diff --git a/include/drivers/allwinner/axp.h b/include/drivers/allwinner/axp.h
index 9c0035f..222820b 100644
--- a/include/drivers/allwinner/axp.h
+++ b/include/drivers/allwinner/axp.h
@@ -9,6 +9,10 @@
 
 #include <stdint.h>
 
+#define AXP20X_MODE_REG 0x3e
+#define AXP20X_MODE_I2C 0x00
+#define AXP20X_MODE_RSB 0x7c
+
 #define NA 0xff
 
 enum {
diff --git a/plat/allwinner/sun50i_a64/sunxi_power.c b/plat/allwinner/sun50i_a64/sunxi_power.c
index 8aa610c..80a69c3 100644
--- a/plat/allwinner/sun50i_a64/sunxi_power.c
+++ b/plat/allwinner/sun50i_a64/sunxi_power.c
@@ -97,11 +97,8 @@
 	if (ret)
 		return ret;
 
-	/*
-	 * Initiate an I2C transaction to write 0x7c into register 0x3e,
-	 * switching the PMIC to RSB mode.
-	 */
-	ret = rsb_set_device_mode(0x7c3e00);
+	/* Initiate an I2C transaction to switch the PMIC to RSB mode. */
+	ret = rsb_set_device_mode(AXP20X_MODE_RSB << 16 | AXP20X_MODE_REG << 8);
 	if (ret)
 		return ret;
 
@@ -151,6 +148,11 @@
 		pmic = AXP803_RSB;
 		axp_setup_regulators(fdt);
 
+		/* Switch the PMIC back to I2C mode. */
+		ret = axp_write(AXP20X_MODE_REG, AXP20X_MODE_I2C);
+		if (ret)
+			return ret;
+
 		break;
 	default:
 		return -ENODEV;