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/* Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
/* I2C interface for Chrome EC */
#ifndef __CROS_EC_I2C_H
#define __CROS_EC_I2C_H
#include "common.h"
/* Flags for slave address field, in addition to the 8-bit address */
#define I2C_FLAG_BIG_ENDIAN 0x100 /* 16 byte values are MSB-first */
/* Initializes the module. */
int i2c_init(void);
/* Reads a 16-bit register from the slave at 8-bit slave address
* <slaveaddr>, at the specified 8-bit <offset> in the slave's address
* space. */
int i2c_read16(int port, int slave_addr, int offset, int* data);
/* Writes a 16-bit register to the slave at 8-bit slave address
* <slaveaddr>, at the specified 8-bit <offset> in the slave's address
* space. */
int i2c_write16(int port, int slave_addr, int offset, int data);
/* Reads an 8-bit register from the slave at 8-bit slave address
* <slaveaddr>, at the specified 8-bit <offset> in the slave's address
* space. */
int i2c_read8(int port, int slave_addr, int offset, int* data);
/* Writes an 8-bit register to the slave at 8-bit slave address
* <slaveaddr>, at the specified 8-bit <offset> in the slave's address
* space. */
int i2c_write8(int port, int slave_addr, int offset, int data);
/* Read ascii string using smbus read block protocol.
* Read bytestream from <slaveaddr>:<offset> with format:
* [length_N] [byte_0] [byte_1] ... [byte_N-1]
*
* <len> : the max length of receving buffer. to read N bytes
* ascii, len should be at least N+1 to include the
* terminating 0.
* <len> == 0 : buffer size > 255
*/
int i2c_read_string(int port, int slave_addr, int offset, uint8_t *data,
int len);
#endif /* __CROS_EC_I2C_H */
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