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