Input: adc-keys - drop bogus __refdata annotation

As the ADC ladder input driver does not have any code or data located in
initmem, there is no need to annotate the adc_keys_driver structure with
__refdata. Drop the annotation, to avoid suppressing future section
warnings.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/7091e8213602be64826fd689a7337246d218f3b1.1626255421.git.geert+renesas@glider.be
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: adc-keys - switch to using polled mode of input devices

We have added polled mode to the normal input devices with the intent of
retiring input_polled_dev. This converts adc-keys driver to use the
polling mode of standard input devices and removes dependency on
INPUT_POLLDEV.

Acked-by: Marco Felsch <m.felsch@pengutronix.de>
Link: https://lore.kernel.org/r/20191017204217.106453-6-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Input: keyboard - drop calls to platform_set_drvdata and i2c_set_clientdata

There is no call to i2c_get_clientdata(), platform_get_drvdata(),
or dev_get_drvdata() in any of the drivers in this patch.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: add ADC resistor ladder driver

A common way of multiplexing buttons on a single input in cheap devices is
to use a resistor ladder on an ADC. This driver supports that configuration
by polling an ADC channel provided by IIO.

Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>