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From:   Jonathan Denose <jdenose@chromium.org>
Date:   Mon, 27 Nov 2023 10:38:57 -0600
Message-ID: <CALNJtpUHHaq6g0wSuyaNBxtOE9kt6vDzdAGGu6j=JJdJmerDWQ@mail.gmail.com>
Subject: Re: [PATCH] Input: i8042 - add quirk for Lenovo ThinkPad T14 Gen 1
To:     Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc:     linux-input@vger.kernel.org, Jonathan Denose <jdenose@google.com>,
        Hans de Goede <hdegoede@redhat.com>,
        Huacai Chen <chenhuacai@kernel.org>,
        Mattijs Korpershoek <mkorpershoek@baylibre.com>,
        Takashi Iwai <tiwai@suse.de>,
        Werner Sembach <wse@tuxedocomputers.com>,
        linux-kernel@vger.kernel.org
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Hi Dmitry

On Fri, Nov 24, 2023 at 10:45=E2=80=AFPM Dmitry Torokhov
<dmitry.torokhov@gmail.com> wrote:
>
> Hi Jonathan,
>
> On Mon, Sep 25, 2023 at 04:33:20PM -0500, Jonathan Denose wrote:
> > The ThinkPad T14 Gen 1 touchpad works fine except that clicking
> > and dragging by tapping the touchpad or depressing the touchpad
> > do not work. Disabling PNP for controller setting discovery enables
> > click and drag without negatively impacting other touchpad features.
>
> I would like to understand more on how enabling PnP discovery for i8042
> affects the touchpad. Do you see it using different interrupt or IO
> ports? What protocol does the touchpad use with/without PnP? If the
> protocol is the same, do you see difference in the ranges (pressure,
> etc) reported by the device?
>
> Thanks.
>
> --
> Dmitry

Without PnP discovery the touchpad is using the SynPS/2 protocol, with
PnP discovery, the touchpad is using the rmi4 protocol. Since the
protocols are different, so are the ranges but let me know if you
still want to see them.

Can you tell me how to check the interrupt/IO ports? I'm not sure how
to do that.

Thanks,
Jonathan