[PATCH] ARM: dts: witherspoon: add Epson RX8900CE RTC module

[Chris Smart <chris@distroguy.com>]

This commit adds the relevant device tree entry for the Epson RX8900CE
RTC module on the I2C bus.

Note that there are two options that we may need to set.

If there is no connected battery:
 epson,vdet-disable;

If there is no trickle charge diode:
 epson,vdet-disable;

These are currently left commented out in the commit.

Signed-off-by: Chris Smart <chris@distroguy.com>
---
 arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts b/arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts
index 328a9c4e189e..679d360272cc 100644
--- a/arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts
+++ b/arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts
@@ -148,7 +148,18 @@
 
 	/* TPM */
 	/* 9552 */
+
 	/* RTC */
+	rtc: rtc@32 {
+		compatible = "epson,rx8900"
+		reg = <0x32>;
+		/* If no battery, set this:
+		 * epson,vdet-disable;
+		 * If no trickle charge diode, set this:
+		 * epson,vdet-disable;
+		 */
+	};
+
 	/* EEPROM */
 
 	eeprom@51 {
-- 
2.9.3