diff --git a/drivers/serial/uart_ns16550.c b/drivers/serial/uart_ns16550.c
index f2d4144fa61..62e56500557 100644
--- a/drivers/serial/uart_ns16550.c
+++ b/drivers/serial/uart_ns16550.c
@@ -197,8 +197,8 @@
 
 #define IIRC(dev) (DEV_DATA(dev)->iir_cache)
 
-#ifdef CONFIG_NS16550_REG_SHIFT
-#define UART_REG_ADDR_INTERVAL (1<<CONFIG_NS16550_REG_SHIFT)
+#ifdef DT_NS16550_REG_SHIFT
+#define UART_REG_ADDR_INTERVAL (1<<DT_NS16550_REG_SHIFT)
 #endif
 
 #ifdef UART_NS16550_ACCESS_IOPORT
diff --git a/soc/arm/microchip_mec/mec1701/dts_fixup.h b/soc/arm/microchip_mec/mec1701/dts_fixup.h
index 649ac0a3ced..1e0699ff89e 100644
--- a/soc/arm/microchip_mec/mec1701/dts_fixup.h
+++ b/soc/arm/microchip_mec/mec1701/dts_fixup.h
@@ -6,7 +6,7 @@
 
 
 #define DT_NUM_IRQ_PRIO_BITS			DT_ARM_V7M_NVIC_E000E100_ARM_NUM_IRQ_PRIORITY_BITS
-#define CONFIG_NS16550_REG_SHIFT		DT_NS16550_400F2400_REG_SHIFT
+#define DT_NS16550_REG_SHIFT			DT_NS16550_400F2400_REG_SHIFT
 #define DT_UART_NS16550_PORT_0_BASE_ADDR	DT_NS16550_400F2400_BASE_ADDRESS
 #define DT_UART_NS16550_PORT_0_CLK_FREQ		1843200
 #define DT_UART_NS16550_PORT_0_NAME		DT_NS16550_400F2400_LABEL