diff options
Diffstat (limited to 'eepromer/24cXX.c')
| -rw-r--r-- | eepromer/24cXX.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/eepromer/24cXX.c b/eepromer/24cXX.c new file mode 100644 index 0000000..134e5a1 --- /dev/null +++ b/eepromer/24cXX.c @@ -0,0 +1,182 @@ +/*************************************************************************** + 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 <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 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 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) < 0)) + 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)) < 0) + return r; + 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); + } else { + fprintf(stderr, "ERR: unknown eeprom type\n"); + return -1; + } +} + |