Compiler/CC2541: Stopwatch

/******************************************************************************

 @file  battservice.c

 @brief This file contains the Battery service.

 Group: WCS, BTS
 Target Device: CC2540, CC2541

 ******************************************************************************
 
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 All rights reserved.

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 ******************************************************************************
 Release Name: ble_sdk_1.5.1.1
 Release Date: 2020-01-30 19:28:56
 *****************************************************************************/

/*********************************************************************
 * INCLUDES
 */
#include "bcomdef.h"
#include "OSAL.h"
#include "hal_adc.h"
#include "linkdb.h"
#include "att.h"
#include "gatt.h"
#include "gatt_uuid.h"
#include "gatt_profile_uuid.h"
#include "gattservapp.h"
#include "hiddev.h"
#include "battservice.h"


/*********************************************************************
 * MACROS
 */

/*********************************************************************
 * CONSTANTS
 */

// ADC voltage levels
#define BATT_ADC_LEVEL_4V           1700
#define BATT_ADC_LEVEL_2V           1250

#define BATT_LEVEL_VALUE_IDX        2 // Position of battery level in attribute array
#define BATT_LEVEL_VALUE_CCCD_IDX   3 // Position of battery level CCCD in attribute array

#define BATT_LEVEL_VALUE_LEN        1

/**
 * GATT Characteristic Descriptions
 */
#define GATT_DESC_LENGTH_UUID            0x3111 // Used with Unit percent
uint16 v=0;

/*********************************************************************
 * TYPEDEFS
 */

/*********************************************************************
 * GLOBAL VARIABLES
 */
// Battery service
CONST uint8 battServUUID[ATT_BT_UUID_SIZE] =
{
  LO_UINT16(BATT_SERV_UUID), HI_UINT16(BATT_SERV_UUID)
};

// Battery level characteristic
CONST uint8 battLevelUUID[ATT_BT_UUID_SIZE] =
{
  LO_UINT16(BATT_LEVEL_UUID), HI_UINT16(BATT_LEVEL_UUID)
};

/*********************************************************************
 * EXTERNAL VARIABLES
 */

/*********************************************************************
 * EXTERNAL FUNCTIONS
 */

/*********************************************************************
 * LOCAL VARIABLES
 */

// Application callback
static battServiceCB_t battServiceCB;

// Measurement setup callback
static battServiceSetupCB_t battServiceSetupCB = NULL;

// Measurement teardown callback
static battServiceTeardownCB_t battServiceTeardownCB = NULL;

// Measurement calculation callback
static battServiceCalcCB_t battServiceCalcCB = NULL;

static uint16 battMinLevel = BATT_ADC_LEVEL_2V; // For VDD/3 measurements
static uint16 battMaxLevel = BATT_ADC_LEVEL_4V; // For VDD/3 measurements

// Critical battery level setting
static uint8 battCriticalLevel;

// ADC channel to be used for reading
static uint8 battServiceAdcCh = HAL_ADC_CHN_AIN7;

/*********************************************************************
 * Profile Attributes - variables
 */

// Battery Service attribute
static CONST gattAttrType_t battService = { ATT_BT_UUID_SIZE, battServUUID };

// Battery level characteristic
static uint8 battLevelProps = GATT_PROP_READ | GATT_PROP_NOTIFY;
static uint8 battLevel = 100;
static gattCharCfg_t *battLevelClientCharCfg;

// Characteristic Presentation Format of the Battery Level Characteristic.
static gattCharFormat_t battLevelPresentation = {
  GATT_FORMAT_UINT8,           /* format */
  0,                           /* exponent */
  GATT_UNIT_PERCENTAGE_UUID,   /* unit */
  GATT_NS_BT_SIG,              /* name space */
  GATT_DESC_LENGTH_UUID        /* desc */
};

// HID Report Reference characteristic descriptor, battery level
static uint8 hidReportRefBattLevel[HID_REPORT_REF_LEN] =
             { HID_RPT_ID_BATT_LEVEL_IN, HID_REPORT_TYPE_INPUT };

/*********************************************************************
 * Profile Attributes - Table
 */

static gattAttribute_t battAttrTbl[] =
{
  // Battery Service
  {
    { ATT_BT_UUID_SIZE, primaryServiceUUID }, /* type */
    GATT_PERMIT_READ,                         /* permissions */
    0,                                        /* handle */
    (uint8 *)&battService                     /* pValue */
  },

    // Battery Level Declaration
    {
      { ATT_BT_UUID_SIZE, characterUUID },
      GATT_PERMIT_READ,
      0,
      &battLevelProps
    },

      // Battery Level Value
      {
        { ATT_BT_UUID_SIZE, battLevelUUID },
        GATT_PERMIT_READ,
        0,
        &battLevel
      },

      // Battery Level Client Characteristic Configuration
      {
        { ATT_BT_UUID_SIZE, clientCharCfgUUID },
        GATT_PERMIT_READ | GATT_PERMIT_WRITE,
        0,
        (uint8 *)&battLevelClientCharCfg
      },

      // HID Report Reference characteristic descriptor, batter level input
      {
        { ATT_BT_UUID_SIZE, reportRefUUID },
        GATT_PERMIT_READ,
        0,
        hidReportRefBattLevel
      },
      
      // Characteristic Presentation format
      {
        { ATT_BT_UUID_SIZE, charFormatUUID },
        GATT_PERMIT_READ,
        0,
        (uint8 *)&battLevelPresentation
      },
};


/*********************************************************************
 * LOCAL FUNCTIONS
 */
static bStatus_t battReadAttrCB( uint16 connHandle, gattAttribute_t *pAttr,
                                 uint8 *pValue, uint8 *pLen, uint16 offset,
                                 uint8 maxLen, uint8 method );
static bStatus_t battWriteAttrCB( uint16 connHandle, gattAttribute_t *pAttr,
                                  uint8 *pValue, uint8 len, uint16 offset,
                                  uint8 method );

static void battNotifyCB( linkDBItem_t *pLinkItem );
static uint8 battMeasure( void );
static void battNotifyLevel( void );

/*********************************************************************
 * PROFILE CALLBACKS
 */
// Battery Service Callbacks
CONST gattServiceCBs_t battCBs =
{
  battReadAttrCB,  // Read callback function pointer
  battWriteAttrCB, // Write callback function pointer
  NULL             // Authorization callback function pointer
};

/*********************************************************************
 * PUBLIC FUNCTIONS
 */

/*********************************************************************
 * @fn      Batt_AddService
 *
 * @brief   Initializes the Battery Service by registering
 *          GATT attributes with the GATT server.
 *
 * @return  Success or Failure
 */
bStatus_t Batt_AddService( void )
{
  uint8 status;

  // Allocate Client Characteristic Configuration table
  battLevelClientCharCfg = (gattCharCfg_t *)osal_mem_alloc( sizeof ( gattCharCfg_t ) * 
                                                            linkDBNumConns );
  if ( battLevelClientCharCfg == NULL )
  {
    return ( bleMemAllocError );
  }
  
  // Initialize Client Characteristic Configuration attributes
  GATTServApp_InitCharCfg( INVALID_CONNHANDLE, battLevelClientCharCfg );

  // Register GATT attribute list and CBs with GATT Server App
  status = GATTServApp_RegisterService( battAttrTbl,
                                        GATT_NUM_ATTRS( battAttrTbl ),
                                        GATT_MAX_ENCRYPT_KEY_SIZE,
                                        &battCBs );

  return ( status );
}

/*********************************************************************
 * @fn      Batt_Register
 *
 * @brief   Register a callback function with the Battery Service.
 *
 * @param   pfnServiceCB - Callback function.
 *
 * @return  None.
 */
extern void Batt_Register( battServiceCB_t pfnServiceCB )
{
  battServiceCB = pfnServiceCB;
}

/*********************************************************************
 * @fn      Batt_SetParameter
 *
 * @brief   Set a Battery Service parameter.
 *
 * @param   param - Profile parameter ID
 * @param   len - length of data to right
 * @param   value - pointer to data to write.  This is dependent on
 *          the parameter ID and WILL be cast to the appropriate
 *          data type (example: data type of uint16 will be cast to
 *          uint16 pointer).
 *
 * @return  bStatus_t
 */
bStatus_t Batt_SetParameter( uint8 param, uint8 len, void *value )
{
  bStatus_t ret = SUCCESS;

  switch ( param )
  {
    case BATT_PARAM_CRITICAL_LEVEL:
      battCriticalLevel = *((uint8*)value);

      // If below the critical level and critical state not set, notify it
      if ( battLevel < battCriticalLevel )
      {
        battNotifyLevel();
      }
      break;

    default:
      ret = INVALIDPARAMETER;
      break;
  }

  return ( ret );
}

/*********************************************************************
 * @fn      Batt_GetParameter
 *
 * @brief   Get a Battery Service parameter.
 *
 * @param   param - Profile parameter ID
 * @param   value - pointer to data to get.  This is dependent on
 *          the parameter ID and WILL be cast to the appropriate
 *          data type (example: data type of uint16 will be cast to
 *          uint16 pointer).
 *
 * @return  bStatus_t
 */
bStatus_t Batt_GetParameter( uint8 param, void *value )
{
  bStatus_t ret = SUCCESS;
  switch ( param )
  {
    case BATT_PARAM_LEVEL:
      *((uint8*)value) = battLevel;
      break;

    case BATT_PARAM_CRITICAL_LEVEL:
      *((uint8*)value) = battCriticalLevel;
      break;

    case BATT_PARAM_SERVICE_HANDLE:
      *((uint16*)value) = GATT_SERVICE_HANDLE( battAttrTbl );
      break;

    case BATT_PARAM_BATT_LEVEL_IN_REPORT:
      {
        hidRptMap_t *pRpt = (hidRptMap_t *)value;

        pRpt->id = hidReportRefBattLevel[0];
        pRpt->type = hidReportRefBattLevel[1];
        pRpt->handle = battAttrTbl[BATT_LEVEL_VALUE_IDX].handle;
        pRpt->pCccdAttr = &battAttrTbl[BATT_LEVEL_VALUE_CCCD_IDX];
        pRpt->mode = HID_PROTOCOL_MODE_REPORT;
      }
      break;

    default:
      ret = INVALIDPARAMETER;
      break;
  }

  return ( ret );
}

/*********************************************************************
 * @fn          Batt_MeasLevel
 *
 * @brief       Measure the battery level and update the battery
 *              level value in the service characteristics.  If
 *              the battery level-state characteristic is configured
 *              for notification and the battery level has changed
 *              since the last measurement, then a notification
 *              will be sent.
 *
 * @return      Success
 */
bStatus_t Batt_MeasLevel( void )
{
  uint8 level;

  level = battMeasure();

  // If level has gone down
  if (level<battLevel)
  {
    // Update level
    battLevel = level;

    // Send a notification
    battNotifyLevel();
  }

  return SUCCESS;
}

/*********************************************************************
 * @fn      Batt_Setup
 *
 * @brief   Set up which ADC source is to be used. Defaults to VDD/3.
 *
 * @param   adc_ch - ADC Channel, e.g. HAL_ADC_CHN_AIN6
 * @param   minVal - max battery level
 * @param   maxVal - min battery level
 * @param   sCB - HW setup callback
 * @param   tCB - HW tear down callback
 * @param   cCB - percentage calculation callback
 *
 * @return  none.
 */
void Batt_Setup( uint8 adc_ch, uint16 minVal, uint16 maxVal,
                 battServiceSetupCB_t sCB, battServiceTeardownCB_t tCB,
                 battServiceCalcCB_t cCB )
{
  battServiceAdcCh = adc_ch;
  battMinLevel = minVal;
  battMaxLevel = maxVal;

  battServiceSetupCB = sCB;
  battServiceTeardownCB = tCB;
  battServiceCalcCB = cCB;
}

/*********************************************************************
 * @fn          battReadAttrCB
 *
 * @brief       Read an attribute.
 *
 * @param       connHandle - connection message was received on
 * @param       pAttr - pointer to attribute
 * @param       pValue - pointer to data to be read
 * @param       pLen - length of data to be read
 * @param       offset - offset of the first octet to be read
 * @param       method - type of read message 
 *
 * @return      SUCCESS, blePending or Failure
 */
static bStatus_t battReadAttrCB( uint16 connHandle, gattAttribute_t *pAttr,
                                 uint8 *pValue, uint8 *pLen, uint16 offset,
                                 uint8 maxLen, uint8 method )
{
  bStatus_t status = SUCCESS;

  // Make sure it's not a blob operation (no attributes in the profile are long)
  if ( offset > 0 )
  {
    return ( ATT_ERR_ATTR_NOT_LONG );
  }

  uint16 uuid = BUILD_UINT16( pAttr->type.uuid[0], pAttr->type.uuid[1] );

  // Measure battery level if reading level
  if ( uuid == BATT_LEVEL_UUID )
  {
    uint8 level;

    level = battMeasure();

    // If level has gone down
    if (level<battLevel)
    {
      // Update level
      battLevel = level;
    }

    *pLen = 1;
    pValue[0] = battLevel;
  }
  else if ( uuid == GATT_REPORT_REF_UUID )
  {
    *pLen = HID_REPORT_REF_LEN;
    osal_memcpy( pValue, pAttr->pValue, HID_REPORT_REF_LEN );
  }
  else
  {
    status = ATT_ERR_ATTR_NOT_FOUND;
  }

  return ( status );
}

/*********************************************************************
 * @fn      battWriteAttrCB
 *
 * @brief   Validate attribute data prior to a write operation
 *
 * @param   connHandle - connection message was received on
 * @param   pAttr - pointer to attribute
 * @param   pValue - pointer to data to be written
 * @param   len - length of data
 * @param   offset - offset of the first octet to be written
 * @param   method - type of write message 
 *
 * @return  SUCCESS, blePending or Failure
 */
static bStatus_t battWriteAttrCB( uint16 connHandle, gattAttribute_t *pAttr,
                                  uint8 *pValue, uint8 len, uint16 offset,
                                  uint8 method )
{
  bStatus_t status = SUCCESS;

  uint16 uuid = BUILD_UINT16( pAttr->type.uuid[0], pAttr->type.uuid[1]);
  switch ( uuid )
  {
    case GATT_CLIENT_CHAR_CFG_UUID:
      status = GATTServApp_ProcessCCCWriteReq( connHandle, pAttr, pValue, len,
                                               offset, GATT_CLIENT_CFG_NOTIFY );
      if ( status == SUCCESS )
      {
        uint16 charCfg = BUILD_UINT16( pValue[0], pValue[1] );

        if ( battServiceCB )
        {
          (*battServiceCB)( (charCfg == GATT_CFG_NO_OPERATION) ?
                            BATT_LEVEL_NOTI_DISABLED :
                            BATT_LEVEL_NOTI_ENABLED);
        }
      }
      break;

    default:
      status = ATT_ERR_ATTR_NOT_FOUND;
      break;
  }

  return ( status );
}

/*********************************************************************
 * @fn          battNotifyCB
 *
 * @brief       Send a notification of the level state characteristic.
 *
 * @param       connHandle - linkDB item
 *
 * @return      None.
 */
static void battNotifyCB( linkDBItem_t *pLinkItem )
{
  if ( pLinkItem->stateFlags & LINK_CONNECTED )
  {
    uint16 value = GATTServApp_ReadCharCfg( pLinkItem->connectionHandle,
                                            battLevelClientCharCfg );
    if ( value & GATT_CLIENT_CFG_NOTIFY )
    {
      attHandleValueNoti_t noti;
          
      noti.pValue = GATT_bm_alloc( pLinkItem->connectionHandle,
                                   ATT_HANDLE_VALUE_NOTI, 
                                   BATT_LEVEL_VALUE_LEN, NULL );
      if ( noti.pValue != NULL )
      {
        noti.handle = battAttrTbl[BATT_LEVEL_VALUE_IDX].handle;
        noti.len = BATT_LEVEL_VALUE_LEN;
        noti.pValue[0] = battLevel;

        if ( GATT_Notification( pLinkItem->connectionHandle, &noti, FALSE ) != SUCCESS )
        {
          GATT_bm_free( (gattMsg_t *)&noti, ATT_HANDLE_VALUE_NOTI );
        }
      }
    }
  }
}

/*********************************************************************
 * @fn      battMeasure
 *
 * @brief   Measure the battery level with the ADC and return
 *          it as a percentage 0-100%.
 *
 * @return  Battery level.
 */
static uint8 battMeasure( void )
{
  uint16 adc = 0;
  uint8 percent;

  /**
   * Battery level conversion from ADC to a percentage:
   *
   * The maximum ADC value for the battery voltage level is 511 for a
   * 10-bit conversion.  The ADC value is references vs. 1.25v and
   * this maximum value corresponds to a voltage of 3.75v.
   *
   * For a coin cell battery 3.0v = 100%.  The minimum operating
   * voltage of the CC2540 is 2.0v so 2.0v = 0%.
   *
   * To convert a voltage to an ADC value use:
   *
   *   (v/3)/1.25 * 511 = adc
   *
   * 3.0v = 409 ADC
   * 2.0v = 273 ADC
   *
   * We need to map ADC values from 409-273 to 100%-0%.
   *
   * Normalize the ADC values to zero:
   *
   * 409 - 273 = 136
   *
   * And convert ADC range to percentage range:
   *
   * percent/adc = 100/136 = 25/34
   *
   * Resulting in the final equation, with round:
   *
   * percent = ((adc - 273) * 25) + 33 / 34
   */
   adc = 1.15*889/2047;
   percent = ((adc - 1250) * 10) + 33 / 35;
  // Call measurement setup callback
  if (battServiceSetupCB != NULL)
  {
    battServiceSetupCB();
  }

  // Configure ADC and perform a read
  HalAdcSetReference( HAL_ADC_REF_AIN7 );
  adc = HalAdcRead( battServiceAdcCh, HAL_ADC_RESOLUTION_12);

  // Call measurement teardown callback
  if (battServiceTeardownCB != NULL)
  {
    battServiceTeardownCB();
  }

  if (adc >= battMaxLevel)
  {
    percent = 100;
  }
  else if (adc <= battMinLevel)
  {
    percent = 0;
  }
  else
  {
    if (battServiceCalcCB != NULL)
    {
      percent = battServiceCalcCB(adc);
    }
    else
    {
      uint16 range =  battMaxLevel - battMinLevel + 1;

      // optional if you want to keep it even, otherwise just take floor of divide
      // range += (range & 1);
      range >>= 2; // divide by 4

      percent = (uint8) ((((adc - battMinLevel) * 25) + (range - 1)) / range);
    }
  }

  return percent;
}

/*********************************************************************
 * @fn      battNotifyLevelState
 *
 * @brief   Send a notification of the battery level state
 *          characteristic if a connection is established.
 *
 * @return  None.
 */
static void battNotifyLevel( void )
{
  // Execute linkDB callback to send notification
  linkDB_PerformFunc( battNotifyCB );
}


/*********************************************************************
*********************************************************************/