ubuntu-x-swat team mailing list archive

[Seth Forshee <seth.forshee@xxxxxxxxxxxxx>]

On Thu, Sep 22, 2011 at 08:30:45PM -0000, César Izurieta wrote:
> Seth, I've attached dmesg-stray-click.txt after following your
> instructions. Two middle clicks where fired during the test. I used two
> fingers and made an horizontal scroll for about one second.

What I see in the logs indicates that when you were scrolling your
fingers you get a couple of data points sometimes where the touchpad is
telling the driver that there was only a single contact on the touchpad.
So basically you end up with the following sequence for the number of
contact points being reported:

  1 -> 2 -> 1 -> 2 -> 1 -> 2 -> 0

I have a hard time understanding how any of that is getting interpreted
as a two-finger tap, but that's all I see that could conceivably be
causing the events. I've been trying to reproduce it on the hardware I
have, but I can't.

Well, I guess there is one other thing. If something in the packet is
getting misinterpreted as a button then I guess the driver could
literally be sending a button event. To check this, switch to a virtual
terminal and identify your touchpad in lsinput, then run

  sudo input-events <devnr> | grep BTN_MIDDLE

While this is running, do the motions on the touchpad that are giving
you middle clicks. If you see any output then the driver is interpreting
some of the data in the packets incorrectly.

If it doesn't generate output, and the driver is reporting the data from
the hardware correctly, then I don't know what can be done. I'll see if
I can find more out about how the synaptics client is identifying two
finger taps.

-- 
You received this bug notification because you are a member of Ubuntu-X,
which is subscribed to xserver-xorg-input-synaptics in Ubuntu.
https://bugs.launchpad.net/bugs/550625

Title:
  Alps touchpad is recognized but synaptics clients and scrolling do not
  work

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