cy_capsense_filter.c

/***************************************************************************//**
* \file cy_capsense_filter.c
* \version 2.0
*
* \brief
* This file contains the source code of all filters implementation.
*
********************************************************************************
* \copyright
* Copyright 2018-2019, Cypress Semiconductor Corporation.  All rights reserved.
* You may use this file only in accordance with the license, terms, conditions,
* disclaimers, and limitations in the end user license agreement accompanying
* the software package with which this file was provided.
*******************************************************************************/


#include <stddef.h>
#include "cy_capsense_filter.h"
#include "cy_capsense_common.h"
#include "cy_capsense_lib.h"

#if defined(CY_IP_MXCSDV2)


/*******************************************************************************
* Local definition
*******************************************************************************/
#define CY_CAPSENSE_IIR_BL_SHIFT                                (8u)

#define CY_CAPSENSE_IIR_SHIFT_STANDARD                          (0u)
#define CY_CAPSENSE_IIR_SHIFT_PERFORMANCE                       (8u)

#define CY_CAPSENSE_RC_MEDIAN_SIZE                              (2u)
#define CY_CAPSENSE_RC_IIR_SIZE                                 (1u)
#define CY_CAPSENSE_RC_AVG_SIZE                                 (3u)

/* IIR filter constant */
#define CY_CAPSENSE_IIR_COEFFICIENT_K                   (256u)


/*******************************************************************************
* Function Name: Cy_CapSense_UpdateAllBaselines
****************************************************************************//**
*
* Updates the baseline for all the sensors in all the widgets. 
* 
* Baselines must be updated after sensor scan to ignore low frequency 
* changes in the sensor data caused by environment changes such as 
* temperature from sensor status decision. 
* 
* This function ignores the widget enable bit in the widget status register.
* Calling this function multiple times without a new sensor scan leads to 
* unexpected behavior and should be avoided. 
* 
* This function is called by Cy_CapSense_ProcessAllWidgets() and 
* Cy_CapSense_ProcessWidget(), hence the application program need not use this  
* function if any of the above functions is already used. This function can be 
* used for custom application implementation.
* 
* \param context
* The pointer to the CapSense context structure \ref cy_stc_capsense_context_t.
*
* \return
* Returns the status of the update baseline operation of all the widgets:
* - CY_RET_SUCCESS  - The operation is successfully completed.
* - CY_RET_BAD_DATA - The baseline processing failed.
*
*******************************************************************************/
cy_status Cy_CapSense_UpdateAllBaselines(const cy_stc_capsense_context_t * context)
{
    uint32_t wdIndex;
    cy_status bslnStatus = CY_RET_SUCCESS;

    for(wdIndex = context->ptrCommonConfig->numWd; wdIndex-- > 0u;)
    {
        bslnStatus |= Cy_CapSense_UpdateWidgetBaseline(wdIndex, context);
    }

    return(bslnStatus);
}


/*******************************************************************************
* Function Name: Cy_CapSense_UpdateWidgetBaseline
****************************************************************************//**
*
* Updates the baselines for all the sensors in a widget specified by 
* the input parameter. 
* 
* This function performs exactly the same tasks as 
* Cy_CapSense_UpdateAllBaselines() but only for a specified widget.
* 
* Calling this function multiple times without a new sensor scan leads to 
* unexpected behavior and should be avoided. The application program need 
* not use this function if the Cy_CapSense_UpdateAllBaselines(), 
* Cy_CapSense_ProcessAllWidgets() or Cy_CapSense_ProcessWidget() functions 
* are already used.
*
* \param widgetId
* Specifies the ID number of the widget. A macro for the widget ID can be found 
* in the cycfg_capsense.h file defined as CY_CAPSENSE_<WIDGET_NAME>_WDGT_ID.
*
* \param context
* The pointer to the CapSense context structure \ref cy_stc_capsense_context_t.
*
* \return
* Returns the status of the specified widget update baseline operation:
* - CY_RET_SUCCESS - The operation is successfully completed.
* - CY_RET_BAD_DATA - The baseline processing failed.
*
*******************************************************************************/
cy_status Cy_CapSense_UpdateWidgetBaseline(
                uint32_t widgetId, 
                const cy_stc_capsense_context_t * context)
{
    uint32_t snsIndex;
    cy_status bslnStatus = CY_RET_SUCCESS;

    for(snsIndex = context->ptrWdConfig[widgetId].numSns; snsIndex-- > 0u;)
    {
        bslnStatus |= Cy_CapSense_UpdateSensorBaseline(widgetId, snsIndex, context);
    }

    return(bslnStatus);
}


/*******************************************************************************
* Function Name: Cy_CapSense_UpdateSensorBaseline
****************************************************************************//**
*
* Updates the baseline for a sensor in a widget specified by the 
* input parameters. 
* 
* This function performs exactly the same tasks as 
* Cy_CapSense_UpdateAllBaselines() and Cy_CapSense_UpdateWidgetBaseline() 
* but only for a specified sensor.
* 
* Calling this function multiple times without a new sensor scan leads to 
* unexpected behavior and should be avoided. The application need not use 
* this function if the Cy_CapSense_UpdateWidgetBaseline (), 
* Cy_CapSense_UpdateAllBaselines (), Cy_CapSense_ProcessAllWidgets(), 
* or Cy_CapSense_ProcessWidget() functions are already used.
*
* \param widgetId
* Specifies the ID number of the widget. A macro for the widget ID can be found 
* in the cycfg_capsense.h file defined as CY_CAPSENSE_<WIDGET_NAME>_WDGT_ID.
*
* \param sensorId
* Specifies the ID number of the sensor within the widget. A macro for the 
* sensor ID within a specified widget can be found in the cycfg_capsense.h 
* file defined as CY_CAPSENSE_<WIDGET_NAME>_SNS<SENSOR_NUMBER>_ID.
*
* \param context
* The pointer to the CapSense context structure \ref cy_stc_capsense_context_t.
*
* \return
* Returns the status of the specified sensor update baseline operation:
* - CY_RET_SUCCESS - The operation is successfully completed.
* - CY_RET_BAD_DATA - The baseline processing failed.
*
*******************************************************************************/
cy_status Cy_CapSense_UpdateSensorBaseline(
                uint32_t widgetId, 
                uint32_t sensorId, 
                const cy_stc_capsense_context_t * context)
{
    uint32_t result;
    const cy_stc_capsense_widget_config_t * ptrWdCfg = &context->ptrWdConfig[widgetId];

    result = Cy_CapSense_FtUpdateBaseline(ptrWdCfg->ptrWdContext, &ptrWdCfg->ptrSnsContext[sensorId], context);

    return (result);
}

/*******************************************************************************
* Function Name: Cy_CapSense_FtUpdateBaseline
****************************************************************************//**
*
* Updates the baseline for a sensor specified by an input parameter.
*
* Check a matching of present baseline and its inverse duplication. If they
* match, then the function updates the baseline for a sensor specified by an input parameter.
* If they don't match, the function returns CY_CAPSENSE_TST_BSLN_DUPLICATION
* result and doesn't update the baseline.
*
* \param ptrWdContext
* The pointer to the widget context structure where all the widget parameters
* are stored.
*
* \param ptrSnsContext
* The pointer to the sensor context structure where the sensor data
* is stored.
*
* \param context
* The pointer to the CapSense context structure \ref cy_stc_capsense_context_t.
*
* \return
* Returns a status indicating whether the baseline has been updated:
* - Zero - if baseline updating was successful.
* - Non-zero - if present sensor's any channel baseline and its inversion
* doesn't match.
*
*******************************************************************************/
uint32_t Cy_CapSense_FtUpdateBaseline(
                const cy_stc_capsense_widget_context_t * ptrWdContext,
                cy_stc_capsense_sensor_context_t * ptrSnsContext,
                const cy_stc_capsense_context_t * context)
{
    uint32_t result = CY_RET_SUCCESS;
    uint32_t bslnHistory;

    /* Reset negative baseline counter */
    if(ptrSnsContext->raw >= ptrSnsContext->bsln)
    {
        ptrSnsContext->negBslnRstCnt = 0u;
    }

    /* Reset baseline */
    if (ptrSnsContext->bsln > (ptrWdContext->nNoiseTh + ptrSnsContext->raw))
    {
        if (ptrSnsContext->negBslnRstCnt >= ptrWdContext->lowBslnRst)
        {
            Cy_CapSense_FtInitializeBaseline(ptrSnsContext);
        }
        else
        {
            ptrSnsContext->negBslnRstCnt++;
        }
    }
    else
    {
        /* 
        * Update baseline only if:
        * - signal is in range between noiseThreshold and negativenoiseThreshold
        * or
        * - sensor Auto-reset is enabled
        */
        if ((0u != context->ptrCommonConfig->swSensorAutoResetEn) || 
            (ptrSnsContext->raw <= (ptrWdContext->noiseTh + ptrSnsContext->bsln)))
        {
            /* Get real baseline */
            bslnHistory = ((uint32_t)ptrSnsContext->bsln << CY_CAPSENSE_IIR_BL_SHIFT) | ptrSnsContext->bslnExt;
            /* Calculate baseline value */
            bslnHistory = Cy_CapSense_FtIIR1stOrder((uint32_t)ptrSnsContext->raw << CY_CAPSENSE_IIR_BL_SHIFT, bslnHistory, (uint32_t)ptrWdContext->bslnCoeff);
            /* Split baseline */
            ptrSnsContext->bsln = CY_LO16(bslnHistory >> CY_CAPSENSE_IIR_BL_SHIFT);
            ptrSnsContext->bslnExt = CY_LO8(bslnHistory);
        }
    }
    return result;
}


/*******************************************************************************
* Function Name: Cy_CapSense_InitializeAllBaselines
****************************************************************************//**
*
* Initializes the baselines of all the sensors of all the widgets.
* 
* This function initializes baselines for all sensors and widgets in the project. 
* It can also be used to re-initialize baselines at any time, however, note 
* that all sensor data history information and sensor status shall be reset 
* along with re-initialization of baseline.
* 
* Following functions to initialize sensor and widgets and filter history 
* should be called after initializing baseline for proper operation of 
* the CapSense middleware:
* * Cy_CapSense_InitializeAllStatuses()
* * Cy_CapSense_InitializeAllFilters()
* 
* These functions are called by the CapSense_Enable() function, hence it is 
* not required to use this function if above function is used.
*
* \param context
* The pointer to the CapSense context structure \ref cy_stc_capsense_context_t.
*
*******************************************************************************/
void Cy_CapSense_InitializeAllBaselines(cy_stc_capsense_context_t * context)
{
    uint32_t wdIndex;

    for(wdIndex = context->ptrCommonConfig->numWd; wdIndex-- > 0u;)
    {
        Cy_CapSense_InitializeWidgetBaseline(wdIndex, context);
    }
}


/*******************************************************************************
* Function Name: Cy_CapSense_InitializeWidgetBaseline
****************************************************************************//**
*
* Initializes the baselines of all the sensors in a specific widget. 
* 
* This function initializes baselines for all sensors in a specific widget 
* in the project. It can also be used to re-initialize baselines at any time, 
* however, note that all sensor data history information and sensor status 
* should be reset along with re-initialization of baseline.
* 
* The following functions to initialize sensor and widgets and filter history 
* should be called after initializing baselines for proper operation of 
* middleware.
* * Cy_CapSense_InitializeWidgetStatus()
* * Cy_CapSense_InitializeWidgetFilter()
* 
* These functions are called by CapSense_Enable() function, hence it is not 
* required to use this function is above function is used.
* 
* \param widgetId
* Specifies the ID number of the widget. A macro for the widget ID can be found 
* in the cycfg_capsense.h file defined as CY_CAPSENSE_<WIDGET_NAME>_WDGT_ID.
*
* \param context
* The pointer to the CapSense context structure \ref cy_stc_capsense_context_t.
*
*******************************************************************************/
void Cy_CapSense_InitializeWidgetBaseline(
                uint32_t widgetId, 
                cy_stc_capsense_context_t * context)
{
    uint32_t snsIndex;

    for(snsIndex = context->ptrWdConfig[widgetId].numSns; snsIndex-- > 0u;)
    {
        Cy_CapSense_InitializeSensorBaseline(widgetId, snsIndex, context);
    }
}


/*******************************************************************************
* Function Name: Cy_CapSense_InitializeSensorBaseline
****************************************************************************//**
*
* Initializes the baseline of a sensor in a widget specified
* by the input parameters.
*
* \param widgetId
* Specifies the ID number of the widget. A macro for the widget ID can be found 
* in the cycfg_capsense.h file defined as CY_CAPSENSE_<WIDGET_NAME>_WDGT_ID.
*
* \param sensorId
* Specifies the ID number of the sensor within the widget. A macro for the 
* sensor ID within a specified widget can be found in the cycfg_capsense.h 
* file defined as CY_CAPSENSE_<WIDGET_NAME>_SNS<SENSOR_NUMBER>_ID.
*
* \param context
* The pointer to the CapSense context structure \ref cy_stc_capsense_context_t.
*
*******************************************************************************/
void Cy_CapSense_InitializeSensorBaseline(
                uint32_t widgetId, 
                uint32_t sensorId, 
                cy_stc_capsense_context_t * context)
{
    uint32_t freqChIndex;
    uint32_t freqChNumber;
    uint32_t cxtOffset;

    freqChNumber = (CY_CAPSENSE_ENABLE == context->ptrCommonConfig->mfsEn) ? 3u : 1u;
    for(freqChIndex = 0u; freqChIndex < freqChNumber; freqChIndex++)
    {
        cxtOffset = sensorId + (freqChIndex * context->ptrCommonConfig->numSns);
        Cy_CapSense_FtInitializeBaseline(&context->ptrWdConfig[widgetId].ptrSnsContext[cxtOffset]);
    }
}


/*******************************************************************************
* Function Name: Cy_CapSense_FtInitializeBaseline
****************************************************************************//**
*
* Initializes the baseline history for a sensor indicated by an input
* parameter.
*
* \param ptrSnsContext 
* The pointer to the sensor context structure.
*
*******************************************************************************/
void Cy_CapSense_FtInitializeBaseline(cy_stc_capsense_sensor_context_t * ptrSnsContext)
{
    ptrSnsContext->bslnExt = 0u;
    ptrSnsContext->bsln = ptrSnsContext->raw;
    ptrSnsContext->negBslnRstCnt = 0u;
}


/*******************************************************************************
* Function Name: Cy_CapSense_InitializeAllFilters
****************************************************************************//**
*
* Initializes (or re-initializes) all the firmware filter history, except 
* the baseline.
*
* Calling this function is accompanied by 
* * Cy_CapSense_InitializeAllStatuses()
* * Cy_CapSense_InitializeAllBaselines()
*
* \param context
* The pointer to the CapSense context structure \ref cy_stc_capsense_context_t.
*
*******************************************************************************/
void Cy_CapSense_InitializeAllFilters(const cy_stc_capsense_context_t * context)
{
    uint32_t widgetId;

    for(widgetId = context->ptrCommonConfig->numWd; widgetId-- > 0u;)
    {
        Cy_CapSense_InitializeWidgetFilter(widgetId, context);
    }
}


/*******************************************************************************
* Function Name: Cy_CapSense_InitializeWidgetFilter
****************************************************************************//**
*
* Initializes (or re-initializes) the raw count filter history of all 
* the sensors in a widget specified by the input parameter.
*
* Calling this function is accompanied by 
* - Cy_CapSense_InitializeWidgetStatus().
* - Cy_CapSense_InitializeWidgetBaseline().
*
* \param widgetId
* Specifies the ID number of the widget. A macro for the widget ID can be found 
* in the cycfg_capsense.h file defined as CY_CAPSENSE_<WIDGET_NAME>_WDGT_ID.
*
* \param context
* The pointer to the CapSense context structure \ref cy_stc_capsense_context_t.
*
*******************************************************************************/
void Cy_CapSense_InitializeWidgetFilter(
                uint32_t widgetId, 
                const cy_stc_capsense_context_t * context)
{
    uint32_t snsIndex;
    uint32_t freqChIndex;
    uint32_t freqChNumber;
    uint32_t snsHistorySize;
    uint32_t cxtOffset;
    uint32_t historyOffset;
        
    const cy_stc_capsense_widget_config_t * ptrWdCfg = &context->ptrWdConfig[widgetId];
    
    uint32_t rawFilterCfg = ptrWdCfg->rawFilterConfig;
    uint8_t * ptrHistoryLow = NULL;
    uint16_t * ptrHistory;
    cy_stc_capsense_sensor_context_t * ptrSnsCtx ;
    cy_stc_capsense_smartsense_csd_noise_envelope_t * ptrNEHistory;

    freqChNumber = (CY_CAPSENSE_ENABLE == context->ptrCommonConfig->mfsEn) ? 3u : 1u;
    snsHistorySize = (uint32_t)ptrWdCfg->rawFilterConfig & CY_CAPSENSE_RC_FILTER_SNS_HISTORY_SIZE_MASK;
    for(freqChIndex = 0u; freqChIndex < freqChNumber; freqChIndex++)
    {
        for(snsIndex = 0u; snsIndex < ptrWdCfg->numSns; snsIndex++)
        {
            cxtOffset = snsIndex + (freqChIndex * context->ptrCommonConfig->numSns);
            historyOffset = snsHistorySize * (snsIndex + (freqChIndex * context->ptrCommonConfig->numSns));
            ptrSnsCtx = &ptrWdCfg->ptrSnsContext[cxtOffset];
            ptrHistory = &ptrWdCfg->ptrRawFilterHistory[historyOffset];

            if(CY_CAPSENSE_IIR_FILTER_PERFORMANCE == (ptrWdCfg->rawFilterConfig & CY_CAPSENSE_RC_FILTER_IIR_MODE_MASK))
            {
                ptrHistoryLow = &ptrWdCfg->ptrRawFilterHistoryLow[cxtOffset];
            }

            if(0u != (CY_CAPSENSE_RC_FILTER_MEDIAN_EN_MASK & rawFilterCfg))
            {
                Cy_CapSense_InitializeMedianInternal(ptrWdCfg, ptrSnsCtx, ptrHistory);
                ptrHistory += CY_CAPSENSE_RC_MEDIAN_SIZE;
            }

            if(0u != (CY_CAPSENSE_RC_FILTER_IIR_EN_MASK & rawFilterCfg))
            {
                Cy_CapSense_InitializeIIRInternal(ptrWdCfg, ptrSnsCtx, ptrHistory, ptrHistoryLow);
                ptrHistory += CY_CAPSENSE_RC_IIR_SIZE;
            }
                
            if(0u != (CY_CAPSENSE_RC_FILTER_AVERAGE_EN_MASK & rawFilterCfg))
            {
                Cy_CapSense_InitializeAverageInternal(ptrWdCfg, ptrSnsCtx, ptrHistory);
            }
        }
    }
    
    if (CY_CAPSENSE_CSD_SS_HWTH_EN == context->ptrCommonConfig->csdAutotuneEn)
    {
        /* Noise envelope is available for CSD widgets only */
        if ((uint8_t)CY_CAPSENSE_SENSE_METHOD_CSD_E == ptrWdCfg->senseMethod)
        {
            ptrSnsCtx = ptrWdCfg->ptrSnsContext;
            ptrNEHistory = ptrWdCfg->ptrNoiseEnvelope;
            for(snsIndex = 0u; snsIndex < ptrWdCfg->numSns; snsIndex++)
            {
                Cy_CapSense_InitializeNoiseEnvelope_Lib_Call(ptrSnsCtx->raw,
                                                             ptrWdCfg->ptrWdContext->sigPFC,
                                                             ptrNEHistory,
                                                             context);
                ptrSnsCtx++;
                ptrNEHistory++;
            }
        }
    }
}


/*******************************************************************************
* Function Name: Cy_CapSense_InitializeIIR
****************************************************************************//**
*
* Initializes the IIR filter history.
*
* \param widgetId 
* Specifies the ID number of the widget. A macro for the widget ID can be found 
* in the cycfg_capsense.h file defined as CY_CAPSENSE_<WIDGET_NAME>_WDGT_ID.
*
* \param sensorId 
* Specifies the ID number of the sensor within the widget. A macro for the 
* sensor ID within a specified widget can be found in the cycfg_capsense.h 
* file defined as CY_CAPSENSE_<WIDGET_NAME>_SNS<SENSOR_NUMBER>_ID.
*
* \param context
* The pointer to the CapSense context structure \ref cy_stc_capsense_context_t.
*
*******************************************************************************/
void Cy_CapSense_InitializeIIR(
                uint32_t widgetId, 
                uint32_t sensorId, 
                const cy_stc_capsense_context_t * context)
{
    uint32_t snsHistorySize;
    const cy_stc_capsense_widget_config_t * ptrWdCfg;
    const cy_stc_capsense_sensor_context_t * ptrSnsCtx;
    
    ptrWdCfg = &context->ptrWdConfig[widgetId];
    ptrSnsCtx = &ptrWdCfg->ptrSnsContext[sensorId];
    snsHistorySize = (uint32_t)ptrWdCfg->rawFilterConfig & CY_CAPSENSE_RC_FILTER_SNS_HISTORY_SIZE_MASK;
    
    Cy_CapSense_InitializeIIRInternal(ptrWdCfg,
                                      ptrSnsCtx, 
                                      &ptrWdCfg->ptrRawFilterHistory[(sensorId * snsHistorySize) + 2uL],
                                      &ptrWdCfg->ptrRawFilterHistoryLow[sensorId]);
}


/*******************************************************************************
* Function Name: Cy_CapSense_RunIIR
****************************************************************************//**
*
* Executes the IIR filter algorithm on a sensor indicated by an input
* parameter.
*
* \param widgetId 
* Specifies the ID number of the widget. A macro for the widget ID can be found 
* in the cycfg_capsense.h file defined as CY_CAPSENSE_<WIDGET_NAME>_WDGT_ID.
*
* \param sensorId 
* Specifies the ID number of the sensor within the widget. A macro for the 
* sensor ID within a specified widget can be found in the cycfg_capsense.h 
* file defined as CY_CAPSENSE_<WIDGET_NAME>_SNS<SENSOR_NUMBER>_ID.
*
* \param context
* The pointer to the CapSense context structure \ref cy_stc_capsense_context_t.
*
*******************************************************************************/
void Cy_CapSense_RunIIR(
                uint32_t widgetId, 
                uint32_t sensorId, 
                const cy_stc_capsense_context_t * context)
{
    uint32_t snsHistorySize;
    const cy_stc_capsense_widget_config_t * ptrWdCfg;
    cy_stc_capsense_sensor_context_t * ptrSnsCtx;
    
    ptrWdCfg = &context->ptrWdConfig[widgetId];
    ptrSnsCtx = &ptrWdCfg->ptrSnsContext[sensorId];
    snsHistorySize = (uint32_t)ptrWdCfg->rawFilterConfig & CY_CAPSENSE_RC_FILTER_SNS_HISTORY_SIZE_MASK;

    
    Cy_CapSense_RunIIRInternal(ptrWdCfg,
                               ptrSnsCtx, 
                               &ptrWdCfg->ptrRawFilterHistory[(sensorId * snsHistorySize) + 2uL],
                               &ptrWdCfg->ptrRawFilterHistoryLow[sensorId]);

}

/*******************************************************************************
* Function Name: Cy_CapSense_InitializeIIRInternal
****************************************************************************//**
*
* Initializes the IIR filter history.
*
* \param ptrWdConfig 
* The pointer to the widget configuration structure.
*
* \param ptrSnsContext     
* The pointer to the sensor context structure.
*
* \param ptrSnsRawHistory           
* The pointer to the filter history of the sensor.
*
* \param ptrSnsRawHistoryLow           
* The pointer to the extended filter history of the sensor.
*
*******************************************************************************/
void Cy_CapSense_InitializeIIRInternal(
                const cy_stc_capsense_widget_config_t * ptrWdConfig,
                const cy_stc_capsense_sensor_context_t * ptrSnsContext,
                uint16_t * ptrSnsRawHistory,
                uint8_t * ptrSnsRawHistoryLow)
{
    ptrSnsRawHistory[0u] = ptrSnsContext->raw;
    
    if(CY_CAPSENSE_IIR_FILTER_PERFORMANCE == (ptrWdConfig->rawFilterConfig & CY_CAPSENSE_RC_FILTER_IIR_MODE_MASK))
    {
        ptrSnsRawHistoryLow[0u] = 0u;
    }
}


/*******************************************************************************
* Function Name: Cy_CapSense_RunIIRInternal
****************************************************************************//**
*
* Runs the IIR filter.
*
* \param ptrWdConfig 
* The pointer to the widget configuration structure.
*
* \param ptrSnsContext     
* The pointer to the sensor context structure.
*
* \param ptrSnsRawHistory           
* The pointer to the filter history of the sensor.
*
* \param ptrSnsRawHistoryLow           
* The pointer to the extended filter history of the sensor.
*
*******************************************************************************/
void Cy_CapSense_RunIIRInternal(
                const cy_stc_capsense_widget_config_t * ptrWdConfig,
                cy_stc_capsense_sensor_context_t * ptrSnsContext,
                uint16_t * ptrSnsRawHistory,
                uint8_t * ptrSnsRawHistoryLow)
{
    uint32_t tempHistory;
    uint32_t tempRaw;
    
    if(CY_CAPSENSE_IIR_FILTER_PERFORMANCE == (ptrWdConfig->rawFilterConfig & CY_CAPSENSE_RC_FILTER_IIR_MODE_MASK))
    {
        tempRaw = ((uint32_t)ptrSnsContext->raw) << CY_CAPSENSE_IIR_SHIFT_PERFORMANCE;
        tempHistory  = ((uint32_t)(*ptrSnsRawHistory)) << CY_CAPSENSE_IIR_SHIFT_PERFORMANCE;
        tempHistory |= (uint32_t)(*ptrSnsRawHistoryLow);
        tempRaw = Cy_CapSense_FtIIR1stOrder(tempRaw, tempHistory, ptrWdConfig->iirCoeff);
        *ptrSnsRawHistory = CY_LO16(tempRaw >> CY_CAPSENSE_IIR_SHIFT_PERFORMANCE);
        *ptrSnsRawHistoryLow = CY_LO8(tempRaw);
        ptrSnsContext->raw = CY_LO16(tempRaw >> CY_CAPSENSE_IIR_SHIFT_PERFORMANCE);
    }
    else
    {
        tempRaw = Cy_CapSense_FtIIR1stOrder((uint32_t)ptrSnsContext->raw, (uint32_t)(*ptrSnsRawHistory), ptrWdConfig->iirCoeff);
        *ptrSnsRawHistory = CY_LO16(tempRaw);
        ptrSnsContext->raw = *ptrSnsRawHistory;
    }
}


/*******************************************************************************
* Function Name: Cy_CapSense_InitializeMedian
****************************************************************************//**
*
* Initializes the median filter history.
*
* \param widgetId 
* Specifies the ID number of the widget. A macro for the widget ID can be found 
* in the cycfg_capsense.h file defined as CY_CAPSENSE_<WIDGET_NAME>_WDGT_ID.
*
* \param sensorId 
* Specifies the ID number of the sensor within the widget. A macro for the 
* sensor ID within a specified widget can be found in the cycfg_capsense.h 
* file defined as CY_CAPSENSE_<WIDGET_NAME>_SNS<SENSOR_NUMBER>_ID.
*
* \param context
* The pointer to the CapSense context structure \ref cy_stc_capsense_context_t.
*
*******************************************************************************/
void Cy_CapSense_InitializeMedian(
                uint32_t widgetId, 
                uint32_t sensorId, 
                const cy_stc_capsense_context_t * context)
{
    uint32_t snsHistorySize;
    const cy_stc_capsense_widget_config_t * ptrWdCfg = &context->ptrWdConfig[widgetId];
    cy_stc_capsense_sensor_context_t * ptrSnsCtx = &ptrWdCfg->ptrSnsContext[sensorId];

    snsHistorySize = (uint32_t)ptrWdCfg->rawFilterConfig & CY_CAPSENSE_RC_FILTER_SNS_HISTORY_SIZE_MASK;
    
    Cy_CapSense_InitializeMedianInternal(ptrWdCfg,
                                         ptrSnsCtx,
                                         &ptrWdCfg->ptrRawFilterHistory[sensorId * snsHistorySize]);
}


/*******************************************************************************
* Function Name: Cy_CapSense_RunMedian
****************************************************************************//**
*
* Executes the median filter algorithm on a sensor raw count indicated by 
* the input parameters.
*
* \param widgetId 
* Specifies the ID number of the widget. A macro for the widget ID can be found 
* in the cycfg_capsense.h file defined as CY_CAPSENSE_<WIDGET_NAME>_WDGT_ID.
*
* \param sensorId
* Specifies the ID number of the sensor within the widget. A macro for the 
* sensor ID within a specified widget can be found in the cycfg_capsense.h 
* file defined as CY_CAPSENSE_<WIDGET_NAME>_SNS<SENSOR_NUMBER>_ID.
*
* \param context
* The pointer to the CapSense context structure \ref cy_stc_capsense_context_t.
*
*******************************************************************************/
void Cy_CapSense_RunMedian(
                uint32_t widgetId, 
                uint32_t sensorId, 
                const cy_stc_capsense_context_t * context)
{
    uint32_t snsHistorySize;
    const cy_stc_capsense_widget_config_t * ptrWdCfg = &context->ptrWdConfig[widgetId];
    cy_stc_capsense_sensor_context_t * ptrSnsCtx = &ptrWdCfg->ptrSnsContext[sensorId];

    snsHistorySize = (uint32_t)ptrWdCfg->rawFilterConfig & CY_CAPSENSE_RC_FILTER_SNS_HISTORY_SIZE_MASK;
    
    Cy_CapSense_RunMedianInternal(ptrWdCfg,
                                  ptrSnsCtx,

                                  &ptrWdCfg->ptrRawFilterHistory[sensorId * snsHistorySize]);
}


/*******************************************************************************
* Function Name: Cy_CapSense_InitializeMedianInternal
****************************************************************************//**
*
* Initializes the median filter.
*
* \param ptrWdConfig 
* The pointer to the widget configuration structure.
*
* \param ptrSnsContext     
* The pointer to the sensor context structure.
*
* \param ptrSnsRawHistory           
* The pointer to the filter history of the sensor.
*
*******************************************************************************/
void Cy_CapSense_InitializeMedianInternal(
                const cy_stc_capsense_widget_config_t * ptrWdConfig,
                const cy_stc_capsense_sensor_context_t * ptrSnsContext,
                uint16_t * ptrSnsRawHistory)
{
    (void)ptrWdConfig;
    
    ptrSnsRawHistory[0u] = ptrSnsContext->raw;
    ptrSnsRawHistory[1u] = ptrSnsContext->raw;
}


/*******************************************************************************
* Function Name: Cy_CapSense_RunMedianInternal
****************************************************************************//**
*
* Runs the median filter.
*
* \param ptrWdConfig 
* The pointer to the widget configuration structure.
*
* \param ptrSnsContext     
* The pointer to the sensor context structure.
*
* \param ptrSnsRawHistory           
* The pointer to the filter history of the sensor.
*
*******************************************************************************/
void Cy_CapSense_RunMedianInternal(
                const cy_stc_capsense_widget_config_t * ptrWdConfig,
                cy_stc_capsense_sensor_context_t * ptrSnsContext,
                uint16_t * ptrSnsRawHistory)
{
    uint32_t temp = Cy_CapSense_FtMedian(
                    (uint32_t)ptrSnsContext->raw, 
                    (uint32_t)ptrSnsRawHistory[0u], 
                    (uint32_t)ptrSnsRawHistory[1u]);
    
    (void)ptrWdConfig;
    
    ptrSnsRawHistory[1u] = ptrSnsRawHistory[0u];
    ptrSnsRawHistory[0u] = ptrSnsContext->raw;
    ptrSnsContext->raw = CY_LO16(temp);
}


/*******************************************************************************
* Function Name: Cy_CapSense_InitializeAverage
****************************************************************************//**
*
* Initializes the average filter history.
*
* \param widgetId 
* Specifies the ID number of the widget. A macro for the widget ID can be found 
* in the cycfg_capsense.h file defined as CY_CAPSENSE_<WIDGET_NAME>_WDGT_ID.
*
* \param sensorId 
* Specifies the ID number of the sensor within the widget. A macro for the 
* sensor ID within a specified widget can be found in the cycfg_capsense.h 
* file defined as CY_CAPSENSE_<WIDGET_NAME>_SNS<SENSOR_NUMBER>_ID.
*
* \param context
* The pointer to the CapSense context structure \ref cy_stc_capsense_context_t.
*
*******************************************************************************/
void Cy_CapSense_InitializeAverage(
                uint32_t widgetId, 
                uint32_t sensorId, 
                const cy_stc_capsense_context_t * context)
{
    uint32_t snsHistorySize;
    const cy_stc_capsense_widget_config_t  * ptrWdCfg;
    const cy_stc_capsense_sensor_context_t * ptrSnsCtx;
    
    ptrWdCfg   = &context->ptrWdConfig[widgetId];
    ptrSnsCtx  = &ptrWdCfg->ptrSnsContext[sensorId];
    snsHistorySize = (uint32_t)ptrWdCfg->rawFilterConfig & CY_CAPSENSE_RC_FILTER_SNS_HISTORY_SIZE_MASK;

    Cy_CapSense_InitializeAverageInternal(
                    ptrWdCfg,
                    ptrSnsCtx,
                    &ptrWdCfg->ptrRawFilterHistory[(sensorId * snsHistorySize) + 2u + 1u]);
}


/*******************************************************************************
* Function Name: Cy_CapSense_RunAverage
****************************************************************************//**
*
* Executes the average filter algorithm on a sensor indicated by an input
* parameter.
*
* \param widgetId 
* Specifies the ID number of the widget. A macro for the widget ID can be found 
* in the cycfg_capsense.h file defined as CY_CAPSENSE_<WIDGET_NAME>_WDGT_ID.
*
* \param sensorId 
* Specifies the ID number of the sensor within the widget. A macro for the 
* sensor ID within a specified widget can be found in the cycfg_capsense.h 
* file defined as CY_CAPSENSE_<WIDGET_NAME>_SNS<SENSOR_NUMBER>_ID.
*
* \param context
* The pointer to the CapSense context structure \ref cy_stc_capsense_context_t.
*
*******************************************************************************/
void Cy_CapSense_RunAverage(
                uint32_t widgetId, 
                uint32_t sensorId, 
                const cy_stc_capsense_context_t * context)
{
    uint32_t snsHistorySize;
    const cy_stc_capsense_widget_config_t * ptrWdCfg;
    cy_stc_capsense_sensor_context_t * ptrSnsCtx;
    
    ptrWdCfg   = &context->ptrWdConfig[widgetId];
    ptrSnsCtx  = &ptrWdCfg->ptrSnsContext[sensorId];
    snsHistorySize = (uint32_t)ptrWdCfg->rawFilterConfig & CY_CAPSENSE_RC_FILTER_SNS_HISTORY_SIZE_MASK;

    Cy_CapSense_RunAverageInternal(
                    ptrWdCfg,
                    ptrSnsCtx,
                    &ptrWdCfg->ptrRawFilterHistory[(sensorId * snsHistorySize) + 2u + 1u]);

}


/*******************************************************************************
* Function Name: Cy_CapSense_InitializeAverageInternal
****************************************************************************//**
*
* Initializes the average filter.
*
* \param ptrWdConfig 
* The pointer to the widget configuration structure.
*
* \param ptrSnsContext     
* The pointer to the sensor context structure.
*
* \param ptrSnsRawHistory           
* The pointer to the filter history of the sensor.
*
*******************************************************************************/
void Cy_CapSense_InitializeAverageInternal(
                const cy_stc_capsense_widget_config_t * ptrWdConfig,
                const cy_stc_capsense_sensor_context_t * ptrSnsContext,
                uint16_t * ptrSnsRawHistory)
{
    (void)ptrWdConfig;
    ptrSnsRawHistory[0u] = ptrSnsContext->raw;
    ptrSnsRawHistory[1u] = ptrSnsContext->raw;    
    ptrSnsRawHistory[2u] = ptrSnsContext->raw;
}


/*******************************************************************************
* Function Name: Cy_CapSense_RunAverageInternal
****************************************************************************//**
*
* Runs the average filter.
*
* \param ptrWdConfig 
* The pointer to the widget configuration structure.
*
* \param ptrSnsContext     
* The pointer to the sensor context structure.
*
* \param ptrSnsRawHistory           
* The pointer to the filter history of the sensor.
*
*******************************************************************************/
void Cy_CapSense_RunAverageInternal(
                const cy_stc_capsense_widget_config_t * ptrWdConfig,
                cy_stc_capsense_sensor_context_t * ptrSnsContext,
                uint16_t * ptrSnsRawHistory)
{
    uint32_t temp;

    if(CY_CAPSENSE_AVERAGE_FILTER_LEN_4 == (ptrWdConfig->rawFilterConfig & CY_CAPSENSE_RC_FILTER_AVERAGE_MODE_MASK))
    {
        temp = ((uint32_t)ptrSnsContext->raw + ptrSnsRawHistory[0u] + ptrSnsRawHistory[1u] + ptrSnsRawHistory[2u]) >> 2u;
        ptrSnsRawHistory[2u] = ptrSnsRawHistory[1u];
        ptrSnsRawHistory[1u] = ptrSnsRawHistory[0u];
    }
    else
    {
        temp = ((uint32_t)ptrSnsContext->raw + ptrSnsRawHistory[0u]) >> 1u;
    }
    ptrSnsRawHistory[0u] = ptrSnsContext->raw;
    ptrSnsContext->raw = CY_LO16(temp);
}


/*******************************************************************************
* Function Name: Cy_CapSense_FtRunEnabledFiltersInternal
****************************************************************************//**
*
* Runs all enabled filters.
*
* \param ptrWdConfig 
* The pointer to the widget configuration structure.
*
* \param ptrSnsContext     
* The pointer to the sensor context structure.
*
* \param ptrSnsRawHistory           
* The pointer to the filter history of the sensor.
*
* \param ptrSnsRawHistoryLow           
* The pointer to the extended filter history of the sensor.
*
*******************************************************************************/
void Cy_CapSense_FtRunEnabledFiltersInternal(
                const cy_stc_capsense_widget_config_t * ptrWdConfig,
                cy_stc_capsense_sensor_context_t * ptrSnsContext,
                uint16_t * ptrSnsRawHistory,
                uint8_t * ptrSnsRawHistoryLow)
{
    uint16_t rawFilterCfg;
    rawFilterCfg = ptrWdConfig->rawFilterConfig;
    
    if(0u != (CY_CAPSENSE_RC_FILTER_MEDIAN_EN_MASK & rawFilterCfg))
    {
        Cy_CapSense_RunMedianInternal(ptrWdConfig, ptrSnsContext, ptrSnsRawHistory);
        ptrSnsRawHistory += CY_CAPSENSE_RC_MEDIAN_SIZE;
    }

    if(0u != (CY_CAPSENSE_RC_FILTER_IIR_EN_MASK & rawFilterCfg))
    {
        Cy_CapSense_RunIIRInternal(ptrWdConfig, ptrSnsContext, ptrSnsRawHistory, ptrSnsRawHistoryLow);
        ptrSnsRawHistory += CY_CAPSENSE_RC_IIR_SIZE;
    }
        
    if(0u != (CY_CAPSENSE_RC_FILTER_AVERAGE_EN_MASK & rawFilterCfg))
    {
        Cy_CapSense_RunAverageInternal(ptrWdConfig, ptrSnsContext, ptrSnsRawHistory);
    }
}


/*******************************************************************************
* Function Name: Cy_CapSense_FtMedian
****************************************************************************//**
*
* Returns the median value from the three passed arguments.
*
* \param x1 
* The first value to be compared.
*
* \param x2 
* The second value to be compared.
*
* \param x3 
* The third value to be compared.
*
* \return   
* Returns the median value of input arguments.
*
*******************************************************************************/
uint32_t Cy_CapSense_FtMedian(uint32_t x1, uint32_t x2, uint32_t x3)
{
    uint32_t tmp;

    if (x1 > x2)
    {
        tmp = x2;
        x2 = x1;
        x1 = tmp;
    }

    if (x2 > x3)
    {
        x2 = x3;
    }

    return ((x1 > x2) ? x1 : x2);
}


/*******************************************************************************
* Function Name: Cy_CapSense_FtIIR1stOrder
****************************************************************************//**
*
* Returns the filtered data by the IIR 1-st order algorithm
*
* \param input      
* The data to be filtered.
*
* \param prevOutput 
* The previous filtered data.
*
* \param n          
* The IIR filter coefficient (n/256).
*
* \return   
* Returns the filtered data.
*
*******************************************************************************/
uint32_t Cy_CapSense_FtIIR1stOrder(uint32_t input, uint32_t prevOutput, uint32_t n)
{
    uint32_t filteredOutput;

    filteredOutput = ((n * input) + ((CY_CAPSENSE_IIR_COEFFICIENT_K - n) * prevOutput)) >> 8u;

    return filteredOutput;
}


/*******************************************************************************
* Function Name: Cy_CapSense_FtJitter
****************************************************************************//**
*
* Returns the filtered data by the jitter algorithm.
*
* \param input      
* The data to be filtered.
*
* \param prevOutput 
* The previous filtered data.
*
* \return   
* Returns the filtered data.
*
*******************************************************************************/
uint32_t Cy_CapSense_FtJitter(uint32_t input, uint32_t prevOutput)
{
    if (prevOutput > input)
    {
        input++;
    }
    else if (prevOutput < input)
    {
        input--;
    }
    else
    {
        /* Nothing to do - MISRA 14.1 requirement*/
    }
    return input;
}

#endif /* CY_IP_MXCSDV2 */


/* [] END OF FILE */