rtc: max77686: add Maxim 77686 driver

Add a driver to support max77686 rtc.  MAX77686 rtc support smpl and wtsr
mode.  It has two alarm register which can be used for alarming to wake
system up.  This drvier uses regmap to access its register.

[akpm@linux-foundation.org: remove inline, __devinit annotations]
[jg1.han@samsung.com: fix build warnings]
[akpm@linux-foundation.org: simplify code]
Signed-off-by: Chiwoong Byun <woong.byun@samsung.com>
Signed-off-by: Jonghwa Lee <jonghwa3.lee@samsung.com>
Signed-off-by: Myugnjoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/Kconfig

@@ -243,6 +243,16 @@ config RTC_DRV_MAX8998
 	  This driver can also be built as a module. If so, the module
 	  will be called rtc-max8998.
 
+config RTC_DRV_MAX77686
+	tristate "Maxim MAX77686"
+	depends on MFD_MAX77686
+	help
+	  If you say yes here you will get support for the
+	  RTC of Maxim MAX77686 PMIC.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called rtc-max77686.
+
 config RTC_DRV_RS5C372
 	tristate "Ricoh R2025S/D, RS5C372A/B, RV5C386, RV5C387A"
 	help

drivers/rtc/Makefile

@@ -71,6 +71,7 @@ obj-$(CONFIG_RTC_DRV_MAX8907)	+= rtc-max8907.o
 obj-$(CONFIG_RTC_DRV_MAX8925)	+= rtc-max8925.o
 obj-$(CONFIG_RTC_DRV_MAX8998)	+= rtc-max8998.o
 obj-$(CONFIG_RTC_DRV_MAX6902)	+= rtc-max6902.o
+obj-$(CONFIG_RTC_DRV_MAX77686)	+= rtc-max77686.o
 obj-$(CONFIG_RTC_DRV_MC13XXX)	+= rtc-mc13xxx.o
 obj-$(CONFIG_RTC_DRV_MSM6242)	+= rtc-msm6242.o
 obj-$(CONFIG_RTC_DRV_MPC5121)	+= rtc-mpc5121.o