/***************************************************************************
????copyright????????????:?（C）?by?2002-2003?Stefano?Barbato
????email????????????????:?stefano@codesink.org

????$Id:?24cXX.c?4230?2006-11-10?09:22:12Z?khali?$
?***************************************************************************/

/***************************************************************************
?*?????????????????????????????????????????????????????????????????????????*
?*???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?
#include?
#include?
#include?
#include?
#include?
#include?
#include?
#include?
#include?
#include?“24cXX.h“

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?		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?		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]?<	if（r?		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?fd?r;
	unsigned?long?funcs;
	e->fd?=?e->addr?=?0;
	e->dev?=?0;
	
	fd?=?open（dev_fqn?O_RDWR）;
	if（fd?<=?0）
		return?-1;

	//?get?funcs?list
	if（（r?=?ioctl（fd?I2C_FUNCS?&funcs）?		return?r;

	
	//?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））?		return?r;
	e->fd?=?