IBASE IB113 - Manual (Page 54)

54
IB113
return -1;
}
if (address < 0x03 || address > 0x77) {
fprintf(stderr, "Error: Chip address out of range "
"(0x03-0x77)!\n");
return -2;
}
return address;
}
int open_i2c_dev(int i2cbus, char *filename, size_t size, int quiet)
{
int file;
snprintf(filename, size, "/dev/i2c/%d", i2cbus);
filename[size - 1] = '\0';
file = open(filename, O_RDWR);
if (file < 0 && (errno == ENOENT || errno == ENOTDIR)) {
sprintf(filename, "/dev/i2c-%d", i2cbus);
file = open(filename, O_RDWR);
}
if (file < 0 && !quiet) {
if (errno == ENOENT) {
fprintf(stderr, "Error: Could not open file "
"`/dev/i2c-%d' or `/dev/i2c/%d': %s\n",
i2cbus, i2cbus, strerror(ENOENT));
} else {
fprintf(stderr, "Error: Could not open file "
"`%s': %s\n", filename, strerror(errno));
if (errno == EACCES)
fprintf(stderr, "Run as root?\n");
}
}
return file;
}
int set_slave_addr(int file, int address, int force)
{
/* With force, let the user read from/write to the registers
even when a driver is also running */
if (ioctl(file, force ? I2C_SLAVE_FORCE : I2C_SLAVE, address) < 0) {
fprintf(stderr,
"Error: Could not set address to 0x%02x: %s\n",
address, strerror(errno));
return -errno;
}
return 0;
}
/*
i2cbusses.h
*/
#ifndef _I2CBUSSES_H
#define _I2CBUSSES_H
#include <unistd.h>
struct i2c_adap {
int nr;
char *name;
const char *funcs;
const char *algo;
};