/*
* The NFC Controller Interface is the communication protocol between an
* NFC Controller (NFCC) and a Device Host (DH).
*
* Copyright (C) 2011 Texas Instruments, Inc.
*
* Written by Ilan Elias <ilane@ti.com>
*
* Acknowledgements:
* This file is based on hci_event.c, which was written
* by Maxim Krasnyansky.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/bitops.h>
#include <linux/skbuff.h>
#include "../nfc.h"
#include <net/nfc/nci.h>
#include <net/nfc/nci_core.h>
#include <linux/nfc.h>
/* Handle NCI Notification packets */
static void nci_core_conn_credits_ntf_packet(struct nci_dev *ndev,
struct sk_buff *skb)
{
struct nci_core_conn_credit_ntf *ntf = (void *) skb->data;
int i;
pr_debug("num_entries %d\n", ntf->num_entries);
if (ntf->num_entries > NCI_MAX_NUM_CONN)
ntf->num_entries = NCI_MAX_NUM_CONN;
/* update the credits */
for (i = 0; i < ntf->num_entries; i++) {
pr_debug("entry[%d]: conn_id %d, credits %d\n",
i, ntf->conn_entries[i].conn_id,
ntf->conn_entries[i].credits);
if (ntf->conn_entries[i].conn_id == NCI_STATIC_RF_CONN_ID) {
/* found static rf connection */
atomic_add(ntf->conn_entries[i].credits,
&ndev->credits_cnt);
}
}
/* trigger the next tx */
if (!skb_queue_empty(&ndev->tx_q))
queue_work(ndev->tx_wq, &ndev->tx_work);
}
static __u8 *nci_extract_rf_params_nfca_passive_poll(struct nci_dev *ndev,
struct nci_rf_intf_activated_ntf *ntf, __u8 *data)
{
struct rf_tech_specific_params_nfca_poll *nfca_poll;
nfca_poll = &ntf->rf_tech_specific_params.nfca_poll;
nfca_poll->sens_res = __le16_to_cpu(*((__u16 *)data));
data += 2;
nfca_poll->nfcid1_len = *data++;
pr_debug("sens_res 0x%x, nfcid1_len %d\n",
nfca_poll->sens_res, nfca_poll->nfcid1_len);
memcpy(nfca_poll->nfcid1, data, nfca_poll->nfcid1_len);
data += nfca_poll->nfcid1_len;
nfca_poll->sel_res_len = *data++;
if (nfca_poll->sel_res_len != 0)
nfca_poll->sel_res = *data++;
pr_debug("sel_res_len %d, sel_res 0x%x\n",
nfca_poll->sel_res_len,
nfca_poll->sel_res);
return data;
}
static int nci_extract_activation_params_iso_dep(struct nci_dev *ndev,
struct nci_rf_intf_activated_ntf *ntf, __u8 *data)
{
struct activation_params_nfca_poll_iso_dep *nfca_poll;
switch (ntf->activation_rf_tech_and_mode) {
case NCI_NFC_A_PASSIVE_POLL_MODE:
nfca_poll = &ntf->activation_params.nfca_poll_iso_dep;
nfca_poll->rats_res_len = *data++;
if (nfca_poll->rats_res_len > 0) {
memcpy(nfca_poll->rats_res,
data,
nfca_poll->rats_res_len);
}
break;
default:
pr_err("unsupported activation_rf_tech_and_mode 0x%x\n",
ntf->activation_rf_tech_and_mode);
return -EPROTO;
}
return 0;
}
static void nci_target_found(struct nci_dev *ndev,
struct nci_rf_intf_activated_ntf *ntf)
{
struct nfc_target nfc_tgt;
if (ntf->rf_protocol == NCI_RF_PROTOCOL_T2T) /* T2T MifareUL */
nfc_tgt.supported_protocols = NFC_PROTO_MIFARE_MASK;
else if (ntf->rf_protocol == NCI_RF_PROTOCOL_ISO_DEP) /* 4A */
nfc_tgt.supported_protocols = NFC_PROTO_ISO14443_MASK;
else
nfc_tgt.supported_protocols = 0;
nfc_tgt.sens_res = ntf->rf_tech_specific_params.nfca_poll.sens_res;
nfc_tgt.sel_res = ntf->rf_tech_specific_params.nfca_poll.sel_res;
if (!(nfc_tgt.supported_protocols & ndev->poll_prots)) {
pr_debug("the target found does not have the desired protocol\n");
return;
}
pr_debug("new target found, supported_protocols 0x%x\n",
nfc_tgt.supported_protocols);
ndev->target_available_prots = nfc_tgt.supported_protocols;
nfc_targets_found(ndev->nfc_dev, &nfc_tgt, 1);
}
static void nci_rf_intf_activated_ntf_packet(struct nci_dev *ndev,
struct sk_buff *skb)
{
struct nci_rf_intf_activated_ntf ntf;
__u8 *data = skb->data;
int err = 0;
clear_bit(NCI_DISCOVERY, &ndev->flags);
set_bit(NCI_POLL_ACTIVE, &ndev->flags);
ntf.rf_discovery_id = *data++;
ntf.rf_interface_type = *data++;
ntf.rf_protocol = *data++;
ntf.activation_rf_tech_and_mode = *data++;
ntf.rf_tech_specific_params_len = *data++;
pr_debug("rf_discovery_id %d\n", ntf.rf_discovery_id);
pr_debug("rf_interface_type 0x%x\n", ntf.rf_interface_type);
pr_debug("rf_protocol 0x%x\n", ntf.rf_protocol);
pr_debug("activation_rf_tech_and_mode 0x%x\n",
ntf.activation_rf_tech_and_mode);
pr_debug("rf_tech_specific_params_len %d\n",
ntf.rf_tech_specific_params_len);
if (ntf.rf_tech_specific_params_len > 0) {
switch (ntf.activation_rf_tech_and_mode) {
case NCI_NFC_A_PASSIVE_POLL_MODE:
data = nci_extract_rf_params_nfca_passive_poll(ndev,
&ntf, data);
break;
default:
pr_err("unsupported activation_rf_tech_and_mode 0x%x\n",
ntf.activation_rf_tech_and_mode);
return;
}
}
ntf.data_exch_rf_tech_and_mode = *data++;
ntf.data_exch_tx_bit_rate = *data++;
ntf.data_exch_rx_bit_rate = *data++;
ntf.activation_params_len = *data++;
pr_debug("data_exch_rf_tech_and_mode 0x%x\n",
ntf.data_exch_rf_tech_and_mode);
pr_debug("data_exch_tx_bit_rate 0x%x\n",
ntf.data_exch_tx_bit_rate);
pr_debug("data_exch_rx_bit_rate 0x%x\n",
ntf.data_exch_rx_bit_rate);
pr_debug("activation_params_len %d\n",
ntf.activation_params_len);
if (ntf.activation_params_len > 0) {
switch (ntf.rf_interface_type) {
case NCI_RF_INTERFACE_ISO_DEP:
err = nci_extract_activation_params_iso_dep(ndev,
&ntf, data);
break;
case NCI_RF_INTERFACE_FRAME:
/* no activation params */
break;
default:
pr_err("unsupported rf_interface_type 0x%x\n",
ntf.rf_interface_type);
return;
}
}
if (!err)
nci_target_found(ndev, &ntf);
}
static void nci_rf_deactivate_ntf_packet(struct nci_dev *ndev,
struct sk_buff *skb)
{
struct nci_rf_deactivate_ntf *ntf = (void *) skb->data;
pr_debug("entry, type 0x%x, reason 0x%x\n", ntf->type, ntf->reason);
clear_bit(NCI_POLL_ACTIVE, &ndev->flags);
ndev->target_active_prot = 0;
/* drop tx data queue */
skb_queue_purge(&ndev->tx_q);
/* drop partial rx data packet */
if (ndev->rx_data_reassembly) {
kfree_skb(ndev->rx_data_reassembly);
ndev->rx_data_reassembly = 0;
}
/* set the available credits to initial value */
atomic_set(&ndev->credits_cnt, ndev->initial_num_credits);
/* complete the data exchange transaction, if exists */
if (test_bit(NCI_DATA_EXCHANGE, &ndev->flags))
nci_data_exchange_complete(ndev, NULL, -EIO);
}
void nci_ntf_packet(struct nci_dev *ndev, struct sk_buff *skb)
{
__u16 ntf_opcode = nci_opcode(skb->data);
pr_debug("NCI RX: MT=ntf, PBF=%d, GID=0x%x, OID=0x%x, plen=%d\n",
nci_pbf(skb->data),
nci_opcode_gid(ntf_opcode),
nci_opcode_oid(ntf_opcode),
nci_plen(skb->data));
/* strip the nci control header */
skb_pull(skb, NCI_CTRL_HDR_SIZE);
switch (ntf_opcode) {
case NCI_OP_CORE_CONN_CREDITS_NTF:
nci_core_conn_credits_ntf_packet(ndev, skb);
break;
case NCI_OP_RF_INTF_ACTIVATED_NTF:
nci_rf_intf_activated_ntf_packet(ndev, skb);
break;
case NCI_OP_RF_DEACTIVATE_NTF:
nci_rf_deactivate_ntf_packet(ndev, skb);
break;
default:
pr_err("unknown ntf opcode 0x%x\n", ntf_opcode);
break;
}
kfree_skb(skb);
}