ds1307: throw exception(s) on fatal errors

Signed-off-by: Jon Trulson <jtrulson@ics.com>
Signed-off-by: Mihai Tudor Panu <mihai.tudor.panu@intel.com>

src/ds1307/ds1307.cxx

@@ -27,6 +27,7 @@
 
 #include <iostream>
 #include <string>
+#include <stdexcept>
 
 #include "ds1307.h"
 
@@ -34,20 +35,15 @@ using namespace upm;
 using namespace std;
 
 
-DS1307::DS1307(int bus)
+DS1307::DS1307(int bus) : m_i2c(bus)
 {
   // setup our i2c link
-  m_i2c = mraa_i2c_init(bus);
+  mraa::Result ret = m_i2c.address(DS1307_I2C_ADDR);
-
+  if (ret != mraa::SUCCESS){
-  mraa_result_t ret = mraa_i2c_address(m_i2c, DS1307_I2C_ADDR);
+    throw std::invalid_argument(std::string(__FUNCTION__) +
-
+                                  ": i2c.address() failed");
-  if (ret != MRAA_SUCCESS) 
+    return;
-    cerr << "DS1307: Could not initialize i2c bus. " << endl;
+  }
-}
-
-DS1307::~DS1307()
-{
-  mraa_i2c_stop(m_i2c);
 }
 
 mraa::Result DS1307::writeBytes(uint8_t reg, uint8_t *buffer, int len)
@@ -65,9 +61,14 @@ mraa::Result DS1307::writeBytes(uint8_t reg, uint8_t *buffer, int len)
   for (int i=1; i<(len + 1); i++)
     buf2[i] = buffer[i-1];
 
-  mraa_i2c_address(m_i2c, DS1307_I2C_ADDR);
+  mraa::Result ret = m_i2c.address(DS1307_I2C_ADDR);
+  if (ret != mraa::SUCCESS){
+      throw std::invalid_argument(std::string(__FUNCTION__) +
+                                  ": i2c.address() failed");
+      return ret;
+  }
 
-  return (mraa::Result) mraa_i2c_write(m_i2c, buf2, len + 1);
+  return m_i2c.write(buf2, len + 1);
 }
 
 int DS1307::readBytes(uint8_t reg, uint8_t *buffer, int len)
@@ -75,10 +76,15 @@ int DS1307::readBytes(uint8_t reg, uint8_t *buffer, int len)
   if (!len || !buffer)
     return 0;
 
-  mraa_i2c_address(m_i2c, DS1307_I2C_ADDR);
+  mraa::Result ret = m_i2c.address(DS1307_I2C_ADDR);
-  mraa_i2c_write_byte(m_i2c, reg);
+  if (ret != mraa::SUCCESS){
+      throw std::invalid_argument(std::string(__FUNCTION__) +
+                                  ": i2c.address() failed");
+      return 0;
+  }
+  m_i2c.writeByte(reg);
 
-  return mraa_i2c_read(m_i2c, buffer, len);
+  return m_i2c.read(buffer, len);
 }
 
 bool DS1307::loadTime()
@@ -90,8 +96,8 @@ bool DS1307::loadTime()
   if (bytesRead != 7)
     { 
       // problem
-      cerr << __FUNCTION__ << ": read " << bytesRead <<
+      throw std::runtime_error(std::string(__FUNCTION__) +
-        " bytes, expected 7." << endl;
+                               ": failed to read expected 7 bytes from device");
       return false;
     }
 

src/ds1307/ds1307.h

@@ -77,11 +77,6 @@ namespace upm {
      */
     DS1307(int bus);
 
-    /**
-     * DS1307 destructor
-     */
-    ~DS1307();
-
     /**
      * Loads all the time values
      *
@@ -100,7 +95,7 @@ namespace upm {
     /**
      * Enables an oscillator on the clock.
      *
-     * @return 0 (MRAA_SUCCESS) if successful; non-zero otherwise
+     * @return 0 (mraa::SUCCESS) if successful; non-zero otherwise
      */
     mraa::Result enableClock();
 
@@ -108,7 +103,7 @@ namespace upm {
      * Disables the oscillator on the clock. This prevents the clock
      * from updating any time/date values
      *
-     * @return 0 (MRAA_SUCCESS) if successful; non-zero otherwise
+     * @return 0 (mraa::SUCCESS) if successful; non-zero otherwise
      */
     mraa::Result disableClock();
 
@@ -118,7 +113,7 @@ namespace upm {
      * @param reg Register location to start writing into
      * @param buffer Buffer for data storage
      * @param len Number of bytes to write
-     * @return 0 (MRAA_SUCCESS) if successful; non-zero otherwise
+     * @return 0 (mraa::SUCCESS) if successful; non-zero otherwise
      */
     mraa::Result writeBytes(uint8_t reg, uint8_t *buffer, int len);
 
@@ -191,7 +186,7 @@ namespace upm {
     bool pm;
 
   private:
-    mraa_i2c_context m_i2c;
+    mraa::I2c m_i2c;
   };
 }