static int btmrvl_sdio_card_to_host()

in btmrvl_sdio.c [714:835]

• 95 lines of code
• 18 McCabe index (conditional complexity)

static int btmrvl_sdio_card_to_host(struct btmrvl_private *priv)
{
	u16 buf_len = 0;
	int ret, num_blocks, blksz;
	struct sk_buff *skb = NULL;
	u32 type;
	u8 *payload;
	struct hci_dev *hdev = priv->btmrvl_dev.hcidev;
	struct btmrvl_sdio_card *card = priv->btmrvl_dev.card;

	if (!card || !card->func) {
		BT_ERR("card or function is NULL!");
		ret = -EINVAL;
		goto exit;
	}

	/* Read the length of data to be transferred */
	ret = btmrvl_sdio_read_rx_len(card, &buf_len);
	if (ret < 0) {
		BT_ERR("read rx_len failed");
		ret = -EIO;
		goto exit;
	}

	blksz = SDIO_BLOCK_SIZE;
	num_blocks = DIV_ROUND_UP(buf_len, blksz);

	if (buf_len <= SDIO_HEADER_LEN
	    || (num_blocks * blksz) > ALLOC_BUF_SIZE) {
		BT_ERR("invalid packet length: %d", buf_len);
		ret = -EINVAL;
		goto exit;
	}

	/* Allocate buffer */
	skb = bt_skb_alloc(num_blocks * blksz + BTSDIO_DMA_ALIGN, GFP_KERNEL);
	if (!skb) {
		BT_ERR("No free skb");
		ret = -ENOMEM;
		goto exit;
	}

	if ((unsigned long) skb->data & (BTSDIO_DMA_ALIGN - 1)) {
		skb_put(skb, (unsigned long) skb->data &
					(BTSDIO_DMA_ALIGN - 1));
		skb_pull(skb, (unsigned long) skb->data &
					(BTSDIO_DMA_ALIGN - 1));
	}

	payload = skb->data;

	ret = sdio_readsb(card->func, payload, card->ioport,
			  num_blocks * blksz);
	if (ret < 0) {
		BT_ERR("readsb failed: %d", ret);
		ret = -EIO;
		goto exit;
	}

	/* This is SDIO specific header length: byte[2][1][0], type: byte[3]
	 * (HCI_COMMAND = 1, ACL_DATA = 2, SCO_DATA = 3, 0xFE = Vendor)
	 */

	buf_len = payload[0];
	buf_len |= payload[1] << 8;
	buf_len |= payload[2] << 16;

	if (buf_len > blksz * num_blocks) {
		BT_ERR("Skip incorrect packet: hdrlen %d buffer %d",
		       buf_len, blksz * num_blocks);
		ret = -EIO;
		goto exit;
	}

	type = payload[3];

	switch (type) {
	case HCI_ACLDATA_PKT:
	case HCI_SCODATA_PKT:
	case HCI_EVENT_PKT:
		hci_skb_pkt_type(skb) = type;
		skb_put(skb, buf_len);
		skb_pull(skb, SDIO_HEADER_LEN);

		if (type == HCI_EVENT_PKT) {
			if (btmrvl_check_evtpkt(priv, skb))
				hci_recv_frame(hdev, skb);
		} else {
			hci_recv_frame(hdev, skb);
		}

		hdev->stat.byte_rx += buf_len;
		break;

	case MRVL_VENDOR_PKT:
		hci_skb_pkt_type(skb) = HCI_VENDOR_PKT;
		skb_put(skb, buf_len);
		skb_pull(skb, SDIO_HEADER_LEN);

		if (btmrvl_process_event(priv, skb))
			hci_recv_frame(hdev, skb);

		hdev->stat.byte_rx += buf_len;
		break;

	default:
		BT_ERR("Unknown packet type:%d", type);
		BT_ERR("hex: %*ph", blksz * num_blocks, payload);

		kfree_skb(skb);
		skb = NULL;
		break;
	}

exit:
	if (ret) {
		hdev->stat.err_rx++;
		kfree_skb(skb);
	}

	return ret;
}