IBASE SMARC-EVK1 - Manual (Page 75)

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49 IBASE Technology Inc.
break;
case I2C_SMBUS_WORD_DATA:
res = i2c_smbus_write_word_data(file, daddress, value);
break;
case I2C_SMBUS_BLOCK_DATA:
res = i2c_smbus_write_block_data(file, daddress, len, block);
break;
case I2C_SMBUS_I2C_BLOCK_DATA:
res = i2c_smbus_write_i2c_block_data(file, daddress, len, block);
break;
default: /* I2C_SMBUS_BYTE_DATA */
res = i2c_smbus_write_byte_data(file, daddress, value);
break;
}
if (res < 0) {
fprintf(stderr, "Error: Write failed\n");
close(file);
exit(1);
}
if (pec) {
if (ioctl(file, I2C_PEC, 0) < 0) {
fprintf(stderr, "Error: Could not clear PEC: %s\n",
strerror(errno));
close(file);
exit(1);
}
}
if (!readback) { /* We're done */
close(file);
exit(0);
}
switch (size) {
case I2C_SMBUS_BYTE:
res = i2c_smbus_read_byte(file);
value = daddress;
break;
case I2C_SMBUS_WORD_DATA:
res = i2c_smbus_read_word_data(file, daddress);
break;
default: /* I2C_SMBUS_BYTE_DATA */
res = i2c_smbus_read_byte_data(file, daddress);
}
close(file);
if (res < 0) {
printf("Warning - readback failed\n");
} else
if (res != value) {
printf("Warning - data mismatch - wrote "
"0x%0*x, read back 0x%0*x\n",
size == I2C_SMBUS_WORD_DATA ? 4 : 2, value,
size == I2C_SMBUS_WORD_DATA ? 4 : 2, res);
} else {
printf("Value 0x%0*x written, readback matched\n",
size == I2C_SMBUS_WORD_DATA ? 4 : 2, value);
}
exit(0);
}
Utils/headers
/*
i2cbusses: Print the installed i2c busses for both 2.4 and 2.6 kernels.
Part of user-space programs to access for I2C
devices.
*/
/* For strdup and snprintf */