overlays: Add rv3028 to i2c-rtc

See: #2912

Signed-off-by: Phil Elwell <[email protected]>

Author: Phil Elwell

arch/arm/boot/dts/overlays/README

@@ -939,6 +939,8 @@ Params: abx80x                  Select one of the ABx80x family:
 
         pcf8563                 Select the PCF8563 device
 
+        rv3028                  Select the Micro Crystal RV3028 device
+
         addr                    Sets the address for the RTC. Note that the
                                 device must be configured to use the specified
                                 address.
@@ -947,7 +949,7 @@ Params: abx80x                  Select one of the ABx80x family:
                                 "schottky" (ABx80x only)
 
         trickle-resistor-ohms   Resistor value for trickle charge (DS1339,
-                                ABx80x)
+                                ABx80x, RV3028)
 
         wakeup-source           Specify that the RTC can be used as a wakeup
                                 source

arch/arm/boot/dts/overlays/i2c-rtc-overlay.dts

@@ -158,6 +158,21 @@
 		};
 	};
 
+	fragment@10 {
+		target = <&i2c_arm>;
+		__dormant__ {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			status = "okay";
+
+			rv3028: rv3028@52 {
+				compatible = "microcrystal,rv3028";
+				reg = <0x52>;
+				status = "okay";
+			};
+		};
+	};
+
 	__overrides__ {
 		abx80x = <0>,"+0";
 		ds1307 = <0>,"+1";
@@ -169,6 +184,7 @@
 		pcf8523 = <0>,"+7";
 		pcf8563 = <0>,"+8";
 		m41t62 = <0>,"+9";
+		rv3028 = <0>,"+10";
 
 		addr = <&abx80x>, "reg:0",
 		       <&ds1307>, "reg:0",
@@ -182,7 +198,8 @@
 		       <&m41t62>, "reg:0";
 		trickle-diode-type = <&abx80x>,"abracon,tc-diode";
 		trickle-resistor-ohms = <&ds1339>,"trickle-resistor-ohms:0",
-					<&abx80x>,"abracon,tc-resistor";
+					<&abx80x>,"abracon,tc-resistor",
+					<&rv3028>,"trickle-resistor-ohms:0";
 		wakeup-source = <&ds1339>,"wakeup-source?",
 				<&ds3231>,"wakeup-source?",
 				<&mcp7940x>,"wakeup-source?",