Disable the recalibration guard where new recalibrations are triggered
if we detect a packet too soon after calibrating - we found that this
results in erroneous recalibrations, and if the recalibration failed
then the rest of our badness-detection code will request another.

Add a module option disabling all of the recalibration code, in case
an OLPC deployment thinks all of the workarounds we have are doing
more damage than good and wants to experiment with them all disabled.

Based on work by Paul Fox.
Signed-off-by: NDaniel Drake <dsd@laptop.org>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Based on work by Paul Fox.
Signed-off-by: NDaniel Drake <dsd@laptop.org>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

In addition to forcing recalibrations upon detection of cursor jumps (and
performing them quicker than before), detect and discard errant 'jump'
packets caused by a firmware bug, which are then repeated with each one
being approximately half the delta of the one previously (as if it is
averaging out)

Based on original work by Paul Fox.
Signed-off-by: NDaniel Drake <dsd@laptop.org>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

The old implementation of spew detection simply tracked the overall
position delta of the cursor over every 100 packets. We found that
this causes occasional false positives in spew detection, and also
that the conditions of the spewy packets are perhaps more fixed than
we once thought.

Rework the spew detection to look for packets of specific small
delta, and only recalibrating if the overall movement delta stays
within expected bounds.

Also discard duplicate packets in the advanced mode, which appear
to be very common. If we don't, the spew detection kicks in far
too early. If we get a large spew of duplicates, request a
recalibration straight up.

Based on earlier work by Paul Fox.
Signed-off-by: NDaniel Drake <dsd@laptop.org>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Add a "hgpk_mode" sysfs attribute that allows selection between 3 options:
Mouse (the existing option), GlideSensor and PenTablet.

GlideSensor is an enhanced protocol for the regular touchpad mode that
additionally reports pressure and uses absolute coordinates. We suspect
that it may be more reliable than mouse mode in some environments.

PenTablet mode puts the touchpad into resistive mode, you must then use
a stylus as an input. We suspect this is the most reliable way to drive
the touchpad.

The GlideSensor and PenTablet devices expose themselves with the
intention of being combined with the synaptics X11 input driver.

Based on earlier work by Paul Fox.
Signed-off-by: NDaniel Drake <dsd@laptop.org>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

The variable 'dev' is unused in function 'hgpk_register'.
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Do not start protocol detection assuming that middle mouse is present,
instead let individual protocols explicitly set this capability.
This fixes issue with Synaptics touchpads pretending that they have
middle button when hardware clearly reports otherwise.
Reported-and-tested-by: NAndrey Borzenkov <arvidjaar@mail.ru>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

The OLPC XO laptop incorporates a combination touchpad/tablet device
which unfortunately requires frequent recalibration.  The driver will
force this automatically when various suspicious behaviors are
observed, and the user can recalibrate manually (with a special
keyboard sequence). There's currently no way, however, for an external
program to cause recalibration. We can not use the reconnect
capability which is already available in /sys because full reset of
the touchpad takes 1.1 - 1.2 secons which is too long.

This patch creates a new node in /sys which, when written with '1',
will force a touchpad recalibration; no other writes (or reads)
of this node are supported.
Signed-off-by: NPaul Fox <pgf@laptop.org>
Acked-by: NAndres Salomon <dilinger@collabora.co.uk>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

It is a fairly common operation to have a pointer to a work and to need a
pointer to the delayed work it is contained in.  In particular, all
delayed works which want to rearm themselves will have to do that.  So it
would seem fair to offer a helper function for this operation.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Acked-by: NIngo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Greg KH <greg@kroah.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When probing for the OLPC HGPK touchpad the ID of the probed touchpad is
emitted, but the debug is missing the terminating newline.  This causes
later information to run into it, and for that to be categorised
incorrectly at KERN_DBG.  Fix this up.
Reported-by: NMatt Zimmerman <mdz@canonical.com>
Signed-off-by: NAndy Whitcroft <apw@canonical.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

The HPGK touchpad that is found on the XO driver has historically
exhibitted eratic behaviour in various environments (very dry,
very humid, etc) that can be worked around via some delays. This
patch turns those delays into module parameters to make testing
simpler.
Signed-off-by: NPaul Fox <pgf@laptop.org>
Signed-off-by: NDeepak Saxena <dsaxena@laptop.org>
Acked-By: NAndres Salomon <dilinger@debian.org>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

The validate_byte check logic was backwards; it should return true for
an *invalid* packet.  Thanks to Jeremy Katz for spotting this one.
Signed-off-by: NAndres Salomon <dilinger@debian.org>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

This adds support for OLPC's touchpad.  It has lots of neat features,
none of which are enabled because the hardware is too buggy.  Instead,
we use it like a normal touchpad, but with a number of workarounds in
place to deal with the frequent hardware spasms.  Humidity changes,
sweat, tinfoil underwear, plugging in AC, drinks, evil felines.. All
tend to cause the touchpad to freak out.
Signed-off-by: NAndres Salomon <dilinger@debian.org>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>