâs the case, maybe itâs better to report to the platform vendor.
>
> Kai-Heng
>
> >
> > Thanks,
> >
> > --
> > Jiri Kosina
> > SUSE Labs
> >
>