Added copyright

u8g2_hal_rpi_i2c.cpp

@@ -3,6 +3,21 @@
  *  @brief U8g2 HAL implementation for Raspberry Pi I2C
  *  @file
  *  @author Tomoyuki Nakashima
+ *  @copyright Copyright 2021 Tomoyuki Nakashima  
+    <br>
+    Licensed under the Apache License, Version 2.0 (the "License");  
+    you may not use this file except in compliance with the License.  
+    You may obtain a copy of the License at  
+
+        http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software  
+    distributed under the License is distributed on an "AS IS" BASIS,  
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  
+    See the License for the specific language governing permissions and  
+    limitations under the License.  
+    <br>
+    See `LICENSE` in the project root for more information.
  */
 
 // u8g2 + external I/F of this file

u8g2_hal_rpi_i2c.h

@@ -3,8 +3,21 @@
  *  @brief U8g2 HAL implementation for Raspberry Pi I2C
  *  @file
  *  @author Tomoyuki Nakashima
- *  @remark For better U8g2 performance, you can change I2C bus speed to 400 kb/s with the following configuration. <br>
- *  /boot/config.txt: `dtparam=i2c_arm=on,i2c_arm_baudrate=400000`
+ *  @copyright Copyright 2021 Tomoyuki Nakashima  
+    <br>
+    Licensed under the Apache License, Version 2.0 (the "License");  
+    you may not use this file except in compliance with the License.  
+    You may obtain a copy of the License at  
+
+        http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software  
+    distributed under the License is distributed on an "AS IS" BASIS,  
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  
+    See the License for the specific language governing permissions and  
+    limitations under the License.  
+    <br>
+    See `LICENSE` in the project root for more information.
  */
 
 #ifndef U8G2DEMO_U8G2_HAL_RPI_I2C_H
@@ -28,6 +41,8 @@ struct u8g2_hal_rpi_i2c_config_t {
  *  Set I2C Configuration.
  *  @brief Set I2C Configuration
  *  @param param I2C Configuration
+ *  @remark For better U8g2 performance, you can change I2C bus speed to 400 kb/s with the following configuration. <br>
+ *  /boot/config.txt: `dtparam=i2c_arm=on,i2c_arm_baudrate=400000`
  */
 void u8g2_hal_rpi_i2c_set_config(u8g2_hal_rpi_i2c_config_t param);