Hi, I am writing something to try and communicate with an i2c device, particularly, reading register values.

According to the datasheet, the device has 1-byte addresses and 2-byte data.  So I have set up the read function as 
follows.  Can someone tell me if I am doing the right thing? I kept getting error 5 (no error) as a result of the devctl
 call.

	struct {
		i2c_sendrecv_t  hdr;
		unsigned char   bytes[2];
	} msg;

	msg.hdr.slave.addr = dev->i2c_devaddr;
	msg.hdr.slave.fmt = I2C_ADDRFMT_7BIT;
	msg.hdr.send_len = 1;
	msg.hdr.recv_len = 2;
	msg.hdr.stop = 1;

	msg.bytes[0] = reg;

	if (EOK != (ret = devctl(dev->i2c_fd, DCMD_I2C_SENDRECV, &msg, sizeof(msg), &bytes))) {
		fprintf(stderr, "%s:   devctl() failed, error = %d - %s\n", MODULE_NAME, ret, strerror(errno));
		return -1;
	}

	*data = msg.bytes[0];