net/nfc/nci/ntf.c

   1 /*
   2  *  The NFC Controller Interface is the communication protocol between an
   3  *  NFC Controller (NFCC) and a Device Host (DH).
   4  *
   5  *  Copyright (C) 2011 Texas Instruments, Inc.
   6  *
   7  *  Written by Ilan Elias <ilane@ti.com>
   8  *
   9  *  Acknowledgements:
  10  *  This file is based on hci_event.c, which was written
  11  *  by Maxim Krasnyansky.
  12  *
  13  *  This program is free software; you can redistribute it and/or modify
  14  *  it under the terms of the GNU General Public License version 2
  15  *  as published by the Free Software Foundation
  16  *
  17  *  This program is distributed in the hope that it will be useful,
  18  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  *  GNU General Public License for more details.
  21  *
  22  *  You should have received a copy of the GNU General Public License
  23  *  along with this program; if not, write to the Free Software
  24  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  25  *
  26  */
  27
  28 #include <linux/types.h>
  29 #include <linux/interrupt.h>
  30 #include <linux/bitops.h>
  31 #include <linux/skbuff.h>
  32
  33 #include "../nfc.h"
  34 #include <net/nfc/nci.h>
  35 #include <net/nfc/nci_core.h>
  36 #include <linux/nfc.h>
  37
  38 /* Handle NCI Notification packets */
  39
  40 static void nci_core_conn_credits_ntf_packet(struct nci_dev *ndev,
  41                                                 struct sk_buff *skb)
  42 {
  43         struct nci_core_conn_credit_ntf *ntf = (void *) skb->data;
  44         int i;
  45
  46         nfc_dbg("entry, num_entries %d", ntf->num_entries);
  47
  48         if (ntf->num_entries > NCI_MAX_NUM_CONN)
  49                 ntf->num_entries = NCI_MAX_NUM_CONN;
  50
  51         /* update the credits */
  52         for (i = 0; i < ntf->num_entries; i++) {
  53                 nfc_dbg("entry[%d]: conn_id %d, credits %d", i,
  54                         ntf->conn_entries[i].conn_id,
  55                         ntf->conn_entries[i].credits);
  56
  57                 if (ntf->conn_entries[i].conn_id == ndev->conn_id) {
  58                         /* found static rf connection */
  59                         atomic_add(ntf->conn_entries[i].credits,
  60                                 &ndev->credits_cnt);
  61                 }
  62         }
  63
  64         /* trigger the next tx */
  65         if (!skb_queue_empty(&ndev->tx_q))
  66                 queue_work(ndev->tx_wq, &ndev->tx_work);
  67 }
  68
  69 static void nci_rf_field_info_ntf_packet(struct nci_dev *ndev,
  70                                         struct sk_buff *skb)
  71 {
  72         struct nci_rf_field_info_ntf *ntf = (void *) skb->data;
  73
  74         nfc_dbg("entry, rf_field_status %d", ntf->rf_field_status);
  75 }
  76
  77 static int nci_rf_activate_nfca_passive_poll(struct nci_dev *ndev,
  78                         struct nci_rf_activate_ntf *ntf, __u8 *data)
  79 {
  80         struct rf_tech_specific_params_nfca_poll *nfca_poll;
  81         struct activation_params_nfca_poll_iso_dep *nfca_poll_iso_dep;
  82
  83         nfca_poll = &ntf->rf_tech_specific_params.nfca_poll;
  84         nfca_poll_iso_dep = &ntf->activation_params.nfca_poll_iso_dep;
  85
  86         nfca_poll->sens_res = __le16_to_cpu(*((__u16 *)data));
  87         data += 2;
  88
  89         nfca_poll->nfcid1_len = *data++;
  90
  91         nfc_dbg("sens_res 0x%x, nfcid1_len %d",
  92                 nfca_poll->sens_res,
  93                 nfca_poll->nfcid1_len);
  94
  95         memcpy(nfca_poll->nfcid1, data, nfca_poll->nfcid1_len);
  96         data += nfca_poll->nfcid1_len;
  97
  98         nfca_poll->sel_res_len = *data++;
  99
 100         if (nfca_poll->sel_res_len != 0)
 101                 nfca_poll->sel_res = *data++;
 102
 103         ntf->rf_interface_type = *data++;
 104         ntf->activation_params_len = *data++;
 105
 106         nfc_dbg("sel_res_len %d, sel_res 0x%x, rf_interface_type %d, activation_params_len %d",
 107                 nfca_poll->sel_res_len,
 108                 nfca_poll->sel_res,
 109                 ntf->rf_interface_type,
 110                 ntf->activation_params_len);
 111
 112         switch (ntf->rf_interface_type) {
 113         case NCI_RF_INTERFACE_ISO_DEP:
 114                 nfca_poll_iso_dep->rats_res_len = *data++;
 115                 if (nfca_poll_iso_dep->rats_res_len > 0) {
 116                         memcpy(nfca_poll_iso_dep->rats_res,
 117                                 data,
 118                                 nfca_poll_iso_dep->rats_res_len);
 119                 }
 120                 break;
 121
 122         case NCI_RF_INTERFACE_FRAME:
 123                 /* no activation params */
 124                 break;
 125
 126         default:
 127                 nfc_err("unsupported rf_interface_type 0x%x",
 128                         ntf->rf_interface_type);
 129                 return -EPROTO;
 130         }
 131
 132         return 0;
 133 }
 134
 135 static void nci_target_found(struct nci_dev *ndev,
 136                                 struct nci_rf_activate_ntf *ntf)
 137 {
 138         struct nfc_target nfc_tgt;
 139
 140         if (ntf->rf_protocol == NCI_RF_PROTOCOL_T2T)    /* T2T MifareUL */
 141                 nfc_tgt.supported_protocols = NFC_PROTO_MIFARE_MASK;
 142         else if (ntf->rf_protocol == NCI_RF_PROTOCOL_ISO_DEP)   /* 4A */
 143                 nfc_tgt.supported_protocols = NFC_PROTO_ISO14443_MASK;
 144
 145         nfc_tgt.sens_res = ntf->rf_tech_specific_params.nfca_poll.sens_res;
 146         nfc_tgt.sel_res = ntf->rf_tech_specific_params.nfca_poll.sel_res;
 147
 148         if (!(nfc_tgt.supported_protocols & ndev->poll_prots)) {
 149                 nfc_dbg("the target found does not have the desired protocol");
 150                 return;
 151         }
 152
 153         nfc_dbg("new target found,  supported_protocols 0x%x",
 154                 nfc_tgt.supported_protocols);
 155
 156         ndev->target_available_prots = nfc_tgt.supported_protocols;
 157
 158         nfc_targets_found(ndev->nfc_dev, &nfc_tgt, 1);
 159 }
 160
 161 static void nci_rf_activate_ntf_packet(struct nci_dev *ndev,
 162                                         struct sk_buff *skb)
 163 {
 164         struct nci_rf_activate_ntf ntf;
 165         __u8 *data = skb->data;
 166         int rc = -1;
 167
 168         clear_bit(NCI_DISCOVERY, &ndev->flags);
 169         set_bit(NCI_POLL_ACTIVE, &ndev->flags);
 170
 171         ntf.target_handle = *data++;
 172         ntf.rf_protocol = *data++;
 173         ntf.rf_tech_and_mode = *data++;
 174         ntf.rf_tech_specific_params_len = *data++;
 175
 176         nfc_dbg("target_handle %d, rf_protocol 0x%x, rf_tech_and_mode 0x%x, rf_tech_specific_params_len %d",
 177                 ntf.target_handle,
 178                 ntf.rf_protocol,
 179                 ntf.rf_tech_and_mode,
 180                 ntf.rf_tech_specific_params_len);
 181
 182         switch (ntf.rf_tech_and_mode) {
 183         case NCI_NFC_A_PASSIVE_POLL_MODE:
 184                 rc = nci_rf_activate_nfca_passive_poll(ndev, &ntf,
 185                         data);
 186                 break;
 187
 188         default:
 189                 nfc_err("unsupported rf_tech_and_mode 0x%x",
 190                         ntf.rf_tech_and_mode);
 191                 return;
 192         }
 193
 194         if (!rc)
 195                 nci_target_found(ndev, &ntf);
 196 }
 197
 198 static void nci_rf_deactivate_ntf_packet(struct nci_dev *ndev,
 199                                         struct sk_buff *skb)
 200 {
 201         __u8 type = skb->data[0];
 202
 203         nfc_dbg("entry, type 0x%x", type);
 204
 205         clear_bit(NCI_POLL_ACTIVE, &ndev->flags);
 206         ndev->target_active_prot = 0;
 207
 208         /* drop tx data queue */
 209         skb_queue_purge(&ndev->tx_q);
 210
 211         /* drop partial rx data packet */
 212         if (ndev->rx_data_reassembly) {
 213                 kfree_skb(ndev->rx_data_reassembly);
 214                 ndev->rx_data_reassembly = 0;
 215         }
 216
 217         /* complete the data exchange transaction, if exists */
 218         if (test_bit(NCI_DATA_EXCHANGE, &ndev->flags))
 219                 nci_data_exchange_complete(ndev, NULL, -EIO);
 220 }
 221
 222 void nci_ntf_packet(struct nci_dev *ndev, struct sk_buff *skb)
 223 {
 224         __u16 ntf_opcode = nci_opcode(skb->data);
 225
 226         nfc_dbg("NCI RX: MT=ntf, PBF=%d, GID=0x%x, OID=0x%x, plen=%d",
 227                         nci_pbf(skb->data),
 228                         nci_opcode_gid(ntf_opcode),
 229                         nci_opcode_oid(ntf_opcode),
 230                         nci_plen(skb->data));
 231
 232         /* strip the nci control header */
 233         skb_pull(skb, NCI_CTRL_HDR_SIZE);
 234
 235         switch (ntf_opcode) {
 236         case NCI_OP_CORE_CONN_CREDITS_NTF:
 237                 nci_core_conn_credits_ntf_packet(ndev, skb);
 238                 break;
 239
 240         case NCI_OP_RF_FIELD_INFO_NTF:
 241                 nci_rf_field_info_ntf_packet(ndev, skb);
 242                 break;
 243
 244         case NCI_OP_RF_ACTIVATE_NTF:
 245                 nci_rf_activate_ntf_packet(ndev, skb);
 246                 break;
 247
 248         case NCI_OP_RF_DEACTIVATE_NTF:
 249                 nci_rf_deactivate_ntf_packet(ndev, skb);
 250                 break;
 251
 252         default:
 253                 nfc_err("unknown ntf opcode 0x%x", ntf_opcode);
 254                 break;
 255         }
 256
 257         kfree_skb(skb);
 258 }