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 #define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__ 29 30 #include <linux/types.h> 31 #include <linux/interrupt.h> 32 #include <linux/bitops.h> 33 #include <linux/skbuff.h> 34 35 #include "../nfc.h" 36 #include <net/nfc/nci.h> 37 #include <net/nfc/nci_core.h> 38 #include <linux/nfc.h> 39 40 /* Handle NCI Notification packets */ 41 42 static void nci_core_conn_credits_ntf_packet(struct nci_dev *ndev, 43 struct sk_buff *skb) 44 { 45 struct nci_core_conn_credit_ntf *ntf = (void *) skb->data; 46 int i; 47 48 pr_debug("num_entries %d\n", ntf->num_entries); 49 50 if (ntf->num_entries > NCI_MAX_NUM_CONN) 51 ntf->num_entries = NCI_MAX_NUM_CONN; 52 53 /* update the credits */ 54 for (i = 0; i < ntf->num_entries; i++) { 55 ntf->conn_entries[i].conn_id = 56 nci_conn_id(&ntf->conn_entries[i].conn_id); 57 58 pr_debug("entry[%d]: conn_id %d, credits %d\n", 59 i, ntf->conn_entries[i].conn_id, 60 ntf->conn_entries[i].credits); 61 62 if (ntf->conn_entries[i].conn_id == NCI_STATIC_RF_CONN_ID) { 63 /* found static rf connection */ 64 atomic_add(ntf->conn_entries[i].credits, 65 &ndev->credits_cnt); 66 } 67 } 68 69 /* trigger the next tx */ 70 if (!skb_queue_empty(&ndev->tx_q)) 71 queue_work(ndev->tx_wq, &ndev->tx_work); 72 } 73 74 static __u8 *nci_extract_rf_params_nfca_passive_poll(struct nci_dev *ndev, 75 struct nci_rf_intf_activated_ntf *ntf, __u8 *data) 76 { 77 struct rf_tech_specific_params_nfca_poll *nfca_poll; 78 79 nfca_poll = &ntf->rf_tech_specific_params.nfca_poll; 80 81 nfca_poll->sens_res = __le16_to_cpu(*((__u16 *)data)); 82 data += 2; 83 84 nfca_poll->nfcid1_len = *data++; 85 86 pr_debug("sens_res 0x%x, nfcid1_len %d\n", 87 nfca_poll->sens_res, nfca_poll->nfcid1_len); 88 89 memcpy(nfca_poll->nfcid1, data, nfca_poll->nfcid1_len); 90 data += nfca_poll->nfcid1_len; 91 92 nfca_poll->sel_res_len = *data++; 93 94 if (nfca_poll->sel_res_len != 0) 95 nfca_poll->sel_res = *data++; 96 97 pr_debug("sel_res_len %d, sel_res 0x%x\n", 98 nfca_poll->sel_res_len, 99 nfca_poll->sel_res); 100 101 return data; 102 } 103 104 static int nci_extract_activation_params_iso_dep(struct nci_dev *ndev, 105 struct nci_rf_intf_activated_ntf *ntf, __u8 *data) 106 { 107 struct activation_params_nfca_poll_iso_dep *nfca_poll; 108 109 switch (ntf->activation_rf_tech_and_mode) { 110 case NCI_NFC_A_PASSIVE_POLL_MODE: 111 nfca_poll = &ntf->activation_params.nfca_poll_iso_dep; 112 nfca_poll->rats_res_len = *data++; 113 if (nfca_poll->rats_res_len > 0) { 114 memcpy(nfca_poll->rats_res, 115 data, 116 nfca_poll->rats_res_len); 117 } 118 break; 119 120 default: 121 pr_err("unsupported activation_rf_tech_and_mode 0x%x\n", 122 ntf->activation_rf_tech_and_mode); 123 return -EPROTO; 124 } 125 126 return 0; 127 } 128 129 static void nci_target_found(struct nci_dev *ndev, 130 struct nci_rf_intf_activated_ntf *ntf) 131 { 132 struct nfc_target nfc_tgt; 133 134 if (ntf->rf_protocol == NCI_RF_PROTOCOL_T2T) /* T2T MifareUL */ 135 nfc_tgt.supported_protocols = NFC_PROTO_MIFARE_MASK; 136 else if (ntf->rf_protocol == NCI_RF_PROTOCOL_ISO_DEP) /* 4A */ 137 nfc_tgt.supported_protocols = NFC_PROTO_ISO14443_MASK; 138 else 139 nfc_tgt.supported_protocols = 0; 140 141 nfc_tgt.sens_res = ntf->rf_tech_specific_params.nfca_poll.sens_res; 142 nfc_tgt.sel_res = ntf->rf_tech_specific_params.nfca_poll.sel_res; 143 144 if (!(nfc_tgt.supported_protocols & ndev->poll_prots)) { 145 pr_debug("the target found does not have the desired protocol\n"); 146 return; 147 } 148 149 pr_debug("new target found, supported_protocols 0x%x\n", 150 nfc_tgt.supported_protocols); 151 152 ndev->target_available_prots = nfc_tgt.supported_protocols; 153 ndev->max_data_pkt_payload_size = ntf->max_data_pkt_payload_size; 154 ndev->initial_num_credits = ntf->initial_num_credits; 155 156 /* set the available credits to initial value */ 157 atomic_set(&ndev->credits_cnt, ndev->initial_num_credits); 158 159 nfc_targets_found(ndev->nfc_dev, &nfc_tgt, 1); 160 } 161 162 static void nci_rf_intf_activated_ntf_packet(struct nci_dev *ndev, 163 struct sk_buff *skb) 164 { 165 struct nci_rf_intf_activated_ntf ntf; 166 __u8 *data = skb->data; 167 int err = 0; 168 169 clear_bit(NCI_DISCOVERY, &ndev->flags); 170 set_bit(NCI_POLL_ACTIVE, &ndev->flags); 171 172 ntf.rf_discovery_id = *data++; 173 ntf.rf_interface = *data++; 174 ntf.rf_protocol = *data++; 175 ntf.activation_rf_tech_and_mode = *data++; 176 ntf.max_data_pkt_payload_size = *data++; 177 ntf.initial_num_credits = *data++; 178 ntf.rf_tech_specific_params_len = *data++; 179 180 pr_debug("rf_discovery_id %d\n", ntf.rf_discovery_id); 181 pr_debug("rf_interface 0x%x\n", ntf.rf_interface); 182 pr_debug("rf_protocol 0x%x\n", ntf.rf_protocol); 183 pr_debug("activation_rf_tech_and_mode 0x%x\n", 184 ntf.activation_rf_tech_and_mode); 185 pr_debug("max_data_pkt_payload_size 0x%x\n", 186 ntf.max_data_pkt_payload_size); 187 pr_debug("initial_num_credits 0x%x\n", ntf.initial_num_credits); 188 pr_debug("rf_tech_specific_params_len %d\n", 189 ntf.rf_tech_specific_params_len); 190 191 if (ntf.rf_tech_specific_params_len > 0) { 192 switch (ntf.activation_rf_tech_and_mode) { 193 case NCI_NFC_A_PASSIVE_POLL_MODE: 194 data = nci_extract_rf_params_nfca_passive_poll(ndev, 195 &ntf, data); 196 break; 197 198 default: 199 pr_err("unsupported activation_rf_tech_and_mode 0x%x\n", 200 ntf.activation_rf_tech_and_mode); 201 return; 202 } 203 } 204 205 ntf.data_exch_rf_tech_and_mode = *data++; 206 ntf.data_exch_tx_bit_rate = *data++; 207 ntf.data_exch_rx_bit_rate = *data++; 208 ntf.activation_params_len = *data++; 209 210 pr_debug("data_exch_rf_tech_and_mode 0x%x\n", 211 ntf.data_exch_rf_tech_and_mode); 212 pr_debug("data_exch_tx_bit_rate 0x%x\n", 213 ntf.data_exch_tx_bit_rate); 214 pr_debug("data_exch_rx_bit_rate 0x%x\n", 215 ntf.data_exch_rx_bit_rate); 216 pr_debug("activation_params_len %d\n", 217 ntf.activation_params_len); 218 219 if (ntf.activation_params_len > 0) { 220 switch (ntf.rf_interface) { 221 case NCI_RF_INTERFACE_ISO_DEP: 222 err = nci_extract_activation_params_iso_dep(ndev, 223 &ntf, data); 224 break; 225 226 case NCI_RF_INTERFACE_FRAME: 227 /* no activation params */ 228 break; 229 230 default: 231 pr_err("unsupported rf_interface 0x%x\n", 232 ntf.rf_interface); 233 return; 234 } 235 } 236 237 if (!err) 238 nci_target_found(ndev, &ntf); 239 } 240 241 static void nci_rf_deactivate_ntf_packet(struct nci_dev *ndev, 242 struct sk_buff *skb) 243 { 244 struct nci_rf_deactivate_ntf *ntf = (void *) skb->data; 245 246 pr_debug("entry, type 0x%x, reason 0x%x\n", ntf->type, ntf->reason); 247 248 clear_bit(NCI_POLL_ACTIVE, &ndev->flags); 249 ndev->target_active_prot = 0; 250 251 /* drop tx data queue */ 252 skb_queue_purge(&ndev->tx_q); 253 254 /* drop partial rx data packet */ 255 if (ndev->rx_data_reassembly) { 256 kfree_skb(ndev->rx_data_reassembly); 257 ndev->rx_data_reassembly = 0; 258 } 259 260 /* complete the data exchange transaction, if exists */ 261 if (test_bit(NCI_DATA_EXCHANGE, &ndev->flags)) 262 nci_data_exchange_complete(ndev, NULL, -EIO); 263 } 264 265 void nci_ntf_packet(struct nci_dev *ndev, struct sk_buff *skb) 266 { 267 __u16 ntf_opcode = nci_opcode(skb->data); 268 269 pr_debug("NCI RX: MT=ntf, PBF=%d, GID=0x%x, OID=0x%x, plen=%d\n", 270 nci_pbf(skb->data), 271 nci_opcode_gid(ntf_opcode), 272 nci_opcode_oid(ntf_opcode), 273 nci_plen(skb->data)); 274 275 /* strip the nci control header */ 276 skb_pull(skb, NCI_CTRL_HDR_SIZE); 277 278 switch (ntf_opcode) { 279 case NCI_OP_CORE_CONN_CREDITS_NTF: 280 nci_core_conn_credits_ntf_packet(ndev, skb); 281 break; 282 283 case NCI_OP_RF_INTF_ACTIVATED_NTF: 284 nci_rf_intf_activated_ntf_packet(ndev, skb); 285 break; 286 287 case NCI_OP_RF_DEACTIVATE_NTF: 288 nci_rf_deactivate_ntf_packet(ndev, skb); 289 break; 290 291 default: 292 pr_err("unknown ntf opcode 0x%x\n", ntf_opcode); 293 break; 294 } 295 296 kfree_skb(skb); 297 } 298