linux-kernel - Re: [PATCH 4/5] platform/x86: intel-vbtn: Also handle tablet-mode switch on "Detachable" and "Portable" chassis-types

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 5 May 2020 17:27:41 +0300
From:   Andy Shevchenko <andy.shevchenko@...il.com>
To:     Mario Limonciello <Mario.Limonciello@...l.com>
Cc:     Hans de Goede <hdegoede@...hat.com>,
        Darren Hart <dvhart@...radead.org>,
        Andy Shevchenko <andy@...radead.org>,
        ACPI Devel Maling List <linux-acpi@...r.kernel.org>,
        Platform Driver <platform-driver-x86@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 4/5] platform/x86: intel-vbtn: Also handle tablet-mode
 switch on "Detachable" and "Portable" chassis-types

On Tue, May 5, 2020 at 5:22 PM <Mario.Limonciello@...l.com> wrote:
>
> > -----Original Message-----
> > From: platform-driver-x86-owner@...r.kernel.org <platform-driver-x86-
> > owner@...r.kernel.org> On Behalf Of Hans de Goede
> > Sent: Tuesday, May 5, 2020 4:06 AM
> > To: Limonciello, Mario; dvhart@...radead.org; andy@...radead.org
> > Cc: linux-acpi@...r.kernel.org; platform-driver-x86@...r.kernel.org; linux-
> > kernel@...r.kernel.org
> > Subject: Re: [PATCH 4/5] platform/x86: intel-vbtn: Also handle tablet-mode
> > switch on "Detachable" and "Portable" chassis-types
> >
> >
> > [EXTERNAL EMAIL]
> >
> > Hi,
> >
> > On 5/4/20 5:37 PM, Mario.Limonciello@...l.com wrote:
> > >
> > >
> > >> -----Original Message-----
> > >> From: Hans de Goede <hdegoede@...hat.com>
> > >> Sent: Saturday, May 2, 2020 1:30 PM
> > >> To: Darren Hart; Andy Shevchenko; Limonciello, Mario
> > >> Cc: Hans de Goede; linux-acpi@...r.kernel.org; platform-driver-
> > >> x86@...r.kernel.org; linux-kernel@...r.kernel.org
> > >> Subject: [PATCH 4/5] platform/x86: intel-vbtn: Also handle tablet-mode
> > switch
> > >> on "Detachable" and "Portable" chassis-types
> > >>
> > >>
> > >> [EXTERNAL EMAIL]
> > >>
> > >> Commit de9647efeaa9 ("platform/x86: intel-vbtn: Only activate tablet mode
> > >> switch on 2-in-1's") added a DMI chassis-type check to avoid accidentally
> > >> reporting SW_TABLET_MODE = 1 to userspace on laptops.
> > >>
> > >> Some devices with a detachable keyboard and using the intel-vbnt (INT33D6)
> > >> interface to report if they are in tablet mode (keyboard detached) or not,
> > >> report 32 / "Detachable" as chassis-type, e.g. the HP Pavilion X2 series.
> > >>
> > >> Other devices with a detachable keyboard and using the intel-vbnt (INT33D6)
> > >> interface to report SW_TABLET_MODE, report 8 / "Portable" as chassis-type.
> > >> The Dell Venue 11 Pro 7130 is an example of this.
> > >>
> > >> Extend the DMI chassis-type check to also accept Portables and Detachables
> > >> so that the intel-vbtn driver will report SW_TABLET_MODE on these devices.
> > >>
> > >> Note the chassis-type check was originally added to avoid a false-positive
> > >> tablet-mode report on the Dell XPS 9360 laptop. To the best of my knowledge
> > >> that laptop is using a chassis-type of 9 / "Laptop", so after this commit
> > >> we still ignore the tablet-switch for that chassis-type.
> > >
> > > Yes that's correct.
> > >
> > >>
> > >> Fixes: de9647efeaa9 ("platform/x86: intel-vbtn: Only activate tablet mode
> > >> switch on 2-in-1's")
> > >> Signed-off-by: Hans de Goede <hdegoede@...hat.com>
> > >> ---
> > >> Looking at the Microsoft Windows documentation for tablet-mode reporting:
> > >> https://docs.microsoft.com/en-us/windows-hardware/drivers/gpiobtn/button-
> > >> implementation
> > >>
> > >> Then the presence of a tablet-mode switch is indicated by the presence
> > >> of a PNP0C60 compatible ACPI devices. There are 2 ways in which this device
> > >> can report the tablet-mode. 1. Directly providing a GpioInt resource inside
> > >> the PNP0C60 device, 2. Through injecting events from a Windows driver.
> > >>
> > >> It seems that the intel-vbtn / the INT33D6 ACPI device is the ACPI side
> > >> of Intel's generic solution for the case where the tablet-mode comes from
> > >> the embedded-controller and needs to be "injected".
> > >>
> > >> This all suggests that it might be better to replace the chassis-type
> > >> check with a acpi_dev_present("PNP0C60", NULL, -1) check.
> > >>
> > >> Mario, can you provide an acpidump and alsa-info.sh output for the
> > >> Dell XPS 9360, so that I can check if that might help with the issue
> > >> there, and thus is a potential candidate to replace the chassis-type
> > >> check?
> > >
> > > Unfortunately with WFH right now, I don't have access to a XPS 9630 to
> > > double check the patch series.
> > >
> > > However I do agree this should be a good approach.
> >
> > Ok, so lets stick with the chassis-type check (as amended by this patch)
> > for now then. Then once you are able to go to your office again, we
> > can examine the acpi_dev_present("PNP0C60", NULL, -1) alternative.
>
> I know XPS 13's are pretty popular, perhaps someone on the mailing list who has
> one can share ACPI dump in the interim.

https://github.com/intel/dptfxtract/issues/13
?

-- 
With Best Regards,
Andy Shevchenko