i2c-dev-26.h

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/*
    $Id: i2c-dev-26.h,v 1.3 2005/02/19 14:39:08 dwalters Exp $
    
    i2c-dev-26.h  compatibility layer for SMBus char device interface

    Copyright (C) 1995-97 Simon G. Vogl
    Copyright (C) 1998-99 Frodo Looijaard

    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.

    Changes:
    
    - Adapted by Dafydd Walters in February 2005 for inclusion in the Open
      Automaton Project, from Vogl and Looijaard's original code which 
      appeared in early versions of the i2c-dev.h kernel header.
      
*/

#ifndef _I2C_DEV_26_H
#define _I2C_DEV_26_H

#include <linux/types.h>
#include <linux/i2c.h>
#include <linux/i2c-dev.h>
#include <sys/ioctl.h>

static inline __s32 oap_i2c_smbus_access(int file, char read_write, __u8 command, 
                                     int size, union i2c_smbus_data *data)
{
    struct i2c_smbus_ioctl_data args;

    args.read_write = read_write;
    args.command = command;
    args.size = size;
    args.data = data;
    return ioctl(file,I2C_SMBUS,&args);
}

static inline __s32 oap_i2c_smbus_write_quick(int file, __u8 value)
{
    return oap_i2c_smbus_access(file,value,0,I2C_SMBUS_QUICK,NULL);
}

static inline __s32 oap_i2c_smbus_read_byte(int file)
{
    union i2c_smbus_data data;
    if (oap_i2c_smbus_access(file,I2C_SMBUS_READ,0,I2C_SMBUS_BYTE,&data))
        return -1;
    else
        return 0x0FF & data.byte;
}

static inline __s32 oap_i2c_smbus_write_byte(int file, __u8 value)
{
    return oap_i2c_smbus_access(file,I2C_SMBUS_WRITE,value,
                            I2C_SMBUS_BYTE,NULL);
}

static inline __s32 oap_i2c_smbus_read_byte_data(int file, __u8 command)
{
    union i2c_smbus_data data;
    if (oap_i2c_smbus_access(file,I2C_SMBUS_READ,command,
                         I2C_SMBUS_BYTE_DATA,&data))
        return -1;
    else
        return 0x0FF & data.byte;
}

static inline __s32 oap_i2c_smbus_write_byte_data(int file, __u8 command, 
                                              __u8 value)
{
    union i2c_smbus_data data;
    data.byte = value;
    return oap_i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
                            I2C_SMBUS_BYTE_DATA, &data);
}

static inline __s32 oap_i2c_smbus_read_word_data(int file, __u8 command)
{
    union i2c_smbus_data data;
    if (oap_i2c_smbus_access(file,I2C_SMBUS_READ,command,
                         I2C_SMBUS_WORD_DATA,&data))
        return -1;
    else
    return 0x0FFFF & data.word;
}

static inline __s32 oap_i2c_smbus_write_word_data(int file, __u8 command, 
                                              __u16 value)
{
    union i2c_smbus_data data;
    data.word = value;
    return oap_i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
                            I2C_SMBUS_WORD_DATA, &data);
}

static inline __s32 oap_i2c_smbus_process_call(int file, __u8 command, __u16 value)
{
    union i2c_smbus_data data;
    data.word = value;
    if (oap_i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
                         I2C_SMBUS_PROC_CALL,&data))
        return -1;
    else
        return 0x0FFFF & data.word;
}


static inline __s32 oap_i2c_smbus_read_block_data(int file, __u8 command, 
                                              __u8 *values)
{
    union i2c_smbus_data data;
    int i;
    if (oap_i2c_smbus_access(file,I2C_SMBUS_READ,command,
                         I2C_SMBUS_BLOCK_DATA,&data))
        return -1;
    else {
        for (i = 1; i <= data.block[0]; i++)
            values[i-1] = data.block[i];
            return data.block[0];
    }
}

static inline __s32 oap_i2c_smbus_write_block_data(int file, __u8 command, 
                                               __u8 length, __u8 *values)
{
    union i2c_smbus_data data;
    int i;
    if (length > 32)
        length = 32;
    for (i = 1; i <= length; i++)
        data.block[i] = values[i-1];
    data.block[0] = length;
    return oap_i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
                            I2C_SMBUS_BLOCK_DATA, &data);
}

static inline __s32 oap_i2c_smbus_write_i2c_block_data(int file, __u8 command,
                                               __u8 length, __u8 *values)
{
    union i2c_smbus_data data;
    int i;
    if (length > 32)
        length = 32;
    for (i = 1; i <= length; i++)
        data.block[i] = values[i-1];
    data.block[0] = length;
    return oap_i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
                            I2C_SMBUS_I2C_BLOCK_DATA, &data);
}

#endif