[Precise,SRU,PULL] Cypress PS/2 Trackpad driver

Bug reference:

        https://bugs.launchpad.net/ubuntu/+source/linux/+bug/978807
        'Cypress Trackpad' incorrectly detected as 'ImPS/2 Generic Wheel
        Mouse' in 'Dell XPS 13 Ultrabook'

Precise SRU justification:
http://kernel.ubuntu.com/git?p=kamal/ubuntu-precise.git;a=shortlog;h=refs/heads/cypress-for-precise

[IMPACT]

This patch set (cherry-picked from Quantal) provides a driver for the
Cypress PS/2 Trackpad found in the Dell XPS 13, XPS 15, and other laptop
models.

[TESTCASE]

The driver has been tested extensively in the "Sputnik Project" ISO and
kernel PPA.

To test:
1. Observe that this trackpad yields only basic pointer-motion events
without the new driver, but yields full multitouch support with the new
driver.
2. Verify that the new driver doesn't cause other non-Cypress trackpads
to fail.


[Regression Potential] 

I have verified that the driver doesn't adversely affect non-Cypress
trackpads by testing various laptops with Synaptics and Elantech
trackpads.  It is possible that other trackpads could be adversely
affected.


Thanks,

 -Kamal

----------

The following changes since commit 0aa8c3e8f03bf637334ce6af1771f56ca092ee1b:

  Linux 3.2.28 (2012-08-20 13:01:12 -0300)

are available in the git repository at:

  git://kernel.ubuntu.com/kamal/ubuntu-precise.git cypress-for-precise

for you to fetch changes up to 99b4513b2438d5a4b312b11232c4e85cf1931ffd:

  UBUNTU: SAUCE: [Config] add MOUSE_PS2_CYPRESS=y (2012-08-20 09:45:33 -0700)

----------------------------------------------------------------
Cypress Semiconductor Corporation (2):
      UBUNTU: SAUCE: input: Cypress PS/2 Trackpad mouse driver
      UBUNTU: SAUCE: input: Cypress PS/2 Trackpad link driver into psmouse-base

Kamal Mostafa (5):
      UBUNTU: SAUCE: input: Cypress PS/2 Trackpad code style cleanup
      UBUNTU: SAUCE: input: Cypress PS/2 Trackpad eliminate dead code
      UBUNTU: SAUCE: input: Cypress PS/2 Trackpad fix no-config stubs
      UBUNTU: SAUCE: input: Cypress PS/2 Trackpad set default debug_level=0
      UBUNTU: SAUCE: [Config] add MOUSE_PS2_CYPRESS=y

 debian.master/config/config.common.ubuntu |    1 +
 drivers/input/mouse/Kconfig               |   10 +
 drivers/input/mouse/Makefile              |    1 +
 drivers/input/mouse/cypress_ps2.c         |  943 +++++++++++++++++++++++++++++
 drivers/input/mouse/cypress_ps2.h         |  220 +++++++
 drivers/input/mouse/psmouse-base.c        |   40 ++
 drivers/input/mouse/psmouse.h             |    2 +
 7 files changed, 1217 insertions(+)
 create mode 100644 drivers/input/mouse/cypress_ps2.c
 create mode 100644 drivers/input/mouse/cypress_ps2.h

On Mon, Aug 20, 2012 at 10:51:18AM -0700, Kamal Mostafa wrote:
> [Regression Potential] 
> 
> I have verified that the driver doesn't adversely affect non-Cypress
> trackpads by testing various laptops with Synaptics and Elantech
> trackpads.  It is possible that other trackpads could be adversely
> affected.

I reviewed the patches when they went into quantal, and I think there's
little potential for regressions with other touchpads. There's a small
risk for conflicts with upstream stable updates, but those should be
easily resolved.

Seth