lib: nrf_modem: init once on dfu apply

applications/asset_tracker_v2/src/main.c

@@ -174,41 +174,48 @@ static void sub_state_set(enum sub_state_type new_state)
 }
 
 #if defined(CONFIG_NRF_MODEM_LIB)
-/* Check the return code from nRF modem library initialization to ensure that
- * the modem is rebooted if a modem firmware update is ready to be applied or
- * an error condition occurred during firmware update or library initialization.
- */
-static void modem_init(void)
-{
-	int ret = nrf_modem_lib_init();
 
-	/* Handle return values relating to modem firmware update */
-	switch (ret) {
-	case 0:
-		/* Initialization successful, no action required. */
-		return;
+static void on_modem_lib_dfu(int dfu_res, void *ctx)
+{
+	switch (dfu_res) {
 	case NRF_MODEM_DFU_RESULT_OK:
-		LOG_DBG("MODEM UPDATE OK. Will run new modem firmware after reboot");
-		break;
+		LOG_DBG("nRF Modem firmware update succeeded");
+		/* Fallthrough */
 	case NRF_MODEM_DFU_RESULT_UUID_ERROR:
 	case NRF_MODEM_DFU_RESULT_AUTH_ERROR:
-		LOG_ERR("MODEM UPDATE ERROR %d. Will run old firmware", ret);
+		LOG_ERR("MODEM UPDATE ERROR 0x%x. Running old firmware", dfu_res);
 		break;
 	case NRF_MODEM_DFU_RESULT_HARDWARE_ERROR:
 	case NRF_MODEM_DFU_RESULT_INTERNAL_ERROR:
-		LOG_ERR("MODEM UPDATE FATAL ERROR %d. Modem failure", ret);
+		LOG_ERR("MODEM UPDATE FATAL ERROR 0x%x. Modem failure", dfu_res);
 		break;
 	case NRF_MODEM_DFU_RESULT_VOLTAGE_LOW:
-		LOG_ERR("MODEM UPDATE CANCELLED %d.", ret);
+		LOG_ERR("MODEM UPDATE CANCELLED 0x%x.", dfu_res);
 		LOG_ERR("Please reboot once you have sufficient power for the DFU");
 		break;
 	default:
-		/* All non-zero return codes other than DFU result codes are
-		 * considered irrecoverable and a reboot is needed.
-		 */
-		LOG_ERR("nRF modem lib initialization failed, error: %d", ret);
+		/* Unknown DFU result code */
+		LOG_ERR("nRF modem DFU failed, error: 0x%x", dfu_res);
 		break;
 	}
+}
+
+NRF_MODEM_LIB_ON_DFU_RES(main_dfu_hook, on_modem_lib_dfu, NULL);
+
+/* Check the return code from nRF modem library initialization to ensure that
+ * the modem is rebooted or an error condition occurred during library initialization.
+ */
+static void modem_init(void)
+{
+	int ret;
+
+	ret = nrf_modem_lib_init();
+	if (ret == 0) {
+		LOG_DBG("nRF Modem Library initialized successfully");
+		return;
+	}
+
+	LOG_ERR("nRF modem lib initialization failed, error: %d", ret);
 
 #if defined(CONFIG_NRF_CLOUD_FOTA)
 	/* Ignore return value, rebooting below */

applications/serial_lte_modem/src/main.c

@@ -47,6 +47,8 @@ static void indicate_wk(struct k_work *work);
 
 BUILD_ASSERT(CONFIG_SLM_WAKEUP_PIN >= 0, "Wake up pin not configured");
 
+NRF_MODEM_LIB_ON_DFU_RES(main_dfu_hook, nrf_modem_on_dfu_res, NULL);
+
 #if defined(CONFIG_NRF_MODEM_LIB_ON_FAULT_APPLICATION_SPECIFIC)
 static void on_modem_failure_shutdown(struct k_work *item);
 static void on_modem_failure_reinit(struct k_work *item);
@@ -244,54 +246,40 @@ void enter_shutdown(void)
 	nrf_regulators_system_off(NRF_REGULATORS_NS);
 }
 
-bool handle_nrf_modem_lib_init_ret(int ret)
+static void nrf_modem_on_dfu_res(int dfu_res, void *ctx)
 {
-	switch (ret) {
-	case 0:
-		return false; /* Initialization successful, no action required. */
+	switch (dfu_res) {
 	case NRF_MODEM_DFU_RESULT_OK:
-		LOG_INF("MODEM UPDATE OK. Will run new firmware");
+		LOG_INF("nRF Modem firmware update succeeded");
 		fota_stage = FOTA_STAGE_COMPLETE;
 		fota_status = FOTA_STATUS_OK;
 		fota_info = 0;
 		break;
 	case NRF_MODEM_DFU_RESULT_UUID_ERROR:
 	case NRF_MODEM_DFU_RESULT_AUTH_ERROR:
-		LOG_ERR("MODEM UPDATE ERROR %d. Will run old firmware", ret);
+		LOG_ERR("MODEM UPDATE ERROR 0x%x. Running old firmware", dfu_res);
 		fota_status = FOTA_STATUS_ERROR;
-		fota_info = ret;
+		fota_info = dfu_res;
 		break;
 	case NRF_MODEM_DFU_RESULT_HARDWARE_ERROR:
 	case NRF_MODEM_DFU_RESULT_INTERNAL_ERROR:
-		LOG_ERR("MODEM UPDATE FATAL ERROR %d. Modem failure", ret);
+		LOG_ERR("MODEM UPDATE FATAL ERROR 0x%x", dfu_res);
+		LOG_ERR("Please program full modem firmware with the bootloader or external tools");
 		fota_status = FOTA_STATUS_ERROR;
-		fota_info = ret;
+		fota_info = dfu_res;
 		break;
 	case NRF_MODEM_DFU_RESULT_VOLTAGE_LOW:
-		LOG_ERR("MODEM UPDATE CANCELLED %d.", ret);
+		LOG_ERR("MODEM UPDATE CANCELLED 0x%x.", dfu_res);
 		LOG_ERR("Please reboot once you have sufficient power for the DFU");
 		fota_stage = FOTA_STAGE_ACTIVATE;
 		fota_status = FOTA_STATUS_ERROR;
-		fota_info = ret;
+		fota_info = dfu_res;
 		break;
 	default:
-		if (ret >= 0) {
-			LOG_WRN("Unhandled nrf_modem_lib_init() return code %d.", ret);
-			break;
-		}
-		/* All non-zero return codes other than DFU result codes are
-		 * considered irrecoverable and a reboot is needed.
-		 */
-		LOG_ERR("nRF modem lib initialization failed, error: %d", ret);
+		LOG_ERR("Unknown DFU result: 0x%x", dfu_res);
 		fota_status = FOTA_STATUS_ERROR;
-		fota_info = ret;
-		slm_settings_fota_save();
-		LOG_WRN("Rebooting...");
-		LOG_PANIC();
-		sys_reboot(SYS_REBOOT_COLD);
-		break;
+		fota_info = dfu_res;
 	}
-	return true;
 }
 
 static void handle_mcuboot_swap_ret(void)
@@ -379,20 +367,20 @@ int main(void)
 		LOG_WRN("Failed to init slm settings");
 	}
 
-	const int ret = nrf_modem_lib_init();
-
+	int ret = nrf_modem_lib_init();
 	if (ret < 0) {
 		LOG_ERR("Modem library init failed, err: %d", ret);
-		return ret;
+		if (ret != -EAGAIN) {
+			LOG_ERR("Please program full modem firmware with the bootloader or "
+				"external tools");
+		}
 	}
 
 	/* Post-FOTA handling */
 	if (fota_stage != FOTA_STAGE_INIT) {
-		if (fota_type == DFU_TARGET_IMAGE_TYPE_MODEM_DELTA) {
-			slm_finish_modem_fota(ret);
-		} else if (fota_type == DFU_TARGET_IMAGE_TYPE_MCUBOOT) {
+		if (fota_type == DFU_TARGET_IMAGE_TYPE_MCUBOOT) {
 			handle_mcuboot_swap_ret();
-		} else {
+		} else if (fota_type != DFU_TARGET_IMAGE_TYPE_MODEM_DELTA) {
 			LOG_ERR("Unknown DFU type: %d", fota_type);
 			fota_status = FOTA_STATUS_ERROR;
 			fota_info = -EAGAIN;

applications/serial_lte_modem/src/slm_at_commands.c

@@ -250,17 +250,18 @@ static int handle_at_modemreset(enum at_cmd_type type)
 		++step;
 
 		ret = nrf_modem_lib_init();
+
+		/* nrf_modem_dfu_res() is called in nrf_modem_lib_init with the DFU result.  */
+		if ((fota_stage != FOTA_STAGE_INIT &&
+		     fota_type == DFU_TARGET_IMAGE_TYPE_MODEM_DELTA)) {
+			slm_fota_post_process();
+		}
+
 		if (ret < 0) {
 			break;
 		}
 		++step;
 
-		if (ret > 0 || (fota_stage != FOTA_STAGE_INIT
-					&& fota_type == DFU_TARGET_IMAGE_TYPE_MODEM_DELTA)) {
-			slm_finish_modem_fota(ret);
-			slm_fota_post_process();
-		}
-
 		/* Success. */
 		rsp_send("\r\n#XMODEMRESET: 0\r\n");
 		return 0;

applications/serial_lte_modem/src/slm_at_fota.c

@@ -372,30 +372,3 @@ void slm_fota_post_process(void)
 		slm_settings_fota_save();
 	}
 }
-
-void slm_finish_modem_fota(int modem_lib_init_ret)
-{
-	if (handle_nrf_modem_lib_init_ret(modem_lib_init_ret)) {
-		char buf[40];
-
-		LOG_INF("Re-initializing the modem due to"
-				" ongoing modem firmware update.");
-
-		/* The second init needs to be done regardless of the return value.
-		 * Refer to the below link for more information on the procedure.
-		 * https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrfxlib/nrf_modem/doc/delta_dfu.html#reinitializing-the-modem-to-run-the-new-firmware
-		 */
-		modem_lib_init_ret = nrf_modem_lib_init();
-		handle_nrf_modem_lib_init_ret(modem_lib_init_ret);
-
-		nrf_modem_at_cmd(buf, sizeof(buf), "%s", "AT%SHORTSWVER");
-		if (strstr(buf, "1.3.4") || strstr(buf, "1.3.5")) {
-			/* Those versions suffer from a bug that provokes UICC failure (+CEREG: 90)
-			 * after the update, preventing the modem from registering to the network.
-			 */
-			LOG_INF("Applying the workaround to a modem firmware update issue...");
-			nrf_modem_lib_shutdown();
-			nrf_modem_lib_init();
-		}
-	}
-}

applications/serial_lte_modem/src/slm_at_fota.h

@@ -57,21 +57,5 @@ int slm_at_fota_uninit(void);
  */
 void slm_fota_post_process(void);
 
-/**
- * @brief Finishes the modem firmware update.
- *
- * This is to be called after the application or modem
- * has been rebooted and a modem firmware update is ongoing.
- */
-void slm_finish_modem_fota(int modem_lib_init_ret);
-
-/**
- * @brief Handles @ref nrf_modem_lib_init() return values
- * relating to modem firmware update.
- *
- * @return Whether the modem must be re-initialized.
- */
-bool handle_nrf_modem_lib_init_ret(int modem_lib_init_ret);
-
 /** @} */
 #endif /* SLM_AT_FOTA_ */

include/modem/nrf_modem_lib.h

@@ -38,8 +38,20 @@ extern "C" {
  * Use @ref nrf_modem_lib_init() to initialize in normal mode and
  * @ref nrf_modem_lib_bootloader_init() to initialize the Modem library in bootloader mode.
  *
- * @return int Zero on success, a positive value @em nrf_modem_dfu when executing
- *         Modem firmware updates, and negative errno on other failures.
+ * @retval Zero on success.
+ *
+ * @retval -NRF_EPERM The Modem library is already initialized.
+ * @retval -NRF_EFAULT @c init_params is @c NULL.
+ * @retval -NRF_ENOLCK Not enough semaphores.
+ * @retval -NRF_ENOMEM Not enough shared memory.
+ * @retval -NRF_EINVAL Control region size is incorrect or missing handlers in @c init_params.
+ * @retval -NRF_ENOTSUPP RPC version mismatch.
+ * @retval -NRF_ETIMEDOUT Operation timed out.
+ * @retval -NRF_ACCESS Modem firmware authentication failure.
+ * @retval -NRF_EAGAIN Modem device firmware upgrade failure.
+ *		       DFU is scheduled at next initialization.
+ * @retval -NRF_EIO Modem device firmware upgrade failure.
+ *		    Reprogramming the modem firmware is necessary to recover.
  */
 int nrf_modem_lib_init(void);
 
@@ -54,7 +66,17 @@ int nrf_modem_lib_init(void);
  * Use @ref nrf_modem_lib_init() to initialize in normal mode and
  * @ref nrf_modem_lib_bootloader_init() to initialize the Modem library in bootloader mode.
  *
- * @return int Zero on success, non-zero otherwise.
+ * @retval Zero on success.
+ *
+ * @retval -NRF_EPERM The Modem library is already initialized.
+ * @retval -NRF_EFAULT @c init_params is @c NULL.
+ * @retval -NRF_ENOLCK Not enough semaphores.
+ * @retval -NRF_ENOMEM Not enough shared memory.
+ * @retval -NRF_EINVAL Missing handler in @c init_params.
+ * @retval -NRF_EACCES Bad root digest.
+ * @retval -NRF_ETIMEDOUT Operation timed out.
+ * @retval -NRF_EIO Bootloader fault.
+ * @retval -NRF_ENOSYS Operation not available.
  */
 int nrf_modem_lib_bootloader_init(void);
 
@@ -67,6 +89,20 @@ int nrf_modem_lib_bootloader_init(void);
  */
 int nrf_modem_lib_shutdown(void);
 
+/**
+ * @brief Modem library dfu callback struct.
+ */
+struct nrf_modem_lib_dfu_cb {
+	/**
+	 * @brief Callback function.
+	 * @param dfu_res The return value of nrf_modem_init()
+	 * @param ctx User-defined context
+	 */
+	void (*callback)(int dfu_res, void *ctx);
+	/** User defined context */
+	void *context;
+};
+
 /**
  * @brief Modem library initialization callback struct.
  */
@@ -94,6 +130,25 @@ struct nrf_modem_lib_shutdown_cb {
 	void *context;
 };
 
+/**
+ * @brief Define a callback for DFU result @ref nrf_modem_lib_init calls.
+ *
+ * The callback function @p _callback is invoked after the library has been initialized.
+ *
+ * @note The @c NRF_MODEM_LIB_ON_DFU_RES callback can be used to subscribe to the result of a modem
+ * DFU operation.
+ *
+ * @param name Callback name
+ * @param _callback Callback function name
+ * @param _context User-defined context for the callback
+ */
+#define NRF_MODEM_LIB_ON_DFU_RES(name, _callback, _context)                                        \
+	static void _callback(int dfu_res, void *ctx);                                             \
+	STRUCT_SECTION_ITERABLE(nrf_modem_lib_dfu_cb, nrf_modem_dfu_hook_##name) = {               \
+		.callback = _callback,                                                             \
+		.context = _context,                                                               \
+	};
+
 /**
  * @brief Define a callback for @ref nrf_modem_lib_init calls.
  *