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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2007 by Michael Sevakis
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#ifndef I2C_IMX31_H
#define I2C_IMX31_H
#include <stdbool.h>
#include "semaphore.h"
/* I2C module usage masks */
#define USE_I2C1_MODULE (1 << 0)
#define USE_I2C2_MODULE (1 << 1)
#define USE_I2C3_MODULE (1 << 2)
enum i2c_module_number
{
__I2C_NUM_START = -1,
#if (I2C_MODULE_MASK & USE_I2C1_MODULE)
I2C1_NUM,
#endif
#if (I2C_MODULE_MASK & USE_I2C2_MODULE)
I2C2_NUM,
#endif
#if (I2C_MODULE_MASK & USE_I2C3_MODULE)
I2C3_NUM,
#endif
I2C_NUM_I2C,
};
struct i2c_node
{
enum i2c_module_number num; /* Module that this node uses */
unsigned int ifdr; /* Maximum frequency for node */
unsigned char addr; /* Slave address on module */
};
struct i2c_transfer_desc;
typedef void (*i2c_transfer_cb_fn_type)(struct i2c_transfer_desc *);
/* Basic transfer descriptor for normal asynchronous read/write */
struct i2c_transfer_desc
{
struct i2c_node *node;
const unsigned char *txdata;
int txcount;
unsigned char *rxdata;
int rxcount;
i2c_transfer_cb_fn_type callback;
struct i2c_transfer_desc *next;
};
/* Extended transfer descriptor for synchronous read/write that handles
thread wait and wakeup */
struct i2c_sync_transfer_desc
{
struct i2c_transfer_desc xfer;
struct semaphore sema;
};
/* One-time init of i2c driver */
void i2c_init(void);
/* Enable or disable the node - modules will be switched on/off accordingly. */
void i2c_enable_node(struct i2c_node *node, bool enable);
/* Send and/or receive data on the specified node asynchronously */
bool i2c_transfer(struct i2c_transfer_desc *xfer);
/* Read bytes from a device on the I2C bus, with optional sub-addressing
* If addr < 0, then raw read without sub-addressing */
int i2c_read(struct i2c_node *node, int addr, unsigned char *data,
int data_count);
/* Write bytes to a device on the I2C bus */
int i2c_write(struct i2c_node *node, const unsigned char *data,
int data_count);
#endif /* I2C_IMX31_H */
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