Re: [PATCH v2 0/7] New Lenovos 2015 touchpads: party time!

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Thu, Mar 19, 2015 at 01:06:49PM -0400, Benjamin Tissoires wrote:
> On Mar 19 2015 or thereabouts, Yves-Alexis Perez wrote:
> > On Thu, Mar 19, 2015 at 11:58:31AM -0400, Benjamin Tissoires wrote:
> > > On Mar 19 2015 or thereabouts, Yves-Alexis Perez wrote:
> > > Again, sorry, I thought I answered it. With the kernel patches applied:
> > > - disabled in the bios without psmouse.proto=imps -> touchpad still
> > >   enabled, trackstick + buttons working
> > > - disabling in the bios + psmouse.proto=imps -> touchpad disabled,
> > >   trackstick + buttons working
> > > - enabled in the bios + psmouse.proto=imps -> touchpad barely usable,
> > >   trackstick + buttons working
> > > 
> > > That should cover all the cases :)
> > > 
> > Actually, one is missing: “touchpad enabled / without
> > psmouse.proto=imps”, but it doesn't really matter for me since I'm not
> > using the touchpad anyway.
> 
> Yes, but that is the most used case, and if this one was not working
> then the patch series would have been moot :)
> 
> > 
> > But that also means if I want a disabled touchpad (without using xinput
> > disable) I'm forced to use psmouse.proto=imps. It does work fine but I
> > then lose the speed and sensitivity attributes (in
> > /sys/devices/platform/i8042/...) and the Trackpoint device itself is
> > gone from the input subsystem (everything goes to the touchpad one).
> > 
> > I find that a bit confusing, and think it'd be best if the touchpad
> > disabling could be handled even when IMPS/2 is not used, but maybe it's
> > impossible to do?

It is possible, but that task is on Lenovo's BIOS engineers to
implement. The kernel queries the device and responds accordingly; there
is no separate "check BIOS settings" pass. "proto=imps" simply tells
psmouse driver to skip the advanced protocol "magic knocks" and try
initalize mouse as MS Intellimouse compatible device.

I'd be curious to compare i8042 data (i8042.debug) from booting with
both proto=imps and without (note that keystrokes for your password will
be recorded there if you decide to post the logs), but again just for
curiosity's sake as I wonder how exactly they done disabling that it
only works for Intellimouse mode.

Thanks.

-- 
Dmitry