ttusb2_msg
ret = ttusb2_msg(d, cmd, data, write_len, rx, read_len);
if (ttusb2_msg(d, CMD_I2C_XFER, obuf, obuf[1]+3, ibuf, obuf[2] + 3) < 0) {
ret = ttusb2_msg(d, CMD_GET_IR_CODE, NULL, 0, rx, sizeof(rx));
ttusb2_msg(d, CMD_POWER, &b, 0, NULL, 0);
return ttusb2_msg(d, CMD_POWER, &b, 1, NULL, 0);