simplify InterruptIn - default parameter instead of multiple constructors

drivers/InterruptIn.cpp

@@ -19,27 +19,14 @@
 
 namespace mbed {
 
-InterruptIn::InterruptIn(PinName pin) : gpio(),
-                                        gpio_irq(),
-                                        _rise(NULL),
-                                        _fall(NULL) {
-    // No lock needed in the constructor
-    irq_init(pin);
-    gpio_init_in(&gpio, pin);
-}
-
 InterruptIn::InterruptIn(PinName pin, PinMode mode) :
                                         gpio(),
                                         gpio_irq(),
                                         _rise(NULL),
                                         _fall(NULL) {
     // No lock needed in the constructor
-    irq_init(pin);
-    gpio_init_in_ex(&gpio, pin, mode);
-}
-
-void InterruptIn::irq_init(PinName pin) {
     gpio_irq_init(&gpio_irq, pin, (&InterruptIn::_irq_handler), (uint32_t)this);
+    gpio_init_in_ex(&gpio, pin, mode);
 }
 
 InterruptIn::~InterruptIn() {

drivers/InterruptIn.h

@@ -61,17 +61,12 @@ class InterruptIn : private NonCopyable<InterruptIn> {
 
 public:
 
-    /** Create an InterruptIn connected to the specified pin
-     *
-     *  @param pin InterruptIn pin to connect to
-     */
-    InterruptIn(PinName pin);
     /** Create an InterruptIn connected to the specified pin,
-     *  and the pin configured to the specified mode.
+     *  with the pin configured to the specified mode.
      *
      *  @param pin InterruptIn pin to connect to
      */
-    InterruptIn(PinName pin, PinMode mode);
+    InterruptIn(PinName pin, PinMode mode = PullDefault);
     virtual ~InterruptIn();
 
     /** Read the input, represented as 0 or 1 (int)
@@ -159,8 +154,6 @@ protected:
 
     Callback<void()> _rise;
     Callback<void()> _fall;
-
-    void irq_init(PinName pin);
 };
 
 } // namespace mbed