lorawan: rename lorawan_set_battery_level_callback and make it void

Rename the lorawan_set_battery_level_callback to
lorawan_register_battery_level_callback to make it consistent with other
functions for downlink and data rate changed callbacks.

Also making the function void for consistency. The get_battery_level
already checks if the callback is NULL before invoking it.

Signed-off-by: Martin Jäger <[email protected]>

Author: martinjaeger

doc/releases/migration-guide-3.6.rst

@@ -73,6 +73,14 @@ Bluetooth
   been renamed, from ``samples/bluetooth/hci_rpmsg`` to
   ``samples/bluetooth/hci_ipc``.
 
+LoRaWAN
+=======
+
+* The API to register a callback to provide battery level information to the LoRaWAN stack has been
+  renamed from ``lorawan_set_battery_level_callback`` to
+  :c:func:`lorawan_register_battery_level_callback` and the return type is now ``void``. This
+  is more consistent with similar functions for downlink and data rate changed callbacks.
+
 Networking
 ==========
 

include/zephyr/lorawan/lorawan.h

@@ -187,10 +187,8 @@ struct lorawan_downlink_cb {
  * Should no callback be provided the lorawan backend will report 255.
  *
  * @param battery_lvl_cb Pointer to the battery level function
- *
- * @return 0 if successful, negative errno code if failure
  */
-int lorawan_set_battery_level_callback(uint8_t (*battery_lvl_cb)(void));
+void lorawan_register_battery_level_callback(uint8_t (*battery_lvl_cb)(void));
 
 /**
  * @brief Register a callback to be run on downlink packets

subsys/lorawan/lorawan.c

@@ -621,15 +621,9 @@ int lorawan_send(uint8_t port, uint8_t *data, uint8_t len,
 	return ret;
 }
 
-int lorawan_set_battery_level_callback(uint8_t (*battery_lvl_cb)(void))
+void lorawan_register_battery_level_callback(uint8_t (*battery_lvl_cb)(void))
 {
-	if (battery_lvl_cb == NULL) {
-		return -EINVAL;
-	}
-
 	get_battery_level_user = battery_lvl_cb;
-
-	return 0;
 }
 
 void lorawan_register_downlink_callback(struct lorawan_downlink_cb *cb)