lorawan: add devicetime request support

Add devicetime request support.
Update lorawan sample
Related to Issue #55072

Co-authored-by: Jan Kowalewski <jkowalewski@cthings.co>

Signed-off-by: romain pelletant <romain.pelletant@fullfreqs.com>
Signed-off-by: Jan Kowalewski <jkowalewski@cthings.co>

include/zephyr/lorawan/lorawan.h

@@ -108,6 +108,7 @@ enum lorawan_message_type {
  */
 enum lorawan_dl_flags {
 	LORAWAN_DATA_PENDING = BIT(0),
+	LORAWAN_TIME_UPDATED = BIT(1),
 };
 
 /**
@@ -378,6 +379,32 @@ void lorawan_get_payload_sizes(uint8_t *max_next_payload_size,
  */
 int lorawan_set_region(enum lorawan_region region);
 
+/**
+ * @brief Request for time according to DeviceTimeReq MAC cmd
+ *
+ * Append MAC DevTimeReq command. It will be processed on next send
+ * message or force sending empty message to request time immediately.
+ *
+ * @param force_request Immediately send an empty message to execute the request
+ * @return 0 if successful, negative errno otherwise
+ */
+int lorawan_request_device_time(bool force_request);
+
+/**
+ * @brief Retrieve the current time from LoRaWAN stack updated by
+ * DeviceTimeAns on MAC layer.
+ *
+ * This function uses the GPS epoch format, as used in all LoRaWAN services.
+ *
+ * The GPS epoch started on 1980-01-06T00:00:00Z, but has since diverged
+ * from UTC, as it does not consider corrections like leap seconds.
+ *
+ * @param gps_time Synchronized time in GPS epoch format truncated to 32-bit.
+ *
+ * @return 0 if successful, -EAGAIN if the clock is not yet synchronized.
+ */
+int lorawan_device_time_get(uint32_t *gps_time);
+
 #ifdef CONFIG_LORAWAN_APP_CLOCK_SYNC
 
 /**

samples/subsys/lorawan/class_a/src/main.c

@@ -27,12 +27,11 @@ LOG_MODULE_REGISTER(lorawan_class_a);
 
 char data[] = {'h', 'e', 'l', 'l', 'o', 'w', 'o', 'r', 'l', 'd'};
 
-static void dl_callback(uint8_t port, uint8_t flags,
+static void dl_callback(uint8_t port, uint8_t flags, int16_t rssi, int8_t snr, uint8_t len,
-			int16_t rssi, int8_t snr,
+			const uint8_t *hex_data)
-			uint8_t len, const uint8_t *hex_data)
 {
-	LOG_INF("Port %d, Pending %d, RSSI %ddB, SNR %ddBm",
+	LOG_INF("Port %d, Pending %d, RSSI %ddB, SNR %ddBm, Time %d", port,
-			port, flags & LORAWAN_DATA_PENDING, rssi, snr);
+		flags & LORAWAN_DATA_PENDING, rssi, snr, !!(flags & LORAWAN_TIME_UPDATED));
 	if (hex_data) {
 		LOG_HEXDUMP_INF(hex_data, len, "Payload: ");
 	}

samples/subsys/lorawan/fuota/src/main.c

@@ -24,11 +24,10 @@ LOG_MODULE_REGISTER(lorawan_fuota, CONFIG_LORAWAN_SERVICES_LOG_LEVEL);
 
 char data[] = {'h', 'e', 'l', 'l', 'o', 'w', 'o', 'r', 'l', 'd'};
 
-static void downlink_info(uint8_t port, bool data_pending, int16_t rssi, int8_t snr,
+static void downlink_info(uint8_t port, uint8_t flags, int16_t rssi, int8_t snr, uint8_t len,
-			  uint8_t len, const uint8_t *data)
+			  const uint8_t *data)
 {
-	LOG_INF("Received from port %d, pending %d, RSSI %ddB, SNR %ddBm",
+	LOG_INF("Received from port %d, flags %d, RSSI %ddB, SNR %ddBm", port, flags, rssi, snr);
-		port, data_pending, rssi, snr);
 	if (data) {
 		LOG_HEXDUMP_INF(data, len, "Payload: ");
 	}

subsys/lorawan/lorawan.c

@@ -68,6 +68,7 @@ K_MUTEX_DEFINE(lorawan_send_mutex);
 static enum lorawan_datarate default_datarate;
 static enum lorawan_datarate current_datarate;
 static bool lorawan_adr_enable;
+static bool lorawan_device_time_updated_once;
 
 static sys_slist_t dl_callbacks;
 
@@ -162,9 +163,14 @@ static void mcps_indication_handler(McpsIndication_t *mcps_indication)
 	if (lorawan_adr_enable) {
 		datarate_observe(false);
 	}
+	/* Save time has been updated at least once */
+	if (!lorawan_device_time_updated_once && mcps_indication->DeviceTimeAnsReceived) {
+		lorawan_device_time_updated_once = true;
+	}
 
 	/* IsUplinkTxPending also indicates pending downlinks */
 	flags |= (mcps_indication->IsUplinkTxPending == 1 ? LORAWAN_DATA_PENDING : 0);
+	flags |= (mcps_indication->DeviceTimeAnsReceived ? LORAWAN_TIME_UPDATED : 0);
 
 	/* Iterate over all registered downlink callbacks */
 	SYS_SLIST_FOR_EACH_CONTAINER(&dl_callbacks, cb, node) {
@@ -202,6 +208,9 @@ static void mlme_confirm_handler(MlmeConfirm_t *mlme_confirm)
 		/* Not implemented */
 		LOG_INF("Link check not implemented yet!");
 		break;
+	case MLME_DEVICE_TIME:
+		LOG_INF("DevTimeReq done");
+		break;
 	default:
 		break;
 	}
@@ -382,6 +391,42 @@ int lorawan_set_region(enum lorawan_region region)
 	return 0;
 }
 
+int lorawan_request_device_time(bool force_request)
+{
+	int ret = 0;
+	LoRaMacStatus_t status;
+	MlmeReq_t mlme_req;
+
+	mlme_req.Type = MLME_DEVICE_TIME;
+	status = LoRaMacMlmeRequest(&mlme_req);
+	if (status != LORAMAC_STATUS_OK) {
+		LOG_ERR("DeviceTime Req. failed: %s", lorawan_status2str(status));
+		ret = lorawan_status2errno(status);
+		return ret;
+	}
+
+	if (force_request) {
+		ret = lorawan_send(0U, "", 0U, LORAWAN_MSG_UNCONFIRMED);
+	}
+
+	return ret;
+}
+
+int lorawan_device_time_get(uint32_t *gps_time)
+{
+	SysTime_t local_time;
+
+	__ASSERT(gps_time != NULL, "gps_time parameter is required");
+
+	if (lorawan_device_time_updated_once) {
+		local_time = SysTimeGet();
+		*gps_time = local_time.Seconds - UNIX_GPS_EPOCH_OFFSET;
+		return 0;
+	} else {
+		return -EAGAIN;
+	}
+}
+
 int lorawan_join(const struct lorawan_join_config *join_cfg)
 {
 	MibRequestConfirm_t mib_req;