memfault: Various fixes for FOTA

 - Use nrf modem library CFUN callback to prevent modem info
   calls in offline and powered off states. This is needed instead of
   fetching the func mode due to the modem being shutdown when
   a lte handler notification is received.

 - Ease up on the logging when modem info API are called.
   Its expected that they fail in certain scenarios, and logging an
   error in those instances is not necessary.

Signed-off-by: Simen S. Røstad <[email protected]>

modules/memfault-firmware-sdk/memfault_lte_metrics.c

@@ -9,6 +9,7 @@
 
 #include <modem/lte_lc.h>
 #include <modem/lte_lc_trace.h>
+#include <modem/nrf_modem_lib.h>
 
 #if defined(CONFIG_MODEM_INFO)
 #include <modem/modem_info.h>
@@ -23,6 +24,16 @@
 LOG_MODULE_DECLARE(memfault_ncs_metrics, CONFIG_MEMFAULT_NCS_LOG_LEVEL);
 
 static bool connected;
+static enum lte_lc_func_mode current_func_mode;
+
+static void memfault_on_modem_cfun(int mode, void *ctx)
+{
+	ARG_UNUSED(ctx);
+
+	current_func_mode = mode;
+}
+
+NRF_MODEM_LIB_ON_CFUN(memfault_cfun_hook, memfault_on_modem_cfun, NULL);
 
 #if CONFIG_MEMFAULT_NCS_STACK_METRICS
 static struct memfault_ncs_metrics_thread lte_metrics_thread = {
@@ -64,45 +75,44 @@ static void modem_params_get(void)
 
 	err = modem_info_get_rsrp(&rsrp);
 	if (err) {
-		LOG_WRN("LTE RSRP value collection failed, error: %d", err);
-	} else {
-		err = MEMFAULT_METRIC_SET_SIGNED(ncs_lte_rsrp_dbm, rsrp);
-		if (err) {
-			LOG_ERR("Failed to set ncs_lte_rsrp_dbm");
-		}
-	};
+		return;
+	}
+
+	err = MEMFAULT_METRIC_SET_SIGNED(ncs_lte_rsrp_dbm, rsrp);
+	if (err) {
+		LOG_ERR("Failed to set ncs_lte_rsrp_dbm");
+		return;
+	}
 
 	err = modem_info_get_current_band(&band);
-	if (err != 0) {
-		LOG_WRN("Network band collection failed, error: %d", err);
-	} else {
-		err = MEMFAULT_METRIC_SET_UNSIGNED(ncs_lte_band, band);
-		if (err) {
-			LOG_ERR("Failed to set nce_lte_band");
-		}
+	if (err) {
+		return;
+	}
+
+	err = MEMFAULT_METRIC_SET_UNSIGNED(ncs_lte_band, band);
+	if (err) {
+		LOG_ERR("Failed to set nce_lte_band");
+		return;
 	}
 
 	err = modem_info_get_snr(&snr);
-	if (err != 0) {
-		LOG_WRN("SNR collection failed, error: %d", err);
-	} else {
-		err = MEMFAULT_METRIC_SET_SIGNED(ncs_lte_snr_decibels, snr);
-		if (err) {
-			LOG_ERR("Failed to set ncs_lte_snr_decibels");
-		}
+	if (err) {
+		return;
+	}
+
+	err = MEMFAULT_METRIC_SET_SIGNED(ncs_lte_snr_decibels, snr);
+	if (err) {
+		LOG_ERR("Failed to set ncs_lte_snr_decibels");
+		return;
 	}
 #endif
 }
 
 static void lte_handler(const struct lte_lc_evt *const evt)
 {
 	int err;
-	enum lte_lc_func_mode mode = LTE_LC_FUNC_MODE_OFFLINE;
 
-	err = lte_lc_func_mode_get(&mode);
-	if (err) {
-		LOG_ERR("Failed to get LTE mode, error: %d", err);
-	} else if (mode != LTE_LC_FUNC_MODE_OFFLINE) {
+	if (current_func_mode == LTE_LC_FUNC_MODE_NORMAL) {
 		modem_params_get();
 	}