I2C: Add explicit pinmap support

Author: mprse

drivers/I2C.h

@@ -101,6 +101,12 @@ class I2C : private NonCopyable<I2C> {
      */
     I2C(PinName sda, PinName scl);
 
+    /** Create an I2C Master interface, connected to the specified pins
+     *
+     *  @param explicit_pinmap reference to strucure which holds static pinmap.
+     */
+    I2C(const i2c_pinmap_t &explicit_pinmap);
+
     /** Set the frequency of the I2C interface
      *
      *  @param hz The bus frequency in hertz

drivers/I2CSlave.h

@@ -86,6 +86,12 @@ class I2CSlave {
      */
     I2CSlave(PinName sda, PinName scl);
 
+    /** Create an I2C Slave interface, connected to the specified pins.
+     *
+     *  @param explicit_pinmap reference to strucure which holds static pinmap.
+     */
+    I2CSlave(const i2c_pinmap_t &explicit_pinmap);
+
     /** Set the frequency of the I2C interface.
      *
      *  @param hz The bus frequency in Hertz.

drivers/source/I2C.cpp

@@ -47,6 +47,23 @@ I2C::I2C(PinName sda, PinName scl) :
     unlock();
 }
 
+I2C::I2C(const i2c_pinmap_t &explicit_pinmap) :
+#if DEVICE_I2C_ASYNCH
+    _irq(this), _usage(DMA_USAGE_NEVER), _deep_sleep_locked(false),
+#endif
+    _i2c(), _hz(100000)
+{
+    lock();
+    // The init function also set the frequency to 100000
+    _sda = explicit_pinmap.sda_pin;
+    _scl = explicit_pinmap.scl_pin;
+    recover(explicit_pinmap.sda_pin, explicit_pinmap.scl_pin);
+    i2c_init_direct(&_i2c, &explicit_pinmap);
+    // Used to avoid unnecessary frequency updates
+    _owner = this;
+    unlock();
+}
+
 void I2C::frequency(int hz)
 {
     lock();

drivers/source/I2CSlave.cpp

@@ -27,6 +27,13 @@ I2CSlave::I2CSlave(PinName sda, PinName scl) : _i2c()
     i2c_slave_mode(&_i2c, 1);
 }
 
+I2CSlave::I2CSlave(const i2c_pinmap_t &explicit_pinmap) : _i2c()
+{
+    i2c_init_direct(&_i2c, &explicit_pinmap);
+    i2c_frequency(&_i2c, 100000);
+    i2c_slave_mode(&_i2c, 1);
+}
+
 void I2CSlave::frequency(int hz)
 {
     i2c_frequency(&_i2c, hz);