rtc: Add Cadence RTC driver

This patch adds a driver for Cadence RTC controller.

It can be enabled with RTC_DRV_CADENCE Kconfig option.
It supports waking system from sleep modes.

Signed-off-by: Jan Kotas <jank@cadence.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index a24fe8b..faa9ae1 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -1517,6 +1517,16 @@
 	  This driver can also be built as a module. If so, the module
 	  will be called armada38x-rtc.
 
+config RTC_DRV_CADENCE
+	tristate "Cadence RTC driver"
+	depends on OF && HAS_IOMEM
+	help
+	  If you say Y here you will get access to Cadence RTC IP
+	  found on certain SOCs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called rtc-cadence.
+
 config RTC_DRV_FTRTC010
 	tristate "Faraday Technology FTRTC010 RTC"
 	depends on HAS_IOMEM