upm: enable LIDAR-Lite V3 Optical Distance Measurement sensor library

and example

LIDAR-Lite v3, a compact, high-performance optical distance measurement
sensor from Garmin™. It is the ideal solution for drone, robot or unmanned
vehicle applications.

The library provided is libupm-lidarlitev3.so
The example provided is lidarlitev3.cxx where it will print the distance
of object/obstacle from the sensor.

The image of the sensor is at docs/images/lidarlitev3.jpg

Signed-off-by: Saloni Jain <saloni.jain@tcs.com>
Signed-off-by: Niti Rohilla <niti.rohilla@tcs.com>
Signed-off-by: Abhishek Malik <abhishek.malik@intel.com>

src/lidarlitev3/lidarlitev3.cxx

@@ -0,0 +1,139 @@
+/*
+ * Author: Saloni Jain <saloni.jain@tcs.com>
+ * Author: Niti Rohilla <niti.rohilla@tcs.com>
+ * Copyright (c) 2014 Intel Corporation.
+ *
+ * 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.
+ */
+
+#include <iostream>
+#include <string>
+#include <stdexcept>
+#include <unistd.h>
+#include <stdlib.h>
+
+#include "lidarlitev3.hpp"
+
+using namespace upm;
+
+LIDARLITEV3::LIDARLITEV3 (int bus, int devAddr) : m_i2ControlCtx(bus) {
+    m_name = "LIDARLITEV3";
+
+    m_controlAddr = devAddr;
+    m_bus = bus;
+
+    mraa::Result ret = m_i2ControlCtx.address(m_controlAddr);
+    if (ret != mraa::SUCCESS) {
+        throw std::invalid_argument(std::string(__FUNCTION__) +
+                                    ": mraa_i2c_address() failed");
+    }
+}
+
+int
+LIDARLITEV3::getDistance () {
+
+    if(i2cWriteReg(ACQ_COMMAND, 0x04) < 0)
+        return -1;
+
+    return read(0x8f,true);
+}
+
+uint16_t
+LIDARLITEV3::read(int reg, bool monitorBusyFlag) {
+    int busyFlag = 0; // busyFlag monitors when the device is done with a measurement
+    int busyCounter = 0; // busyCounter counts number of times busy flag is checked, for timeout
+    uint8_t data;
+    uint16_t distance;
+
+    if(monitorBusyFlag) {
+        busyFlag = 1; // Begin read immediately if not monitoring busy flag
+    }
+
+    while(busyFlag != 0) { // Loop until device is not busy
+        // Read status register to check busy flag
+        data = i2cReadReg_8 (0x01); // Read register 0x01
+        busyFlag = data & 1; // Assign the LSB of the status register to busyFlag
+
+        busyCounter++; // Increment busyCounter for timeout
+
+        // Handle timeout condition, exit while loop and goto bailout
+        if(busyCounter > 9999) {
+            goto timeout;
+        }
+    }
+
+    if (busyFlag == 0) {
+        // Read bytes to obtain 16-bit measured distance in centimeters
+        distance = i2cReadReg_16(0x8f);
+    }
+
+    // timeout reports error
+    if(busyCounter > 9999) {
+        timeout:
+        busyCounter = 0;
+        throw std::invalid_argument(std::string(__FUNCTION__) +
+                                    ": Read timeout");
+    }
+    return distance;
+}
+
+uint16_t
+LIDARLITEV3::i2cReadReg_16 (int reg) {
+    uint16_t data;
+
+    m_i2ControlCtx.address(m_controlAddr);
+    m_i2ControlCtx.writeByte(reg);
+
+    m_i2ControlCtx.address(m_controlAddr);
+    m_i2ControlCtx.read((uint8_t *)&data, 0x2);
+
+    uint8_t high = (data & 0xFF00) >> 8;
+    data = (data << 8) & 0xFF00;
+    data |= high;
+
+    return data;
+}
+
+uint8_t
+LIDARLITEV3::i2cReadReg_8 (int reg) {
+    uint8_t data;
+
+    m_i2ControlCtx.address(m_controlAddr);
+    m_i2ControlCtx.writeByte(reg);
+
+    m_i2ControlCtx.address(m_controlAddr);
+    m_i2ControlCtx.read(&data, 0x1);
+
+    return data;
+}
+
+mraa::Result
+LIDARLITEV3::i2cWriteReg (uint8_t reg, uint8_t value) {
+    mraa::Result error = mraa::SUCCESS;
+
+    uint8_t data[2] = { reg, value };
+    error = m_i2ControlCtx.address (m_controlAddr);
+    error = m_i2ControlCtx.write (data, 2);
+    if ( error != mraa::SUCCESS)
+      throw std::invalid_argument(std::string(__FUNCTION__) +
+                                  ": mraa_i2c_write() failed");
+
+    return error;
+}