lorawan: queriable minimum datarate

Add a function to query the minimum possible datarate on the network.
This value may change over the lifetime of the connection as a result
of commands from the network server.

Signed-off-by: Jordan Yates <[email protected]>

Author: Jordan Yates

include/lorawan/lorawan.h

@@ -205,6 +205,16 @@ void lorawan_enable_adr(bool enable);
  */
 int lorawan_set_datarate(enum lorawan_datarate dr);
 
+/**
+ * @brief Get the minimum possible datarate
+ *
+ * The minimum possible datarate may change in response to a TxParamSetupReq
+ * command from the network server.
+ *
+ * @return Minimum possible data rate
+ */
+enum lorawan_datarate lorawan_get_min_datarate(void);
+
 /**
  * @brief Get the current payload sizes
  *

subsys/lorawan/lorawan.c

@@ -361,6 +361,16 @@ void lorawan_get_payload_sizes(uint8_t *max_next_payload_size,
 	*max_payload_size = txInfo.CurrentPossiblePayloadSize;
 }
 
+enum lorawan_datarate lorawan_get_min_datarate(void)
+{
+	MibRequestConfirm_t mibGet;
+
+	mibGet.Type = MIB_CHANNELS_MIN_TX_DATARATE;
+	LoRaMacMibGetRequestConfirm(&mibGet);
+
+	return mibGet.Param.ChannelsMinTxDatarate;
+}
+
 void lorawan_enable_adr(bool enable)
 {
 	MibRequestConfirm_t mib_req;