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/*
* The MIT License (MIT)
*
* Copyright (c) 2015 Matthias P. Braendli
*
* 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 __I2C_H_
#define __I2C_H_
#include <stdint.h>
/* Initialise I2C on the board for both the audio codec and the GPS receiver */
void i2c_init(void);
/* Do an I2C write, return 1 on success, 0 on failure */
int i2c_write(uint8_t device, const uint8_t *txbuf, int len);
/* Do an I2C read into rxbuf.
* Returns number of bytes received, or 0 in case of failure
*/
int i2c_read(uint8_t device, uint8_t *rxbuf, int len);
/* Do an I2C write for the address, and then a read into rxbuf.
* Returns number of bytes received, or 0 in case of failure
*/
int i2c_read_from(uint8_t device, uint8_t address, uint8_t *rxbuf, int len);
/* Start an I2C transaction, keeping exclusive access to I2C */
void i2c_transaction_start(void);
/* End an I2C transaction, unlocking the exclusive access to I2C */
void i2c_transaction_end(void);
#endif // __I2C_H_
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