On Thu, 2018-05-31 at 13:44 -0700, Laura Abbott wrote:
On 05/24/2018 04:13 PM, Timur Kristóf wrote:
> Hi,
>
> On the XPS 13 9360 and 9370 xinput sees two touchpads instead of
> one:
> ⎡ Virtual core pointer id=2 [master
> pointer (3)]
> ⎜ ↳ Virtual core XTEST
> pointer id=4 [slave pointer (2)]
> ⎜ ↳ DELL07E6:00 06CB:76AF
> Touchpad id=12 [slave pointer (2)]
> ⎜ ↳ SynPS/2 Synaptics
> TouchPad id=17 [slave pointer (2)]
>
> dmesg also gives me the following:
>
> [ 1.429811] psmouse serio1: synaptics: Your touchpad (PNP:
> DLL07e6
> PNP0f13) says it can support a different bus. If i2c-hid and hid-
> rmi
> are not used, you might want to try setting
> psmouse.synaptics_intertouch to 1 and report this to
> linux-input(a)vger.kernel.org.
>
> The Dell one is the real touchpad, the other one is an artifact of
> the
> psmouse driver. Weird touchpad freezes and jittering issues can be
> observed when both of these devices are there. The general advice
> on
> the web is to blacklist the psmouse driver. (This is also published
> by
> Dell as a .deb package which contains a config file doing just
> this.)
>
> However, on Fedora I cannot blacklist the psmouse driver because it
> is
> compiled built-in instead of as a module. Could you guys change the
> Fedora kernel config to compile it as a module instead?
>
> Thanks & best regards,
> Timur
So assuming nobody else has objections, I think it's okay to at
least try this on rawhide and see if it uncovers any other problems.
Thanks,
Laura
Looking into this a bit more, the root cause of this issue is that the
touchpad is wired up in such a way that it is accessible on both PS/2
and I2C. I2C is preferred and used by i2c-hid but at the same time the
PS/2 interface is also picked up by psmouse. Thus, Xorg sees the two
interfaces as two different devices.
Solution would be to somehow remove the psmouse-detected device node
from the system when i2c-hid detects the same device. Is this possible?
Best regards,
Timur