static void bcsp_complete_rx_pkt()

in hci_bcsp.c [474:572]

• 71 lines of code
• 17 McCabe index (conditional complexity)

static void bcsp_complete_rx_pkt(struct hci_uart *hu)
{
	struct bcsp_struct *bcsp = hu->priv;
	int pass_up = 0;

	if (bcsp->rx_skb->data[0] & 0x80) {	/* reliable pkt */
		BT_DBG("Received seqno %u from card", bcsp->rxseq_txack);

		/* check the rx sequence number is as expected */
		if ((bcsp->rx_skb->data[0] & 0x07) == bcsp->rxseq_txack) {
			bcsp->rxseq_txack++;
			bcsp->rxseq_txack %= 0x8;
		} else {
			/* handle re-transmitted packet or
			 * when packet was missed
			 */
			BT_ERR("Out-of-order packet arrived, got %u expected %u",
			       bcsp->rx_skb->data[0] & 0x07, bcsp->rxseq_txack);

			/* do not process out-of-order packet payload */
			pass_up = 2;
		}

		/* send current txack value to all received reliable packets */
		bcsp->txack_req = 1;

		/* If needed, transmit an ack pkt */
		hci_uart_tx_wakeup(hu);
	}

	bcsp->rxack = (bcsp->rx_skb->data[0] >> 3) & 0x07;
	BT_DBG("Request for pkt %u from card", bcsp->rxack);

	/* handle received ACK indications,
	 * including those from out-of-order packets
	 */
	bcsp_pkt_cull(bcsp);

	if (pass_up != 2) {
		if ((bcsp->rx_skb->data[1] & 0x0f) == 6 &&
		    (bcsp->rx_skb->data[0] & 0x80)) {
			hci_skb_pkt_type(bcsp->rx_skb) = HCI_ACLDATA_PKT;
			pass_up = 1;
		} else if ((bcsp->rx_skb->data[1] & 0x0f) == 5 &&
			   (bcsp->rx_skb->data[0] & 0x80)) {
			hci_skb_pkt_type(bcsp->rx_skb) = HCI_EVENT_PKT;
			pass_up = 1;
		} else if ((bcsp->rx_skb->data[1] & 0x0f) == 7) {
			hci_skb_pkt_type(bcsp->rx_skb) = HCI_SCODATA_PKT;
			pass_up = 1;
		} else if ((bcsp->rx_skb->data[1] & 0x0f) == 1 &&
			   !(bcsp->rx_skb->data[0] & 0x80)) {
			bcsp_handle_le_pkt(hu);
			pass_up = 0;
		} else {
			pass_up = 0;
		}
	}

	if (pass_up == 0) {
		struct hci_event_hdr hdr;
		u8 desc = (bcsp->rx_skb->data[1] & 0x0f);

		if (desc != 0 && desc != 1) {
			if (hciextn) {
				desc |= 0xc0;
				skb_pull(bcsp->rx_skb, 4);
				memcpy(skb_push(bcsp->rx_skb, 1), &desc, 1);

				hdr.evt = 0xff;
				hdr.plen = bcsp->rx_skb->len;
				memcpy(skb_push(bcsp->rx_skb, HCI_EVENT_HDR_SIZE), &hdr, HCI_EVENT_HDR_SIZE);
				hci_skb_pkt_type(bcsp->rx_skb) = HCI_EVENT_PKT;

				hci_recv_frame(hu->hdev, bcsp->rx_skb);
			} else {
				BT_ERR("Packet for unknown channel (%u %s)",
				       bcsp->rx_skb->data[1] & 0x0f,
				       bcsp->rx_skb->data[0] & 0x80 ?
				       "reliable" : "unreliable");
				kfree_skb(bcsp->rx_skb);
			}
		} else
			kfree_skb(bcsp->rx_skb);
	} else if (pass_up == 1) {
		/* Pull out BCSP hdr */
		skb_pull(bcsp->rx_skb, 4);

		hci_recv_frame(hu->hdev, bcsp->rx_skb);
	} else {
		/* ignore packet payload of already ACKed re-transmitted
		 * packets or when a packet was missed in the BCSP window
		 */
		kfree_skb(bcsp->rx_skb);
	}

	bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
	bcsp->rx_skb = NULL;
}