linux-toradex.git/drivers/input/touchscreen/ti_am335x_tsc.c, branch v4.14

Input: ti_am335x_tsc - fix incorrect step config for 5 wire touchscreen

2017-10-19T00:54:12+00:00

Step config setting for 5 wire touchscreen is incorrect for Y coordinates.
It was broken while we moved to DT. If you look close at the offending
commit bb76dc09ddfc ("input: ti_am33x_tsc: Order of TSC wires, made
configurable"), the change was:

- STEPCONFIG_XNP | STEPCONFIG_YPN;
+ ts_dev->bit_xn | ts_dev->bit_yp;

while bit_xn = STEPCONFIG_XNN and bit_yp = STEPCONFIG_YNN. Not quite the
same.

Fixes: bb76dc09ddfc ("input: ti_am33x_tsc: Order of TSC wires, made configurable")
Signed-off-by: Jeff Lance 
[vigneshr@ti.com: Rebase to v4.14-rc1]
Signed-off-by: Vignesh R 
Reviewed-by: Michael Nazzareno Trimarchi 
Signed-off-by: Dmitry Torokhov

Input: ti_am335x_tsc - use variable name for sizeof() operator

2016-06-01T21:21:11+00:00

Fix the code formatting to use the kernel preferred style
of using the actual variables to determize the size using
the sizeof() operator.

Signed-off-by: Andrew F. Davis 
Signed-off-by: Dmitry Torokhov

Input: ti_am335x_tsc - use SIMPLE_DEV_PM_OPS

2016-04-05T17:17:51+00:00

Instead of doing the dance with macro that either resolves to a pointer or
NULL, let's switch to using SIMPLE_DEV_PM_OPS().

Also let's mark suspend and resume methods as __maybe_unused instead of
guarding them with an #ifdef and rely on linker to drop unused code. Doing
so should allow better compile coverage.

Signed-off-by: Dmitry Torokhov

Input: ti_am335x_tsc - fix HWPEN interrupt handling

2016-01-08T01:26:22+00:00

Remove write to REG_IRQCLR and REG_IRQWAKEUP in interrupt handler for
IRQENB_HW_PEN as the resume handler should and does clear REG_IRQWAKEUP.
IRQENB_HW_PEN bit is set in irqclr so that all interrupts get cleared
later so let IRQENB_HW_PEN be cleared by that.

Without this patch wakeup events from TSC_ADC do not work because pending
interrupts in TSC_ADC were causing HW_PEN interrupt, needed for wake from
suspend modes, to get disabled immediately by IRQ handler after being
enabled and preventing wake from happening.

Signed-off-by: Dave Gerlach 
Signed-off-by: Dmitry Torokhov

Input: ti_am335x_tsc - replace delta filtering with median filtering

2015-02-03T19:50:39+00:00

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 
Signed-off-by: Dmitry Torokhov

Input: ti_am335x_tsc - read charge delay from DT

2015-02-03T19:50:38+00:00

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 
Signed-off-by: Dmitry Torokhov

Input: ti_am335x_tsc - remove udelay in interrupt handler

2015-02-03T19:50:38+00:00

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 
[vigneshr@ti.com: Ported the patch from v3.12 to v3.19rc1]
Signed-off-by: Vignesh R 
Signed-off-by: Dmitry Torokhov

Input: ti_am335x_tsc - interchange touchscreen and ADC steps

2015-02-03T19:50:37+00:00

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 
[vigneshr@ti.com: Ported the patch from v3.12 to v3.19rc1]
Signed-off-by: Vignesh R 
Acked-by: Jonathan Cameron 
Signed-off-by: Dmitry Torokhov

input: touchscreen: drop owner assignment from platform_drivers

2014-10-20T14:20:41+00:00

A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang

Input: ti_am335x_tsc - warn about incorrect spelling

2014-06-15T07:28:44+00:00

In the hopes that people run new kernels on their devices, let's add a
warning message asking users to have their DTS file fixed.

The goal is that by Linux 4.0 we will be able to remove support for the
bogus version of our touchscreen's DTS.

Signed-off-by: Felipe Balbi 
Acked-by: Mark Rutland 
Signed-off-by: Dmitry Torokhov