mfd: max77686: Convert to use maple tree register cache

The maple tree register cache is based on a much more modern data structure
than the rbtree cache and makes optimisation choices which are probably
more appropriate for modern systems than those made by the rbtree cache.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Link: https://lore.kernel.org/r/20231001-mfd-maxim-maple-v1-2-cdfeb48a4d15@kernel.org
Signed-off-by: Lee Jones <lee@kernel.org>

mfd: Explicitly include correct DT includes

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230714174731.4059811-1-robh@kernel.org
Signed-off-by: Lee Jones <lee@kernel.org>

mfd: Switch i2c drivers back to use .probe()

After commit b8a1a4cd5a98 ("i2c: Provide a temporary .probe_new()
call-back type"), all drivers being converted to .probe_new() and then
03c835f498b5 ("i2c: Switch .probe() to not take an id parameter") convert
back to (the new) .probe() to be able to eventually drop .probe_new() from
struct i2c_driver.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230515182752.10050-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Lee Jones <lee@kernel.org>

mfd: max77686: Remove #ifdef guards for PM related functions

Use the new DEFINE_SIMPLE_DEV_PM_OPS() and pm_sleep_ptr() macros
to handle the .suspend/.resume callbacks.

These macros allow the suspend and resume functions to be automatically
dropped by the compiler when CONFIG_SUSPEND is disabled, without having
to use #ifdef guards.

This has the advantage of always compiling these functions in,
independently of any Kconfig option. Thanks to that, bugs and other
regressions are subsequently easier to catch.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Lee Jones <lee@kernel.org>

rtc: max77686: Rename day-of-month defines

RTC_DATE and REG_RTC_DATE are used for the registers holding the day of
month. Rename these constants to mean what they mean.

Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Do not enforce (incorrect) interrupt trigger type

Interrupt line can be configured on different hardware in different way,
even inverted. Therefore driver should not enforce specific trigger
type - edge falling - but instead rely on Devicetree to configure it.

The Maxim 77686 datasheet describes the interrupt line as active low
with a requirement of acknowledge from the CPU therefore the edge
falling is not correct.

The interrupt line is shared between PMIC and RTC driver, so using level
sensitive interrupt is here especially important to avoid races. With
an edge configuration in case if first PMIC signals interrupt followed
shortly after by the RTC, the interrupt might not be yet cleared/acked
thus the second one would not be noticed.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210602110445.33536-2-krzysztof.kozlowski@canonical.com

mfd: max77686: Drop of_match_ptr from of_device_id table

The driver can match only via the DT table so the table should be always
used and the of_match_ptr does not have any sense (this also allows ACPI
matching via PRP0001, even though it is not relevant here). This fixes
compile warning (!CONFIG_OF on x86_64):

drivers/mfd/max77686.c:148:34: warning: ‘max77686_pmic_dt_match’ defined but not used [-Wunused-const-variable=]

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: maxim: Add SPDX license identifiers

Replace GPL v2.0+ license statements with SPDX license identifiers.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Remove I2C device ID table

The driver is only used in DT platforms so there's no need to
have an i2c_device_id table.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Tested-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Use the struct i2c_driver .probe_new instead of .probe

If a driver is only used in DT platforms, there's no need to get the
i2c_device_id as an argument of the probe function. Since this data
can be get from the matching of_device_id.

There's a temporary .probe_new field in struct i2c_driver that can be
used as probe callback for the case when i2c_device_id won't be used.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Tested-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Use of_device_get_match_data() helper

Use the generic helper to get the matched of_device_id .data, instead of
open coding it.

The driver was checking if matching the OF node with the driver's OF table
was failing, but this doesn't make too much sense since this can't happen
in practice. The fact the probe function was called, means OF registered a
device with a valid compatible string so a of_device_get_match_data() call
will always succeed. So just remove this unneeded check.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Tested-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Don't attempt to get i2c_device_id .data

The driver is only used in platforms that have DT support so always the
I2C device .data will be get from the matched OF node and never will be
from the I2C device ID table.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Tested-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Use devm_mfd_add_devices and devm_regmap_add_irq_chip

Use devm_mfd_add_devices() for adding MFD child devices and
devm_regmap_add_irq_chip() for IRQ chip registration.

This reduces the error code path and .remove callback for removing
MFD child devices and deleting IRQ chip data.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Use module_i2c_driver() instead of subsys initcall

The driver's init and exit function don't do anything besides adding and
deleting the I2C driver so the module_i2c_driver() macro could be used.

Currently is not being used because the driver is initialized at subsys
initcall level, claiming that this is done to allow consumers devices to
use the resources provided by this driver. But dependencies are in DT so
manual ordering of init calls is not necessary any more.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Andi Shyti <andi.shyti@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686/max77693: Fix misspelled Samsung address

Correct smasung.com into samsung.com.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Add max77802 to I2C device ID table

The max77686 MFD driver supports both the Maxim 77686 and Maxim 77802
PMICs but only the OF device table contains entries for both devices.

The max77802 entry is missing in the I2C device ID table which isn't
a problem currently since the driver only supports DT but it will be
needed if the driver is changed to be built as a module since the I2C
core always reports a I2C modalias uevent so auto-load will not work.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Export OF module alias information

When the device is registered via OF, the OF table is used to match the
driver instead of the I2C device ID table but the entries in the latter
are used as aliasses to load the module if the driver was not built-in.

This is because the I2C core always reports an I2C module alias instead
of an OF one but that could change so it is better to always export it.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

rtc: max77686: move initialisation of rtc regmap, irq chip locally

To make RTC block of MAX77686/MAX77802 as independent driver,
move the registration of i2c device, regmap for register access
and irq_chip for interrupt support inside the RTC driver.
Removed the same initialisation from MFD driver.

Having this change will allow to reuse this driver for different
PMIC/devices from Maxim Semiconductor if they kept same RTC IP on
different PMIC. Some of examples as PMIC MAX77620, MAX20024 where
same RTC IP used and hence driver for these chips will use this
driver only for RTC support.

Suggested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

mfd: max77686: do not set i2c client data for rtc i2c client

There is different RTC I2C address for RTC block in MAX77686.
Driver is creating dummy i2c client for this address to access
the register of this IP block.

As there is no call to i2c_get_clientdata() for rtc_i2c client,
there is no need to store pointer and hence removing the call
to set client data for rtc i2c client.

Suggested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

mfd: Use to_i2c_client() instead of open-coding it

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: Drop owner assignment from i2c_drivers

i2c_driver does not need to set an owner because i2c_register_driver()
will set it.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686/802: Remove support for board files

The driver is used only on Exynos based boards with DTS support.
After removal of board file support from max77686 and max77802 regulator
drivers, the MFD driver can be converted to DTS-only version. This
simplifies a little the code:
1. No dead (unused) entries in platform_data structure.
2. More code removed.
3. Regulator driver does not depend on allocated memory
from MFD driver.
4. It makes also easier extending the regulator driver.

Add to the max77686 MFD driver dependency on CONFIG_OF because without
DTS the regulator drivers (max77686 and max77802) won't bind.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Constify struct regmap_config

The regmap_config struct may be const because it is not modified by the
driver and regmap_init() accepts pointer to const.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Remove check which is always true

As 'reg' is unsigned, it can't be less than 0, so checking if it is
greater than or equal to 0 will always result in a true condition.

Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Ensure device type IDs are architecture agnostic

Extinguishes:

../drivers/mfd/max77686.c: In function ‘max77686_i2c_probe’:
../drivers/mfd/max77686.c:254:20:
warning: cast from pointer to integer of different size

Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Add Maxim 77802 PMIC support

Maxim MAX77802 is a power management chip that contains 10 high
efficiency Buck regulators, 32 Low-dropout (LDO) regulators used
to power up application processors and peripherals, a 2-channel
32kHz clock outputs, a Real-Time-Clock (RTC) and a I2C interface
to program the individual regulators, clocks outputs and the RTC.

This patch adds support for MAX77802 to the MAX77686 driver and is
based on a driver added to the Chrome OS kernel 3.8 by Simon Glass.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Fix 'line over 80 chars' warning

This is part of an effort to clean-up the MFD subsystem.

+WARNING: line over 80 characters
+ &max77686_rtc_regmap_config);

total: 0 errors, 1 warnings, 299 lines checked

Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Remove unneeded OOM error message

There is no need to print out-of-memory errors since this is already
done by the memory management subsystem which even calls dump_stack().

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Make error checking consistent

Error checking across the driver is mostly consistent besides
a few exceptions, so change these exceptions for consistency.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Return correct error when pdata isn't found

When platform data is not found an -EIO (I/O error) code is returned.
This doesn't seem to be the correct error so better return -EINVAL
(Invalid argument) which is what most drivers do in this case.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Make platform data over-rule DT

The function max77802_i2c_parse_dt_pdata() should only be called
if there isn't already platform data for the device.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Don't define dummy function if OF isn't enabled

When the CONFIG_OF option was not enabled, a dummy function
max77686_i2c_parse_dt_pdata() was defined since this is called
unconditionally on probe(). Just always define the real function
and conditionally call it if CONFIG_OF is enabled instead.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Add power management support

The driver doesn't have PM operations defined so add a suspend
and resume function handlers to allow the PMIC IRQ to wakeup
the system when it is put into a sleep state.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Convert to use regmap_irq

By using the generic IRQ support in the Register map API, it
is possible to get rid max77686-irq.c and simplify the code.

Suggested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Tested-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Make of_device_id array const

Array of struct of_device_id may be be const as expected by
of_match_table field.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Fix possible NULL pointer dereference on i2c_new_dummy error

During probe the driver allocates dummy I2C device for RTC with
i2c_new_dummy() but it does not check the return value of this call.

In case of error (i2c_new_device(): memory allocation failure or I2C
address cannot be used) this function returns NULL which is later used
by i2c_unregister_device().

If i2c_new_dummy() fails for RTC device, fail also the probe for main
MFD driver.

Cc: stable@vger.kernel.org
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Fix regmap resource leak on driver remove

The regmap used by max77686 MFD driver was not freed with regmap_exit()
on driver exit. This lead to leak of resources.

Replace regmap_init_i2c() call in driver probe with initialization of
managed register map so the regmap will be properly freed by the device
management code.

Cc: stable@vger.kernel.org
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: maxim: Constify struct mfd_cell where possible

As of commit 03e361b25ee8dfb1fd9b890072c23c4aae01c6c7 ("mfd: Stop setting
refcounting pointers in original mfd_cell arrays"), the "cell" parameter of
mfd_add_devices() is "const" again. Hence make all cell data passed to
mfd_add_devices() const where possible.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Include linux/of.h header

'of_match_ptr' is defined in linux/of.h. Include it explicitly to
avoid breakage in the future.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: Use dev_get_platdata()

Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: max77686: Convert to managed resources for allocating memory

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

mfd: max77687: Add registration of max77686-clk

The MAX77686 clock driver has been in-tree for over 6 months, but never
actually enabled through the MFD registration before.

Add it to the table so the device will probe and configure properly.

Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

mfd: max77686: Use NULL instead of 0

'data' is a pointer and hence use NULL instead of 0.
Silences the following warning:
drivers/mfd/max77686.c:49:50: warning: Using plain integer as NULL pointer

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Jonghwa Lee <jonghwa3.lee@samsung.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

mfd: max77686: Init max77686->dev before using it

Current code uses max77686->dev in the dev_err call before setting it to
&i2c->dev. Fix it.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

mfd: remove use of __devinitdata

CONFIG_HOTPLUG is going away as an option so __devinitdata is no
longer needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Cc: Peter Tyser <ptyser@xes-inc.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mfd: core: Push irqdomain mapping out into devices

Currently the MFD core supports remapping MFD cell interrupts using an
irqdomain but only if the MFD is being instantiated using device tree
and only if the device tree bindings use the pattern of registering IPs
in the device tree with compatible properties. This will be actively
harmful for drivers which support non-DT platforms and use this pattern
for their DT bindings as it will mean that the core will silently change
remapping behaviour and it is also limiting for drivers which don't do
DT with this particular pattern. There is also a potential fragility if
there are interrupts not associated with MFD cells and all the cells are
omitted from the device tree for some reason.

Instead change the code to take an IRQ domain as an optional argument,
allowing drivers to take the decision about the parent domain for their
interrupts. The one current user of this feature is ab8500-core, it has
the domain lookup pushed out into the driver.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

mfd: core: Push irqdomain mapping out into devices

Currently the MFD core supports remapping MFD cell interrupts using an
irqdomain but only if the MFD is being instantiated using device tree
and only if the device tree bindings use the pattern of registering IPs
in the device tree with compatible properties. This will be actively
harmful for drivers which support non-DT platforms and use this pattern
for their DT bindings as it will mean that the core will silently change
remapping behaviour and it is also limiting for drivers which don't do
DT with this particular pattern. There is also a potential fragility if
there are interrupts not associated with MFD cells and all the cells are
omitted from the device tree for some reason.

Instead change the code to take an IRQ domain as an optional argument,
allowing drivers to take the decision about the parent domain for their
interrupts. The one current user of this feature is ab8500-core, it has
the domain lookup pushed out into the driver.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

mfd: Guard max77686_pmic_dt_match with CONFIG_OF

This fixes below build warning if CONFIG_OF is not set.

CC drivers/mfd/max77686.o
drivers/mfd/max77686.c:37:42: warning: 'max77686_pmic_dt_match' defined but not used [-Wunused-variable]

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

mfd: Add device tree support for max77686

This patch adds device tree support for mfd driver and adds
Documentation/devicetree/bindings/mfd/max77686.txt.
This patch also intialize max77686 pointer to NULL in max77686_i2c_probe
to silent a compile time warning.

Signed-off-by: Yadwinder Singh Brar <yadi.brar@samsung.com>
Reviwed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

mfd: Allow to specify max77686 interrupt through DT or platform file also

Presently driver expects irq_gpio pin in platform data and maps it to irq
itself. But we can also directly specify the interrupt in DT or platform file.

Signed-off-by: Yadwinder Singh Brar <yadi.brar@samsung.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

mfd: Remove unused max77686 iolock mutex

Now this driver is using regmap API, the iolock mutex is not used and
can be removed.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

mfd: Add Maxim 77686 driver

This patch is device driver for MAX77686 chip.
MAX77686 is PMIC and includes regulator and rtc on it.
This driver is core of MAX77686 chip, so provides common support for
accessing on-chip devices. It uses irq_domain to manage irq and regmap
to read/write data to its register with i2c bus.

Signed-off-by: Chiwoong Byun <woong.byun@samsung.com>
Signed-off-by: Jonghwa Lee <jonghwa3.lee@samsung.com>
Signed-off-by: Myungjoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>