Callback: Adopt better use of assignment/call operators

drivers/InterruptIn.cpp

@@ -27,8 +27,8 @@ InterruptIn::InterruptIn(PinName pin) : gpio(),
                                         _fall() {
     // No lock needed in the constructor
 
-    _rise.attach(donothing);
+    _rise = donothing;
-    _fall.attach(donothing);
+    _fall = donothing;
 
     gpio_irq_init(&gpio_irq, pin, (&InterruptIn::_irq_handler), (uint32_t)this);
     gpio_init_in(&gpio, pin);
@@ -53,10 +53,10 @@ void InterruptIn::mode(PinMode pull) {
 void InterruptIn::rise(Callback<void()> func) {
     core_util_critical_section_enter();
     if (func) {
-        _rise.attach(func);
+        _rise = func;
         gpio_irq_set(&gpio_irq, IRQ_RISE, 1);
     } else {
-        _rise.attach(donothing);
+        _rise = donothing;
         gpio_irq_set(&gpio_irq, IRQ_RISE, 0);
     }
     core_util_critical_section_exit();
@@ -65,10 +65,10 @@ void InterruptIn::rise(Callback<void()> func) {
 void InterruptIn::fall(Callback<void()> func) {
     core_util_critical_section_enter();
     if (func) {
-        _fall.attach(func);
+        _fall = func;
         gpio_irq_set(&gpio_irq, IRQ_FALL, 1);
     } else {
-        _fall.attach(donothing);
+        _fall = donothing;
         gpio_irq_set(&gpio_irq, IRQ_FALL, 0);
     }
     core_util_critical_section_exit();
@@ -77,8 +77,8 @@ void InterruptIn::fall(Callback<void()> func) {
 void InterruptIn::_irq_handler(uint32_t id, gpio_irq_event event) {
     InterruptIn *handler = (InterruptIn*)id;
     switch (event) {
-        case IRQ_RISE: handler->_rise.call(); break;
+        case IRQ_RISE: handler->_rise(); break;
-        case IRQ_FALL: handler->_fall.call(); break;
+        case IRQ_FALL: handler->_fall(); break;
         case IRQ_NONE: break;
     }
 }

drivers/SerialBase.cpp

@@ -32,7 +32,7 @@ SerialBase::SerialBase(PinName tx, PinName rx, int baud) :
     // No lock needed in the constructor
 
     for (size_t i = 0; i < sizeof _irq / sizeof _irq[0]; i++) {
-        _irq[i].attach(donothing);
+        _irq[i] = donothing;
     }
 
     serial_init(&_serial, tx, rx);
@@ -73,10 +73,10 @@ void SerialBase::attach(Callback<void()> func, IrqType type) {
     // Disable interrupts when attaching interrupt handler
     core_util_critical_section_enter();
     if (func) {
-        _irq[type].attach(func);
+        _irq[type] = func;
         serial_irq_set(&_serial, (SerialIrq)type, 1);
     } else {
-        _irq[type].attach(donothing);
+        _irq[type] = donothing;
         serial_irq_set(&_serial, (SerialIrq)type, 0);
     }
     core_util_critical_section_exit();
@@ -85,7 +85,7 @@ void SerialBase::attach(Callback<void()> func, IrqType type) {
 
 void SerialBase::_irq_handler(uint32_t id, SerialIrq irq_type) {
     SerialBase *handler = (SerialBase*)id;
-    handler->_irq[irq_type].call();
+    handler->_irq[irq_type]();
 }
 
 int SerialBase::_base_getc() {

drivers/Ticker.cpp

@@ -25,7 +25,7 @@ namespace mbed {
 void Ticker::detach() {
     core_util_critical_section_enter();
     remove();
-    _function.attach(0);
+    _function = 0;
     core_util_critical_section_exit();
 }
 
@@ -39,7 +39,7 @@ void Ticker::setup(timestamp_t t) {
 
 void Ticker::handler() {
     insert(event.timestamp + _delay);
-    _function.call();
+    _function();
 }
 
 } // namespace mbed

drivers/Ticker.h

@@ -101,7 +101,7 @@ public:
      *  @param t the time between calls in micro-seconds
      */
     void attach_us(Callback<void()> func, timestamp_t t) {
-        _function.attach(func);
+        _function = func;
         setup(t);
     }
 

features/netsocket/Socket.cpp

@@ -42,7 +42,7 @@ nsapi_error_t Socket::open(NetworkStack *stack)
     }
 
     _socket = socket;
-    _event.attach(this, &Socket::event);
+    _event = callback(this, &Socket::event);
     _stack->socket_attach(_socket, Callback<void()>::thunk, &_event);
 
     _lock.unlock();