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/* Copyright (c) 2010-2011 mbed.org, MIT License
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this software
* and associated documentation files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all copies or
* substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
* BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

/* Driver extended by Mac Lobdell */
/* Added tap detection, orientation, and data ready interrupt capability */
/* Added capability to check interrupt source, tap type, and orientation */
/* See MMA8451Q.h for configuration to enable/disable different features */
/* Several bits and pieces taken from MMA8452Q basic example code by Nathan Seidle at SparkFun under Beerware license */
 
#include "MMA8451Q.h"

#define REG_WHO_AM_I      0x0D
#define REG_CTRL_REG_1    0x2A
#define REG_OUT_X_MSB     0x01
#define REG_OUT_Y_MSB     0x03
#define REG_OUT_Z_MSB     0x05

#define UINT14_MAX        16383

// Set the scale below either 2, 4 or 8
#define SCALE  2;  // Sets full-scale range to +/-2, 4, or 8g. Used to calc real g values.
// Set the output data rate below. Value should be between 0 and 7
#define DATARATE = 0;  // 0=800Hz, 1=400, 2=200, 3=100, 4=50, 5=12.5, 6=6.25, 7=1.56

extern Serial pc;

MMA8451Q::MMA8451Q(PinName sda, PinName scl, int addr) : m_i2c(sda, scl), m_addr(addr)
{
  //To-do: need to clear registers before writing because they only get cleared on a power cycle
  
   modeStandby();  // Must be in standby to change registers     

/*    pc.printf("++++++++++++++++++\n\r");
    uint8_t myRegs = 0;  
    for(uint8_t i = 0; i<0x31;i++)
    {
      myRegs = readRegister(i);
      pc.printf("%x: %x\n\r",i,myRegs);   
    }
    pc.printf("+==+==+==++===+=+\n\r");
*/
  
  // Set up the full scale range to 2, 4, or 8g.
  //if ((fsr==2)||(fsr==4)||(fsr==8))
    writeRegister(0x0E, 0);  //SCALE >> 2);      
  //else
  //  writeRegister(0x0E, 0);

  // Setup the 3 data rate bits, from 0 to 7
  writeRegister(0x2A, readRegister(0x2A) & ~(0x38));
  //if (DATARATE <= 7)
  // writeRegister(0x2A, readRegister(0x2A) | (DATARATE << 3));  

  // Set up portrait/landscap registers - 4 steps:
  // 1. Enable P/L
  // 2. Set the back/front angle trigger points (z-lock)
  // 3. Set the threshold/hysteresis angle
  // 4. Set the debouce rate
  // For more info check out this app note: http://cache.freescale.com/files/sensors/doc/app_note/AN4068.pdf
if(MMA8451Q_ENABLE_ORIENTATION)
{
pc.printf("setting orientation configuraiton \n\r");

  writeRegister(0x11, 0x40);  // 1. Enable P/L
  writeRegister(0x13, 0x44);  // 2. 29deg z-lock (don't think this register is actually writable)
  writeRegister(0x14, 0x84);  // 3. 45deg thresh, 14deg hyst (don't think this register is writable either)
  writeRegister(0x12, 0x50);  // 4. debounce counter at 100ms (at 800 hz)
}

  /* Set up single and double tap - 5 steps:
   1. Set up single and/or double tap detection on each axis individually.
   2. Set the threshold - minimum required acceleration to cause a tap.
   3. Set the time limit - the maximum time that a tap can be above the threshold
   4. Set the pulse latency - the minimum required time between one pulse and the next
   5. Set the second pulse window - maximum allowed time between end of latency and start of second pulse
   for more info check out this app note: http://cache.freescale.com/files/sensors/doc/app_note/AN4072.pdf */
if(  MMA8451Q_ENABLE_DOUBLE_Z_TAP | MMA8451Q_ENABLE_SINGLE_Z_TAP)
{
  //writeRegister(0x21, 0x7F);  // 1. enable single/double taps on all axes
  // writeRegister(0x21, 0x55);  // 1. single taps only on all axes
  // writeRegister(0x21, 0x6A);  // 1. double taps only on all axes
 pc.printf("setting tap configuraiton \n\r");
 
 
 if(MMA8451Q_ENABLE_DOUBLE_Z_TAP)
     writeRegister(0x21, readRegister(0x21) | 0x60);  // 1. enable double taps on Z axes
 if(MMA8451Q_ENABLE_SINGLE_Z_TAP)
      writeRegister(0x21, readRegister(0x21) | 0x50);  // 1. enable single taps on Z axes
 
 
 /* set up the Tap threshold and timing */
 //not doing x,y taps
//  writeRegister(0x23, 0x20);  // 2. x thresh at 2g, multiply the value by 0.0625g/LSB to get the threshold
//  writeRegister(0x24, 0x20);  // 2. y thresh at 2g, multiply the value by 0.0625g/LSB to get the threshold
//  writeRegister(0x25, 0x08);  // 2. z thresh at .5g, multiply the value by 0.0625g/LSB to get the threshold
  writeRegister(0x25, 0x04);  // 2. z thresh at ?g, multiply the value by 0.0625g/LSB to get the threshold  
  writeRegister(0x26, 0x30);  // 3. 30ms time limit at 800Hz odr, this is very dependent on data rate, see the app note
  writeRegister(0x27, 0xA0);  // 4. 200ms (at 800Hz odr) between taps min, this also depends on the data rate
  writeRegister(0x28, 0xFF);  // 5. 318ms (max value) between taps max
}

if(  MMA8451Q_ENABLE_DOUBLE_Z_TAP | MMA8451Q_ENABLE_SINGLE_Z_TAP | MMA8451Q_ENABLE_DATAREADY | MMA8451Q_ENABLE_ORIENTATION)
{
  pc.printf("setting up interrupts \n\r");

  // Set up interrupt 1 and 2
  
  // writeRegister(0x2C, 0x02);  // Active high, push-pull interrupts
   writeRegister(0x2C, 0x01);  // Active low, push-pull interrupts
  
  //writeRegister(0x2D, 0x19);  // DRDY, P/L and tap ints enabled
//  writeRegister(0x2D, 0x9);  // DRDY, tap ints enabled

if(  MMA8451Q_ENABLE_DATAREADY)
{//enable data ready interrupts
   writeRegister(0x2D, readRegister(0x2D)| 0x1);  // DRDY ints enabled
}  
if(  MMA8451Q_ENABLE_DOUBLE_Z_TAP | MMA8451Q_ENABLE_SINGLE_Z_TAP)
{//enable tap interrupts
   writeRegister(0x2D, readRegister(0x2D)| 0x8);  // taps ints enabled
}
if(  MMA8451Q_ENABLE_ORIENTATION)
{//enable orientation interrupts
   writeRegister(0x2D, readRegister(0x2D)| 0x10);  // orientation ints enabled
}

  writeRegister(0x2E, 0x01);  // DRDY on INT1, P/L and taps on INT2
  
}

  modeActive();  // Set to active to start reading

/*
    pc.printf("Print Registers\n\r");
    pc.printf("---------------\n\r");
     myRegs = 0;  
    for(uint8_t i = 0; i<0x31;i++)
    {
      myRegs = readRegister(i);
      pc.printf("%x: %x\n\r",i,myRegs);   
    }
    pc.printf("================\n\r");
*/
     
}

MMA8451Q::~MMA8451Q() { }

uint8_t MMA8451Q::getWhoAmI()
{
    uint8_t who_am_i = 0;
    readRegs(REG_WHO_AM_I, &who_am_i, 1);
    return who_am_i;
}

float MMA8451Q::getAccX()
{
    return (float(getAccAxis(REG_OUT_X_MSB))/4096.0);
}

float MMA8451Q::getAccY()
{
    return (float(getAccAxis(REG_OUT_Y_MSB))/4096.0);
}

float MMA8451Q::getAccZ()
{
    return (float(getAccAxis(REG_OUT_Z_MSB))/4096.0);
}

void MMA8451Q::getAccAllAxis(float * res)
{
    res[0] = getAccX();
    res[1] = getAccY();
    res[2] = getAccZ();
}

int16_t MMA8451Q::getAccAxis(uint8_t addr)
{
    int16_t acc;
    uint8_t res[2];
    readRegs(addr, res, 2);

    acc = (res[0] << 6) | (res[1] >> 2);
    if (acc > UINT14_MAX/2)
        acc -= UINT14_MAX;

    return acc;
}

void MMA8451Q::readRegs(int addr, uint8_t * data, int len)
{
    char t[1] = {addr};
    m_i2c.write(m_addr, t, 1, true);
    m_i2c.read(m_addr, (char *)data, len);
}

void MMA8451Q::writeRegs(uint8_t * data, int len)
{
    m_i2c.write(m_addr, (char *)data, len);
}

void MMA8451Q::writeRegister(uint8_t reg, uint8_t data)
{  //write to single register
     uint8_t wdata[2] = {reg, data};
     m_i2c.write(m_addr, (char *)wdata, 2);
     
}
uint8_t MMA8451Q::readRegister(uint8_t reg)
{  //read single register

    uint8_t data;
    readRegs(reg, &data, 1);   
    
    return data; 
}

// Sets the MMA8452 to standby mode.
// It must be in standby to change most register settings
void MMA8451Q::modeStandby(void)
{
  uint8_t c = readRegister(0x2A);
  writeRegister(0x2A, c & ~(0x01));
}

// Sets the MMA8452 to active mode.
// Needs to be in this mode to output data
void MMA8451Q::modeActive(void)
{
 int8_t c = readRegister(0x2A);
  writeRegister(0x2A, c | 0x01);
}

uint8_t MMA8451Q::direction(void)
{
  uint8_t pl = readRegister(0x10);  // Reads the PL_STATUS register
  return pl;

}
uint8_t MMA8451Q::tapSource(void)
{
  uint8_t source = readRegister(0x22);  // Reads the PULSE_SRC register
  return source;
}
uint8_t MMA8451Q::intSource(void)
{
  uint8_t  source = readRegister(0x0C);  // Read the interrupt source reg.
  return source;
}