text: /**
    ******************************************************************************
    * @file    stm32f4xx_hal_i2c_ex.c
    * @author  MCD Application Team
    * @version V1.7.1
    * @date    14-April-2017
    * @brief   I2C Extension HAL module driver.
    *          This file provides firmware functions to manage the following 
    *          functionalities of I2C extension peripheral:
    *           + Extension features functions
    *    
    @verbatim
    ==============================================================================
                 ##### I2C peripheral extension features  #####
    ==============================================================================
             
    [..] Comparing to other previous devices, the I2C interface for STM32F427xx/437xx/ 
         429xx/439xx devices contains the following additional features :
         
         (+) Possibility to disable or enable Analog Noise Filter
         (+) Use of a configured Digital Noise Filter
     
                       ##### How to use this driver #####
    ==============================================================================
    [..] This driver provides functions to configure Noise Filter
      (#) Configure I2C Analog noise filter using the function HAL_I2C_AnalogFilter_Config()
      (#) Configure I2C Digital noise filter using the function HAL_I2C_DigitalFilter_Config()
    
    @endverbatim
    ******************************************************************************
    * @attention
    *
    * <h2><center>&copy; COPYRIGHT(c) 2017 STMicroelectronics</center></h2>
    *
    * Redistribution and use in source and binary forms, with or without modification,
    * are permitted provided that the following conditions are met:
    *   1. Redistributions of source code must retain the above copyright notice,
    *      this list of conditions and the following disclaimer.
    *   2. Redistributions in binary form must reproduce the above copyright notice,
    *      this list of conditions and the following disclaimer in the documentation
    *      and/or other materials provided with the distribution.
    *   3. Neither the name of STMicroelectronics nor the names of its contributors
    *      may be used to endorse or promote products derived from this software
    *      without specific prior written permission.
    *
    * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
    * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
    * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
    * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
    * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
    * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
    * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
    * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    *
    ******************************************************************************
    */ 
  
  /* Includes ------------------------------------------------------------------*/
  #include "stm32f4xx_hal.h"
  
  /** @addtogroup STM32F4xx_HAL_Driver
    * @{
    */
  
  /** @defgroup I2CEx I2CEx
    * @brief I2C HAL module driver
    * @{
    */
  
  #ifdef HAL_I2C_MODULE_ENABLED
  
  #if defined(STM32F427xx) || defined(STM32F437xx) || defined(STM32F429xx) || defined(STM32F439xx) ||\
      defined(STM32F401xC) || defined(STM32F401xE) || defined(STM32F411xE) || defined(STM32F446xx) ||\
      defined(STM32F469xx) || defined(STM32F479xx) || defined(STM32F413xx) || defined(STM32F423xx)
  /* Private typedef -----------------------------------------------------------*/
  /* Private define ------------------------------------------------------------*/
  /* Private macro -------------------------------------------------------------*/
  /* Private variables ---------------------------------------------------------*/
  /* Private function prototypes -----------------------------------------------*/
  /* Exported functions --------------------------------------------------------*/
  /** @defgroup I2CEx_Exported_Functions I2C Exported Functions
    * @{
    */
  
  
  /** @defgroup I2CEx_Exported_Functions_Group1 Extension features functions 
   *  @brief   Extension features functions 
   *
  @verbatim   
   ===============================================================================
                        ##### Extension features functions #####
   ===============================================================================  
      [..] This section provides functions allowing to:
        (+) Configure Noise Filters 
  
  @endverbatim
    * @{
    */
    
  /**
    * @brief  Configures I2C Analog noise filter. 
    * @param  hi2c: pointer to a I2C_HandleTypeDef structure that contains
    *                the configuration information for the specified I2Cx peripheral.
    * @param  AnalogFilter: new state of the Analog filter.
    * @retval HAL status
    */
  HAL_StatusTypeDef HAL_I2CEx_ConfigAnalogFilter(I2C_HandleTypeDef *hi2c, uint32_t AnalogFilter)
  {
    /* Check the parameters */
    assert_param(IS_I2C_ALL_INSTANCE(hi2c->Instance));
    assert_param(IS_I2C_ANALOG_FILTER(AnalogFilter));
    
    if(hi2c->State == HAL_I2C_STATE_READY)
    {
      hi2c->State = HAL_I2C_STATE_BUSY;
  
      /* Disable the selected I2C peripheral */
      __HAL_I2C_DISABLE(hi2c);    
  
      /* Reset I2Cx ANOFF bit */
      hi2c->Instance->FLTR &= ~(I2C_FLTR_ANOFF);
  
      /* Disable the analog filter */
      hi2c->Instance->FLTR |= AnalogFilter;
  
      __HAL_I2C_ENABLE(hi2c); 
  
      hi2c->State = HAL_I2C_STATE_READY;
  
      return HAL_OK;
    }
    else
    {
      return HAL_BUSY;
    }
  }
  
  /**
    * @brief  Configures I2C Digital noise filter. 
    * @param  hi2c: pointer to a I2C_HandleTypeDef structure that contains
    *                the configuration information for the specified I2Cx peripheral.
    * @param  DigitalFilter: Coefficient of digital noise filter between 0x00 and 0x0F.
    * @retval HAL status
    */
  HAL_StatusTypeDef HAL_I2CEx_ConfigDigitalFilter(I2C_HandleTypeDef *hi2c, uint32_t DigitalFilter)
  {
    uint16_t tmpreg = 0;
  
    /* Check the parameters */
    assert_param(IS_I2C_ALL_INSTANCE(hi2c->Instance));
    assert_param(IS_I2C_DIGITAL_FILTER(DigitalFilter));
    
    if(hi2c->State == HAL_I2C_STATE_READY)
    {
      hi2c->State = HAL_I2C_STATE_BUSY;
      
      /* Disable the selected I2C peripheral */
      __HAL_I2C_DISABLE(hi2c);  
      
      /* Get the old register value */
      tmpreg = hi2c->Instance->FLTR;
      
      /* Reset I2Cx DNF bit [3:0] */
      tmpreg &= ~(I2C_FLTR_DNF);
      
      /* Set I2Cx DNF coefficient */
      tmpreg |= DigitalFilter;
      
      /* Store the new register value */
      hi2c->Instance->FLTR = tmpreg;
      
      __HAL_I2C_ENABLE(hi2c); 
      
      hi2c->State = HAL_I2C_STATE_READY;
      
      return HAL_OK; 
    }
    else
    {
      return HAL_BUSY; 
    }
  }  
  
  /**
    * @}
    */
  
  /**
    * @}
    */  
  #endif /* STM32F427xx || STM32F429xx || STM32F437xx || STM32F439xx || STM32F401xC ||\
            STM32F401xE || STM32F446xx || STM32F469xx || STM32F479xx || STM32F413xx ||\
  		  STM32F423xx */
  
  #endif /* HAL_I2C_MODULE_ENABLED */
  /**
    * @}
    */
  
  /**
    * @}
    */
  
  /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
  