release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/uwb/beacon.c

   1
   2 #include <linux/kernel.h>
   3 #include <linux/init.h>
   4 #include <linux/module.h>
   5 #include <linux/device.h>
   6 #include <linux/err.h>
   7 #include <linux/kdev_t.h>
   8 #include <linux/slab.h>
   9
  10 #include "uwb-internal.h"
  11
  12 /* Start Beaconing command structure */
  13 struct uwb_rc_cmd_start_beacon {
  14         struct uwb_rccb rccb;
  15         __le16 wBPSTOffset;
  16         u8 bChannelNumber;
  17 } __attribute__((packed));
  18
  19
  20 static int uwb_rc_start_beacon(struct uwb_rc *rc, u16 bpst_offset, u8 channel)
  21 {
  22         int result;
  23         struct uwb_rc_cmd_start_beacon *cmd;
  24         struct uwb_rc_evt_confirm reply;
  25
  26         cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
  27         if (cmd == NULL)
  28                 return -ENOMEM;
  29         cmd->rccb.bCommandType = UWB_RC_CET_GENERAL;
  30         cmd->rccb.wCommand = cpu_to_le16(UWB_RC_CMD_START_BEACON);
  31         cmd->wBPSTOffset = cpu_to_le16(bpst_offset);
  32         cmd->bChannelNumber = channel;
  33         reply.rceb.bEventType = UWB_RC_CET_GENERAL;
  34         reply.rceb.wEvent = UWB_RC_CMD_START_BEACON;
  35         result = uwb_rc_cmd(rc, "START-BEACON", &cmd->rccb, sizeof(*cmd),
  36                             &reply.rceb, sizeof(reply));
  37         if (result < 0)
  38                 goto error_cmd;
  39         if (reply.bResultCode != UWB_RC_RES_SUCCESS) {
  40                 dev_err(&rc->uwb_dev.dev,
  41                         "START-BEACON: command execution failed: %s (%d)\n",
  42                         uwb_rc_strerror(reply.bResultCode), reply.bResultCode);
  43                 result = -EIO;
  44         }
  45 error_cmd:
  46         kfree(cmd);
  47         return result;
  48 }
  49
  50 static int uwb_rc_stop_beacon(struct uwb_rc *rc)
  51 {
  52         int result;
  53         struct uwb_rccb *cmd;
  54         struct uwb_rc_evt_confirm reply;
  55
  56         cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
  57         if (cmd == NULL)
  58                 return -ENOMEM;
  59         cmd->bCommandType = UWB_RC_CET_GENERAL;
  60         cmd->wCommand = cpu_to_le16(UWB_RC_CMD_STOP_BEACON);
  61         reply.rceb.bEventType = UWB_RC_CET_GENERAL;
  62         reply.rceb.wEvent = UWB_RC_CMD_STOP_BEACON;
  63         result = uwb_rc_cmd(rc, "STOP-BEACON", cmd, sizeof(*cmd),
  64                             &reply.rceb, sizeof(reply));
  65         if (result < 0)
  66                 goto error_cmd;
  67         if (reply.bResultCode != UWB_RC_RES_SUCCESS) {
  68                 dev_err(&rc->uwb_dev.dev,
  69                         "STOP-BEACON: command execution failed: %s (%d)\n",
  70                         uwb_rc_strerror(reply.bResultCode), reply.bResultCode);
  71                 result = -EIO;
  72         }
  73 error_cmd:
  74         kfree(cmd);
  75         return result;
  76 }
  77
  78 int uwb_rc_beacon(struct uwb_rc *rc, int channel, unsigned bpst_offset)
  79 {
  80         int result;
  81         struct device *dev = &rc->uwb_dev.dev;
  82
  83         if (channel < 0)
  84                 channel = -1;
  85         if (channel == -1)
  86                 result = uwb_rc_stop_beacon(rc);
  87         else {
  88                 /* channel >= 0...dah */
  89                 result = uwb_rc_start_beacon(rc, bpst_offset, channel);
  90                 if (result < 0)
  91                         return result;
  92                 if (le16_to_cpu(rc->ies->wIELength) > 0) {
  93                         result = uwb_rc_set_ie(rc, rc->ies);
  94                         if (result < 0) {
  95                                 dev_err(dev, "Cannot set new IE on device: "
  96                                         "%d\n", result);
  97                                 result = uwb_rc_stop_beacon(rc);
  98                                 channel = -1;
  99                                 bpst_offset = 0;
 100                         }
 101                 }
 102         }
 103
 104         if (result >= 0)
 105                 rc->beaconing = channel;
 106         return result;
 107 }
 108
 109
 110 void uwb_bce_kfree(struct kref *_bce)
 111 {
 112         struct uwb_beca_e *bce = container_of(_bce, struct uwb_beca_e, refcnt);
 113
 114         kfree(bce->be);
 115         kfree(bce);
 116 }
 117
 118
 119 /* Find a beacon by dev addr in the cache */
 120 static
 121 struct uwb_beca_e *__uwb_beca_find_bydev(struct uwb_rc *rc,
 122                                          const struct uwb_dev_addr *dev_addr)
 123 {
 124         struct uwb_beca_e *bce, *next;
 125         list_for_each_entry_safe(bce, next, &rc->uwb_beca.list, node) {
 126                 if (!memcmp(&bce->dev_addr, dev_addr, sizeof(bce->dev_addr)))
 127                         goto out;
 128         }
 129         bce = NULL;
 130 out:
 131         return bce;
 132 }
 133
 134 /* Find a beacon by dev addr in the cache */
 135 static
 136 struct uwb_beca_e *__uwb_beca_find_bymac(struct uwb_rc *rc,
 137                                          const struct uwb_mac_addr *mac_addr)
 138 {
 139         struct uwb_beca_e *bce, *next;
 140         list_for_each_entry_safe(bce, next, &rc->uwb_beca.list, node) {
 141                 if (!memcmp(bce->mac_addr, mac_addr->data,
 142                             sizeof(struct uwb_mac_addr)))
 143                         goto out;
 144         }
 145         bce = NULL;
 146 out:
 147         return bce;
 148 }
 149
 150 /**
 151  * uwb_dev_get_by_devaddr - get a UWB device with a specific DevAddr
 152  * @rc:      the radio controller that saw the device
 153  * @devaddr: DevAddr of the UWB device to find
 154  *
 155  * There may be more than one matching device (in the case of a
 156  * DevAddr conflict), but only the first one is returned.
 157  */
 158 struct uwb_dev *uwb_dev_get_by_devaddr(struct uwb_rc *rc,
 159                                        const struct uwb_dev_addr *devaddr)
 160 {
 161         struct uwb_dev *found = NULL;
 162         struct uwb_beca_e *bce;
 163
 164         mutex_lock(&rc->uwb_beca.mutex);
 165         bce = __uwb_beca_find_bydev(rc, devaddr);
 166         if (bce)
 167                 found = uwb_dev_try_get(rc, bce->uwb_dev);
 168         mutex_unlock(&rc->uwb_beca.mutex);
 169
 170         return found;
 171 }
 172
 173 /**
 174  * uwb_dev_get_by_macaddr - get a UWB device with a specific EUI-48
 175  * @rc:      the radio controller that saw the device
 176  * @devaddr: EUI-48 of the UWB device to find
 177  */
 178 struct uwb_dev *uwb_dev_get_by_macaddr(struct uwb_rc *rc,
 179                                        const struct uwb_mac_addr *macaddr)
 180 {
 181         struct uwb_dev *found = NULL;
 182         struct uwb_beca_e *bce;
 183
 184         mutex_lock(&rc->uwb_beca.mutex);
 185         bce = __uwb_beca_find_bymac(rc, macaddr);
 186         if (bce)
 187                 found = uwb_dev_try_get(rc, bce->uwb_dev);
 188         mutex_unlock(&rc->uwb_beca.mutex);
 189
 190         return found;
 191 }
 192
 193 /* Initialize a beacon cache entry */
 194 static void uwb_beca_e_init(struct uwb_beca_e *bce)
 195 {
 196         mutex_init(&bce->mutex);
 197         kref_init(&bce->refcnt);
 198         stats_init(&bce->lqe_stats);
 199         stats_init(&bce->rssi_stats);
 200 }
 201
 202 /*
 203  * Add a beacon to the cache
 204  *
 205  * @be:         Beacon event information
 206  * @bf:         Beacon frame (part of b, really)
 207  * @ts_jiffies: Timestamp (in jiffies) when the beacon was received
 208  */
 209 static
 210 struct uwb_beca_e *__uwb_beca_add(struct uwb_rc *rc,
 211                                   struct uwb_rc_evt_beacon *be,
 212                                   struct uwb_beacon_frame *bf,
 213                                   unsigned long ts_jiffies)
 214 {
 215         struct uwb_beca_e *bce;
 216
 217         bce = kzalloc(sizeof(*bce), GFP_KERNEL);
 218         if (bce == NULL)
 219                 return NULL;
 220         uwb_beca_e_init(bce);
 221         bce->ts_jiffies = ts_jiffies;
 222         bce->uwb_dev = NULL;
 223         list_add(&bce->node, &rc->uwb_beca.list);
 224         return bce;
 225 }
 226
 227 /*
 228  * Wipe out beacon entries that became stale
 229  *
 230  * Remove associated devicest too.
 231  */
 232 void uwb_beca_purge(struct uwb_rc *rc)
 233 {
 234         struct uwb_beca_e *bce, *next;
 235         unsigned long expires;
 236
 237         mutex_lock(&rc->uwb_beca.mutex);
 238         list_for_each_entry_safe(bce, next, &rc->uwb_beca.list, node) {
 239                 expires = bce->ts_jiffies + msecs_to_jiffies(beacon_timeout_ms);
 240                 if (time_after(jiffies, expires)) {
 241                         uwbd_dev_offair(bce);
 242                 }
 243         }
 244         mutex_unlock(&rc->uwb_beca.mutex);
 245 }
 246
 247 /* Clean up the whole beacon cache. Called on shutdown */
 248 void uwb_beca_release(struct uwb_rc *rc)
 249 {
 250         struct uwb_beca_e *bce, *next;
 251
 252         mutex_lock(&rc->uwb_beca.mutex);
 253         list_for_each_entry_safe(bce, next, &rc->uwb_beca.list, node) {
 254                 list_del(&bce->node);
 255                 uwb_bce_put(bce);
 256         }
 257         mutex_unlock(&rc->uwb_beca.mutex);
 258 }
 259
 260 static void uwb_beacon_print(struct uwb_rc *rc, struct uwb_rc_evt_beacon *be,
 261                              struct uwb_beacon_frame *bf)
 262 {
 263         char macbuf[UWB_ADDR_STRSIZE];
 264         char devbuf[UWB_ADDR_STRSIZE];
 265         char dstbuf[UWB_ADDR_STRSIZE];
 266
 267         uwb_mac_addr_print(macbuf, sizeof(macbuf), &bf->Device_Identifier);
 268         uwb_dev_addr_print(devbuf, sizeof(devbuf), &bf->hdr.SrcAddr);
 269         uwb_dev_addr_print(dstbuf, sizeof(dstbuf), &bf->hdr.DestAddr);
 270         dev_info(&rc->uwb_dev.dev,
 271                  "BEACON from %s to %s (ch%u offset %u slot %u MAC %s)\n",
 272                  devbuf, dstbuf, be->bChannelNumber, be->wBPSTOffset,
 273                  bf->Beacon_Slot_Number, macbuf);
 274 }
 275
 276 /*
 277  * @bce: beacon cache entry, referenced
 278  */
 279 ssize_t uwb_bce_print_IEs(struct uwb_dev *uwb_dev, struct uwb_beca_e *bce,
 280                           char *buf, size_t size)
 281 {
 282         ssize_t result = 0;
 283         struct uwb_rc_evt_beacon *be;
 284         struct uwb_beacon_frame *bf;
 285         int ies_len;
 286         struct uwb_ie_hdr *ies;
 287
 288         mutex_lock(&bce->mutex);
 289
 290         be = bce->be;
 291         if (be) {
 292                 bf = (struct uwb_beacon_frame *)bce->be->BeaconInfo;
 293                 ies_len = be->wBeaconInfoLength - sizeof(struct uwb_beacon_frame);
 294                 ies = (struct uwb_ie_hdr *)bf->IEData;
 295
 296                 result = uwb_ie_dump_hex(ies, ies_len, buf, size);
 297         }
 298
 299         mutex_unlock(&bce->mutex);
 300
 301         return result;
 302 }
 303
 304 /*
 305  * Verify that the beacon event, frame and IEs are ok
 306  */
 307 static int uwb_verify_beacon(struct uwb_rc *rc, struct uwb_event *evt,
 308                              struct uwb_rc_evt_beacon *be)
 309 {
 310         int result = -EINVAL;
 311         struct uwb_beacon_frame *bf;
 312         struct device *dev = &rc->uwb_dev.dev;
 313
 314         /* Is there enough data to decode a beacon frame? */
 315         if (evt->notif.size < sizeof(*be) + sizeof(*bf)) {
 316                 dev_err(dev, "BEACON event: Not enough data to decode "
 317                         "(%zu vs %zu bytes needed)\n", evt->notif.size,
 318                         sizeof(*be) + sizeof(*bf));
 319                 goto error;
 320         }
 321         result = 0;
 322 error:
 323         return result;
 324 }
 325
 326 /*
 327  * Handle UWB_RC_EVT_BEACON events
 328  *
 329  * We check the beacon cache to see how the received beacon fares. If
 330  * is there already we refresh the timestamp. If not we create a new
 331  * entry.
 332  *
 333  * According to the WHCI and WUSB specs, only one beacon frame is
 334  * allowed per notification block, so we don't bother about scanning
 335  * for more.
 336  */
 337 int uwbd_evt_handle_rc_beacon(struct uwb_event *evt)
 338 {
 339         int result = -EINVAL;
 340         struct uwb_rc *rc;
 341         struct uwb_rc_evt_beacon *be;
 342         struct uwb_beacon_frame *bf;
 343         struct uwb_beca_e *bce;
 344         unsigned long last_ts;
 345
 346         rc = evt->rc;
 347         be = container_of(evt->notif.rceb, struct uwb_rc_evt_beacon, rceb);
 348         result = uwb_verify_beacon(rc, evt, be);
 349         if (result < 0)
 350                 return result;
 351
 352         if (be->bBeaconType == UWB_RC_BEACON_TYPE_OL_ALIEN ||
 353             be->bBeaconType == UWB_RC_BEACON_TYPE_NOL_ALIEN) {
 354                 return -ENOSYS;
 355         }
 356
 357         bf = (struct uwb_beacon_frame *) be->BeaconInfo;
 358
 359         /*
 360          * Drop beacons from devices with a NULL EUI-48 -- they cannot
 361          * be uniquely identified.
 362          *
 363          * It's expected that these will all be WUSB devices and they
 364          * have a WUSB specific connection method so ignoring them
 365          * here shouldn't be a problem.
 366          */
 367         if (uwb_mac_addr_bcast(&bf->Device_Identifier))
 368                 return 0;
 369
 370         mutex_lock(&rc->uwb_beca.mutex);
 371         bce = __uwb_beca_find_bymac(rc, &bf->Device_Identifier);
 372         if (bce == NULL) {
 373                 /* Not in there, a new device is pinging */
 374                 uwb_beacon_print(evt->rc, be, bf);
 375                 bce = __uwb_beca_add(rc, be, bf, evt->ts_jiffies);
 376                 if (bce == NULL) {
 377                         mutex_unlock(&rc->uwb_beca.mutex);
 378                         return -ENOMEM;
 379                 }
 380         }
 381         mutex_unlock(&rc->uwb_beca.mutex);
 382
 383         mutex_lock(&bce->mutex);
 384         /* purge old beacon data */
 385         kfree(bce->be);
 386
 387         last_ts = bce->ts_jiffies;
 388
 389         /* Update commonly used fields */
 390         bce->ts_jiffies = evt->ts_jiffies;
 391         bce->be = be;
 392         bce->dev_addr = bf->hdr.SrcAddr;
 393         bce->mac_addr = &bf->Device_Identifier;
 394         be->wBPSTOffset = le16_to_cpu(be->wBPSTOffset);
 395         be->wBeaconInfoLength = le16_to_cpu(be->wBeaconInfoLength);
 396         stats_add_sample(&bce->lqe_stats, be->bLQI - 7);
 397         stats_add_sample(&bce->rssi_stats, be->bRSSI + 18);
 398
 399         /*
 400          * This might be a beacon from a new device.
 401          */
 402         if (bce->uwb_dev == NULL)
 403                 uwbd_dev_onair(evt->rc, bce);
 404
 405         mutex_unlock(&bce->mutex);
 406
 407         return 1; /* we keep the event data */
 408 }
 409
 410 /*
 411  * Handle UWB_RC_EVT_BEACON_SIZE events
 412  *
 413  * XXXXX
 414  */
 415 int uwbd_evt_handle_rc_beacon_size(struct uwb_event *evt)
 416 {
 417         int result = -EINVAL;
 418         struct device *dev = &evt->rc->uwb_dev.dev;
 419         struct uwb_rc_evt_beacon_size *bs;
 420
 421         /* Is there enough data to decode the event? */
 422         if (evt->notif.size < sizeof(*bs)) {
 423                 dev_err(dev, "BEACON SIZE notification: Not enough data to "
 424                         "decode (%zu vs %zu bytes needed)\n",
 425                         evt->notif.size, sizeof(*bs));
 426                 goto error;
 427         }
 428         bs = container_of(evt->notif.rceb, struct uwb_rc_evt_beacon_size, rceb);
 429         if (0)
 430                 dev_info(dev, "Beacon size changed to %u bytes "
 431                         "(FIXME: action?)\n", le16_to_cpu(bs->wNewBeaconSize));
 432         else {
 433                 /* temporary hack until we do something with this message... */
 434                 static unsigned count;
 435                 if (++count % 1000 == 0)
 436                         dev_info(dev, "Beacon size changed %u times "
 437                                 "(FIXME: action?)\n", count);
 438         }
 439         result = 0;
 440 error:
 441         return result;
 442 }
 443
 444 /**
 445  * uwbd_evt_handle_rc_bp_slot_change - handle a BP_SLOT_CHANGE event
 446  * @evt: the BP_SLOT_CHANGE notification from the radio controller
 447  *
 448  * If the event indicates that no beacon period slots were available
 449  * then radio controller has transitioned to a non-beaconing state.
 450  * Otherwise, simply save the current beacon slot.
 451  */
 452 int uwbd_evt_handle_rc_bp_slot_change(struct uwb_event *evt)
 453 {
 454         struct uwb_rc *rc = evt->rc;
 455         struct device *dev = &rc->uwb_dev.dev;
 456         struct uwb_rc_evt_bp_slot_change *bpsc;
 457
 458         if (evt->notif.size < sizeof(*bpsc)) {
 459                 dev_err(dev, "BP SLOT CHANGE event: Not enough data\n");
 460                 return -EINVAL;
 461         }
 462         bpsc = container_of(evt->notif.rceb, struct uwb_rc_evt_bp_slot_change, rceb);
 463
 464         mutex_lock(&rc->uwb_dev.mutex);
 465         if (uwb_rc_evt_bp_slot_change_no_slot(bpsc)) {
 466                 dev_info(dev, "stopped beaconing: No free slots in BP\n");
 467                 rc->beaconing = -1;
 468         } else
 469                 rc->uwb_dev.beacon_slot = uwb_rc_evt_bp_slot_change_slot_num(bpsc);
 470         mutex_unlock(&rc->uwb_dev.mutex);
 471
 472         return 0;
 473 }
 474
 475 /**
 476  * Handle UWB_RC_EVT_BPOIE_CHANGE events
 477  *
 478  * XXXXX
 479  */
 480 struct uwb_ie_bpo {
 481         struct uwb_ie_hdr hdr;
 482         u8                bp_length;
 483         u8                data[];
 484 } __attribute__((packed));
 485
 486 int uwbd_evt_handle_rc_bpoie_change(struct uwb_event *evt)
 487 {
 488         int result = -EINVAL;
 489         struct device *dev = &evt->rc->uwb_dev.dev;
 490         struct uwb_rc_evt_bpoie_change *bpoiec;
 491         struct uwb_ie_bpo *bpoie;
 492         static unsigned count;
 493         size_t iesize;
 494
 495         /* Is there enough data to decode it? */
 496         if (evt->notif.size < sizeof(*bpoiec)) {
 497                 dev_err(dev, "BPOIEC notification: Not enough data to "
 498                         "decode (%zu vs %zu bytes needed)\n",
 499                         evt->notif.size, sizeof(*bpoiec));
 500                 goto error;
 501         }
 502         bpoiec = container_of(evt->notif.rceb, struct uwb_rc_evt_bpoie_change, rceb);
 503         iesize = le16_to_cpu(bpoiec->wBPOIELength);
 504         if (iesize < sizeof(*bpoie)) {
 505                 dev_err(dev, "BPOIEC notification: Not enough IE data to "
 506                         "decode (%zu vs %zu bytes needed)\n",
 507                         iesize, sizeof(*bpoie));
 508                 goto error;
 509         }
 510         if (++count % 1000 == 0)        /* Lame placeholder */
 511                 dev_info(dev, "BPOIE: %u changes received\n", count);
 512         result = 0;
 513 error:
 514         return result;
 515 }
 516
 517 /*
 518  * Print beaconing state.
 519  */
 520 static ssize_t uwb_rc_beacon_show(struct device *dev,
 521                                   struct device_attribute *attr, char *buf)
 522 {
 523         struct uwb_dev *uwb_dev = to_uwb_dev(dev);
 524         struct uwb_rc *rc = uwb_dev->rc;
 525         ssize_t result;
 526
 527         mutex_lock(&rc->uwb_dev.mutex);
 528         result = sprintf(buf, "%d\n", rc->beaconing);
 529         mutex_unlock(&rc->uwb_dev.mutex);
 530         return result;
 531 }
 532
 533 /*
 534  * Start beaconing on the specified channel, or stop beaconing.
 535  */
 536 static ssize_t uwb_rc_beacon_store(struct device *dev,
 537                                    struct device_attribute *attr,
 538                                    const char *buf, size_t size)
 539 {
 540         struct uwb_dev *uwb_dev = to_uwb_dev(dev);
 541         struct uwb_rc *rc = uwb_dev->rc;
 542         int channel;
 543         ssize_t result = -EINVAL;
 544
 545         result = sscanf(buf, "%d", &channel);
 546         if (result >= 1)
 547                 result = uwb_radio_force_channel(rc, channel);
 548
 549         return result < 0 ? result : size;
 550 }
 551 DEVICE_ATTR(beacon, S_IRUGO | S_IWUSR, uwb_rc_beacon_show, uwb_rc_beacon_store);