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Migration guide to Zephyr v3.7.0

This document describes the changes required when migrating your application from Zephyr v3.6.0 to Zephyr v3.7.0.

Any other changes (not directly related to migrating applications) can be found in the release notes.

Build System

  • Completely overhauled the way SoCs and boards are defined. This requires all out-of-tree SoCs and boards to be ported to the new model. See the Transition to the current hardware model for more detailed information. (GitHub #69607)

  • The following build-time generated headers:

    Affected header files

    app_version.h

    autoconf.h

    cmake_intdef.h

    core-isa-dM.h

    devicetree_generated.h

    driver-validation.h

    kobj-types-enum.h

    linker-kobject-prebuilt-data.h

    linker-kobject-prebuilt-priv-stacks.h

    linker-kobject-prebuilt-rodata.h

    mcuboot_version.h

    offsets.h

    otype-to-size.h

    otype-to-str.h

    strerror_table.h

    strsignal_table.h

    syscall_list.h

    version.h

    zsr.h

    as well as syscall headers & sources are now namespaced into the zephyr/ folder. The change is largely automated, and the script can be found in GitHub #63973. For the time being, the compatibility Kconfig (CONFIG_LEGACY_GENERATED_INCLUDE_PATH) is enabled by default so that downstream applications will continue to compile, a warning message will be generated during CMake configuration time. This Kconfig will be deprecated and eventually removed in the future, developers are advised to update the include paths of these affected headers as soon as possible.

Kernel

  • All architectures are now required to define the new struct arch_esf, which describes the members of a stack frame. This new struct replaces the named struct z_arch_esf_t. (GitHub #73593)

  • The named struct z_arch_esf_t is now deprecated. Use struct arch_esf instead. (GitHub #73593)

  • The header file include/zephyr/arch/arch_interface.h has been moved from include/zephyr/sys/ into include/zephyr/arch/. Out-of-tree source files will need to update the include path. (GitHub #64987)

Boards

  • Reordered D1 and D0 in the pro_micro connector gpio-map for SparkFun Pro Micro RP2040 to match original Pro Micro definition. Out-of-tree shields must be updated to reflect this change. (GitHub #69994)

  • ITE: Rename all SoC variant Kconfig options, e.g., CONFIG_SOC_IT82202_AX is renamed to CONFIG_SOC_IT82202AX. All symbols are renamed as follows: SOC_IT81202BX, SOC_IT81202CX, SOC_IT81302BX, SOC_IT81302CX, SOC_IT82002AW, SOC_IT82202AX, SOC_IT82302AX. And, rename the SOC_SERIES_ITE_IT8XXX2 to SOC_SERIES_IT8XXX2. (GitHub #71680)

  • For native_sim/posix: CONFIG_EMUL is no longer enabled by default when CONFIG_I2C is set. Users who need this setting enabled should set it in their project config file. (GitHub #73067)

  • LiteX: Renamed the compatible of the LiteX VexRiscV interrupt controller node from vexriscv-intc0 to litex,vexriscv-intc0. (GitHub #73211)

  • lairdconnect boards are now ezurio boards. Laird Connectivity has rebranded to Ezurio.

Modules

Mbed TLS

  • TLS 1.2, RSA, AES, DES, and all the hash algorithms except SHA-256 (SHA-224, SHA-384, SHA-512, MD5 and SHA-1) are not enabled by default anymore. Their respective Kconfig options now need to be explicitly enabled to be able to use them. (GitHub #72078)

  • The Kconfig options previously named CONFIG_MBEDTLS_MAC_*_ENABLED have been renamed. The _MAC and _ENABLED parts have been removed from their names. (GitHub #73267)

  • The CONFIG_MBEDTLS_HASH_ALL_ENABLED Kconfig option has been fixed to actually enable all the available hash algorithms. Previously, it used to only enable the SHA-2 ones. (GitHub #73267)

  • The CONFIG_MBEDTLS_HASH_SHA*_ENABLED Kconfig options have been removed. They were duplicates of other Kconfig options which are now named CONFIG_MBEDTLS_SHA*. (GitHub #73267)

  • The CONFIG_MBEDTLS_MAC_ALL_ENABLED Kconfig option has been removed. Its equivalent is the combination of CONFIG_MBEDTLS_HASH_ALL_ENABLED and CONFIG_MBEDTLS_CMAC. (GitHub #73267)

  • The Kconfig options CONFIG_MBEDTLS_MAC_MD4_ENABLED, CONFIG_MBEDTLS_CIPHER_ARC4_ENABLED and CONFIG_MBEDTLS_CIPHER_BLOWFISH_ENABLED were removed because they are no more supported in Mbed TLS. (GitHub #73222)

  • When there is any PSA crypto provider available in the system (i.e. CONFIG_MBEDTLS_PSA_CRYPTO_CLIENT is set), desired PSA crypto features must be explicitly enabled using proper CONFIG_PSA_WANT_*. (GitHub #72243)

  • TLS/X509/PK/MD modules will use PSA crypto APIs instead of legacy ones as soon as there is any PSA crypto provider available in the system (i.e. CONFIG_MBEDTLS_PSA_CRYPTO_CLIENT is set). (GitHub #72243)

Trusted Firmware-M

  • The default MCUboot signature type has been changed from RSA-3072 to EC-P256. This affects builds that have MCUboot enabled in TF-M (CONFIG_TFM_BL2). If you wish to keep using RSA-3072, you need to set CONFIG_TFM_MCUBOOT_SIGNATURE_TYPE to "RSA-3072". Otherwise, make sure to have your own signing keys of the signature type in use.

LVGL

Device Drivers and Devicetree

  • The nxp,kinetis-pit pit driver has changed its compatible to nxp,pit and has been updated to support multiple channels. To configure the individual channels, you must add a child node with the compatible nxp,pit-channel and configure as below. The CONFIG_COUNTER_MCUX_PIT has also been renamed to CONFIG_COUNTER_NXP_PIT with regards to the renaming of the binding for the pit. (GitHub #66336) example:

    / {
        pit0: pit@40037000 {
            /* Other Pit DT Attributes */
            compatible = "nxp,pit";
            status = "disabled";
            num-channels = <1>;
            #address-cells = <1>;
            #size-cells = <0>;
    
            pit0_channel0: pit0_channel@0 {
                compatible = "nxp,pit-channel";
                reg = <0>;
                status = "disabled";
            };
    };
    
  • The nxp,kinetis-ethernet has been deprecated in favor of nxp,enet. All in tree SOCs were converted to use this new schema. Thus, all boards using NXP’s ENET peripheral will need to align to this binding in DT, which also comes with a different version driver. Alternatively, the Ethernet node can be deleted and redefined as the old binding to use the deprecated legacy driver. The primary advantage of the new binding is to be able to abstract an arbitrary phy through the mdio API. (GitHub #70400) Example of a basic board level ENET DT definition:

    &enet_mac {
        status = "okay";
        pinctrl-0 = <&pinmux_enet>;
        pinctrl-names = "default";
        phy-handle = <&phy>;
        zephyr,random-mac-address;
        phy-connection-type = "rmii";
    };
    
    &enet_mdio {
        status = "okay";
        pinctrl-0 = <&pinmux_enet_mdio>;
        pinctrl-names = "default";
        phy: phy@3 {
            compatible = "ethernet-phy";
            reg = <3>;
            status = "okay";
        };
    };
    
  • The nxp,kinetis-lptmr compatible string has been changed to nxp,lptmr. The old string will be usable for a short time, but should be replaced for it will be removed in the future.

  • Some of the driver API structs have been rename to have the required _driver_api suffix. (GitHub #72182) The following types have been renamed:

    • emul_sensor_backend_api to emul_sensor_driver_api

    • emul_bbram_backend_api to emul_bbram_driver_api

    • usbc_ppc_drv to usbc_ppc_driver_api

  • The driver for maxim,max31790 got split up into a MFD and an actual PWM driver. (GitHub #68433) Previously, an instance of this device could have been defined like this:

    max31790_max31790: max31790@20 {
        compatible = "maxim,max31790";
        status = "okay";
        reg = <0x20>;
        pwm-controller;
        #pwm-cells = <2>;
    };
    

    This can be converted to:

    max31790_max31790: max31790@20 {
        compatible = "maxim,max31790";
        status = "okay";
        reg = <0x20>;
    
        max31790_max31790_pwm: max31790_max31790_pwm {
            compatible = "maxim,max31790-pwm";
            status = "okay";
            pwm-controller;
            #pwm-cells = <2>;
        };
    };
    
  • The driver for invensense,icm42688 now correctly supports device tree configuration(GitHub #74267). Prior devicetrees may have tried to use the bindings to set sample rate and scale for the accel/gyro without any effect. The devicetree usage should now use the provided defines and include file along with new bindings which take these values.

    For example:

    #include <zephyr/dt-bindings/sensor/icm42688.h>
    
    icm42688: icm42688@0 {
        accel-pwr-mode = <ICM42688_ACCEL_LN>;
        accel-fs = <ICM42688_ACCEL_FS_16G>;
        accel-odr = <ICM42688_ACCEL_ODR_2000>;
        gyro-pwr-mode= <ICM42688_GYRO_LN>;
        gyro-fs = <ICM42688_GYRO_FS_2000>;
        gyro-odr = <ICM42688_GYRO_ODR_2000>;
    };
    
  • st,lis2mdl property spi-full-duplex changed to duplex = SPI_FULL_DUPLEX. Full duplex is now the default.

  • The DT property nxp,reference-supply of nxp,lpc-lpadc driver has been removed, users should remove this property from their devicetree if it is present. Added new phandle-array type DT property nxp,references, the user can use this property to specify the reference voltage and reference voltage value to be used by the lpadc. (GitHub #75005)

  • The DT properties mc,interface-type, mc,reset-gpio, and mc,interrupt-gpio of the microchip,ksz8081 phy binding have changed to microchip,interface-type, reset-gpios, and int-gpios, respectively (GitHub #73725)

Charger

  • Dropped constant-charge-current-max-microamp property in charger_max20335 driver because it did not reflect real chip functionality. (GitHub #69910)

  • Added enum key to constant-charge-voltage-max-microvolt property in maxim,max20335-charger binding to indicate invalid devicetree values at build time. (GitHub #69910)

Controller Area Network (CAN)

  • Removed the following deprecated CAN controller devicetree properties. Out-of-tree boards using these properties can switch to using the bitrate, sample-point, bitrate-data, and sample-point-data devicetree properties (or rely on CONFIG_CAN_DEFAULT_BITRATE and CONFIG_CAN_DEFAULT_BITRATE_DATA) for specifying the initial CAN bitrate:

    • sjw

    • prop-seg

    • phase-seg1

    • phase-seg2

    • sjw-data

    • prop-seg-data

    • phase-seg1-data

    • phase-seg2-data

    The bus-speed and bus-speed-data CAN controller devicetree properties have been deprecated.

    (GitHub #68714)

  • Support for manual bus-off recovery was reworked (GitHub #69460):

    • Automatic bus recovery will always be enabled upon driver initialization regardless of Kconfig options. Since CAN controllers are initialized in “stopped” state, no unwanted bus-off recovery will be started at this point.

    • The Kconfig CONFIG_CAN_AUTO_BUS_OFF_RECOVERY was renamed (and inverted) to CONFIG_CAN_MANUAL_RECOVERY_MODE, which is disabled by default. This Kconfig option enables support for the can_recover() API function and a new manual recovery mode (see the next bullet).

    • A new CAN controller operational mode CAN_MODE_MANUAL_RECOVERY was added. Support for this is only enabled if CONFIG_CAN_MANUAL_RECOVERY_MODE is enabled. Having this as a mode allows applications to inquire whether the CAN controller supports manual recovery mode via the can_get_capabilities() API function. The application can then either fail initialization or rely on automatic bus-off recovery. Having this as a mode furthermore allows CAN controller drivers not supporting manual recovery mode to fail early in can_set_mode() during application startup instead of failing when can_recover() is called at a later point in time.

Crypto

  • The CSS driver has been deprecated on NXP lpc55s36 (GitHub #71173).

Display

  • GC9X01 based displays now use the MIPI DBI driver class. These displays must now be declared within a MIPI DBI driver wrapper device, which will manage interfacing with the display. (GitHub #73686) For an example, see below:

    /* Legacy GC9X01 display definition */
    &spi0 {
        gc9a01: gc9a01@0 {
            status = "okay";
            compatible = "galaxycore,gc9x01x";
            reg = <0>;
            spi-max-frequency = <100000000>;
            cmd-data-gpios = <&gpio0 8 GPIO_ACTIVE_HIGH>;
            reset-gpios = <&gpio0 14 GPIO_ACTIVE_LOW>;
            ...
        };
    };
    
    /* New display definition with MIPI DBI device */
    
    #include <zephyr/dt-bindings/mipi_dbi/mipi_dbi.h>
    
    ...
    
    mipi_dbi {
        compatible = "zephyr,mipi-dbi-spi";
        dc-gpios = <&gpio0 8 GPIO_ACTIVE_HIGH>;
        reset-gpios = <&gpio0 14 GPIO_ACTIVE_LOW>;
        spi-dev = <&spi0>;
        #address-cells = <1>;
        #size-cells = <0>;
    
        gc9a01: gc9a01@0 {
            status = "okay";
            compatible = "galaxycore,gc9x01x";
            reg = <0>;
            mipi-max-frequency = <100000000>;
            ...
        };
    };
    
  • ST7735R based displays now use the MIPI DBI driver class. These displays must now be declared within a MIPI DBI driver wrapper device, which will manage interfacing with the display. Note that the cmd-data-gpios pin has changed polarity with this update, to align better with the new dc-gpios name. For an example, see below:

    /* Legacy ST7735R display definition */
    &spi0 {
        st7735r: st7735r@0 {
            compatible = "sitronix,st7735r";
            reg = <0>;
            spi-max-frequency = <32000000>;
            reset-gpios = <&gpio0 6 GPIO_ACTIVE_LOW>;
            cmd-data-gpios = <&gpio0 12 GPIO_ACTIVE_LOW>;
            ...
        };
    };
    
    /* New display definition with MIPI DBI device */
    
    #include <zephyr/dt-bindings/mipi_dbi/mipi_dbi.h>
    
    ...
    
    mipi_dbi {
        compatible = "zephyr,mipi-dbi-spi";
        reset-gpios = <&gpio0 6 GPIO_ACTIVE_LOW>;
        dc-gpios = <&gpio0 12 GPIO_ACTIVE_HIGH>;
        spi-dev = <&spi0>;
        #address-cells = <1>;
        #size-cells = <0>;
    
        st7735r: st7735r@0 {
            compatible = "sitronix,st7735r";
            reg = <0>;
            mipi-max-frequency = <32000000>;
            mipi-mode = <MIPI_DBI_MODE_SPI_4WIRE>;
            ...
        };
    };
    
  • UC81XX based displays now use the MIPI DBI driver class. These displays must now be declared within a MIPI DBI driver wrapper device, which will manage interfacing with the display. (GitHub #73812) Note that the dc-gpios pin has changed polarity with this update, for an example, see below:

    /* Legacy UC81XX display definition */
    &spi0 {
        uc8179: uc8179@0 {
            compatible = "ultrachip,uc8179";
            reg = <0>;
            spi-max-frequency = <4000000>;
            reset-gpios = <&gpio0 6 GPIO_ACTIVE_LOW>;
            dc-gpios = <&gpio0 12 GPIO_ACTIVE_LOW>;
            ...
        };
    };
    
    /* New display definition with MIPI DBI device */
    
    #include <zephyr/dt-bindings/mipi_dbi/mipi_dbi.h>
    
    ...
    
    mipi_dbi {
        compatible = "zephyr,mipi-dbi-spi";
        reset-gpios = <&gpio0 6 GPIO_ACTIVE_LOW>;
        dc-gpios = <&gpio0 12 GPIO_ACTIVE_HIGH>;
        spi-dev = <&spi0>;
        #address-cells = <1>;
        #size-cells = <0>;
        uc8179: uc8179@0 {
            compatible = "ultrachip,uc8179";
            reg = <0>;
            mipi-max-frequency = <4000000>;
            ...
        };
    };
    
  • ST7789V based displays now use the MIPI DBI driver class. These displays must now be declared within a MIPI DBI driver wrapper device, which will manage interfacing with the display. (GitHub #73750) Note that the cmd-data-gpios pin has changed polarity with this update, to align better with the new dc-gpios name. For an example, see below:

    /* Legacy ST7789V display definition */
    &spi0 {
        st7789: st7789@0 {
            compatible = "sitronix,st7789v";
            reg = <0>;
            spi-max-frequency = <32000000>;
            reset-gpios = <&gpio0 6 GPIO_ACTIVE_LOW>;
            cmd-data-gpios = <&gpio0 12 GPIO_ACTIVE_LOW>;
            ...
        };
    };
    
    /* New display definition with MIPI DBI device */
    
    #include <zephyr/dt-bindings/mipi_dbi/mipi_dbi.h>
    
    ...
    
    mipi_dbi {
        compatible = "zephyr,mipi-dbi-spi";
        reset-gpios = <&gpio0 6 GPIO_ACTIVE_LOW>;
        dc-gpios = <&gpio0 12 GPIO_ACTIVE_HIGH>;
        spi-dev = <&spi0>;
        #address-cells = <1>;
        #size-cells = <0>;
    
        st7789: st7789@0 {
            compatible = "sitronix,st7789v";
            reg = <0>;
            mipi-max-frequency = <32000000>;
            mipi-mode = <MIPI_DBI_MODE_SPI_4WIRE>;
            ...
        };
    };
    
  • SSD16XX based displays now use the MIPI DBI driver class (GitHub #73946). These displays must now be declared within a MIPI DBI driver wrapper device, which will manage interfacing with the display. Note that the dc-gpios pin has changed polarity with this update. For an example, see below:

    /* Legacy SSD16XX display definition */
    &spi0 {
        ssd1680: ssd1680@0 {
            compatible = "solomon,ssd1680";
            reg = <0>;
            spi-max-frequency = <4000000>;
            reset-gpios = <&gpio0 6 GPIO_ACTIVE_LOW>;
            dc-gpios = <&gpio0 12 GPIO_ACTIVE_LOW>;
            ...
        };
    };
    
    /* New display definition with MIPI DBI device */
    
    #include <zephyr/dt-bindings/mipi_dbi/mipi_dbi.h>
    
    ...
    
    mipi_dbi {
        compatible = "zephyr,mipi-dbi-spi";
        reset-gpios = <&gpio0 6 GPIO_ACTIVE_LOW>;
        dc-gpios = <&gpio0 12 GPIO_ACTIVE_HIGH>;
        spi-dev = <&spi0>;
        #address-cells = <1>;
        #size-cells = <0>;
    
        ssd1680: ssd1680@0 {
            compatible = "solomon,ssd1680";
            reg = <0>;
            mipi-max-frequency = <4000000>;
            ...
        };
    };
    
  • The orientation-flipped property has been removed from the SSD16XX display driver, as the driver now supports display rotation. Users should drop this property from their devicetree, and set orientation at runtime via display_set_orientation() (GitHub #73360)

Enhanced Serial Peripheral Interface (eSPI)

  • The macros ESPI_SLAVE_TO_MASTER and ESPI_MASTER_TO_SLAVE were renamed to ESPI_TARGET_TO_CONTROLLER and ESPI_CONTROLLER_TO_TARGET respectively to reflect the new terminology in eSPI 1.5 specification. The enum values ESPI_VWIRE_SIGNAL_SLV_BOOT_STS, ESPI_VWIRE_SIGNAL_SLV_BOOT_DONE and all ESPI_VWIRE_SIGNAL_SLV_GPIO_<NUMBER> signals were renamed to ESPI_VWIRE_SIGNAL_TARGET_BOOT_STS, ESPI_VWIRE_SIGNAL_TARGET_BOOT_DONE and ESPI_VWIRE_SIGNAL_TARGET_GPIO_<NUMBER> respectively to reflect the new terminology in eSPI 1.5 specification. (GitHub #68492) The Kconfig CONFIG_ESPI_SLAVE was renamed to CONFIG_ESPI_TARGET, similarly CONFIG_ESPI_SAF was renamed as CONFIG_ESPI_TAF (GitHub #73887)

GNSS

  • Basic power management support has been added to the gnss-nmea-generic driver. If CONFIG_PM_DEVICE=y the driver is now initialized in suspended mode and the application needs to call pm_device_action_run() with PM_DEVICE_ACTION_RESUME to start up the driver. (GitHub #71774)

Input

  • The analog-axis deadzone calibration value has been changed to be relative to the raw ADC values, similarly to min and max. The data structures and properties have been renamed to reflect that (from out-deadzone to in-deadzone) and when migrating to the new definition the value should be scaled accordingly. (GitHub #70377)

  • The holtek,ht16k33-keyscan driver has been converted to use the Input subsystem, callbacks have to be migrated to use the input APIs, zephyr,kscan-input can be used for backward compatibility. (GitHub #69875)

Interrupt Controller

  • The static auto-generation of the multilevel interrupt controller lookup table has been deprecated, and will be compiled only when the new compatibility Kconfig: CONFIG_LEGACY_MULTI_LEVEL_TABLE_GENERATION is enabled, which will eventually be removed in the coming releases.

    Multi-level interrupt controller drivers should be updated to use the newly created IRQ_PARENT_ENTRY_DEFINE macro to register itself with the new multi-level interrupt architecture. To make the macro easier to use, INTC_INST_ISR_TBL_OFFSET macro is made to deduce the software ISR table offset for a given driver instance, for pseudo interrupt controller child, use the INTC_CHILD_ISR_TBL_OFFSET macro instead. New devicetree macros (DT_INTC_GET_AGGREGATOR_LEVEL & DT_INST_INTC_GET_AGGREGATOR_LEVEL) have been added for an interrupt controller driver instance to pass its aggregator level into the IRQ_PARENT_ENTRY_DEFINE macro.

LED Strip

  • The property in-gpios defined in worldsemi,ws2812-gpio has been renamed to gpios. (GitHub #68514)

  • The chain-length and color-mapping properties have been added to all LED strip bindings and are now mandatory.

  • Added a new mandatory length function which returns the length (number of pixels) of an LED strip device.

  • Made update_channels function optional and removed unimplemented functions.

  • The CONFIG_WS2812_STRIP_DRIVER kconfig option has been removed. Previously, when using CONFIG_WS2812_STRIP_SPI, CONFIG_WS2812_STRIP_I2S, CONFIG_WS2812_STRIP_GPIO, or CONFIG_WS2812_STRIP_RPI_PICO_PIO, one of them had to be selected with CONFIG_WS2812_STRIP_DRIVER, but this is no longer necessary. Please set each option directly.

MDIO

Sensors

  • The chip devicetree property from the sensirion,shtcx sensor driver has been removed. Chip variants are now selected using the matching compatible property (GitHub #74033). For an example of the new shtc3 configuration, see below:

    &i2c0 {
        status = "okay";
    
        shtc3: shtc3@70 {
            compatible = "sensirion,shtc3", "sensirion,shtcx";
            reg = <0x70>;
            measure-mode = "normal";
            clock-stretching;
        };
    };
    

Serial

  • The Raspberry Pi UART driver uart_rpi_pico has been removed. Use uart_pl011 (arm,pl011) instead. (GitHub #71074)

Regulator

  • The nxp,vref driver no longer supports the ground selection function, as this setting should not be modified by the user. The DT property nxp,ground-select has been removed, users should remove this property from their devicetree if it is present. (GitHub #70642)

W1

  • The zephyr,w1-gpio 1-Wire master driver no longer defaults to enabling the internal pull-up resistor of the GPIO pin. The configuration is now taken from the pin’s configuration flags specified in devicetree. (GitHub #71789)

Watchdog

  • The nuvoton,npcx-watchdog driver has been changed to extend the max timeout period. The time of one watchdog count varies with the different pre-scalar settings. Removed CONFIG_WDT_NPCX_DELAY_CYCLES because it is no longer suitable to set the leading warning time. Instead, added the CONFIG_WDT_NPCX_WARNING_LEADING_TIME_MS to set the leading warning time in milliseconds.

Bluetooth

Bluetooth HCI

  • A new HCI driver API was introduced (GitHub #72323) and the old one deprecated. The new API follows the normal Zephyr driver model, with devicetree nodes, etc. The host now selects which driver instance to use as the controller by looking for a zephyr,bt-hci chosen property. The devicetree bindings for all HCI drivers derive from a common bt-hci.yaml base binding.

  • As part of the new HCI driver API, the zephyr,bt-uart chosen property is no longer used, rather the UART HCI drivers select their UART by looking for the parent devicetree node of the HCI driver instance node.

  • As part of the new HCI driver API, the zephyr,bt-hci-ipc chosen property is only used for the controller side, whereas the HCI driver now relies on nodes with the compatible string zephyr,bt-hci-ipc.

  • The BT_NO_DRIVER Kconfig option was removed. HCI drivers are no-longer behind a Kconfig choice, rather they can now be enabled and disabled independently, mostly based on their respective devicetree node being enabled or not.

  • The BT_HCI_VS_EXT Kconfig option was deleted and the feature is now included in the CONFIG_BT_HCI_VS Kconfig option.

  • The BT_HCI_VS_EVT Kconfig option was removed, since vendor event support is implicit if the CONFIG_BT_HCI_VS option is enabled.

  • The bt_read_static_addr() API was removed. This wasn’t really a completely public API, but since it was exposed by the public hci_driver.h header file the removal is mentioned here. Enable the CONFIG_BT_HCI_VS Kconfig option instead, and use vendor specific HCI commands API to get the Controller’s Bluetooth static address when available.

Bluetooth Mesh

  • The model metadata pointer declaration of bt_mesh_model has been changed to add const qualifiers. The data pointer of bt_mesh_models_metadata_entry got const qualifier too. The model’s metadata structure and metadata raw value can be declared as permanent constants in the non-volatile memory. (GitHub #69679)

  • The model metadata pointer declaration of bt_mesh_model has been changed to a single const * and redundant metadata pointer from bt_mesh_health_srv is removed. Consequently, BT_MESH_MODEL_HEALTH_SRV definition is changed to use variable argument notation. Now, when your implementation supports CONFIG_BT_MESH_LARGE_COMP_DATA_SRV and when you need to specify metadata for Health Server model, simply pass metadata as the last argument to the BT_MESH_MODEL_HEALTH_SRV macro, otherwise omit the last argument. (GitHub #71281)

Bluetooth Audio

Bluetooth Classic

  • The source files of Host BR/EDR have been moved to subsys/bluetooth/host/classic. The Header files of Host BR/EDR have been moved to include/zephyr/bluetooth/classic. Removed the CONFIG_BT_BREDR. It is replaced by new option CONFIG_BT_CLASSIC. (GitHub #69651)

Bluetooth Host

  • The advertiser options BT_LE_ADV_OPT_USE_NAME and BT_LE_ADV_OPT_FORCE_NAME_IN_AD are deprecated in this release. The application need to include the device name explicitly. One way to do it is by adding the following to the advertising data or scan response data passed to the host:

    BT_DATA(BT_DATA_NAME_COMPLETE, CONFIG_BT_DEVICE_NAME, sizeof(CONFIG_BT_DEVICE_NAME) - 1)
    

    (GitHub #71686)

  • The field init_credits in bt_l2cap_le_endpoint has been removed as it was no longer used in Zephyr 3.4.0 and later. Any references to this field should be removed. No further action is needed.

  • BT_LE_ADV_PARAM now returns a const pointer. Any place where the result is stored in a local variable such as struct bt_le_adv_param *param = BT_LE_ADV_CONN; will need to be updated to const struct bt_le_adv_param *param = BT_LE_ADV_CONN; or use it for initialization like struct bt_le_adv_param param = *BT_LE_ADV_CONN;

    The change to BT_LE_ADV_PARAM also affects all of its derivatives, including but not limited to:

    (GitHub #75065)

  • CONFIG_BT_BUF_ACL_RX_COUNT now needs to be larger than CONFIG_BT_MAX_CONN. This was always the case due to the design of the HCI interface. It is now being enforced through a build-time assertion.

    (GitHub #75592)

Bluetooth Crypto

Networking

  • Deprecate the CONFIG_NET_SOCKETS_POSIX_NAMES option. It is a legacy option and was used to allow user to call BSD socket API while not enabling POSIX API. This could cause complications when building applications that wanted to enable the CONFIG_POSIX_API option. This means that if the application wants to use normal BSD socket interface, then it needs to enable CONFIG_POSIX_API. If the application does not want or is not able to enable that option, then the socket API calls need to be prefixed by a zsock_ string. All the sample applications that use BSD socket interface are changed to enable CONFIG_POSIX_API. Internally the network stack will not enable POSIX API option which means that various network libraries that use sockets, are converted to use the zsock_* API calls. (GitHub #69950)

  • The zperf zperf_results struct is changed to support 64 bits transferred bytes (total_len) and test duration (time_in_us and client_time_in_us), instead of 32 bits. This will make the long-duration zperf test show with correct throughput result. (GitHub #69500)

  • Each IPv4 address assigned to a network interface has an IPv4 netmask tied to it instead of being set for the whole interface. If there is only one IPv4 address specified for a network interface, nothing changes from the user point of view. But, if there is more than one IPv4 address / network interface, the netmask must be specified for each IPv4 address separately. (GitHub #68419)

  • Virtual network interface API no longer has the input callback. The input callback was used to read the inner IPv4/IPv6 packets in an IP tunnel. This incoming tunnel read is now implemented in the recv callback. (GitHub #70549)

  • Virtual LAN (VLAN) implementation is changed to use the Virtual network interfaces. There are no API changes, but the type of a VLAN network interface is changed from ETHERNET to VIRTUAL. This could require changes to the code that sets the VLAN tags to a network interface. For example in the net_eth_is_vlan_enabled() API, the 2nd interface parameter must point to the main Ethernet interface, and not to the VLAN interface. (GitHub #70345)

  • Modified the wifi connect command to use key-value format for the arguments. In the previous implementation, we were identifying an option using its position in the argument string. This made it difficult to deal with optional arguments or extending the support for other options. Having this key-value format makes it easier to extend the options that can be passed to the connect command. wifi -h will give more information about the usage of connect command. (GitHub #70024)

  • The Kconfig CONFIG_NET_TCP_ACK_TIMEOUT has been deprecated. Its usage was limited to TCP handshake only, and in such case the total timeout should depend on the total retransmission timeout (as in other cases) making the config redundant and confusing. Use CONFIG_NET_TCP_INIT_RETRANSMISSION_TIMEOUT and CONFIG_NET_TCP_RETRY_COUNT instead to control the total timeout at the TCP level. (GitHub #70731)

  • In LwM2M API, the callback type lwm2m_engine_set_data_cb_t has now an additional parameter offset. This parameter is used to indicate the offset of the data during a Coap Block-wise transfer. Any post write, validate or some firmware callbacks should be updated to include this parameter. (GitHub #72590)

  • The DNS resolver and mDNS/LLMNR responders are converted to use socket service API. This means that the number of pollable sockets in the system might need to be increased. Please check that the values of CONFIG_NET_SOCKETS_POLL_MAX and CONFIG_POSIX_MAX_FDS are high enough. Unfortunately no exact values for these can be given as it depends on application needs and usage. (GitHub #72834)

  • The packet socket (type AF_PACKET) protocol field in socket API call has changed. The protocol field should be in network byte order so that we are compatible with Linux socket calls. Linux expects the protocol field to be htons(ETH_P_ALL) if it is desired to receive all the network packets. See details in https://www.man7.org/linux/man-pages/man7/packet.7.html documentation. (GitHub #73338)

  • TCP now uses SHA-256 instead of MD5 for ISN generation. The crypto support for this hash computation was also changed from Mbed TLS to PSA APIs. This was achieved by making CONFIG_NET_TCP_ISN_RFC6528 depend on PSA_WANT_ALG_SHA_256 instead of legacy CONFIG_MBEDTLS_* features. (GitHub #71827)

Other Subsystems

Flash map

  • The crypto backend for the flash check functions (CONFIG_FLASH_AREA_CHECK_INTEGRITY_BACKEND), previously provided through either TinyCrypt or Mbed TLS, is now provided through either PSA or Mbed TLS. The updated Mbed TLS implementation has a slightly smaller footprint than the previous TinyCrypt one, and the PSA implementation offers an even greater footprint reduction for devices built with TF-M. PSA is the supported way forward, however as of now you may still use Mbed TLS if you cannot afford the one-time cost of enabling the PSA API (CONFIG_MBEDTLS_PSA_CRYPTO_C for devices without TF-M). GitHub #73511

hawkBit

MCUmgr

  • The support for SHA-256 (when using checksum/hash functions), previously provided by either TinyCrypt or Mbed TLS, is now provided by either PSA or Mbed TLS. PSA is the recommended API going forward, however, if it is not already enabled (CONFIG_MBEDTLS_PSA_CRYPTO_CLIENT) and you have tight code size constraints, you may be able to save 1.3 KB by using Mbed TLS instead.

Modem

POSIX API

  • The POSIX API Kconfig deprecations may require changes to Kconfig files (prj.conf, etc), as outlined in the release notes. A more automated approach is available via the provided migration script. Simply run the following:

    $ python ${ZEPHYR_BASE}/scripts/utils/migrate_posix_kconfigs.py -r root_path
    

State Machine Framework

  • The SMF_CREATE_STATE macro now always takes 5 arguments. The amount of arguments is now independent of the values of CONFIG_SMF_ANCESTOR_SUPPORT and CONFIG_SMF_INITIAL_TRANSITION. If the additional arguments are not used, they have to be set to NULL. (GitHub #71250)

  • SMF now follows a more UML-like transition flow when the transition source is a parent of the state called by smf_run_state(). Exit actions up to (but not including) the Least Common Ancestor of the transition source and target state will be executed, as will entry actions from (but not including) the LCA down to the target state. (GitHub #71675)

  • Previously, calling smf_set_state() with a new_state set to NULL would execute all exit actions from the current state to the topmost parent, with the expectation the topmost exit action would terminate the state machine. Passing NULL is now not allowed. Instead create a ‘terminate’ state at the top level, and call smf_set_terminate() from its entry action.

UpdateHub

Architectures