mfd: max77840: Add support for MAX77840 PMIC core

Implement basic support for the MAX77840 PMIC core, including
initialization, power management, and core functions necessary for
submodules.

Signed-off-by: joan-na-good <joan.na@analog.com>

Author: joan-na-good

Kconfig.adi

@@ -96,6 +96,9 @@ config KERNEL_ALL_ADI_DRIVERS
 	imply REGULATOR_MAX77857
 	imply REGULATOR_MAX77541
 	imply MFD_MAX77541
+	imply REGULATOR_MAX77840
+	imply CHARGER_MAX77840
+	imply MFD_MAX77840
         imply REGULATOR_ADP5055
 
 source "drivers/clk/Kconfig.adi"

drivers/mfd/Kconfig

@@ -894,6 +894,19 @@ config MFD_MAX77714
 	  drivers must be enabled in order to use each functionality of the
 	  device.
 
+config MFD_MAX77840
+	tristate "Maxim Integrated MAX77840 Charger Support"
+	depends on I2C=y
+	select MFD_CORE
+	select REGMAP_I2C
+	select REGMAP_IRQ
+	help
+	  Say yes here to add support for Maxim Integrated MAX77840.
+	  This is a 3A Switch Mode Charger with Fuel Gauge.
+	  This driver provides common support for accessing the device,
+	  additional drivers must be enabled in order to use the functionality
+	  of the device.
+
 config MFD_MAX77843
 	bool "Maxim Semiconductor MAX77843 PMIC Support"
 	depends on I2C=y

drivers/mfd/Makefile

@@ -163,6 +163,7 @@ obj-$(CONFIG_MFD_MAX77650)	+= max77650.o
 obj-$(CONFIG_MFD_MAX77686)	+= max77686.o
 obj-$(CONFIG_MFD_MAX77693)	+= max77693.o
 obj-$(CONFIG_MFD_MAX77714)	+= max77714.o
+obj-$(CONFIG_MFD_MAX77840)	+= max77840.o
 obj-$(CONFIG_MFD_MAX77843)	+= max77843.o
 obj-$(CONFIG_MFD_MAX8907)	+= max8907.o
 max8925-objs			:= max8925-core.o max8925-i2c.o