Input: rotary-encoder - remove references to platform data from docs

To use this driver in your system, register a platform_device with the

name 'rotary-encoder' and associate the IRQs and some specific platform

data with it.

struct rotary_encoder_platform_data is declared in

include/linux/rotary-encoder.h and needs to be filled with the number of

steps the encoder has and can carry information about externally inverted

signals (because of an inverting buffer or other reasons). The encoder

can be set up to deliver input information as either an absolute or relative

axes. For relative axes the input event returns +/-1 for each step. For

absolute axes the position of the encoder can either roll over between zero

and the number of steps or will clamp at the maximum and zero depending on

the configuration.

Because GPIO to IRQ mapping is platform specific, this information must

be given in separately to the driver. See the example below.

data with it. Because the driver uses generic device properties, this can

be done either via device tree, ACPI, or using static board files, like in

example below:

::

	/* board support file example */

	#include <linux/input.h>

    #include <linux/rotary_encoder.h>

	#include <linux/gpio/machine.h>

	#include <linux/property.h>

	#define GPIO_ROTARY_A 1

	#define GPIO_ROTARY_B 2

    static struct rotary_encoder_platform_data my_rotary_encoder_info = {

	    .steps		= 24,

	    .axis		= ABS_X,

	    .relative_axis	= false,

	    .rollover	= false,

	    .gpio_a		= GPIO_ROTARY_A,

	    .gpio_b		= GPIO_ROTARY_B,

	    .inverted_a	= 0,

	    .inverted_b	= 0,

	    .half_period	= false,

	    .wakeup_source	= false,

	static struct gpiod_lookup_table rotary_encoder_gpios = {

		.dev_id = "rotary-encoder.0",

		.table = {

			GPIO_LOOKUP_IDX("gpio-0",

					GPIO_ROTARY_A, NULL, 0, GPIO_ACTIVE_LOW),

			GPIO_LOOKUP_IDX("gpio-0",

					GPIO_ROTARY_B, NULL, 1, GPIO_ACTIVE_HIGH),

			{ },

		},

	};

	static const struct property_entry rotary_encoder_properties[] __initconst = {

		PROPERTY_ENTRY_INTEGER("rotary-encoder,steps-per-period", u32, 24),

		PROPERTY_ENTRY_INTEGER("linux,axis",			  u32, ABS_X),

		PROPERTY_ENTRY_INTEGER("rotary-encoder,relative_axis",	  u32, 0),

		{ },

	};

	static struct platform_device rotary_encoder_device = {

		.name		= "rotary-encoder",

		.id		= 0,

	    .dev		= {

		    .platform_data = &my_rotary_encoder_info,

	    }

	};

	...

	gpiod_add_lookup_table(&rotary_encoder_gpios);

	device_add_properties(&rotary_encoder_device, rotary_encoder_properties);

	platform_device_register(&rotary_encoder_device);

	...

Please consult device tree binding documentation to see all properties

supported by the driver.