rtc: add real-time clock driver for NVIDIA Tegra

This is a platform driver that supports the built-in real-time clock on
Tegra SOCs.
Signed-off-by: Andrew Chew <achew@nvidia.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Acked-by: Wan ZongShun <mcuos.com@gmail.com>
Acked-by: Jon Mayo <jmayo@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/Kconfig

@@ -985,4 +985,14 @@ config RTC_DRV_LPC32XX
 	  This driver can also be buillt as a module. If so, the module
 	  will be called rtc-lpc32xx.
 
+config RTC_DRV_TEGRA
+	tristate "NVIDIA Tegra Internal RTC driver"
+	depends on RTC_CLASS && ARCH_TEGRA
+	help
+	  If you say yes here you get support for the
+	  Tegra 200 series internal RTC module.
+
+	  This drive can also be built as a module. If so, the module
+	  will be called rtc-tegra.
+
 endif # RTC_CLASS

drivers/rtc/Makefile

@@ -91,6 +91,7 @@ obj-$(CONFIG_RTC_DRV_STARFIRE)	+= rtc-starfire.o
 obj-$(CONFIG_RTC_DRV_STK17TA8)	+= rtc-stk17ta8.o
 obj-$(CONFIG_RTC_DRV_STMP)	+= rtc-stmp3xxx.o
 obj-$(CONFIG_RTC_DRV_SUN4V)	+= rtc-sun4v.o
+obj-$(CONFIG_RTC_DRV_TEGRA)	+= rtc-tegra.o
 obj-$(CONFIG_RTC_DRV_TEST)	+= rtc-test.o
 obj-$(CONFIG_RTC_DRV_TWL4030)	+= rtc-twl.o
 obj-$(CONFIG_RTC_DRV_TX4939)	+= rtc-tx4939.o