Pileus Git - ~andy/linux/blob - net/nfc/hci/command.c

   1 /*
   2  * Copyright (C) 2012  Intel Corporation. All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #define pr_fmt(fmt) "hci: %s: " fmt, __func__
  19
  20 #include <linux/init.h>
  21 #include <linux/kernel.h>
  22 #include <linux/sched.h>
  23 #include <linux/module.h>
  24
  25 #include <net/nfc/hci.h>
  26
  27 #include "hci.h"
  28
  29 static int nfc_hci_execute_cmd_async(struct nfc_hci_dev *hdev, u8 pipe, u8 cmd,
  30                                const u8 *param, size_t param_len,
  31                                data_exchange_cb_t cb, void *cb_context)
  32 {
  33         pr_debug("exec cmd async through pipe=%d, cmd=%d, plen=%zd\n", pipe,
  34                  cmd, param_len);
  35
  36         /* TODO: Define hci cmd execution delay. Should it be the same
  37          * for all commands?
  38          */
  39         return nfc_hci_hcp_message_tx(hdev, pipe, NFC_HCI_HCP_COMMAND, cmd,
  40                                       param, param_len, cb, cb_context, 3000);
  41 }
  42
  43 /*
  44  * HCI command execution completion callback.
  45  * err will be a standard linux error (may be converted from HCI response)
  46  * skb contains the response data and must be disposed, or may be NULL if
  47  * an error occured
  48  */
  49 static void nfc_hci_execute_cb(void *context, struct sk_buff *skb, int err)
  50 {
  51         struct hcp_exec_waiter *hcp_ew = (struct hcp_exec_waiter *)context;
  52
  53         pr_debug("HCI Cmd completed with result=%d\n", err);
  54
  55         hcp_ew->exec_result = err;
  56         if (hcp_ew->exec_result == 0)
  57                 hcp_ew->result_skb = skb;
  58         else
  59                 kfree_skb(skb);
  60         hcp_ew->exec_complete = true;
  61
  62         wake_up(hcp_ew->wq);
  63 }
  64
  65 static int nfc_hci_execute_cmd(struct nfc_hci_dev *hdev, u8 pipe, u8 cmd,
  66                                const u8 *param, size_t param_len,
  67                                struct sk_buff **skb)
  68 {
  69         DECLARE_WAIT_QUEUE_HEAD_ONSTACK(ew_wq);
  70         struct hcp_exec_waiter hcp_ew;
  71         hcp_ew.wq = &ew_wq;
  72         hcp_ew.exec_complete = false;
  73         hcp_ew.result_skb = NULL;
  74
  75         pr_debug("exec cmd sync through pipe=%d, cmd=%d, plen=%zd\n", pipe,
  76                  cmd, param_len);
  77
  78         /* TODO: Define hci cmd execution delay. Should it be the same
  79          * for all commands?
  80          */
  81         hcp_ew.exec_result = nfc_hci_hcp_message_tx(hdev, pipe,
  82                                                     NFC_HCI_HCP_COMMAND, cmd,
  83                                                     param, param_len,
  84                                                     nfc_hci_execute_cb, &hcp_ew,
  85                                                     3000);
  86         if (hcp_ew.exec_result < 0)
  87                 return hcp_ew.exec_result;
  88
  89         wait_event(ew_wq, hcp_ew.exec_complete == true);
  90
  91         if (hcp_ew.exec_result == 0) {
  92                 if (skb)
  93                         *skb = hcp_ew.result_skb;
  94                 else
  95                         kfree_skb(hcp_ew.result_skb);
  96         }
  97
  98         return hcp_ew.exec_result;
  99 }
 100
 101 int nfc_hci_send_event(struct nfc_hci_dev *hdev, u8 gate, u8 event,
 102                        const u8 *param, size_t param_len)
 103 {
 104         u8 pipe;
 105
 106         pr_debug("%d to gate %d\n", event, gate);
 107
 108         pipe = hdev->gate2pipe[gate];
 109         if (pipe == NFC_HCI_INVALID_PIPE)
 110                 return -EADDRNOTAVAIL;
 111
 112         return nfc_hci_hcp_message_tx(hdev, pipe, NFC_HCI_HCP_EVENT, event,
 113                                       param, param_len, NULL, NULL, 0);
 114 }
 115 EXPORT_SYMBOL(nfc_hci_send_event);
 116
 117 int nfc_hci_send_response(struct nfc_hci_dev *hdev, u8 gate, u8 response,
 118                           const u8 *param, size_t param_len)
 119 {
 120         u8 pipe;
 121
 122         pr_debug("\n");
 123
 124         pipe = hdev->gate2pipe[gate];
 125         if (pipe == NFC_HCI_INVALID_PIPE)
 126                 return -EADDRNOTAVAIL;
 127
 128         return nfc_hci_hcp_message_tx(hdev, pipe, NFC_HCI_HCP_RESPONSE,
 129                                       response, param, param_len, NULL, NULL,
 130                                       0);
 131 }
 132 EXPORT_SYMBOL(nfc_hci_send_response);
 133
 134 /*
 135  * Execute an hci command sent to gate.
 136  * skb will contain response data if success. skb can be NULL if you are not
 137  * interested by the response.
 138  */
 139 int nfc_hci_send_cmd(struct nfc_hci_dev *hdev, u8 gate, u8 cmd,
 140                      const u8 *param, size_t param_len, struct sk_buff **skb)
 141 {
 142         u8 pipe;
 143
 144         pr_debug("\n");
 145
 146         pipe = hdev->gate2pipe[gate];
 147         if (pipe == NFC_HCI_INVALID_PIPE)
 148                 return -EADDRNOTAVAIL;
 149
 150         return nfc_hci_execute_cmd(hdev, pipe, cmd, param, param_len, skb);
 151 }
 152 EXPORT_SYMBOL(nfc_hci_send_cmd);
 153
 154 int nfc_hci_send_cmd_async(struct nfc_hci_dev *hdev, u8 gate, u8 cmd,
 155                            const u8 *param, size_t param_len,
 156                            data_exchange_cb_t cb, void *cb_context)
 157 {
 158         u8 pipe;
 159
 160         pr_debug("\n");
 161
 162         pipe = hdev->gate2pipe[gate];
 163         if (pipe == NFC_HCI_INVALID_PIPE)
 164                 return -EADDRNOTAVAIL;
 165
 166         return nfc_hci_execute_cmd_async(hdev, pipe, cmd, param, param_len,
 167                                          cb, cb_context);
 168 }
 169 EXPORT_SYMBOL(nfc_hci_send_cmd_async);
 170
 171 int nfc_hci_set_param(struct nfc_hci_dev *hdev, u8 gate, u8 idx,
 172                       const u8 *param, size_t param_len)
 173 {
 174         int r;
 175         u8 *tmp;
 176
 177         /* TODO ELa: reg idx must be inserted before param, but we don't want
 178          * to ask the caller to do it to keep a simpler API.
 179          * For now, just create a new temporary param buffer. This is far from
 180          * optimal though, and the plan is to modify APIs to pass idx down to
 181          * nfc_hci_hcp_message_tx where the frame is actually built, thereby
 182          * eliminating the need for the temp allocation-copy here.
 183          */
 184
 185         pr_debug("idx=%d to gate %d\n", idx, gate);
 186
 187         tmp = kmalloc(1 + param_len, GFP_KERNEL);
 188         if (tmp == NULL)
 189                 return -ENOMEM;
 190
 191         *tmp = idx;
 192         memcpy(tmp + 1, param, param_len);
 193
 194         r = nfc_hci_send_cmd(hdev, gate, NFC_HCI_ANY_SET_PARAMETER,
 195                              tmp, param_len + 1, NULL);
 196
 197         kfree(tmp);
 198
 199         return r;
 200 }
 201 EXPORT_SYMBOL(nfc_hci_set_param);
 202
 203 int nfc_hci_get_param(struct nfc_hci_dev *hdev, u8 gate, u8 idx,
 204                       struct sk_buff **skb)
 205 {
 206         pr_debug("gate=%d regidx=%d\n", gate, idx);
 207
 208         return nfc_hci_send_cmd(hdev, gate, NFC_HCI_ANY_GET_PARAMETER,
 209                                 &idx, 1, skb);
 210 }
 211 EXPORT_SYMBOL(nfc_hci_get_param);
 212
 213 static int nfc_hci_open_pipe(struct nfc_hci_dev *hdev, u8 pipe)
 214 {
 215         struct sk_buff *skb;
 216         int r;
 217
 218         pr_debug("pipe=%d\n", pipe);
 219
 220         r = nfc_hci_execute_cmd(hdev, pipe, NFC_HCI_ANY_OPEN_PIPE,
 221                                 NULL, 0, &skb);
 222         if (r == 0) {
 223                 /* dest host other than host controller will send
 224                  * number of pipes already open on this gate before
 225                  * execution. The number can be found in skb->data[0]
 226                  */
 227                 kfree_skb(skb);
 228         }
 229
 230         return r;
 231 }
 232
 233 static int nfc_hci_close_pipe(struct nfc_hci_dev *hdev, u8 pipe)
 234 {
 235         pr_debug("\n");
 236
 237         return nfc_hci_execute_cmd(hdev, pipe, NFC_HCI_ANY_CLOSE_PIPE,
 238                                    NULL, 0, NULL);
 239 }
 240
 241 static u8 nfc_hci_create_pipe(struct nfc_hci_dev *hdev, u8 dest_host,
 242                               u8 dest_gate, int *result)
 243 {
 244         struct sk_buff *skb;
 245         struct hci_create_pipe_params params;
 246         struct hci_create_pipe_resp *resp;
 247         u8 pipe;
 248
 249         pr_debug("gate=%d\n", dest_gate);
 250
 251         params.src_gate = NFC_HCI_ADMIN_GATE;
 252         params.dest_host = dest_host;
 253         params.dest_gate = dest_gate;
 254
 255         *result = nfc_hci_execute_cmd(hdev, NFC_HCI_ADMIN_PIPE,
 256                                       NFC_HCI_ADM_CREATE_PIPE,
 257                                       (u8 *) &params, sizeof(params), &skb);
 258         if (*result < 0)
 259                 return NFC_HCI_INVALID_PIPE;
 260
 261         resp = (struct hci_create_pipe_resp *)skb->data;
 262         pipe = resp->pipe;
 263         kfree_skb(skb);
 264
 265         pr_debug("pipe created=%d\n", pipe);
 266
 267         return pipe;
 268 }
 269
 270 static int nfc_hci_delete_pipe(struct nfc_hci_dev *hdev, u8 pipe)
 271 {
 272         pr_debug("\n");
 273
 274         return nfc_hci_execute_cmd(hdev, NFC_HCI_ADMIN_PIPE,
 275                                    NFC_HCI_ADM_DELETE_PIPE, &pipe, 1, NULL);
 276 }
 277
 278 static int nfc_hci_clear_all_pipes(struct nfc_hci_dev *hdev)
 279 {
 280         u8 param[2];
 281         size_t param_len = 2;
 282
 283         /* TODO: Find out what the identity reference data is
 284          * and fill param with it. HCI spec 6.1.3.5 */
 285
 286         pr_debug("\n");
 287
 288         if (test_bit(NFC_HCI_QUIRK_SHORT_CLEAR, &hdev->quirks))
 289                 param_len = 0;
 290
 291         return nfc_hci_execute_cmd(hdev, NFC_HCI_ADMIN_PIPE,
 292                                    NFC_HCI_ADM_CLEAR_ALL_PIPE, param, param_len,
 293                                    NULL);
 294 }
 295
 296 int nfc_hci_disconnect_gate(struct nfc_hci_dev *hdev, u8 gate)
 297 {
 298         int r;
 299         u8 pipe = hdev->gate2pipe[gate];
 300
 301         pr_debug("\n");
 302
 303         if (pipe == NFC_HCI_INVALID_PIPE)
 304                 return -EADDRNOTAVAIL;
 305
 306         r = nfc_hci_close_pipe(hdev, pipe);
 307         if (r < 0)
 308                 return r;
 309
 310         if (pipe != NFC_HCI_LINK_MGMT_PIPE && pipe != NFC_HCI_ADMIN_PIPE) {
 311                 r = nfc_hci_delete_pipe(hdev, pipe);
 312                 if (r < 0)
 313                         return r;
 314         }
 315
 316         hdev->gate2pipe[gate] = NFC_HCI_INVALID_PIPE;
 317
 318         return 0;
 319 }
 320 EXPORT_SYMBOL(nfc_hci_disconnect_gate);
 321
 322 int nfc_hci_disconnect_all_gates(struct nfc_hci_dev *hdev)
 323 {
 324         int r;
 325
 326         pr_debug("\n");
 327
 328         r = nfc_hci_clear_all_pipes(hdev);
 329         if (r < 0)
 330                 return r;
 331
 332         memset(hdev->gate2pipe, NFC_HCI_INVALID_PIPE, sizeof(hdev->gate2pipe));
 333
 334         return 0;
 335 }
 336 EXPORT_SYMBOL(nfc_hci_disconnect_all_gates);
 337
 338 int nfc_hci_connect_gate(struct nfc_hci_dev *hdev, u8 dest_host, u8 dest_gate,
 339                          u8 pipe)
 340 {
 341         bool pipe_created = false;
 342         int r;
 343
 344         pr_debug("\n");
 345
 346         if (hdev->gate2pipe[dest_gate] != NFC_HCI_INVALID_PIPE)
 347                 return -EADDRINUSE;
 348
 349         if (pipe != NFC_HCI_INVALID_PIPE)
 350                 goto open_pipe;
 351
 352         switch (dest_gate) {
 353         case NFC_HCI_LINK_MGMT_GATE:
 354                 pipe = NFC_HCI_LINK_MGMT_PIPE;
 355                 break;
 356         case NFC_HCI_ADMIN_GATE:
 357                 pipe = NFC_HCI_ADMIN_PIPE;
 358                 break;
 359         default:
 360                 pipe = nfc_hci_create_pipe(hdev, dest_host, dest_gate, &r);
 361                 if (pipe == NFC_HCI_INVALID_PIPE)
 362                         return r;
 363                 pipe_created = true;
 364                 break;
 365         }
 366
 367 open_pipe:
 368         r = nfc_hci_open_pipe(hdev, pipe);
 369         if (r < 0) {
 370                 if (pipe_created)
 371                         if (nfc_hci_delete_pipe(hdev, pipe) < 0) {
 372                                 /* TODO: Cannot clean by deleting pipe...
 373                                  * -> inconsistent state */
 374                         }
 375                 return r;
 376         }
 377
 378         hdev->gate2pipe[dest_gate] = pipe;
 379
 380         return 0;
 381 }
 382 EXPORT_SYMBOL(nfc_hci_connect_gate);