UARTSerial: Free resources

drivers/SerialBase.cpp

@@ -30,17 +30,9 @@ SerialBase::SerialBase(PinName tx, PinName rx, int baud) :
     _rx_callback(NULL), _tx_asynch_set(false),
     _rx_asynch_set(false),
 #endif
-    _serial(), _baud(baud)
+    _serial(), _baud(baud), _tx(tx), _rx(rx)
 {
-    // No lock needed in the constructor
-
-    for (size_t i = 0; i < sizeof _irq / sizeof _irq[0]; i++) {
-        _irq[i] = NULL;
-    }
-
-    serial_init(&_serial, tx, rx);
-    serial_baud(&_serial, _baud);
-    serial_irq_handler(&_serial, SerialBase::_irq_handler, (uint32_t)this);
+    _init();
 }
 
 void SerialBase::baud(int baudrate)
@@ -161,6 +153,22 @@ void SerialBase:: unlock()
     // Stub
 }
 
+void SerialBase::_init(void)
+{
+    for (size_t i = 0; i < sizeof _irq / sizeof _irq[0]; i++) {
+        _irq[i] = NULL;
+    }
+
+    serial_init(&_serial, _tx, _rx);
+    serial_baud(&_serial, _baud);
+    serial_irq_handler(&_serial, SerialBase::_irq_handler, (uint32_t)this);
+}
+
+void SerialBase::_deinit(void)
+{
+    serial_free(&_serial);
+}
+
 SerialBase::~SerialBase()
 {
     // No lock needed in destructor
@@ -169,6 +177,8 @@ SerialBase::~SerialBase()
     for (int irq = 0; irq < IrqCnt; irq++) {
         attach(NULL, (IrqType)irq);
     }
+
+    _deinit();
 }
 
 #if DEVICE_SERIAL_FC

drivers/SerialBase.h

@@ -162,6 +162,14 @@ class SerialBase : private NonCopyable<SerialBase> {
     /** Release exclusive access to this serial port
      */
     virtual void unlock(void);
+
+    /** Initialize serial port
+     */
+    void _init(void);
+
+    /** Deinitialize serial port
+     */
+    void _deinit(void);
 #endif
 public:
 
@@ -304,6 +312,8 @@ class SerialBase : private NonCopyable<SerialBase> {
     serial_t         _serial;
     Callback<void()> _irq[IrqCnt];
     int              _baud;
+    PinName          _rx;
+    PinName          _tx;
 #endif
 };
 

drivers/UARTSerial.cpp

@@ -371,8 +371,13 @@ void UARTSerial::disable_tx_irq()
 
 int UARTSerial::enable_input(bool enabled)
 {
-    core_util_critical_section_enter();
+    api_lock();
     if (_rx_enabled != enabled) {
+        if (enabled && !_tx_enabled) {
+            _init();
+        }
+
+        core_util_critical_section_enter();
         if (enabled) {
             UARTSerial::rx_irq();
             if (!_rxbuf.full()) {
@@ -381,17 +386,27 @@ int UARTSerial::enable_input(bool enabled)
         } else {
             disable_rx_irq();
         }
+        core_util_critical_section_exit();
+
         _rx_enabled = enabled;
-    }
-    core_util_critical_section_exit();
 
+        if (!enabled && !_tx_enabled) {
+            _deinit();
+        }
+    }
+    api_unlock();
     return 0;
 }
 
 int UARTSerial::enable_output(bool enabled)
 {
-    core_util_critical_section_enter();
+    api_lock();
     if (_tx_enabled != enabled) {
+        if (enabled && !_rx_enabled) {
+            _init();
+        }
+
+        core_util_critical_section_enter();
         if (enabled) {
             UARTSerial::tx_irq();
             if (!_txbuf.empty()) {
@@ -400,10 +415,15 @@ int UARTSerial::enable_output(bool enabled)
         } else {
             disable_tx_irq();
         }
+        core_util_critical_section_exit();
+
         _tx_enabled = enabled;
-    }
-    core_util_critical_section_exit();
 
+        if (!enabled && !_rx_enabled) {
+            _deinit();
+        }
+    }
+    api_unlock();
     return 0;
 }