hdc1000: Added upm support for sensor HDC1000

The HDC1000 is a digital humidity sensor with integrated temperature sensor.

Signed-off-by: Norbert Wesp <nwesp@phytec.de>
Signed-off-by: Mihai Tudor Panu <mihai.tudor.panu@intel.com>

src/hdc1000/hdc1000.cpp

@@ -0,0 +1,147 @@
+/*
+ * Author: Norbert Wesp <nwesp@phytec.de>
+ * Copyright (c) 2017 Phytec Messtechnik GmbH.
+ *
+ * based on: RIOT-driver hdc1000 by Johann Fischer <j.fischer@phytec.de>
+ *
+ * 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 <endian.h>
+
+#include "hdc1000.hpp"
+
+using namespace upm;
+
+HDC1000::HDC1000(int bus, int devAddr) : m_i2ControlCtx(bus) {
+    m_temperature = 0;
+    m_humidity = 0;
+
+    m_name = HDC1000_NAME;
+
+    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");
+    }
+
+    if (checkID() != 0) {
+        /* sensor_id does not match! maybe wrong sensor chosen? */
+        throw std::invalid_argument(std::string(__FUNCTION__) +
+                                    ": checkID() failed");
+    }
+
+    sampleData();
+}
+
+int
+HDC1000::checkID(void)
+{
+    uint8_t tmp[2];
+    uint16_t id;
+    int re = 0;
+
+    re = m_i2ControlCtx.readBytesReg(HDC1000_DEVICE_ID_REG, tmp, 2);
+    if (re != 2) {
+        /* not enough bytes were read! */
+        return -1;
+    }
+
+    id = ((uint16_t)tmp[0] << 8) | tmp[1];
+
+    if (id != HDC1000_DEVICE_ID) {
+        return -1;
+    }
+
+    return 0;
+}
+
+void
+HDC1000::resetSensor(void)
+{
+    mraa::Result ret = m_i2ControlCtx.address(m_controlAddr);
+    if (ret != mraa::SUCCESS) {
+        throw std::invalid_argument(std::string(__FUNCTION__) +
+                                    ": mraa_i2c_address() failed");
+    }
+
+    ret = m_i2ControlCtx.writeByte(0);
+    if (ret != mraa::SUCCESS) {
+        throw std::invalid_argument(std::string(__FUNCTION__) +
+                                    ": mraa_i2c_write_byte() failed");
+    }
+    usleep(SLEEP_SEC);
+}
+
+void
+HDC1000::sampleData(void)
+{
+    uint8_t itemp[4];
+    uint16_t traw, hraw;
+    int re = 0;
+
+    resetSensor();
+
+    mraa::Result ret = m_i2ControlCtx.address(m_controlAddr);
+    if (ret != mraa::SUCCESS) {
+        throw std::invalid_argument(std::string(__FUNCTION__) +
+                                    ": mraa_i2c_address() failed");
+    }
+
+    re = m_i2ControlCtx.read(itemp, 4);
+    if (re != 4) {
+        /* not enough bytes were read! */
+        throw std::invalid_argument(std::string(__FUNCTION__) +
+                                    ": mraa_i2c_read(4) failed");
+    }
+
+    traw = ((uint16_t)itemp[0] << 8) | itemp[1];
+    m_temperature = ((((int32_t)traw * 16500) >> 16) -4000);
+
+    hraw = ((uint16_t)itemp[2] << 8) | itemp[3];
+    m_humidity = (((int32_t)hraw * 10000) >> 16);
+}
+
+float
+HDC1000::getTemperature(int bSampleData)
+{
+    if (bSampleData) {
+        sampleData();
+    }
+    return (float)(m_temperature * 0.01);
+}
+
+float
+HDC1000::getHumidity(int bSampleData)
+{
+    if (bSampleData) {
+        sampleData();
+    }
+    return (float)(m_humidity * 0.01);
+}