mfd: sun4i-gpadc: Correct specified GPADC interrupt numbers

The identifiers are used as IRQ resource numbers, where 0 is treated
specially.

This fixes sun4i-gpadc-iio probe failed when request irq.

The backstack:
WARNING: CPU: 3 PID: 1 at drivers/base/platform.c:451
__platform_get_irq_byname+0xb8/0xc4
0 is an invalid IRQ number
Modules linked in:
CPU: 3 PID: 1 Comm: swapper/0 Not tainted 6.7.0-rc6 #9
Hardware name: Allwinner sun8i Family
unwind_backtrace
show_stack
dump_stack_lvl
__warn
warn_slowpath_fmt
__platform_get_irq_byname
platform_get_irq_byname
sun4i_irq_init
sun4i_gpadc_probe
platform_probe
really_probe
__driver_probe_device
driver_probe_device
__driver_attach
bus_for_each_dev
bus_add_driver
driver_register
do_one_initcall
do_initcall_level
do_initcalls
kernel_init_freeable
kernel_init

Log reports:
sun4i-gpadc-iio sun6i-a31-gpadc-iio.0: error -EINVAL: IRQ FIFO_DATA_PENDING
not found
sun4i-gpadc-iio: probe of sun6i-a31-gpadc-iio.0 failed with error -22

Signed-off-by: Fuyao Kashizuku <fuyao@sjterm.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://lore.kernel.org/r/ZYuFbUUus9apiCpq@debian.cyg
Signed-off-by: Lee Jones <lee@kernel.org>

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>

iio: adc: sun4i-gpadc-iio: add support for A33 thermal sensor

This adds support for the Allwinner A33 thermal sensor.

Unlike the A10, A13 and A31, the Allwinner A33 only has one channel
which is dedicated to the thermal sensor. Moreover, its thermal sensor
does not generate interruptions, thus we only need to directly read the
register storing the temperature value.

The MFD used by the A10, A13 and A31, was created to avoid breaking the
DT binding, but since the nodes for the ADC weren't there for the A33,
it is not needed.

Though the A33 does not have an internal ADC, it has a thermal sensor
which shares the same registers with GPADC of the already supported SoCs
and almost the same bits, for the same purpose (thermal sensor).

The thermal sensor behaves exactly the same (except the presence of
interrupts or not) on the different SoCs.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: adc: add support for Allwinner SoCs ADC

The Allwinner SoCs all have an ADC that can also act as a touchscreen
controller and a thermal sensor. This patch adds the ADC driver which is
based on the MFD for the same SoCs ADC.

This also registers the thermal adc channel in the iio map array so
iio_hwmon could use it without modifying the Device Tree. This registers
the driver in the thermal framework.

The thermal sensor requires the IP to be in touchscreen mode to return
correct values. Therefore, if the user is continuously reading the ADC
channel(s), the thermal framework in which the thermal sensor is
registered will switch the IP in touchscreen mode to get a temperature
value and requires a delay of 100ms (because of the mode switching),
then the ADC will switch back to ADC mode and requires also a delay of
100ms. If the ADC readings are critical to user and the SoC temperature
is not, this driver is capable of not registering the thermal sensor in
the thermal framework and thus, "quicken" the ADC readings.

This driver probes on three different platform_device_id to take into
account slight differences (registers bit and temperature computation)
between Allwinner SoCs ADCs.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Acked-for-MFD-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

mfd: Add support for Allwinner SoCs ADC

The Allwinner SoCs all have an ADC that can also act as a touchscreen
controller and a thermal sensor. For now, only the ADC and the thermal
sensor drivers are probed by the MFD, the touchscreen controller support
will be added later.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>