Instead of using old GPIO API, let's switch to GPIOD API, which
automatically handles polarity.
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Some encoders have both outputs low in stable states, others also have
a stable state with both outputs high (half-period mode) and some have
a stable state in all steps (quarter-period mode). The driver used to
support the former states and with this change it can also support the
later.

This commit also deprecates the 'half-period' property and introduces
a new property 'steps-per-period'. This property specifies the
number of steps (stable states) produced by the rotary encoder
for each GPIO period.
Signed-off-by: NGuido Martínez <guido@vanguardiasur.com.ar>
Signed-off-by: NEzequiel Garcia <ezequiel@vanguardiasur.com.ar>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

This patch adds wake up support to GPIO rotary encoders.
Signed-off-by: NSylvain Rochet <sylvain.rochet@finsecur.com>
Reviewed-by: NJohan Hovold <johan@kernel.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Add support for encoders that have two detents per input signal period.
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Acked-by: NDaniel Mack <zonque@gmail.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

The rotary encoder driver only supports returning input events
for ABS_* axes, this adds support for REL_* axes.  The relative
axis input event is reported as -1 for each counter-clockwise
step and +1 for each clockwise step.

The ability to clamp the position of ABS_* axes between 0 and
a maximum of "steps" has also been added.
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NDaniel Mack <daniel@caiaq.de>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

This patch adds a generic driver for rotary encoders connected to GPIO
pins of a system. It relies on gpiolib and generic hardware irqs. The
documentation that also comes with this patch explains the concept and
how to use the driver.
Signed-off-by: NDaniel Mack <daniel@caiaq.de>
Tested-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>