bh1750: Initial implementation

This driver was developed with the DFRobot Light Sensor based on the
BH1750.  It has a sensitivity of .5 to 65535 Lux.  It supports
voltages from 3-5vdc and is connected via I2C.

Signed-off-by: Jon Trulson <jtrulson@ics.com>

src/bh1750/bh1750.cxx

@@ -0,0 +1,99 @@
+/*
+ * Author: Jon Trulson <jtrulson@ics.com>
+ * Copyright (c) 2016 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 <stdexcept>
+
+#include "bh1750.hpp"
+
+using namespace upm;
+using namespace std;
+
+BH1750::BH1750(int bus, int addr, BH1750_OPMODES_T mode) :
+  m_bh1750(bh1750_init(bus, addr, mode))
+{
+  if (!m_bh1750)
+    throw std::runtime_error(string(__FUNCTION__) +
+                             ": bh1750_init() failed");
+}
+
+BH1750::~BH1750()
+{
+  bh1750_close(m_bh1750);
+}
+
+void BH1750::reset()
+{
+  bh1750_reset(m_bh1750);
+}
+
+float BH1750::getLux()
+{
+  float lux = 0.0;
+
+  if (bh1750_get_lux(m_bh1750, &lux) != UPM_SUCCESS)
+    throw std::runtime_error(string(__FUNCTION__) +
+                             ": bh1750_get_lux() failed");
+
+  return lux;
+}
+
+void BH1750::powerUp()
+{
+  if (bh1750_power_up(m_bh1750) != UPM_SUCCESS)
+    throw std::runtime_error(string(__FUNCTION__) +
+                             ": bh1750_power_up() failed");
+}
+
+void BH1750::powerDown()
+{
+  if (bh1750_power_down(m_bh1750) != UPM_SUCCESS)
+    throw std::runtime_error(string(__FUNCTION__) +
+                             ": bh1750_power_down() failed");
+}
+
+void BH1750::setOpmode(BH1750_OPMODES_T mode)
+{
+  if (bh1750_set_opmode(m_bh1750, mode) != UPM_SUCCESS)
+    throw std::runtime_error(string(__FUNCTION__) +
+                             ": bh1750_set_opmode() failed");
+}
+
+void BH1750::sendCommand(uint8_t cmd)
+{
+  if (bh1750_send_command(m_bh1750, cmd) != UPM_SUCCESS)
+    throw std::runtime_error(string(__FUNCTION__) +
+                             ": bh1750_send_command() failed");
+}
+
+uint16_t BH1750::readData()
+{
+  uint16_t data = 0;
+
+  if (bh1750_read_data(m_bh1750, &data) != UPM_SUCCESS)
+    throw std::runtime_error(string(__FUNCTION__) +
+                             ": bh1750_read_data() failed");
+
+  return data;
+}