/*
   Copyright (c) 2014-2016 by Plexim GmbH
   All rights reserved.

   A free license is granted to anyone to use this software for any legal
   non safety-critical purpose, including commercial applications, provided
   that:
   1) IT IS NOT USED TO DIRECTLY OR INDIRECTLY COMPETE WITH PLEXIM, and
   2) THIS COPYRIGHT NOTICE IS PRESERVED in its entirety.

   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.
 */

#include "plx_ain.h"

#pragma diag_suppress 112  // ASSERT(0) in switch statements

#define PLX_AIN_ADC_msDELAY 10L

static void PLX_AIN_powerupAdc(PLX_AIN_Handle_t aHandle,
                               const PLX_AIN_AdcParams_t *aParams);

static uint32_t PLX_AIN_DelayCountsPerMs;

void DSP28x_usDelay(long LoopCount);

void PLX_AIN_sinit(uint32_t aSysClkHz) {
  AdcRegs.ADCTRL2.bit.RST_SEQ1 = 1;    // Reset SEQ1
  AdcRegs.ADCST.bit.INT_SEQ1_CLR = 1;  // Clear INT SEQ1 bit
  PLX_AIN_DelayCountsPerMs =
      (uint32_t)(((float)aSysClkHz / 1000.0 - 0.9) / 5.0);
}

void PLX_AIN_setDefaultAdcParams(PLX_AIN_AdcParams_t *aParams,
                                 bool useExternalVref, float aVref,
                                 bool sigmodeDifferential) {
  aParams->ADCTRL1.bit.SEQ_CASC = 1;   // cascaded sequence mode
  aParams->ADCTRL3.bit.SMODE_SEL = 0;  // no simultaneous sampling
  aParams->ADCTRL2.bit.INT_ENA_SEQ1 = 1;
  aParams->ADCTRL2.bit.INT_MOD_SEQ1 = 0;
  aParams->ADCTRL1.bit.CPS = 1;       // clock prescaler 1/2
  aParams->ADCTRL1.bit.SEQ_OVRD = 0;  // disable sequencer override
  aParams->ADCTRL2.bit.EPWM_SOCA_SEQ1 = 0;

  // copy over voltage Reference configuration info
  aParams->useExternalVref = useExternalVref;
  aParams->vref = aVref;

  // configure voltage reference hardware
  if (useExternalVref) {
    PLX_ASSERT(0);  // external reference not supported
  } else {          // using the internal reference
    PLX_ASSERT(aVref == 3.0f);
    aParams->ADCREFSEL.bit.REF_SEL = 0;  // Select internal BG
  }
}

PLX_AIN_Handle_t PLX_AIN_init(void *aMemory, const size_t aNumBytes) {
  PLX_AIN_Handle_t handle;

  if (aNumBytes < sizeof(PLX_AIN_Obj_t)) {
    return ((PLX_AIN_Handle_t)NULL);
  }

  // set handle
  handle = (PLX_AIN_Handle_t)aMemory;

  return handle;
}

void PLX_AIN_configure(PLX_AIN_Handle_t aHandle, PLX_AIN_Unit_t aUnit,
                       const PLX_AIN_AdcParams_t *aParams) {
  PLX_AIN_Obj_t *obj = (PLX_AIN_Obj_t *)aHandle;

  // copy over voltage Reference configuration info
  obj->voltsPerAdcBit = aParams->vref / 4096.0f;

  PLX_ASSERT(aUnit == PLX_AIN_ADC);  // This target has only one ADC unit

  obj->adc = &AdcRegs;

  EALLOW;
  SysCtrlRegs.PCLKCR0.bit.ADCENCLK = 1;
  EDIS;

  PLX_AIN_powerupAdc(aHandle, aParams);

  EALLOW;
  obj->adc->ADCTRL1.bit.SEQ_OVRD = aParams->ADCTRL1.bit.SEQ_OVRD;
  obj->adc->ADCTRL1.bit.ACQ_PS = aParams->ADCTRL1.bit.ACQ_PS;

  obj->adc->ADCTRL2.bit.INT_ENA_SEQ1 = aParams->ADCTRL2.bit.INT_ENA_SEQ1;
  obj->adc->ADCTRL2.bit.INT_MOD_SEQ1 = aParams->ADCTRL2.bit.INT_MOD_SEQ1;
  // cascaded sequence mode
  obj->adc->ADCTRL1.bit.SEQ_CASC = aParams->ADCTRL1.bit.SEQ_CASC;
  // no simultaneous sampling
  obj->adc->ADCTRL3.bit.SMODE_SEL = aParams->ADCTRL3.bit.SMODE_SEL;
  EDIS;

  PLX_AIN_resetChannelSetup(aHandle);
}

void PLX_AIN_setDefaultChannelParams(PLX_AIN_ChannelParams_t *aParams) {
  aParams->trigsel = 0;
  aParams->scale = 1.0;
  aParams->offset = 0.0;
}

void PLX_AIN_resetChannelSetup(PLX_AIN_Handle_t aHandle) {
  PLX_AIN_Obj_t *obj = (PLX_AIN_Obj_t *)aHandle;

  EALLOW;
  obj->adc->ADCTRL3.bit.SMODE_SEL = 0;  // no simultaneous sampling
  EDIS;
}

void PLX_AIN_setupChannel(PLX_AIN_Handle_t aHandle, uint16_t aChannel,
                          uint16_t aSource,
                          const PLX_AIN_ChannelParams_t *aParams) {
  PLX_AIN_Obj_t *obj = (PLX_AIN_Obj_t *)aHandle;

  PLX_ASSERT(aChannel < PLX_AIN_NUM_CHANNELS);

  EALLOW;
  // TRIGSEL is not a feature of this chip, but we are using the convention of
  // newer MCUs
  if (aParams->trigsel >= 5) {
    obj->adc->ADCTRL2.bit.EPWM_SOCA_SEQ1 = 1;  // Enable SOCA from ePWM
                                               // to start SEQ1
  }

  // This code assumes channels are asigned in rising order,
  // which they are, so last assignment = numChannels
  obj->adc->ADCMAXCONV.all = aChannel;

  switch (aChannel) {
    case 0:
      obj->adc->ADCCHSELSEQ1.bit.CONV00 = aSource;
      break;
    case 1:
      obj->adc->ADCCHSELSEQ1.bit.CONV01 = aSource;
      break;
    case 2:
      obj->adc->ADCCHSELSEQ1.bit.CONV02 = aSource;
      break;
    case 3:
      obj->adc->ADCCHSELSEQ1.bit.CONV03 = aSource;
      break;
    case 4:
      obj->adc->ADCCHSELSEQ2.bit.CONV04 = aSource;
      break;
    case 5:
      obj->adc->ADCCHSELSEQ2.bit.CONV05 = aSource;
      break;
    case 6:
      obj->adc->ADCCHSELSEQ2.bit.CONV06 = aSource;
      break;
    case 7:
      obj->adc->ADCCHSELSEQ2.bit.CONV07 = aSource;
      break;
    case 8:
      obj->adc->ADCCHSELSEQ3.bit.CONV08 = aSource;
      break;
    case 9:
      obj->adc->ADCCHSELSEQ3.bit.CONV09 = aSource;
      break;
    case 10:
      obj->adc->ADCCHSELSEQ3.bit.CONV10 = aSource;
      break;
    case 11:
      obj->adc->ADCCHSELSEQ3.bit.CONV11 = aSource;
      break;
    case 12:
      obj->adc->ADCCHSELSEQ4.bit.CONV12 = aSource;
      break;
    case 13:
      obj->adc->ADCCHSELSEQ4.bit.CONV13 = aSource;
      break;
    case 14:
      obj->adc->ADCCHSELSEQ4.bit.CONV14 = aSource;
      break;
    case 15:
      obj->adc->ADCCHSELSEQ4.bit.CONV15 = aSource;
      break;
    default:
      break;
  }
  EDIS;
  obj->scale[aChannel] = aParams->scale * obj->voltsPerAdcBit;
  obj->offset[aChannel] = aParams->offset;
}

static void PLX_AIN_powerupAdc(PLX_AIN_Handle_t aHandle,
                               const PLX_AIN_AdcParams_t *aParams) {
  PLX_AIN_Obj_t *obj = (PLX_AIN_Obj_t *)aHandle;

  EALLOW;
  obj->adc->ADCTRL1.bit.RESET = 1;  // Reset ADC
  asm(" NOP ");
  asm(" NOP ");  // need two clock cycles after reset before doing anything with
                 // the ADC
  EDIS;

  // To powerup the ADC the ADCENCLK bit should be set first to enable
  // clocks, followed by powering up the bandgap, reference circuitry, and ADC
  // core. Before the first conversion is performed a 5ms delay must be observed
  // after power up to give all analog circuits time to power up and settle

  // Please note that for the delay function below to operate correctly the
  // CPU_RATE define statement in the F2806x_Examples.h file must
  // contain the correct CPU clock period in nanoseconds.

  if (aParams->useExternalVref) {
    // separate power up sequence for External Reference
    PLX_ASSERT(0);  // not configured for external references yet!!

  } else {  // use the internal reference,
    // must power up BG before selecting the Internal Reference
    EALLOW;
    obj->adc->ADCTRL3.bit.ADCBGRFDN = 3;  // Power ADC BG
    obj->adc->ADCTRL3.bit.ADCPWDN = 1;    // Power ADC
    obj->adc->ADCREFSEL.bit.REF_SEL =
        aParams->ADCREFSEL.bit.REF_SEL;  // Select internal BG
    EDIS;
  }

  // Delay before converting ADC channels
  DSP28x_usDelay(PLX_AIN_ADC_msDELAY * PLX_AIN_DelayCountsPerMs);

  EALLOW;
  obj->adc->ADCTRL1.bit.CPS = aParams->ADCTRL1.bit.CPS;
  EDIS;

  // Call to adc calibration routine stored in OTP by TI
  EALLOW;
#define ADC_Cal (void (*)(void))0x380080
  (*ADC_Cal)();
  EDIS;

// Delay before converting ADC channels
  DSP28x_usDelay(PLX_AIN_ADC_msDELAY * PLX_AIN_DelayCountsPerMs);
}
