static int pctv452e_rc_query(struct dvb_usb_device *d)
{
    struct pctv452e_state *state = (struct pctv452e_state *)d->priv;
    int ret, i;
    u8 id;

    mutex_lock(&state->ca_mutex);
    id = state->c++;

    /* prepare command header  */
    state->data[0] = SYNC_BYTE_OUT;
    state->data[1] = id;
    state->data[2] = PCTV_CMD_IR;
    state->data[3] = 0;

    /* send ir request */
    ret = dvb_usb_generic_rw(d, state->data, 4,
                 state->data, PCTV_ANSWER_LEN, 0);
    if (ret != 0)
        goto ret;

    if (debug > 3) {