Merge pull request #480 from tropicsquare/ETR01SDK-563-Docs-mention-that-lt_deinit-and-lt_init-has-to-be-called-after-FW-update

ETR01SDK-563: Mention that lt_deinit and lt_init has to be called after FW update

Author: medexs

docs/common/examples_descriptions/fw_update.md

@@ -3,6 +3,9 @@ This example explains the firmware update process for both ABAB and ACAB silicon
 - How to read the current firmware versions.
 - How to update the firmware using `lt_do_mutable_fw_update()`.
 
+    !!! info "Updating FW with `lt_do_mutable_fw_update()` in Your Application"
+        If you are using `lt_do_mutable_fw_update()` in your application to update TROPIC01's FW, make sure to reinitialize the handle (`lt_handle_t`) after the function returns successfully, i.e. call `lt_deinit()` and `lt_init()`.
+
 !!! info "TROPIC01 Firmware"
     For more information about the firmware itself, refer to the [TROPIC01 Firmware](/reference/tropic01_fw.md) section.
 

include/libtropic.h

@@ -28,8 +28,8 @@ extern "C" {
 
 /**
  * @brief Initialize handle and transport layer.
- * @note If the function fails, `lt_deinit` must not be called. In this case, the function handles the
- * cleanup itself.
+ * @note If the function fails, `lt_deinit()` must not be called. In this case, the function handles
+ * the cleanup itself.
  *
  * @param h           Handle for communication with TROPIC01
  *
@@ -794,6 +794,8 @@ lt_ret_t lt_print_fw_header(lt_handle_t *h, const lt_bank_id_t bank_id,
 
 /**
  * @brief Performs mutable firmware update on ABAB and ACAB silicon revisions.
+ * @important After this function returns successfully, the handle (`lt_handle_t`) has to be
+ * initialized again (i.e. calling `lt_deinit()` and `lt_init()`).
  *
  * @param h                 Handle for communication with TROPIC01
  * @param update_data       Pointer to the data to be written