Re: [PATCH] pinctrl: intel: save HOSTSW_OWN register over suspend/resume

[Daniel Drake <drake@endlessm.com>]

Hi Mika,

Digging up this old thread again...

On Tue, Nov 21, 2017 at 8:13 PM Mika Westerberg
<mika.westerberg@linux.intel.com> wrote:
>
> On Tue, Nov 21, 2017 at 07:54:26PM +0800, Chris Chiu wrote:
> > Yup, I checked the value of the corresponded pin. It shows following before
> > suspend
> > pin 18 (GPIO_18) GPIO 0x40800102 0x00024075
> >
> > Then after resume
> > pin 18 (GPIO_18) GPIO 0x40800102 0x00024075 [ACPI]
>
> OK, so ownership is changed to ACPI.
>
> > What else register do you suggest me to compare? The PADCFG2 is invalid
>
> It's fine APL does not have PADCFG2.
>
> Hmm, I don't understand how this can work in Windows either. The Windows
> people told me that they don't save and restore anything else than
> padcfg registers + ie. If the ownership is changed to ACPI it means you
> don't get interrupts anymore (only GPEs) and that applies to Windows as
> well.

In the mails after the one quoted above, we reported back to you that
the new BIOS from Asus solved the issue.

However, during the time that has followed, we have had numerous user
reports from Asus E403NA, X540NA, and X541NA laptops (basically the
same models that we originally discussed) where the touchpad stops
working after suspend/resume, even with the latest BIOS. We managed to
get an affected E403NA unit in-hands again, and confirmed that
HOSTSW_OWN was being lost like we had observed before.

Unfortunately as this was a customer laptop we had to return it
immediately, before we could investigate further. We don't have access
to any more units since they are old models now.

However I'm wondering if you have any other ideas or if you think
something like our workaround patch might be acceptable under these
circumstances:
https://github.com/endlessm/linux/commit/f391452299f62a3d0cbe5333be90f69e9895d8ff

Thanks
Daniel