subsys: added support for DFU over Bluetooth LE SMP

Created a new Kconfig module that provides support for DFU
over BLuetooth LE for Zigbee-only solution.

Signed-off-by: Kamil Kasperczyk <kamil.kasperczyk@nordicsemi.no>

Author: kkasperczyk-no

include/zigbee/zigbee_bt_dfu.h

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2026 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+/**
+ * @file zigbee_bt_dfu.h
+ *
+ * @brief DFU over Bluetooth LE SMP helpers for Zigbee applications.
+ */
+
+#ifndef ZIGBEE_BT_DFU_H_
+#define ZIGBEE_BT_DFU_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void zigbee_bt_dfu_init(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* ZIGBEE_BT_DFU_H_ */

samples/light_switch/Kconfig

@@ -57,3 +57,10 @@ config LIGHT_SWITCH_LOW_POWER
 	help
 		Enable low power mode for the Light Switch sample.
 		This enables sleepy behavior and disables LEDs for power savings.
+
+if ZIGBEE_BT_DFU
+
+config BT_DEVICE_NAME
+	default "Zigbee_Switch"
+
+endif # ZIGBEE_BT_DFU

samples/light_switch/sample.yaml

@@ -35,6 +35,23 @@ tests:
       - smoke
       - sysbuild
       - ci_samples_zigbee
+  sample.zigbee.light_switch.matter.bt_dfu:
+    sysbuild: true
+    build_only: true
+    extra_args:
+      - FILE_SUFFIX=matter_fota
+      - CONFIG_CHIP_DFU_OVER_BT_SMP=y
+    integration_platforms:
+      - nrf54lm20dk/nrf54lm20a/cpuapp
+      - nrf54lm20dk/nrf54lm20b/cpuapp
+    platform_allow:
+      - nrf54lm20dk/nrf54lm20a/cpuapp
+      - nrf54lm20dk/nrf54lm20b/cpuapp
+    tags:
+      - ci_build
+      - smoke
+      - sysbuild
+      - ci_samples_zigbee
   sample.zigbee.light_switch:
     sysbuild: true
     build_only: true
@@ -148,6 +165,31 @@ tests:
       - smoke
       - sysbuild
       - ci_samples_zigbee
+  sample.zigbee.light_switch.fota_and_bt_dfu:
+    sysbuild: true
+    build_only: true
+    extra_args:
+      - FILE_SUFFIX=fota
+      - CONFIG_ZIGBEE_BT_DFU=y
+    integration_platforms:
+      - nrf52840dk/nrf52840
+      - nrf5340dk/nrf5340/cpuapp
+      - nrf54l15dk/nrf54l10/cpuapp
+      - nrf54l15dk/nrf54l15/cpuapp
+      - nrf54lm20dk/nrf54lm20a/cpuapp
+      - nrf54lm20dk/nrf54lm20b/cpuapp
+    platform_allow:
+      - nrf52840dk/nrf52840
+      - nrf5340dk/nrf5340/cpuapp
+      - nrf54l15dk/nrf54l10/cpuapp
+      - nrf54l15dk/nrf54l15/cpuapp
+      - nrf54lm20dk/nrf54lm20a/cpuapp
+      - nrf54lm20dk/nrf54lm20b/cpuapp
+    tags:
+      - ci_build
+      - smoke
+      - sysbuild
+      - ci_samples_zigbee
   sample.zigbee.light_switch.low_power:
     sysbuild: true
     build_only: true

samples/light_switch/src/app_task_zigbee.c

@@ -38,12 +38,21 @@
 #if CONFIG_ZIGBEE_FOTA
 #include <zigbee/zigbee_fota.h>
 #include <zephyr/sys/reboot.h>
+#endif /* CONFIG_ZIGBEE_FOTA */
+
+#if defined(CONFIG_ZIGBEE_FOTA) || defined(CONFIG_ZIGBEE_BT_DFU)
 #include <zephyr/dfu/mcuboot.h>
+#endif
 
+#if CONFIG_ZIGBEE_FOTA
 /* LED indicating OTA Client Activity. */
 #define OTA_ACTIVITY_LED          DK_LED2
 #endif /* CONFIG_ZIGBEE_FOTA */
 
+#ifdef CONFIG_ZIGBEE_BT_DFU
+#include <zigbee/zigbee_bt_dfu.h>
+#endif
+
 #if CONFIG_BT_NUS
 #include "nus_cmd.h"
 
@@ -642,7 +651,7 @@ static void light_switch_button_handler(struct k_timer *timer)
 	}
 }
 
-#ifdef CONFIG_ZIGBEE_FOTA
+#if defined(CONFIG_ZIGBEE_FOTA) || defined(CONFIG_ZIGBEE_BT_DFU)
 static void confirm_image(void)
 {
 	if (!boot_is_img_confirmed()) {
@@ -655,7 +664,9 @@ static void confirm_image(void)
 		}
 	}
 }
+#endif
 
+#ifdef CONFIG_ZIGBEE_FOTA
 static void ota_evt_handler(const struct zigbee_fota_evt *evt)
 {
 	switch (evt->id) {
@@ -959,17 +970,23 @@ int ZigbeeStart(void)
 		power_down_unused_ram();
 	}
 
+#if defined(CONFIG_ZIGBEE_FOTA) || defined(CONFIG_ZIGBEE_BT_DFU)
+	/* Mark the current firmware as valid. */
+	confirm_image();
+#endif
+
 #ifdef CONFIG_ZIGBEE_FOTA
 	/* Initialize Zigbee FOTA download service. */
 	zigbee_fota_init(ota_evt_handler);
 
-	/* Mark the current firmware as valid. */
-	confirm_image();
-
 	/* Register callback for handling ZCL commands. */
 	ZB_ZCL_REGISTER_DEVICE_CB(zcl_device_cb);
 #endif /* CONFIG_ZIGBEE_FOTA */
 
+#ifdef CONFIG_ZIGBEE_BT_DFU
+	zigbee_bt_dfu_init();
+#endif
+
 	/* Register dimmer switch device context (endpoints). */
 	ZB_AF_REGISTER_DEVICE_CTX(&dimmer_switch_ctx);
 

samples/light_switch/src/main.cpp

@@ -17,7 +17,7 @@
 
 #ifdef CONFIG_ZIGBEE_MATTER_COEXISTENCE
 
-#include "app_task.h"
+#include "app_task_matter.h"
 
 #include <zigbee/matter_coexistence.h>
 

subsys/lib/CMakeLists.txt

@@ -5,6 +5,7 @@
 #
 
 add_subdirectory_ifdef(CONFIG_ZIGBEE_FOTA zigbee_fota)
+add_subdirectory_ifdef(CONFIG_ZIGBEE_BT_DFU zigbee_bt_dfu)
 add_subdirectory_ifdef(CONFIG_ZIGBEE_APP_UTILS zigbee_app_utils)
 add_subdirectory_ifdef(CONFIG_ZIGBEE_LOGGER_EP zigbee_logger_ep)
 add_subdirectory_ifdef(CONFIG_ZIGBEE_MATTER_COEXISTENCE zigbee_matter_coexistence)

subsys/lib/Kconfig

@@ -6,6 +6,7 @@
 menu "Zigbee libraries"
 
 rsource "zigbee_fota/Kconfig"
+rsource "zigbee_bt_dfu/Kconfig"
 rsource "zigbee_app_utils/Kconfig"
 rsource "zigbee_logger_ep/Kconfig"
 rsource "zigbee_matter_coexistence/Kconfig"

subsys/lib/zigbee_bt_dfu/CMakeLists.txt

@@ -0,0 +1,10 @@
+#
+# Copyright (c) 2026 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+zephyr_library()
+zephyr_library_sources(zigbee_bt_dfu.c)
+
+zephyr_library_link_libraries(MCUBOOT_BOOTUTIL)

subsys/lib/zigbee_bt_dfu/Kconfig

@@ -0,0 +1,88 @@
+#
+# Copyright (c) 2026 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+config ZIGBEE_BT_DFU
+	bool "Enable DFU over Bluetooth LE SMP feature set"
+	depends on !CHIP
+	select BOOTLOADER_MCUBOOT
+	select BT
+	select BT_PERIPHERAL
+	select MCUMGR
+	select MCUMGR_TRANSPORT_BT
+	select IMG_MANAGER
+	select STREAM_FLASH
+	select ZCBOR
+	select MCUMGR_GRP_IMG
+	select MCUMGR_GRP_OS
+	select MCUMGR_GRP_IMG_STATUS_HOOKS
+	# Enable custom SMP request to erase settings partition.
+	select MCUMGR_GRP_ZBASIC
+	select MCUMGR_GRP_ZBASIC_STORAGE_ERASE
+	select MCUMGR_TRANSPORT_BT_REASSEMBLY
+	help
+	  Enables Device Firmware Upgrade over Bluetooth LE with SMP and configures
+	  the set of options related to that feature.
+
+	  Cannot be combined with Matter (CONFIG_CHIP), as it requires different Bluetooth LE orchestration.
+	  Use Matter's CONFIG_CHIP_DFU_OVER_BT_SMP instead.
+
+if ZIGBEE_BT_DFU
+
+config BT_MAX_CONN
+	default 1
+
+# MCU Manager and SMP configuration
+choice MCUMGR_TRANSPORT_BT_PERM
+	default MCUMGR_TRANSPORT_BT_PERM_RW
+endchoice
+		
+config MCUMGR_TRANSPORT_NETBUF_COUNT
+	default 6
+
+config MCUMGR_MGMT_NOTIFICATION_HOOKS
+	bool
+	default y
+		
+config MCUMGR_GRP_IMG_UPLOAD_CHECK_HOOK
+	bool
+	default y
+		
+config MCUMGR_SMP_COMMAND_STATUS_HOOKS
+	bool
+	default y
+		
+# Increase BT MTU and RX buffer sizes to improve DFU throughput
+config BT_L2CAP_TX_MTU
+	default 498
+		
+config BT_BUF_ACL_RX_SIZE
+	default 502
+		
+# Increase MCUMGR_TRANSPORT_NETBUF_SIZE, as it must be big enough to fit MAX MTU + overhead and for single-image DFU default is 384 B
+config MCUMGR_TRANSPORT_NETBUF_SIZE
+	default 1024
+		
+# Increase system workqueue size, as SMP is processed within it
+config SYSTEM_WORKQUEUE_STACK_SIZE
+	default 2800
+		
+if SOC_SERIES_NRF53
+		
+# Enable custom SMP request to erase settings partition.
+config MCUMGR_GRP_ZBASIC
+	default y
+		
+config MCUMGR_GRP_ZBASIC_STORAGE_ERASE
+	default y
+		
+endif # SOC_SERIES_NRF53
+
+module = ZIGBEE_BT_DFU
+module-str = Zigbee Bluetooth LE DFU
+source "${ZEPHYR_BASE}/subsys/logging/Kconfig.template.log_config"
+
+endif # ZIGBEE_BT_DFU
+