static int nci_transceive(struct nfc_dev *nfc_dev, struct nfc_target *target,
struct sk_buff *skb,
data_exchange_cb_t cb, void *cb_context)
{
struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
int rc;
pr_debug("target_idx %d, len %d\n", target->idx, skb->len);
if (!ndev->target_active_prot) {
pr_err("unable to exchange data, no active target\n");
return -EINVAL;
}
if (test_and_set_bit(NCI_DATA_EXCHANGE, &ndev->flags))
return -EBUSY;
/* store cb and context to be used on receiving data */
ndev->data_exchange_cb = cb;
ndev->data_exchange_cb_context = cb_context;
rc = nci_send_data(ndev, NCI_STATIC_RF_CONN_ID, skb);
if (rc)
clear_bit(NCI_DATA_EXCHANGE, &ndev->flags);
return rc;
}
/* Fragment HCI data over NCI packet.
* NFC Forum NCI 10.2.2 Data Exchange:
* The payload of the Data Packets sent on the Logical Connection SHALL be
* valid HCP packets, as defined within [ETSI_102622]. Each Data Packet SHALL
* contain a single HCP packet. NCI Segmentation and Reassembly SHALL NOT be
* applied to Data Messages in either direction. The HCI fragmentation mechanism
* is used if required.
*/
static int nci_hci_send_data(struct nci_dev *ndev, u8 pipe,
const u8 data_type, const u8 *data,
size_t data_len)
{
struct nci_conn_info *conn_info;
struct sk_buff *skb;
int len, i, r;
u8 cb = pipe;
conn_info = ndev->hci_dev->conn_info;
if (!conn_info)
return -EPROTO;
i = 0;
skb = nci_skb_alloc(ndev, conn_info->max_pkt_payload_len +
NCI_DATA_HDR_SIZE, GFP_KERNEL);
if (!skb)
return -ENOMEM;
skb_reserve(skb, NCI_DATA_HDR_SIZE + 2);
*skb_push(skb, 1) = data_type;
do {
len = conn_info->max_pkt_payload_len;
/* If last packet add NCI_HFP_NO_CHAINING */
if (i + conn_info->max_pkt_payload_len -
(skb->len + 1) >= data_len) {
cb |= NCI_HFP_NO_CHAINING;
len = data_len - i;
} else {
len = conn_info->max_pkt_payload_len - skb->len - 1;
}
*skb_push(skb, 1) = cb;
if (len > 0)
memcpy(skb_put(skb, len), data + i, len);
r = nci_send_data(ndev, conn_info->conn_id, skb);
if (r < 0)
return r;
i += len;
if (i < data_len) {
skb = nci_skb_alloc(ndev,
conn_info->max_pkt_payload_len +
NCI_DATA_HDR_SIZE, GFP_KERNEL);
if (!skb)
return -ENOMEM;
skb_reserve(skb, NCI_DATA_HDR_SIZE + 1);
}
} while (i < data_len);
return i;
}
static int nci_data_exchange(struct nfc_dev *nfc_dev, __u32 target_idx,
struct sk_buff *skb,
data_exchange_cb_t cb,
void *cb_context)
{
struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
nfc_dbg("entry, target_idx %d, len %d", target_idx, skb->len);
if (!ndev->target_active_prot) {
nfc_err("unable to exchange data, no active target");
return -EINVAL;
}
/* store cb and context to be used on receiving data */
ndev->data_exchange_cb = cb;
ndev->data_exchange_cb_context = cb_context;
return nci_send_data(ndev, ndev->conn_id, skb);
}
