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[Kent Baxley <1265885@xxxxxxxxxxxxxxxxxx>]

I think I know what might be happening here...

The firmware on these Synaptics touchpads supports i2c mode as well as
psmouse mode.  Older kernels prior to 3.11 didn't have very good i2c
support and the firmware on the touchpad would fall back to psmouse
mode.  psmouse mode worked nicely on machines pre-loaded with 12.04 and
probably worked OK up until 13.04.   Once the Saucy kernels were
introduced, the 3.11 kernels had better i2c support and thus the
touchpad would load up in i2c mode.

Synaptics was supposed to be working on some hid-multitouch i2c drivers
and I thought they would have been upstreamed by now.  Without them, the
touchpad will operate in *very* basic i2c mode.  This also explains the
difference between what you see in xinput with the older kernels (PS/2)
versus newer ones (DLL060A:00 06CB:2734).  So, yes, blacklisting i2c_hid
is one way to work around the problem.

I'll find out what the deal is with Synaptics...

-- 
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https://bugs.launchpad.net/bugs/1265885

Title:
  regression with respect touchpad

Status in “linux” package in Ubuntu:
  In Progress

Bug description:
  This regression occurs somewhere between 3.11.0-14-generic (latest on
  saucy) and 3.13.0-031300rc6-generic (a test kernel). On the earlier
  kernel, I actually  get settings for setting up my touchpad in the
  unity interface. With the updated kernel, those options disappear. I
  only get one set of options both my mouse and my touchpad instead of
  each one independently. It means that I can't set the pointer speed
  differently or turn on natural scrolling for my touchpad.

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