AMiRo-OS

#include <ch.hpp>

#include <hal.h>

#include <chdebug.h>

#include <chprintf.h>

#include <amiro/bus/i2c/I2CParams.hpp>

#include <amiro/bus/i2c/I2CDriver.hpp>

#include <amiro/proximity/vcnl4020.hpp>

using namespace chibios_rt;

namespace amiro {

VCNL4020::

~VCNL4020() {

}

VCNL4020::

VCNL4020(I2CDriver *driver, const VCNL4020Config *config) :

  BaseStaticThread<256>(),

  driver(driver),

  config(config),

  ambient(0x0000u),

  proximity(0x0000u),

  proximityOffset(0x0000u) {

  this->tx_params.addr = VCNL4020::SLA;

}

uint16_t

VCNL4020::

getAmbientLight() {

  return this->ambient;

}

void

VCNL4020::

setProximityOffset(uint16_t offset) {

  this->proximityOffset = offset;

}

uint16_t

VCNL4020::

getProximityOffset() {

  return this->proximityOffset;

}

EvtSource*

VCNL4020::

getEventSource() {

  return &this->eventSource;

}

uint16_t

VCNL4020::

getProximity() {

  return this->proximity;

}

uint16_t

VCNL4020::

getProximityScaledWoOffset() {

  if (this->proximity <= this->proximityOffset)

    return 0;

  // Scale factor for the offset-less proximity value, so that we can reach full-scale

  const float scaleFactor = float(0xFFFFu) / float((0xFFFFu - this->proximityOffset));

  return uint16_t(float(this->proximity - this->proximityOffset) * scaleFactor);

}

msg_t

VCNL4020::

main(void) {

  I2CDriver *drv = this->driver;

  msg_t res;

  this->setName("Vcnl4020");

  drv->acquireBus();

  /* exit if writing configuration fails */

  res = this->writeIRConf();

  drv->releaseBus();

  if (res)

    return RDY_RESET;

  //TODO Read calibration from eeprom

  while (!this->shouldTerminate()) {

    drv->acquireBus();

    this->readIntensities();

    drv->releaseBus();

    this->eventSource.broadcastFlags(0);

    this->waitAnyEventTimeout(ALL_EVENTS, MS2ST(200));

  }

  return RDY_OK;

}

msg_t

VCNL4020::

writeIRConf() {

  msg_t res;

  const VCNL4020Config *cfg = this->config;

  uint8_t buffer[4];

  this->tx_params.txbuf = buffer;

  this->tx_params.txbytes = 4;

  this->tx_params.rxbytes = 0;

  buffer[0] = offsetof(VCNL4020::registers, proximity_rate);

  buffer[1] = cfg->proximity_rate;

  buffer[2] = cfg->ir_led_current_mA > 200 ? 20u : cfg->ir_led_current_mA / 10u;

  buffer[3] = cfg->ambient_parameter;

  res = this->driver->masterTransmit(&this->tx_params);

  buffer[0] = offsetof(VCNL4020::registers, command);

  buffer[1] = cfg->command;

  this->tx_params.txbytes = 2;

  if (!res)

    res = this->driver->masterTransmit(&this->tx_params);

  return res;

}

msg_t

VCNL4020::

readIntensities() {

  msg_t res;

  uint8_t buffer[4];

  uint8_t reg = offsetof(VCNL4020::registers, ambient_result);

  this->tx_params.txbuf = ®

  this->tx_params.txbytes = 1;

  this->tx_params.rxbuf = buffer;

  this->tx_params.rxbytes = 4;

  res = this->driver->masterTransmit(&this->tx_params);

  if (!res) {

    /* update internal values */

    this->ambient = (buffer[0] << 8) | buffer[1];

    this->proximity = (buffer[2] << 8) | buffer[3];

  }

  return res;

}

uint8_t

VCNL4020::

getCheck(void) {

  int8_t resTx;

  uint8_t rxBuffer[2]; /** This is a bug workaround: 1 byte is impossible to read on STM32F1*/

  const uint8_t txBuffer = uint8_t(offsetof(VCNL4020::registers, revision));

  // Use own datastructure, so that there is now faulty

  // behaviour with the other threads using it

  I2CTxParams tx_params = this->tx_params;

  tx_params.txbuf = &txBuffer;

  tx_params.txbytes = 1;

  tx_params.rxbytes = 2; /** This is a bug workaround: 1 byte is impossible to read on STM32F1*/

  tx_params.rxbuf = rxBuffer;

  // Read the data

  resTx = this->driver->masterTransmit(&tx_params);

  // Failed to transmit

  if (resTx != RDY_OK || VCNL4020::PRODUCT_ID_REVISION != rxBuffer[0]) {

    return VCNL4020::CHECK_FAIL;

  } else {

    return VCNL4020::CHECK_OK;

  }

}

uint8_t

VCNL4020::

calibrate() {

  uint16_t proximityFloorMeanValue;

  // Get the offset

  msg_t res = calibrateOffset(proximityFloorMeanValue);

  if (res == CALIB_OK) {

    this->proximityOffset = proximityFloorMeanValue;

    //TODO Write value to eeprom

    return res;

  } else {

    return res;

  }

}

uint8_t

VCNL4020::

calibrateOffset(uint16_t &proximityFloorMeanValue) {

  uint32_t tmpProximityFloorMeanValue;

  // Register an event listener, to receive updates

  chibios_rt::EvtListener eventTimerEvtListener;

  chibios_rt::EvtSource *vcnlEvtSource;

  vcnlEvtSource = reinterpret_cast<EvtSource *>(this->getEventSource());

  vcnlEvtSource->registerOne(&eventTimerEvtListener,0);

  // Get the first values

  tmpProximityFloorMeanValue = this->getProximity();

  // Get the others with a floating mean

  const uint32_t maxValues = 20;

  for (uint32_t idxMean = 2; idxMean <= maxValues; ++idxMean) {

    this->waitOneEvent(ALL_EVENTS); /* Wait for a new update */

    tmpProximityFloorMeanValue = (((idxMean-1) * tmpProximityFloorMeanValue) + uint32_t(this->getProximity())) / idxMean;

  }

  vcnlEvtSource->unregister(&eventTimerEvtListener);

  // Cast the calculated offset to the temporary member variable

  proximityFloorMeanValue = uint16_t(tmpProximityFloorMeanValue);

  return CALIB_OK;

}

} /* amiro */