From 1e4516d0266679a67ad8487d6d17448b76d8c211 Mon Sep 17 00:00:00 2001
From: Brendan Le Foll <brendan.le.foll@intel.com>
Date: Fri, 22 Apr 2016 11:58:57 +0100
Subject: [PATCH] i2c: Add exceptions for C++ i2c errors

Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>
---
 api/mraa/i2c.hpp | 23 ++++++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/api/mraa/i2c.hpp b/api/mraa/i2c.hpp
index cd3c31c..af02c95 100644
--- a/api/mraa/i2c.hpp
+++ b/api/mraa/i2c.hpp
@@ -103,12 +103,17 @@ class I2c
     /**
      * Read exactly one byte from the bus
      *
+     * @throws std::invalid_argument in case of error
      * @return char read from the bus
      */
     uint8_t
     readByte()
     {
-        return (uint8_t) mraa_i2c_read_byte(m_i2c);
+        int x = mraa_i2c_read_byte(m_i2c);
+        if (x == -1) {
+            throw std::invalid_argument("Unknown error in I2c::readByte()");
+        }
+        return (uint8_t) x;
     }
 
     /**
@@ -128,24 +133,36 @@ class I2c
      * Read byte from an i2c register
      *
      * @param reg Register to read from
+     *
+     * @throws std::invalid_argument in case of error
      * @return char read from register
      */
     uint8_t
     readReg(uint8_t reg)
     {
-        return mraa_i2c_read_byte_data(m_i2c, reg);
+        int x = mraa_i2c_read_byte_data(m_i2c, reg);
+        if (x == -1) {
+            throw std::invalid_argument("Unknown error in I2c::readReg()");
+        }
+        return (uint8_t) x;
     }
 
     /**
      * Read word from an i2c register
      *
      * @param reg Register to read from
+     *
+     * @throws std::invalid_argument in case of error
      * @return char read from register
      */
     uint16_t
     readWordReg(uint8_t reg)
     {
-        return mraa_i2c_read_word_data(m_i2c, reg);
+        int x = mraa_i2c_read_word_data(m_i2c, reg);
+	if (x == -1) {
+            throw std::invalid_argument("Unknown error in I2c::readReg()");
+        }
+        return (uint16_t) x;
     }
 
     /**