static int pn544_hci_im_transceive()

in pn544/pn544.c [602:664]

• 52 lines of code
• 9 McCabe index (conditional complexity)

static int pn544_hci_im_transceive(struct nfc_hci_dev *hdev,
				   struct nfc_target *target,
				   struct sk_buff *skb, data_exchange_cb_t cb,
				   void *cb_context)
{
	struct pn544_hci_info *info = nfc_hci_get_clientdata(hdev);

	pr_info(DRIVER_DESC ": %s for gate=%d\n", __func__,
		target->hci_reader_gate);

	switch (target->hci_reader_gate) {
	case NFC_HCI_RF_READER_A_GATE:
		if (target->supported_protocols & NFC_PROTO_MIFARE_MASK) {
			/*
			 * It seems that pn544 is inverting key and UID for
			 * MIFARE authentication commands.
			 */
			if (skb->len == MIFARE_CMD_LEN &&
			    (skb->data[0] == MIFARE_CMD_AUTH_KEY_A ||
			     skb->data[0] == MIFARE_CMD_AUTH_KEY_B)) {
				u8 uid[MIFARE_UID_LEN];
				u8 *data = skb->data + MIFARE_CMD_HEADER;

				memcpy(uid, data + MIFARE_KEY_LEN,
				       MIFARE_UID_LEN);
				memmove(data + MIFARE_UID_LEN, data,
					MIFARE_KEY_LEN);
				memcpy(data, uid, MIFARE_UID_LEN);
			}

			return nfc_hci_send_cmd_async(hdev,
						      target->hci_reader_gate,
						      PN544_MIFARE_CMD,
						      skb->data, skb->len,
						      cb, cb_context);
		} else
			return 1;
	case PN544_RF_READER_F_GATE:
		*(u8 *)skb_push(skb, 1) = 0;
		*(u8 *)skb_push(skb, 1) = 0;

		info->async_cb_type = PN544_CB_TYPE_READER_F;
		info->async_cb = cb;
		info->async_cb_context = cb_context;

		return nfc_hci_send_cmd_async(hdev, target->hci_reader_gate,
					      PN544_FELICA_RAW, skb->data,
					      skb->len,
					      pn544_hci_data_exchange_cb, info);
	case PN544_RF_READER_JEWEL_GATE:
		return nfc_hci_send_cmd_async(hdev, target->hci_reader_gate,
					      PN544_JEWEL_RAW_CMD, skb->data,
					      skb->len, cb, cb_context);
	case PN544_RF_READER_NFCIP1_INITIATOR_GATE:
		*(u8 *)skb_push(skb, 1) = 0;

		return nfc_hci_send_event(hdev, target->hci_reader_gate,
					PN544_HCI_EVT_SND_DATA, skb->data,
					skb->len);
	default:
		return 1;
	}
}