samples: DFU over Bluetooth SMP rework

docs/includes/matter_extension_activation.txt

@@ -26,4 +26,6 @@ To produce a size-optimized release build (no logging, console or shell), add :f
 
 Use ``nrf54lm20dk/nrf54lm20b/cpuapp`` as the board target for the nRF54LM20B SoC variant.
 
+.. include:: /includes/matter_extension_bt_dfu.txt
+
 See |sample matter limitations ref| for supported board targets and incompatible options.

docs/includes/matter_extension_bt_dfu.txt

@@ -0,0 +1,15 @@
+Device firmware upgrade over Bluetooth SMP
+------------------------------------------
+
+You can update your device's firmware over the air using two methods, both enabled by default in the Matter extension builds:
+
+* Matter OTA – Updates your device through MCUboot, satisfying the Matter specification's requirement to support at least one over-the-air software update method.
+
+* Device Firmware Upgrade (DFU) over Bluetooth LE – Updates your device using the `Simple Management Protocol`_ (SMP).
+  To enable this method, select the :file:`prj_matter_fota.conf` configuration by setting the  ``FILE_SUFFIX=matter_fota`` option.
+
+Matter OTA and SMP DFU are independent transports.
+SMP is not part of the Matter specification.
+Use `mcumgr`_ or `nRF Connect Device Manager`_ to perform the update.
+
+For step-by-step instructions on testing the update process, see |sample matter bt dfu testing ref|.

docs/includes/matter_extension_bt_dfu_testing.txt

@@ -0,0 +1,49 @@
+To test DFU over Bluetooth LE SMP, complete the following steps:
+
+1. Build and flash the sample with the Matter extension (see |sample matter activating variants ref|).
+#. Confirm the device is running the Matter stack (see |sample matter testing ref|).
+#. Briefly press **Button 0** to start Bluetooth LE advertising for SMP.
+
+   The behavior depends on the device's commissioning state:
+
+   * If the device is not commissioned to a Matter fabric, this starts both Matter commissioning advertising and the SMP server.
+   * If the device is already commissioned, this re-enables only the SMP server for firmware transfer.
+
+   **LED 0** blinks while Bluetooth LE advertising for SMP is active.
+   The advertised device name is |bt device name|, set by the ``CONFIG_BT_DEVICE_NAME`` Kconfig option  in the :file:`prj_matter_fota.conf` file.
+
+#. Perform the update using one of the following methods:
+
+   .. tabs::
+
+      .. group-tab:: Smartphone
+
+         a. Install `nRF Connect Device Manager`_.
+         #. Use the :file:`dfu_application.zip` file from the build directory.
+
+         For detailed instructions, see `FOTA updates on nRF54L Series devices`_ (nRF54L15 and nRF54LM20 DKs) or `FOTA updates with nRF5340 DK`_ (nRF5340 DK) depending on the device you are using.
+
+      .. group-tab:: PC (mcumgr)
+
+         Upload the signed images from the build directory:
+
+         * On single-core SoCs (for example, nRF54L Series), upload the application image:
+
+           .. parsed-literal::
+              :class: highlight
+
+              |matter mcumgr smp upload|
+
+         * On dual-core SoCs (for example, nRF5340 DK), upload the application and network core images separately:
+
+           .. parsed-literal::
+              :class: highlight
+
+              |matter mcumgr smp upload|
+
+              |matter mcumgr net smp upload|
+
+         After uploading, list the images, mark each new slot as pending, and reset the device.
+         For the full procedure, see `Performing Device Firmware Upgrade in the nRF Connect examples`_.
+
+After the update completes, MCUboot applies the new image on the next reboot.

docs/includes/zigbee_bt_dfu_activation.txt

@@ -0,0 +1,39 @@
+Activating optional extensions
+------------------------------
+
+To activate the :ref:`lib_zigbee_fota`, use the :file:`prj_fota.conf` configuration file together with the ``zigbee_fota_ext_flash`` snippet.
+The snippet provides external-flash partition layouts, sysbuild MCUboot settings, and the matching MCUboot configuration (through ``zigbee_fota_mcuboot_ext_flash``).
+For example, when building from the command line, use the following command:
+
+.. parsed-literal::
+   :class: highlight
+
+   west build |sample dir| -b *board_target* -- -DFILE_SUFFIX=fota -DSNIPPET=zigbee_fota_ext_flash
+
+The FOTA variant enables `MCUboot image compression`_.
+The generated Zigbee update file contains a compressed MCUboot image, and MCUboot decompresses it while applying the update.
+This setting reduces the size of the update image.
+However, it requires MCUboot to run in overwrite-only mode, which means the device cannot revert to the previous image after an update is applied.
+
+Alternatively, you can :ref:`configure Zigbee FOTA manually <ug_zigbee_configuring_components_ota>`.
+
+.. note::
+   The decompression support increases the size of the MCUboot image.
+   When adapting this FOTA configuration to a custom board or application, make sure that the MCUboot partition is large enough for the generated bootloader image.
+   The FOTA variant uses devicetree-based partitioning with Partition Manager disabled; see :ref:`zigbee_ug_static_partition` for the partition layout requirements.
+
+Device firmware upgrade over Bluetooth SMP (Zigbee-only builds)
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+To additionally enable Device Firmware Upgrade (DFU) over Bluetooth LE using the Simple Management Protocol (SMP) in a Zigbee-only build, add ``CONFIG_ZIGBEE_BT_DFU=y`` to the FOTA build command:
+
+.. parsed-literal::
+   :class: highlight
+
+   west build |sample dir| -b *board_target* -- -DFILE_SUFFIX=fota -DSNIPPET=zigbee_fota_ext_flash -DCONFIG_ZIGBEE_BT_DFU=y
+
+This option enables the MCUmgr SMP server over Bluetooth LE alongside :ref:`lib_zigbee_fota`.
+It cannot be combined with the |sample matter ref| (``CONFIG_CHIP``).
+For Matter extension builds, SMP DFU is provided through ``CONFIG_CHIP_DFU_OVER_BT_SMP`` instead.
+
+See |sample zigbee bt dfu testing ref| for step-by-step testing instructions.

docs/includes/zigbee_bt_dfu_testing.txt

@@ -0,0 +1,36 @@
+To test DFU over Bluetooth SMP in a Zigbee-only build, complete the following steps:
+
+1. Build and flash the sample with the ``CONFIG_ZIGBEE_BT_DFU=y`` Kconfig option (see |sample activating variants ref|).
+#. Wait for the device to boot.
+
+   After booting, the device automatically starts Bluetooth LE connectable advertising for the SMP server.
+   The advertised device name is |zigbee bt device name|, set by ``CONFIG_BT_DEVICE_NAME`` when ``CONFIG_ZIGBEE_BT_DFU`` is enabled.
+
+#. Perform the update using one of the following methods:
+
+   .. tabs::
+
+      .. group-tab:: Smartphone
+
+         a. Install `nRF Connect Device Manager`_.
+         #. Use the :file:`dfu_application.zip` file from the build directory.
+
+         For detailed instructions, see `FOTA updates on nRF54L Series devices`_ (nRF54L15 and nRF54LM20 DKs) or `FOTA updates with nRF5340 DK`_ (nRF5340 DK).
+
+      .. group-tab:: PC (mcumgr)
+
+         Upload the signed application image from the build directory:
+
+         .. parsed-literal::
+            :class: highlight
+
+            |zigbee mcumgr smp upload|
+
+         After uploading, list the images, mark the new slot as pending, and reset the device.
+         For the full procedure (image upload, list, test, and reset), see the `MCUmgr Command-line tool`_ page.
+
+After the update completes, MCUboot applies the new image on the next reboot.
+
+.. note::
+   Zigbee OTA and SMP DFU are independent transports, and SMP is not part of the Zigbee specification.
+   You can use either `mcumgr`_ or `nRF Connect Device Manager`_ to perform the update over Bluetooth LE.

docs/links.txt

@@ -48,6 +48,13 @@
 .. _`Release notes for the nRF Connect SDK`: https://docs.nordicsemi.com/bundle/ncs-3.2.0/page/nrf/releases_and_maturity/release_notes.html
 
 .. _`CHIP Tool`: https://docs.nordicsemi.com/bundle/ncs-3.2.0/page/matter/chip_tool_guide.html
+.. _`mcumgr`: https://docs.nordicsemi.com/bundle/ncs-3.2.0/page/zephyr/services/device_mgmt/mcumgr.html
+.. _`Simple Management Protocol`: https://docs.nordicsemi.com/bundle/ncs-3.2.0/page/zephyr/services/device_mgmt/smp_protocol.html
+.. _`nRF Connect Device Manager`: https://www.nordicsemi.com/Products/Development-tools/nrf-connect-device-manager
+.. _`FOTA updates on nRF54L Series devices`: https://docs.nordicsemi.com/bundle/ncs-3.2.0/page/nrf/app_dev/device_guides/nrf54l/fota_update.html
+.. _`FOTA updates with nRF5340 DK`: https://docs.nordicsemi.com/bundle/ncs-3.2.0/page/nrf/app_dev/device_guides/nrf53/fota_update_nrf5340.html
+.. _`MCUmgr Command-line tool`: https://docs.nordicsemi.com/bundle/ncs-3.2.0/page/nrf/app_dev/bootloaders_dfu/dfu_tools_mcumgr_cli.html
+.. _`Performing Device Firmware Upgrade in the nRF Connect examples`: https://docs.nordicsemi.com/bundle/ncs-3.2.0/page/matter/nrfconnect_examples_software_update.html
 
 .. _`DFU over Zigbee`: https://docs.nordicsemi.com/bundle/nrfutil/page/guides-nrf5sdk/dfu_performing.html#dfu-over-zigbee
 

samples/light_bulb/Kconfig

@@ -17,6 +17,13 @@ endchoice
 
 endif # OPENTHREAD
 
+if ZIGBEE_BT_DFU
+
+config BT_DEVICE_NAME
+	default "Zigbee_Bulb"
+
+endif # ZIGBEE_BT_DFU
+
 config MPSL_THREAD_COOP_PRIO
 	default 8
 

samples/light_bulb/Kconfig.sysbuild

@@ -20,4 +20,39 @@ endchoice
 
 endif # MATTER
 
+if BOOTLOADER_MCUBOOT
+
+#### DFU multi-image support
+config DFU_MULTI_IMAGE_PACKAGE_BUILD
+	default y
+
+config DFU_MULTI_IMAGE_PACKAGE_APP
+	default y
+
+#### DFU dual core configuration
+if SOC_SERIES_NRF53
+
+config PM_EXTERNAL_FLASH_MCUBOOT_SECONDARY
+	default y
+
+config MCUBOOT_UPDATEABLE_IMAGES
+	default 2
+
+choice MCUBOOT_MODE
+	default MCUBOOT_MODE_OVERWRITE_ONLY
+endchoice
+
+config SECURE_BOOT_NETCORE
+	default y
+
+config NETCORE_APP_UPDATE
+	default y
+
+config DFU_MULTI_IMAGE_PACKAGE_NET
+	default y
+
+endif # SOC_SERIES_NRF53
+
+endif # BOOTLOADER_MCUBOOT
+
 source "${ZEPHYR_BASE}/share/sysbuild/Kconfig"

samples/light_bulb/README.rst

@@ -82,6 +82,17 @@ Configuration
 
 |config|
 
+Source file setup
+=================
+
+This sample is split into the following source files:
+
+* The :file:`main` file is the application entry point only.
+* The :file:`app_task_zigbee` file manages the application task flow, user input handling, and Zigbee-specific startup and control logic.
+  It also implements the dimmable light device behavior, including cluster handling and PWM-based brightness control.
+* The :file:`app_task_matter` file is used in the Matter extension build only.
+  It implements the Matter application task flow, button input, and On/Off and Level Control cluster state for the dimmable light endpoint.
+
 ..
   FEM support
   ===========
@@ -93,10 +104,20 @@ Configuration
 Configuration files for sample extensions
 =========================================
 
+The sample provides predefined configuration files for optional extensions.
+You can find the configuration files in the :file:`samples/light_bulb` directory.
+
 .. |sample matter ref| replace:: :ref:`zigbee_light_bulb_sample_matter`
 .. |sample matter limitations ref| replace:: :ref:`zigbee_light_bulb_matter_limitations`
+.. |sample matter bt dfu testing ref| replace:: :ref:`zigbee_light_bulb_testing_matter_bt_dfu`
+.. |sample matter testing ref| replace:: :ref:`zigbee_light_bulb_testing_matter`
+.. |sample matter activating variants ref| replace:: :ref:`zigbee_light_bulb_activating_variants`
+.. |sample activating variants ref| replace:: :ref:`zigbee_light_bulb_activating_variants`
+.. |sample zigbee bt dfu testing ref| replace:: :ref:`zigbee_light_bulb_testing_zigbee_bt_dfu`
 .. |sample dir| replace:: samples/light_bulb
 
+.. include:: /includes/zigbee_bt_dfu_activation.txt
+
 .. include:: /includes/matter_extension_activation.txt
 
 User interface
@@ -263,6 +284,28 @@ Complete the following steps to exercise the full Zigbee-to-Matter flow:
    * Or trigger a Matter factory reset from the controller (for example, ``chip-tool pairing unpair …``).
      The device reboots as a fresh Zigbee Router with Matter Bluetooth LE advertising active again, and Matter storage is cleared.
 
+.. _zigbee_light_bulb_testing_matter_bt_dfu:
+
+Testing Matter extension DFU over Bluetooth SMP
+-----------------------------------------------
+
+.. |bt device name| replace:: MatterZigbeeLb
+.. |app name| replace:: light_bulb
+.. |matter mcumgr smp upload| replace:: mcumgr --conntype ble --hci 0 --connstring peer_name='MatterZigbeeLb' image upload build/light_bulb/zephyr/zephyr.signed.bin -n 0 -w 1
+.. |matter mcumgr net smp upload| replace:: mcumgr --conntype ble --hci 0 --connstring peer_name='MatterZigbeeLb' image upload build/signed_by_mcuboot_and_b0_ipc_radio.bin -n 1 -w 1
+
+.. include:: /includes/matter_extension_bt_dfu_testing.txt
+
+.. _zigbee_light_bulb_testing_zigbee_bt_dfu:
+
+Testing Zigbee FOTA DFU over Bluetooth SMP
+------------------------------------------
+
+.. |zigbee bt device name| replace:: Zigbee_Bulb
+.. |zigbee mcumgr smp upload| replace:: mcumgr --conntype ble --hci 0 --connstring peer_name='Zigbee_Bulb' image upload build/light_bulb/zephyr/zephyr.signed.bin
+
+.. include:: /includes/zigbee_bt_dfu_testing.txt
+
 Dependencies
 ************
 

samples/light_bulb/boards/nrf52840dk_nrf52840_fota.overlay

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2026 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#include <nrf52840_partitions.dtsi>
+#include <ext_flash/nrf52840dk_partitions.dtsi>
+
+/ {
+	pwmleds {
+		pwm_led3: pwm_led_3 {
+			pwms = <&pwm0 1 PWM_MSEC(20) PWM_POLARITY_INVERTED>;
+		};
+	};
+
+	chosen {
+		ncs,zigbee-timer = &timer2;
+	};
+};
+
+&pwm0 {
+	pinctrl-0 = <&pwm0_default_alt>;
+	pinctrl-1 = <&pwm0_sleep_alt>;
+	pinctrl-names = "default", "sleep";
+};
+
+&pinctrl {
+	pwm0_default_alt: pwm0_default_alt {
+		group1 {
+			psels = <NRF_PSEL(PWM_OUT1, 0, 16)>;
+			nordic,invert;
+		};
+	};
+
+	pwm0_sleep_alt: pwm0_sleep_alt {
+		group1 {
+			psels = <NRF_PSEL(PWM_OUT1, 0, 16)>;
+			low-power-enable;
+		};
+	};
+};
+
+&timer2 {
+	status = "okay";
+};

samples/light_bulb/boards/nrf5340dk_nrf5340_cpuapp_fota.overlay

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2026 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#include <nrf5340_cpuapp_partitions.dtsi>
+#include <ext_flash/nrf5340dk_cpuapp_partitions.dtsi>
+
+/ {
+	pwmleds {
+		compatible = "pwm-leds";
+
+		pwm_led3: pwm_led_3 {
+			pwms = <&pwm0 1 PWM_MSEC(20) PWM_POLARITY_INVERTED>;
+		};
+	};
+
+	chosen {
+		ncs,zigbee-timer = &timer2;
+	};
+};
+
+&pwm0 {
+	status = "okay";
+	pinctrl-0 = <&pwm0_default_alt>;
+	pinctrl-1 = <&pwm0_sleep_alt>;
+	pinctrl-names = "default", "sleep";
+};
+
+&pinctrl {
+	pwm0_default_alt: pwm0_default_alt {
+		group1 {
+			psels = <NRF_PSEL(PWM_OUT1, 0, 31)>;
+			nordic,invert;
+		};
+	};
+
+	pwm0_sleep_alt: pwm0_sleep_alt {
+		group1 {
+			psels = <NRF_PSEL(PWM_OUT1, 0, 31)>;
+			low-power-enable;
+		};
+	};
+};
+
+&timer2 {
+	status = "okay";
+};

samples/light_bulb/boards/nrf54l15dk_nrf54l10_cpuapp_fota.overlay

@@ -0,0 +1,8 @@
+/*
+ * Copyright (c) 2026 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#include <nrf54l10_cpuapp_partitions.dtsi>
+#include <ext_flash/nrf54l10dk_cpuapp_partitions.dtsi>