File content as of revision 0:fd0d7bdfcdc2:

/* mbed Microcontroller Library
 * Copyright (c) 2006-2012 ARM Limited
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
#include "I2C.h"

#if DEVICE_I2C

namespace mbed {

I2C *I2C::_owner = NULL;

I2C::I2C(PinName sda, PinName scl) {
    // The init function also set the frequency to 100000
    i2c_init(&_i2c, sda, scl);
    _hz = 100000;
    
    // Used to avoid unnecessary frequency updates
    _owner = this;
}

void I2C::frequency(int hz) {
    _hz = hz;
    
    // We want to update the frequency even if we are already the bus owners
    i2c_frequency(&_i2c, _hz);
    
    // Updating the frequency of the bus we become the owners of it
    _owner = this;
}

void I2C::aquire() {
    if (_owner != this) {
        i2c_frequency(&_i2c, _hz);
        _owner = this;
    }
}

// write - Master Transmitter Mode
int I2C::write(int address, const char* data, int length, bool repeated) {
    aquire(); 
    
    int stop = (repeated) ? 0 : 1;
    int retval = i2c_write(&_i2c, address, data, length, stop);
    
    return retval;
}

int I2C::write(int data) {
    return i2c_byte_write(&_i2c, data);
}

// read - Master Reciever Mode
int I2C::read(int address, char* data, int length, bool repeated) {
    aquire();
    
    int stop = (repeated) ? 0 : 1;
    int retval = i2c_read(&_i2c, address, data, length, stop);
    
    return retval;
}

int I2C::read(int ack) {
    if (ack) {
        return i2c_byte_read(&_i2c, 0);
    } else {
        return i2c_byte_read(&_i2c, 1);
    }
}

void I2C::start(void) {
    i2c_start(&_i2c);
}

void I2C::stop(void) {
    i2c_stop(&_i2c);
}

} // namespace mbed

#endif