mfd: Add MAX77693 driver

This patch adds MFD driver for MAX77693 to enable its sub devices.

The MAX77693 is a multi-function devices. It includes PMIC,
MUIC(Micro USB Interface Controller), flash LED control and
haptic motor control.

Signed-off-by: Chanwoo Choi <cw00.choi@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>
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index af46ce0..a0e1b83 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -420,6 +420,18 @@
 	  individual components like LCD backlight, LEDs, GPIOs and Kepad
 	  under the corresponding menus.
 
+config MFD_MAX77693
+	bool "Maxim Semiconductor MAX77693 PMIC Support"
+	depends on I2C=y && GENERIC_HARDIRQS
+	select MFD_CORE
+	help
+	  Say yes here to support for Maxim Semiconductor MAX77693.
+	  This is a companion Power Management IC with Flash, Haptic, Charger,
+	  and MUIC(Micro USB Interface Controller) controls on chip.
+	  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_MAX8925
 	bool "Maxim Semiconductor MAX8925 PMIC Support"
 	depends on I2C=y && GENERIC_HARDIRQS