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/* 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.
 */
#ifndef MBED_I2C_H
#define MBED_I2C_H

#include "platform.h"

#if DEVICE_I2C

#include "i2c_api.h"

namespace mbed {

/** An I2C Master, used for communicating with I2C slave devices
 *
 * Example:
 * @code
 * // Read from I2C slave at address 0x62
 *
 * #include "mbed.h"
 *
 * I2C i2c(p28, p27);
 *
 * int main() {
 *     int address = 0x62;
 *     char data[2];
 *     i2c.read(address, data, 2);
 * }
 * @endcode
 */
class I2C {

public:
    enum RxStatus {
        NoData,
        MasterGeneralCall,
        MasterWrite,
        MasterRead
    };

    enum Acknowledge {
        NoACK = 0,
        ACK   = 1
    };

    /** Create an I2C Master interface, connected to the specified pins
     *
     *  @param sda I2C data line pin
     *  @param scl I2C clock line pin
     */
    I2C(PinName sda, PinName scl);

    /** Set the frequency of the I2C interface
     *
     *  @param hz The bus frequency in hertz
     */
    void frequency(int hz);

    /** Read from an I2C slave
     *
     * Performs a complete read transaction. The bottom bit of
     * the address is forced to 1 to indicate a read.
     *
     *  @param address 8-bit I2C slave address [ addr | 1 ]
     *  @param data Pointer to the byte-array to read data in to 
     *  @param length Number of bytes to read
     *  @param repeated Repeated start, true - don't send stop at end
     *
     *  @returns
     *       0 on success (ack),
     *   non-0 on failure (nack)
     */ 
    int read(int address, char *data, int length, bool repeated = false);

    /** Read a single byte from the I2C bus
     *
     *  @param ack indicates if the byte is to be acknowledged (1 = acknowledge)
     *
     *  @returns
     *    the byte read
     */
    int read(int ack);

    /** Write to an I2C slave
     *
     * Performs a complete write transaction. The bottom bit of
     * the address is forced to 0 to indicate a write.
     *
     *  @param address 8-bit I2C slave address [ addr | 0 ]
     *  @param data Pointer to the byte-array data to send 
     *  @param length Number of bytes to send
     *  @param repeated Repeated start, true - do not send stop at end
     *
     *  @returns
     *       0 on success (ack),
     *   non-0 on failure (nack)
     */ 
    int write(int address, const char *data, int length, bool repeated = false);

    /** Write single byte out on the I2C bus
     *
     *  @param data data to write out on bus
     *
     *  @returns
     *    '1' if an ACK was received,
     *    '0' otherwise
     */
    int write(int data);

    /** Creates a start condition on the I2C bus
     */

    void start(void);

    /** Creates a stop condition on the I2C bus
     */
    void stop(void);

protected:
    void aquire();
    
    i2c_t _i2c;
    static I2C  *_owner;
    int         _hz;
};

} // namespace mbed

#endif

#endif