freemodbus: fix invalid error handling for duplicate param_key

components/freemodbus/common/include/esp_modbus_master.h

@@ -208,7 +208,7 @@ esp_err_t mbc_master_get_cid_info(uint16_t cid, const mb_parameter_descriptor_t*
  * @return
  *     - esp_err_t ESP_OK - request was successful and value buffer contains
  *                          representation of actual parameter data from slave
- *     - esp_err_t ESP_ERR_INVALID_ARG - invalid argument of function
+ *     - esp_err_t ESP_ERR_INVALID_ARG - invalid argument of function or parameter descriptor
  *     - esp_err_t ESP_ERR_INVALID_RESPONSE - an invalid response from slave
  *     - esp_err_t ESP_ERR_INVALID_STATE - invalid state during data processing or allocation failure
  *     - esp_err_t ESP_ERR_TIMEOUT - operation timed out and no response from slave
@@ -229,7 +229,7 @@ esp_err_t mbc_master_get_parameter(uint16_t cid, char* name, uint8_t* value, uin
  *
  * @return
  *     - esp_err_t ESP_OK - request was successful and value was saved in the slave device registers
- *     - esp_err_t ESP_ERR_INVALID_ARG - invalid argument of function
+ *     - esp_err_t ESP_ERR_INVALID_ARG - invalid argument of function or parameter descriptor
  *     - esp_err_t ESP_ERR_INVALID_RESPONSE - an invalid response from slave during processing of parameter
  *     - esp_err_t ESP_ERR_INVALID_STATE - invalid state during data processing or allocation failure
  *     - esp_err_t ESP_ERR_TIMEOUT - operation timed out and no response from slave

components/freemodbus/serial_master/modbus_controller/mbc_serial_master.c

@@ -451,8 +451,9 @@ static esp_err_t mbc_serial_master_get_parameter(uint16_t cid, char* name,
         // Set the type of parameter found in the table
         *type = reg_info.param_type;
     } else {
-        ESP_LOGD(MB_MASTER_TAG, "%s: The cid(%u) not found in the data dictionary.",
+        ESP_LOGE(MB_MASTER_TAG, "%s: The cid(%u) not found in the data dictionary.",
                                                     __FUNCTION__, reg_info.cid);
+        error = ESP_ERR_INVALID_ARG;
     }
     return error;
 }
@@ -493,6 +494,7 @@ static esp_err_t mbc_serial_master_set_parameter(uint16_t cid, char* name,
     } else {
         ESP_LOGE(MB_MASTER_TAG, "%s: The requested cid(%u) not found in the data dictionary.",
                                     __FUNCTION__, reg_info.cid);
+        error = ESP_ERR_INVALID_ARG;
     }
     return error;
 }