Previously, delta filtering was applied TSC co-ordinate readouts before
reporting a single value to user space. This patch replaces delta filtering
with median filtering. Median filtering sorts co-ordinate readouts, drops
min and max values, and reports the average of remaining values. This
method is more sensible than delta filtering. Median filtering is applied
only if number of readouts is greater than 3 else just average of
co-ordinate readouts is reported.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

This patch reads charge delay from tsc DT node and writes to
REG_CHARGEDELAY register. If the charge delay is not specified in DT then
default value of 0x400(CHARGEDLY_OPENDLY) is used.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

TSC interrupt handler had udelay to avoid reporting of false pen-up
interrupt to user space. This patch implements workaround suggesting in
Advisory 1.0.31 of silicon errata for am335x, thus eliminating udelay and
touchscreen lag. This also improves performance of touchscreen and
eliminates sudden jump of cursor at touch release.

IDLECONFIG and CHARGECONFIG registers are to be configured with same values
in order to eliminate false pen-up events. This workaround may result in
false pen-down to be detected, hence considerable charge step delay needs
to be added. The charge delay is set to 0xB000 (in terms of ADC clock
cycles) by default.

TSC steps are disabled at the end of every sampling cycle and EOS bit is
set. Once the EOS bit is set, the TSC steps need to be re-enabled to begin
next sampling cycle.

Signed-off-by: Brad Griffis <bgriffis@ti.com>
[vigneshr@ti.com: Ported the patch from v3.12 to v3.19rc1]
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

This patch makes the initial changes required to workaround TSC-false
pen-up interrupts. It is required to implement these changes in order to
remove udelay in the TSC interrupt handler and false pen-up events.  The
charge step is to be executed immediately after sampling X+. Hence TSC is
made to use higher numbered steps (steps 5 to 16 for 5 co-ordinate
readouts, 4 wire TSC configuration) and ADC to use lower ones. Further X
co-ordinate readouts must be the last to be sampled, thus co-ordinates are
sampled in the order Y-Z-X.

Signed-off-by: Brad Griffis <bgriffis@ti.com>
[vigneshr@ti.com: Ported the patch from v3.12 to v3.19rc1]
Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Some devices are not fast enough to differentiate between a fast-moving
contact and a new contact. This problem cannot be fully resolved because
information is truly missing, but it is possible to safe-guard against
obvious mistakes by restricting movement with a maximum displacement.

The new problem formulation for dmax > 0 cannot benefit from the speedup
for positive definite matrices, but since the convergence is faster, the
result is about the same. For a handful of contacts, the latency difference
is truly negligible.

Suggested-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Tested-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Henrik Rydberg <rydberg@bitmath.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

The Allwinner A31 SoC (sun6i) has the same resistive touchpanel controller
as on other sunxi platforms. The only difference between the variants is
the control bits for enabling operations are left-shifted by 1 on the A31.

Also update the comment for the original temperature sensor with
information from Allwinner.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

The touchscreen controller has a temperature sensor embedded in the SoC,
which already has hwmon support in the driver.

Add DT thermal zone support so we can use it with cpufreq for thermal
throttling.

This also adds a comment stating that we do not know the actual formula
for calculating the temperature.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Merge with mainline to bring in the latest thermal and other changes.

This reverts commit 9d469d033d135d80742a4e39e6bbb4519dd5eee1.

It breaks the Chromebook Pixel touchpad (and touchscreen).

Reported-by: Dirk Hohndel <dirk@hohndel.org>
Bisected-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nick Dyer <nick.dyer@itdev.co.uk>
Cc: Benson Leung <bleung@chromium.org>
Cc: Yufeng Shen <miletus@chromium.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: stable@vger.kernel.org  # v3.16+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull input layer fixes from Dmitry Torokhov:
 "Fixes for v7 protocol for ALPS devices and few other driver fixes.

  Also users can request input events to be stamped with boot time
  timestamps, in addition to real and monotonic timestamps"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: hil_kbd - fix incorrect use of init_completion
  Input: alps - v7: document the v7 touchpad packet protocol
  Input: alps - v7: fix finger counting for > 2 fingers on clickpads
  Input: alps - v7: sometimes a single touch is reported in mt[1]
  Input: alps - v7: ignore new packets
  Input: evdev - add CLOCK_BOOTTIME support
  Input: psmouse - expose drift duration for IBM trackpoints
  Input: stmpe - bias keypad columns properly
  Input: stmpe - enforce device tree only mode
  mfd: stmpe: add pull up/down register offsets for STMPE
  Input: optimize events_per_packet count calculation
  Input: edt-ft5x06 - fixed a macro coding style issue
  Input: gpio_keys - replace timer and workqueue with delayed workqueue
  Input: gpio_keys - allow separating gpio and irq in device tree