24cxx.c

2440开发板的i2c驱动测试程序

/***************************************************************************
    copyright            : (C) by 2003-2004 Stefano Barbato
    email                : [e-mail]

    $Id: 24cXX.h,v 1.6 2004/02/29 11:05:28 tat Exp $
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 ***************************************************************************/
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <linux/fs.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <errno.h>
#include <assert.h>
#include <string.h>
#include "24cXX.h"


static inline __s32 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 i2c_smbus_write_quick(int file, __u8 value)
{
	return i2c_smbus_access(file,value,0,I2C_SMBUS_QUICK,NULL);
}
	
static inline __s32 i2c_smbus_read_byte(int file)
{
	union i2c_smbus_data data;
	if (i2c_smbus_access(file,I2C_SMBUS_READ,0,I2C_SMBUS_BYTE,&data))
		return -1;
	else
		return 0x0FF & data.byte;
}

static inline __s32 i2c_smbus_write_byte(int file, __u8 value)
{
	return i2c_smbus_access(file,I2C_SMBUS_WRITE,value,
	                        I2C_SMBUS_BYTE,NULL);
}

static inline __s32 i2c_smbus_read_byte_data(int file, __u8 command)
{
	union i2c_smbus_data data;
	if (i2c_smbus_access(file,I2C_SMBUS_READ,command,
	                     I2C_SMBUS_BYTE_DATA,&data))
		return -1;
	else
		return 0x0FF & data.byte;
}

static inline __s32 i2c_smbus_write_byte_data(int file, __u8 command, 
                                              __u8 value)
{
	union i2c_smbus_data data;
	data.byte = value;
	return i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
	                        I2C_SMBUS_BYTE_DATA, &data);
}

static inline __s32 i2c_smbus_read_word_data(int file, __u8 command)
{
	union i2c_smbus_data data;
	if (i2c_smbus_access(file,I2C_SMBUS_READ,command,
	                     I2C_SMBUS_WORD_DATA,&data))
		return -1;
	else
		return 0x0FFFF & data.word;
}

static inline __s32 i2c_smbus_write_word_data(int file, __u8 command, 
                                              __u16 value)
{
	union i2c_smbus_data data;
	data.word = value;
	return i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
	                        I2C_SMBUS_WORD_DATA, &data);
}

static inline __s32 i2c_smbus_process_call(int file, __u8 command, __u16 value)
{
	union i2c_smbus_data data;
	data.word = value;
	if (i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
	                     I2C_SMBUS_PROC_CALL,&data))
		return -1;
	else
		return 0x0FFFF & data.word;
}


/* Returns the number of read bytes */
static inline __s32 i2c_smbus_read_block_data(int file, __u8 command, 
                                              __u8 *values)
{
	union i2c_smbus_data data;
	int i;
	if (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 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 i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
	                        I2C_SMBUS_BLOCK_DATA, &data);
}

/* Returns the number of read bytes */
static inline __s32 i2c_smbus_read_i2c_block_data(int file, __u8 command,
                                                  __u8 *values)
{
	union i2c_smbus_data data;
	int i;
	if (i2c_smbus_access(file,I2C_SMBUS_READ,command,
	                      I2C_SMBUS_I2C_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 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 i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
	                        I2C_SMBUS_I2C_BLOCK_DATA, &data);
}

/* Returns the number of read bytes */
static inline __s32 i2c_smbus_block_process_call(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;
	if (i2c_smbus_access(file,I2C_SMBUS_WRITE,command,
	                     I2C_SMBUS_BLOCK_PROC_CALL,&data))
		return -1;
	else {
		for (i = 1; i <= data.block[0]; i++)
			values[i-1] = data.block[i];
		return data.block[0];
	}
}

static int i2c_write_1b(struct eeprom *e, __u8 buf)
{
	int r;
	// we must simulate a plain I2C byte write with SMBus functions
	r = i2c_smbus_write_byte(e->fd, buf);
	if(r < 0)
		fprintf(stderr, "Error i2c_write_1b: %s\n", strerror(errno));
	usleep(10);
	return r;
}

static int i2c_write_2b(struct eeprom *e, __u8 buf[2])
{
	int r;
	// we must simulate a plain I2C byte write with SMBus functions
	r = i2c_smbus_write_byte_data(e->fd, buf[0], buf[1]);
	if(r < 0)
		fprintf(stderr, "Error i2c_write_2b: %s\n", strerror(errno));
	usleep(10);
	return r;
}

static int i2c_write_3b(struct eeprom *e, __u8 buf[3])
{
	int r;
	// we must simulate a plain I2C byte write with SMBus functions
	// the __u16 data field will be byte swapped by the SMBus protocol
	r = i2c_smbus_write_word_data(e->fd, buf[0], buf[2] << 8 | buf[1]);
	if(r < 0)
		fprintf(stderr, "Error i2c_write_3b: %s\n", strerror(errno));
	usleep(10);
	return r;
}


#define CHECK_I2C_FUNC( var, label ) \
	do { 	if(0 == (var & label)) { \
		fprintf(stderr, "\nError: " \
			#label " function is required. Program halted.\n\n"); \
		exit(1); } \
	} while(0);

int eeprom_open(char *dev_fqn, int addr, int type, struct eeprom* e)
{
	int funcs, fd, r;
	e->fd = e->addr = 0;
	e->dev = 0;
	
	fd = open(dev_fqn, O_RDWR);
	if(fd <= 0)
	{
		fprintf(stderr, "Error eeprom_open: %s\n", strerror(errno));
		return -1;
	}

	// get funcs list
	if((r = ioctl(fd, I2C_FUNCS, &funcs) < 0))
	{
		fprintf(stderr, "Error eeprom_open: %s\n", strerror(errno));
		return -1;
	}

	
	// check for req funcs
	CHECK_I2C_FUNC( funcs, I2C_FUNC_SMBUS_READ_BYTE );
	CHECK_I2C_FUNC( funcs, I2C_FUNC_SMBUS_WRITE_BYTE );
	CHECK_I2C_FUNC( funcs, I2C_FUNC_SMBUS_READ_BYTE_DATA );
	CHECK_I2C_FUNC( funcs, I2C_FUNC_SMBUS_WRITE_BYTE_DATA );
	CHECK_I2C_FUNC( funcs, I2C_FUNC_SMBUS_READ_WORD_DATA );
	CHECK_I2C_FUNC( funcs, I2C_FUNC_SMBUS_WRITE_WORD_DATA );

	// set working device
	if( ( r = ioctl(fd, I2C_SLAVE, addr)) < 0)
	{
		fprintf(stderr, "Error eeprom_open: %s\n", strerror(errno));
		return -1;
	}
	e->fd = fd;
	e->addr = addr;
	e->dev = dev_fqn;
	e->type = type;
	return 0;
}

int eeprom_close(struct eeprom *e)
{
	close(e->fd);
	e->fd = -1;
	e->dev = 0;
	e->type = EEPROM_TYPE_UNKNOWN;
	return 0;
}

#if 0
int eeprom_24c32_write_byte(struct eeprom *e, __u16 mem_addr, __u8 data)
{
	__u8 buf[3] = { (mem_addr >> 8) & 0x00ff, mem_addr & 0x00ff, data };
	return i2c_write_3b(e, buf);
}


int eeprom_24c32_read_current_byte(struct eeprom* e)
{
	ioctl(e->fd, BLKFLSBUF); // clear kernel read buffer
	return i2c_smbus_read_byte(e->fd);
}

int eeprom_24c32_read_byte(struct eeprom* e, __u16 mem_addr)
{
	int r;
	ioctl(e->fd, BLKFLSBUF); // clear kernel read buffer
	__u8 buf[2] = { (mem_addr >> 8) & 0x0ff, mem_addr & 0x0ff };
	r = i2c_write_2b(e, buf);
	if (r < 0)
		return r;
	r = i2c_smbus_read_byte(e->fd);
	return r;
}
#endif


int eeprom_read_current_byte(struct eeprom* e)
{
	ioctl(e->fd, BLKFLSBUF); // clear kernel read buffer
	return i2c_smbus_read_byte(e->fd);
}

int eeprom_read_byte(struct eeprom* e, __u16 mem_addr)
{
	int r;
	ioctl(e->fd, BLKFLSBUF); // clear kernel read buffer
	if(e->type == EEPROM_TYPE_8BIT_ADDR)
	{
		__u8 buf =  mem_addr & 0x0ff;
		r = i2c_write_1b(e, buf);
	} else if(e->type == EEPROM_TYPE_16BIT_ADDR) {
		__u8 buf[2] = { (mem_addr >> 8) & 0x0ff, mem_addr & 0x0ff };
		r = i2c_write_2b(e, buf);
	} else {
		fprintf(stderr, "ERR: unknown eeprom type\n");
		return -1;
	}
	if (r < 0)
		return r;
	r = i2c_smbus_read_byte(e->fd);
	return r;
}

int eeprom_write_byte(struct eeprom *e, __u16 mem_addr, __u8 data)
{
	if(e->type == EEPROM_TYPE_8BIT_ADDR) {
		__u8 buf[2] = { mem_addr & 0x00ff, data };
		return i2c_write_2b(e, buf);
	} else if(e->type == EEPROM_TYPE_16BIT_ADDR) {
		__u8 buf[3] = 
			{ (mem_addr >> 8) & 0x00ff, mem_addr & 0x00ff, data };
		return i2c_write_3b(e, buf);
	} 
	fprintf(stderr, "ERR: unknown eeprom type\n");
	return -1;
}