rtc: rc5t619: Add Ricoh RC5T619 RTC driver

Add an RTC driver for the RTC device on Ricoh MFD RC5T619,
which is implemented as a variant of RN5T618.

rtc-range output:
Testing 2000-02-28 23:59:59.
OK

Testing 2038-01-19 03:14:07.
OK

Testing 2069-12-31 23:59:59.
OK

Testing 2099-12-31 23:59:59.
KO RTC_RD_TIME returned 22 (line 138)

Testing 2100-02-28 23:59:59.
KO RTC_SET_TIME returned 34 (line 122)

Testing 2106-02-07 06:28:15.
KO RTC_SET_TIME returned 34 (line 122)

Testing 2262-04-11 23:47:16.
KO RTC_SET_TIME returned 34 (line 122)
Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/rtc/Kconfig

@@ -591,6 +591,16 @@ config RTC_DRV_RC5T583
 	  This driver can also be built as a module. If so, the module
 	  will be called rtc-rc5t583.
 
+config RTC_DRV_RC5T619
+	tristate "RICOH RC5T619 RTC driver"
+	depends on MFD_RN5T618
+	help
+	  If you say yes here you get support for the RTC on the
+	  RICOH RC5T619 chips.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called rtc-rc5t619.
+
 config RTC_DRV_S35390A
 	tristate "Seiko Instruments S-35390A"
 	select BITREVERSE

drivers/rtc/Makefile

@@ -137,6 +137,7 @@ obj-$(CONFIG_RTC_DRV_PXA)	+= rtc-pxa.o
 obj-$(CONFIG_RTC_DRV_R7301)	+= rtc-r7301.o
 obj-$(CONFIG_RTC_DRV_R9701)	+= rtc-r9701.o
 obj-$(CONFIG_RTC_DRV_RC5T583)	+= rtc-rc5t583.o
+obj-$(CONFIG_RTC_DRV_RC5T619)	+= rtc-rc5t619.o
 obj-$(CONFIG_RTC_DRV_RK808)	+= rtc-rk808.o
 obj-$(CONFIG_RTC_DRV_RP5C01)	+= rtc-rp5c01.o
 obj-$(CONFIG_RTC_DRV_RS5C313)	+= rtc-rs5c313.o