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 void nci_core_conn_intf_error_ntf_packet(struct nci_dev *ndev, 75 struct sk_buff *skb) 76 { 77 struct nci_core_intf_error_ntf *ntf = (void *) skb->data; 78 79 ntf->conn_id = nci_conn_id(&ntf->conn_id); 80 81 pr_debug("status 0x%x, conn_id %d\n", ntf->status, ntf->conn_id); 82 83 /* complete the data exchange transaction, if exists */ 84 if (test_bit(NCI_DATA_EXCHANGE, &ndev->flags)) 85 nci_data_exchange_complete(ndev, NULL, -EIO); 86 } 87 88 static __u8 *nci_extract_rf_params_nfca_passive_poll(struct nci_dev *ndev, 89 struct nci_rf_intf_activated_ntf *ntf, __u8 *data) 90 { 91 struct rf_tech_specific_params_nfca_poll *nfca_poll; 92 93 nfca_poll = &ntf->rf_tech_specific_params.nfca_poll; 94 95 nfca_poll->sens_res = __le16_to_cpu(*((__u16 *)data)); 96 data += 2; 97 98 nfca_poll->nfcid1_len = *data++; 99 100 pr_debug("sens_res 0x%x, nfcid1_len %d\n", 101 nfca_poll->sens_res, nfca_poll->nfcid1_len); 102 103 memcpy(nfca_poll->nfcid1, data, nfca_poll->nfcid1_len); 104 data += nfca_poll->nfcid1_len; 105 106 nfca_poll->sel_res_len = *data++; 107 108 if (nfca_poll->sel_res_len != 0) 109 nfca_poll->sel_res = *data++; 110 111 pr_debug("sel_res_len %d, sel_res 0x%x\n", 112 nfca_poll->sel_res_len, 113 nfca_poll->sel_res); 114 115 return data; 116 } 117 118 static int nci_extract_activation_params_iso_dep(struct nci_dev *ndev, 119 struct nci_rf_intf_activated_ntf *ntf, __u8 *data) 120 { 121 struct activation_params_nfca_poll_iso_dep *nfca_poll; 122 123 switch (ntf->activation_rf_tech_and_mode) { 124 case NCI_NFC_A_PASSIVE_POLL_MODE: 125 nfca_poll = &ntf->activation_params.nfca_poll_iso_dep; 126 nfca_poll->rats_res_len = *data++; 127 if (nfca_poll->rats_res_len > 0) { 128 memcpy(nfca_poll->rats_res, 129 data, 130 nfca_poll->rats_res_len); 131 } 132 break; 133 134 default: 135 pr_err("unsupported activation_rf_tech_and_mode 0x%x\n", 136 ntf->activation_rf_tech_and_mode); 137 return -EPROTO; 138 } 139 140 return 0; 141 } 142 143 static void nci_target_found(struct nci_dev *ndev, 144 struct nci_rf_intf_activated_ntf *ntf) 145 { 146 struct nfc_target nfc_tgt; 147 148 if (ntf->rf_protocol == NCI_RF_PROTOCOL_T2T) /* T2T MifareUL */ 149 nfc_tgt.supported_protocols = NFC_PROTO_MIFARE_MASK; 150 else if (ntf->rf_protocol == NCI_RF_PROTOCOL_ISO_DEP) /* 4A */ 151 nfc_tgt.supported_protocols = NFC_PROTO_ISO14443_MASK; 152 else 153 nfc_tgt.supported_protocols = 0; 154 155 nfc_tgt.sens_res = ntf->rf_tech_specific_params.nfca_poll.sens_res; 156 nfc_tgt.sel_res = ntf->rf_tech_specific_params.nfca_poll.sel_res; 157 nfc_tgt.nfcid1_len = ntf->rf_tech_specific_params.nfca_poll.nfcid1_len; 158 if (nfc_tgt.nfcid1_len > 0) { 159 memcpy(nfc_tgt.nfcid1, 160 ntf->rf_tech_specific_params.nfca_poll.nfcid1, 161 nfc_tgt.nfcid1_len); 162 } 163 164 if (!(nfc_tgt.supported_protocols & ndev->poll_prots)) { 165 pr_debug("the target found does not have the desired protocol\n"); 166 return; 167 } 168 169 pr_debug("new target found, supported_protocols 0x%x\n", 170 nfc_tgt.supported_protocols); 171 172 ndev->target_available_prots = nfc_tgt.supported_protocols; 173 ndev->max_data_pkt_payload_size = ntf->max_data_pkt_payload_size; 174 ndev->initial_num_credits = ntf->initial_num_credits; 175 176 /* set the available credits to initial value */ 177 atomic_set(&ndev->credits_cnt, ndev->initial_num_credits); 178 179 nfc_targets_found(ndev->nfc_dev, &nfc_tgt, 1); 180 } 181 182 static void nci_rf_intf_activated_ntf_packet(struct nci_dev *ndev, 183 struct sk_buff *skb) 184 { 185 struct nci_rf_intf_activated_ntf ntf; 186 __u8 *data = skb->data; 187 int err = 0; 188 189 clear_bit(NCI_DISCOVERY, &ndev->flags); 190 set_bit(NCI_POLL_ACTIVE, &ndev->flags); 191 192 ntf.rf_discovery_id = *data++; 193 ntf.rf_interface = *data++; 194 ntf.rf_protocol = *data++; 195 ntf.activation_rf_tech_and_mode = *data++; 196 ntf.max_data_pkt_payload_size = *data++; 197 ntf.initial_num_credits = *data++; 198 ntf.rf_tech_specific_params_len = *data++; 199 200 pr_debug("rf_discovery_id %d\n", ntf.rf_discovery_id); 201 pr_debug("rf_interface 0x%x\n", ntf.rf_interface); 202 pr_debug("rf_protocol 0x%x\n", ntf.rf_protocol); 203 pr_debug("activation_rf_tech_and_mode 0x%x\n", 204 ntf.activation_rf_tech_and_mode); 205 pr_debug("max_data_pkt_payload_size 0x%x\n", 206 ntf.max_data_pkt_payload_size); 207 pr_debug("initial_num_credits 0x%x\n", ntf.initial_num_credits); 208 pr_debug("rf_tech_specific_params_len %d\n", 209 ntf.rf_tech_specific_params_len); 210 211 if (ntf.rf_tech_specific_params_len > 0) { 212 switch (ntf.activation_rf_tech_and_mode) { 213 case NCI_NFC_A_PASSIVE_POLL_MODE: 214 data = nci_extract_rf_params_nfca_passive_poll(ndev, 215 &ntf, data); 216 break; 217 218 default: 219 pr_err("unsupported activation_rf_tech_and_mode 0x%x\n", 220 ntf.activation_rf_tech_and_mode); 221 return; 222 } 223 } 224 225 ntf.data_exch_rf_tech_and_mode = *data++; 226 ntf.data_exch_tx_bit_rate = *data++; 227 ntf.data_exch_rx_bit_rate = *data++; 228 ntf.activation_params_len = *data++; 229 230 pr_debug("data_exch_rf_tech_and_mode 0x%x\n", 231 ntf.data_exch_rf_tech_and_mode); 232 pr_debug("data_exch_tx_bit_rate 0x%x\n", 233 ntf.data_exch_tx_bit_rate); 234 pr_debug("data_exch_rx_bit_rate 0x%x\n", 235 ntf.data_exch_rx_bit_rate); 236 pr_debug("activation_params_len %d\n", 237 ntf.activation_params_len); 238 239 if (ntf.activation_params_len > 0) { 240 switch (ntf.rf_interface) { 241 case NCI_RF_INTERFACE_ISO_DEP: 242 err = nci_extract_activation_params_iso_dep(ndev, 243 &ntf, data); 244 break; 245 246 case NCI_RF_INTERFACE_FRAME: 247 /* no activation params */ 248 break; 249 250 default: 251 pr_err("unsupported rf_interface 0x%x\n", 252 ntf.rf_interface); 253 return; 254 } 255 } 256 257 if (!err) 258 nci_target_found(ndev, &ntf); 259 } 260 261 static void nci_rf_deactivate_ntf_packet(struct nci_dev *ndev, 262 struct sk_buff *skb) 263 { 264 struct nci_rf_deactivate_ntf *ntf = (void *) skb->data; 265 266 pr_debug("entry, type 0x%x, reason 0x%x\n", ntf->type, ntf->reason); 267 268 clear_bit(NCI_POLL_ACTIVE, &ndev->flags); 269 ndev->target_active_prot = 0; 270 271 /* drop tx data queue */ 272 skb_queue_purge(&ndev->tx_q); 273 274 /* drop partial rx data packet */ 275 if (ndev->rx_data_reassembly) { 276 kfree_skb(ndev->rx_data_reassembly); 277 ndev->rx_data_reassembly = 0; 278 } 279 280 /* complete the data exchange transaction, if exists */ 281 if (test_bit(NCI_DATA_EXCHANGE, &ndev->flags)) 282 nci_data_exchange_complete(ndev, NULL, -EIO); 283 } 284 285 void nci_ntf_packet(struct nci_dev *ndev, struct sk_buff *skb) 286 { 287 __u16 ntf_opcode = nci_opcode(skb->data); 288 289 pr_debug("NCI RX: MT=ntf, PBF=%d, GID=0x%x, OID=0x%x, plen=%d\n", 290 nci_pbf(skb->data), 291 nci_opcode_gid(ntf_opcode), 292 nci_opcode_oid(ntf_opcode), 293 nci_plen(skb->data)); 294 295 /* strip the nci control header */ 296 skb_pull(skb, NCI_CTRL_HDR_SIZE); 297 298 switch (ntf_opcode) { 299 case NCI_OP_CORE_CONN_CREDITS_NTF: 300 nci_core_conn_credits_ntf_packet(ndev, skb); 301 break; 302 303 case NCI_OP_CORE_INTF_ERROR_NTF: 304 nci_core_conn_intf_error_ntf_packet(ndev, skb); 305 break; 306 307 case NCI_OP_RF_INTF_ACTIVATED_NTF: 308 nci_rf_intf_activated_ntf_packet(ndev, skb); 309 break; 310 311 case NCI_OP_RF_DEACTIVATE_NTF: 312 nci_rf_deactivate_ntf_packet(ndev, skb); 313 break; 314 315 default: 316 pr_err("unknown ntf opcode 0x%x\n", ntf_opcode); 317 break; 318 } 319 320 kfree_skb(skb); 321 } 322