Re: [PATCH 0/3] Input: synaptics - multitouch and multifinger support

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

On Friday, October 08, 2010 10:15:35 am Chase Douglas wrote:
> On Fri, 2010-10-08 at 18:37 +0200, Takashi Iwai wrote:
> > At Fri,  8 Oct 2010 10:57:57 -0400,
> > 
> > Chase Douglas wrote:
> > > 
> > >
> > > Tobyn Bertram reverse engineered the multitouch protocol for Synaptics
> > > devices. I've been able to take his work and produce a series of
> > > commits to enable MT and multifinger (MF) support.
> > >
> > > 
> > >
> > > Unfortunately, there's a tricky issue with some Synaptics touchpads
> > > that have integrated buttons. For example, the left and right buttons
> > > on the touchpad of my Dell Mini 1012 consist of the lower ~20% of the
> > > touchpad surface. The touchpad physically clicks under these areas.
> > >
> > > 
> > >
> > > The X synaptics input module now has a parameter to disable touches
> > > occuring over the button area, but this solution still doesn't work
> > > perfectly. If you click a button and drag with another finger near the
> > > clicking finger, the touchpad gets confused.
> > >
> > > 
> > >
> > > Now that we have full MT support, we can try to handle this scenario
> > > better. What I've found to work best is to make touches vanish if they
> > > occur over the button area of the trackpad while any button is held.
> > > This works in conjunction with the X synaptics driver to disable
> > > single touch control over the button area. With full MT support, the
> > > touchpad doesn't seem to get confused when a click and drag occurs
> > > with two fingers close to each other, and it enables MT gestures and
> > > MF support across the entire trackpad when no buttons are held.
> > >
> > > 
> > >
> > > The first question is whether this seems appropriate to others, or if
> > > some other method would work better. Secondarily, should the solution
> > > occur in the kernel, like I have in the third patch of this series, or
> > > should it occur in the X input module? Although we don't have this
> > > information today, we may be able to query the touchpad in the future
> > > to know the area of the integrated buttons. If that were possible,
> > > would the recommended location for the hack change?
> >
> > 
> >
> > Great!  Finally someone found it out!
> > I found this and made a series of patches in 4 months ago.  Since
> > then, Novell legal prohibited me to send the patches to the upstream
> > due to "possible patent infringing".  Now you cracked out.  Yay.
> >
> > 
> >
> > FWIW, my corresponding patch is below.  It really looks similar in the
> > end ;)  I added a kconfig just to be safer.
> >
> > 
> >
> > Regarding the "clickpad" support: in my case, I implemented almost
> > everything about it in xorg driver.  I'm going to submit xorg
> > patches.
> 
> So I'm confused. I was working off of source code posted to:
> 
> https://bugs.launchpad.net/utouch/+bug/633225
> 
> I was under the impression that someone else had reverse engineered the
> protocol and written patches. But the code is exactly the same as what
> you've posted here. If you're the originator of the work, and my patch
> is accepted, I think we'll need your SOB on it.

Comment #6 is quite clear on this matter:

> Takashi Iwai from OpenSuse has done quite a bit of work for the Synaptics
> Clickpad including some experimental multitouch support, his repo is here:
> http://download.opensuse.org/repositories/home:/tiwai:/clickpad:/openSUSE_
> 11.3/openSUSE_11.3/src/
> 
> I have played around with the synaptics.c code in the kernel to add
> multitouch events (ABS_MT_POSITION_X, ABS_MT_POSITION_Y, ABS_MT_PRESSURE)
> using Takashi's work as a model.

So I do believe we need to have Takashi's SOB at the very least and maybe
credit him as the author of the patches.

-- 
Dmitry