diff --git a/examples/zephyr_example/boards/esp32_devkitc_wrover.overlay b/examples/zephyr_example/boards/esp32_devkitc_wrover.overlay
deleted file mode 100644
index c028c9d..0000000
--- a/examples/zephyr_example/boards/esp32_devkitc_wrover.overlay
+++ /dev/null
@@ -1,34 +0,0 @@
-/*
- * Copyright (c) 2022 Espressif Systems (Shanghai) Co., Ltd.
- *
- * SPDX-License-Identifier: Apache-2.0
- */
-
-#include <zephyr/dt-bindings/pinctrl/esp-pinctrl-common.h>
-#include <dt-bindings/pinctrl/esp32-pinctrl.h>
-#include <zephyr/dt-bindings/pinctrl/esp32-gpio-sigmap.h>
-
-/ {
-	aliases {
-		en = &en_button;
-		boot = &boot_button;
-		uart = &uart1;
-	};
-
-	gpio_keys {
-		compatible = "gpio-keys";
-		en_button: en_button {
-			gpios = <&gpio0 2 (GPIO_PULL_UP | GPIO_ACTIVE_HIGH)>;
-		};
-		boot_button: boot_button {
-			gpios = <&gpio0 4 (GPIO_PULL_UP | GPIO_ACTIVE_HIGH)>;
-		};
-	};
-};
-
-&uart1 {
-	status = "okay";
-	current-speed = <115200>;
-	pinctrl-0 = <&uart1_default>;
-	pinctrl-names = "default";
-};
diff --git a/examples/zephyr_example/boards/esp32_devkitc_wroom.overlay b/examples/zephyr_example/socs/esp32_procpu.overlay
similarity index 55%
rename from examples/zephyr_example/boards/esp32_devkitc_wroom.overlay
rename to examples/zephyr_example/socs/esp32_procpu.overlay
index c028c9d..b4e9a7e 100644
--- a/examples/zephyr_example/boards/esp32_devkitc_wroom.overlay
+++ b/examples/zephyr_example/socs/esp32_procpu.overlay
@@ -1,13 +1,9 @@
 /*
- * Copyright (c) 2022 Espressif Systems (Shanghai) Co., Ltd.
+ * Copyright (c) 2024 Espressif Systems (Shanghai) Co., Ltd.
  *
  * SPDX-License-Identifier: Apache-2.0
  */
 
-#include <zephyr/dt-bindings/pinctrl/esp-pinctrl-common.h>
-#include <dt-bindings/pinctrl/esp32-pinctrl.h>
-#include <zephyr/dt-bindings/pinctrl/esp32-gpio-sigmap.h>
-
 / {
 	aliases {
 		en = &en_button;
@@ -28,7 +24,4 @@
 
 &uart1 {
 	status = "okay";
-	current-speed = <115200>;
-	pinctrl-0 = <&uart1_default>;
-	pinctrl-names = "default";
 };
diff --git a/examples/zephyr_example/src/main.c b/examples/zephyr_example/src/main.c
index ad6afad..f515411 100644
--- a/examples/zephyr_example/src/main.c
+++ b/examples/zephyr_example/src/main.c
@@ -45,17 +45,17 @@ int main(void)
 
     if (!device_is_ready(esp_uart_dev)) {
         printk("ESP UART not ready");
-        return;
+        return -ENODEV;
     }
 
     if (!device_is_ready(esp_boot_spec.port)) {
         printk("ESP boot GPIO not ready");
-        return;
+        return -ENODEV;
     }
 
     if (!device_is_ready(esp_enable_spec.port)) {
-        printk("Bluetooth Enable GPIO not ready");
-        return;
+        printk("ESP enable GPIO not ready");
+        return -ENODEV;
     }
 
     gpio_pin_configure_dt(&esp_boot_spec, GPIO_OUTPUT_ACTIVE);
@@ -63,7 +63,7 @@ int main(void)
 
     if (loader_port_zephyr_init(&config) != ESP_LOADER_SUCCESS) {
         printk("ESP loader init failed");
-        return;
+        return -EIO;
     }
 
     if (connect_to_target(HIGHER_BAUDRATE) == ESP_LOADER_SUCCESS) {
diff --git a/zephyr/CMakeLists.txt b/zephyr/CMakeLists.txt
index 13548ca..031c174 100644
--- a/zephyr/CMakeLists.txt
+++ b/zephyr/CMakeLists.txt
@@ -1,24 +1,26 @@
 cmake_minimum_required(VERSION 3.5)
 
 if (CONFIG_ESP_SERIAL_FLASHER)
-    zephyr_include_directories(
-        "${ZEPHYR_CURRENT_MODULE_DIR}/include"
-        "${ZEPHYR_CURRENT_MODULE_DIR}/port"
-        "${ZEPHYR_CURRENT_MODULE_DIR}/private_include"
-    )
 
     zephyr_interface_library_named(esp_flasher)
 
     zephyr_library()
 
-    zephyr_library_sources(${ZEPHYR_CURRENT_MODULE_DIR}/src/esp_loader.c
-                ${ZEPHYR_CURRENT_MODULE_DIR}/src/esp_targets.c
-                ${ZEPHYR_CURRENT_MODULE_DIR}/src/esp_stubs.c
-                ${ZEPHYR_CURRENT_MODULE_DIR}/src/protocol_common.c
-                ${ZEPHYR_CURRENT_MODULE_DIR}/src/protocol_uart.c
-                ${ZEPHYR_CURRENT_MODULE_DIR}/src/slip.c
-                ${ZEPHYR_CURRENT_MODULE_DIR}/src/md5_hash.c
-                ${ZEPHYR_CURRENT_MODULE_DIR}/port/zephyr_port.c
+    zephyr_include_directories(
+        ${ZEPHYR_CURRENT_MODULE_DIR}/private_include
+        ${ZEPHYR_CURRENT_MODULE_DIR}/include
+        ${ZEPHYR_CURRENT_MODULE_DIR}/port
+    )
+
+    zephyr_library_sources(
+        ${ZEPHYR_CURRENT_MODULE_DIR}/src/esp_loader.c
+        ${ZEPHYR_CURRENT_MODULE_DIR}/port/zephyr_port.c
+        ${ZEPHYR_CURRENT_MODULE_DIR}/src/esp_targets.c
+        ${ZEPHYR_CURRENT_MODULE_DIR}/src/esp_stubs.c
+        ${ZEPHYR_CURRENT_MODULE_DIR}/src/protocol_common.c
+        ${ZEPHYR_CURRENT_MODULE_DIR}/src/protocol_uart.c
+        ${ZEPHYR_CURRENT_MODULE_DIR}/src/slip.c
+        ${ZEPHYR_CURRENT_MODULE_DIR}/src/md5_hash.c
     )
 
     target_compile_definitions(esp_flasher INTERFACE SERIAL_FLASHER_INTERFACE_UART)