drivers/net/wireless/ath/regd.c

   1 /*
   2  * Copyright (c) 2008-2009 Atheros Communications Inc.
   3  *
   4  * Permission to use, copy, modify, and/or distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 #include <linux/kernel.h>
  18 #include <linux/slab.h>
  19 #include <net/cfg80211.h>
  20 #include <net/mac80211.h>
  21 #include "regd.h"
  22 #include "regd_common.h"
  23
  24 /*
  25  * This is a set of common rules used by our world regulatory domains.
  26  * We have 12 world regulatory domains. To save space we consolidate
  27  * the regulatory domains in 5 structures by frequency and change
  28  * the flags on our reg_notifier() on a case by case basis.
  29  */
  30
  31 /* Only these channels all allow active scan on all world regulatory domains */
  32 #define ATH9K_2GHZ_CH01_11      REG_RULE(2412-10, 2462+10, 40, 0, 20, 0)
  33
  34 /* We enable active scan on these a case by case basis by regulatory domain */
  35 #define ATH9K_2GHZ_CH12_13      REG_RULE(2467-10, 2472+10, 40, 0, 20,\
  36                                         NL80211_RRF_PASSIVE_SCAN)
  37 #define ATH9K_2GHZ_CH14         REG_RULE(2484-10, 2484+10, 40, 0, 20,\
  38                                 NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_OFDM)
  39
  40 /* We allow IBSS on these on a case by case basis by regulatory domain */
  41 #define ATH9K_5GHZ_5150_5350    REG_RULE(5150-10, 5350+10, 40, 0, 30,\
  42                                 NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_IBSS)
  43 #define ATH9K_5GHZ_5470_5850    REG_RULE(5470-10, 5850+10, 40, 0, 30,\
  44                                 NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_IBSS)
  45 #define ATH9K_5GHZ_5725_5850    REG_RULE(5725-10, 5850+10, 40, 0, 30,\
  46                                 NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_IBSS)
  47
  48 #define ATH9K_2GHZ_ALL          ATH9K_2GHZ_CH01_11, \
  49                                 ATH9K_2GHZ_CH12_13, \
  50                                 ATH9K_2GHZ_CH14
  51
  52 #define ATH9K_5GHZ_ALL          ATH9K_5GHZ_5150_5350, \
  53                                 ATH9K_5GHZ_5470_5850
  54 /* This one skips what we call "mid band" */
  55 #define ATH9K_5GHZ_NO_MIDBAND   ATH9K_5GHZ_5150_5350, \
  56                                 ATH9K_5GHZ_5725_5850
  57
  58 /* Can be used for:
  59  * 0x60, 0x61, 0x62 */
  60 static const struct ieee80211_regdomain ath_world_regdom_60_61_62 = {
  61         .n_reg_rules = 5,
  62         .alpha2 =  "99",
  63         .reg_rules = {
  64                 ATH9K_2GHZ_ALL,
  65                 ATH9K_5GHZ_ALL,
  66         }
  67 };
  68
  69 /* Can be used by 0x63 and 0x65 */
  70 static const struct ieee80211_regdomain ath_world_regdom_63_65 = {
  71         .n_reg_rules = 4,
  72         .alpha2 =  "99",
  73         .reg_rules = {
  74                 ATH9K_2GHZ_CH01_11,
  75                 ATH9K_2GHZ_CH12_13,
  76                 ATH9K_5GHZ_NO_MIDBAND,
  77         }
  78 };
  79
  80 /* Can be used by 0x64 only */
  81 static const struct ieee80211_regdomain ath_world_regdom_64 = {
  82         .n_reg_rules = 3,
  83         .alpha2 =  "99",
  84         .reg_rules = {
  85                 ATH9K_2GHZ_CH01_11,
  86                 ATH9K_5GHZ_NO_MIDBAND,
  87         }
  88 };
  89
  90 /* Can be used by 0x66 and 0x69 */
  91 static const struct ieee80211_regdomain ath_world_regdom_66_69 = {
  92         .n_reg_rules = 3,
  93         .alpha2 =  "99",
  94         .reg_rules = {
  95                 ATH9K_2GHZ_CH01_11,
  96                 ATH9K_5GHZ_ALL,
  97         }
  98 };
  99
 100 /* Can be used by 0x67, 0x6A and 0x68 */
 101 static const struct ieee80211_regdomain ath_world_regdom_67_68_6A = {
 102         .n_reg_rules = 4,
 103         .alpha2 =  "99",
 104         .reg_rules = {
 105                 ATH9K_2GHZ_CH01_11,
 106                 ATH9K_2GHZ_CH12_13,
 107                 ATH9K_5GHZ_ALL,
 108         }
 109 };
 110
 111 static inline bool is_wwr_sku(u16 regd)
 112 {
 113         return ((regd & WORLD_SKU_MASK) == WORLD_SKU_PREFIX) ||
 114                 (regd == WORLD);
 115 }
 116
 117 static u16 ath_regd_get_eepromRD(struct ath_regulatory *reg)
 118 {
 119         return reg->current_rd & ~WORLDWIDE_ROAMING_FLAG;
 120 }
 121
 122 bool ath_is_world_regd(struct ath_regulatory *reg)
 123 {
 124         return is_wwr_sku(ath_regd_get_eepromRD(reg));
 125 }
 126 EXPORT_SYMBOL(ath_is_world_regd);
 127
 128 static const struct ieee80211_regdomain *ath_default_world_regdomain(void)
 129 {
 130         /* this is the most restrictive */
 131         return &ath_world_regdom_64;
 132 }
 133
 134 static const struct
 135 ieee80211_regdomain *ath_world_regdomain(struct ath_regulatory *reg)
 136 {
 137         switch (reg->regpair->regDmnEnum) {
 138         case 0x60:
 139         case 0x61:
 140         case 0x62:
 141                 return &ath_world_regdom_60_61_62;
 142         case 0x63:
 143         case 0x65:
 144                 return &ath_world_regdom_63_65;
 145         case 0x64:
 146                 return &ath_world_regdom_64;
 147         case 0x66:
 148         case 0x69:
 149                 return &ath_world_regdom_66_69;
 150         case 0x67:
 151         case 0x68:
 152         case 0x6A:
 153                 return &ath_world_regdom_67_68_6A;
 154         default:
 155                 WARN_ON(1);
 156                 return ath_default_world_regdomain();
 157         }
 158 }
 159
 160 /* Frequency is one where radar detection is required */
 161 static bool ath_is_radar_freq(u16 center_freq)
 162 {
 163         return (center_freq >= 5260 && center_freq <= 5700);
 164 }
 165
 166 /*
 167  * N.B: These exception rules do not apply radar freqs.
 168  *
 169  * - We enable adhoc (or beaconing) if allowed by 11d
 170  * - We enable active scan if the channel is allowed by 11d
 171  * - If no country IE has been processed and a we determine we have
 172  *   received a beacon on a channel we can enable active scan and
 173  *   adhoc (or beaconing).
 174  */
 175 static void
 176 ath_reg_apply_beaconing_flags(struct wiphy *wiphy,
 177                               enum nl80211_reg_initiator initiator)
 178 {
 179         enum ieee80211_band band;
 180         struct ieee80211_supported_band *sband;
 181         const struct ieee80211_reg_rule *reg_rule;
 182         struct ieee80211_channel *ch;
 183         unsigned int i;
 184         u32 bandwidth = 0;
 185         int r;
 186
 187         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
 188
 189                 if (!wiphy->bands[band])
 190                         continue;
 191
 192                 sband = wiphy->bands[band];
 193
 194                 for (i = 0; i < sband->n_channels; i++) {
 195
 196                         ch = &sband->channels[i];
 197
 198                         if (ath_is_radar_freq(ch->center_freq) ||
 199                             (ch->flags & IEEE80211_CHAN_RADAR))
 200                                 continue;
 201
 202                         if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE) {
 203                                 r = freq_reg_info(wiphy,
 204                                                   ch->center_freq,
 205                                                   bandwidth,
 206                                                   &reg_rule);
 207                                 if (r)
 208                                         continue;
 209                                 /*
 210                                  * If 11d had a rule for this channel ensure
 211                                  * we enable adhoc/beaconing if it allows us to
 212                                  * use it. Note that we would have disabled it
 213                                  * by applying our static world regdomain by
 214                                  * default during init, prior to calling our
 215                                  * regulatory_hint().
 216                                  */
 217                                 if (!(reg_rule->flags &
 218                                     NL80211_RRF_NO_IBSS))
 219                                         ch->flags &=
 220                                           ~IEEE80211_CHAN_NO_IBSS;
 221                                 if (!(reg_rule->flags &
 222                                     NL80211_RRF_PASSIVE_SCAN))
 223                                         ch->flags &=
 224                                           ~IEEE80211_CHAN_PASSIVE_SCAN;
 225                         } else {
 226                                 if (ch->beacon_found)
 227                                         ch->flags &= ~(IEEE80211_CHAN_NO_IBSS |
 228                                           IEEE80211_CHAN_PASSIVE_SCAN);
 229                         }
 230                 }
 231         }
 232
 233 }
 234
 235 /* Allows active scan scan on Ch 12 and 13 */
 236 static void
 237 ath_reg_apply_active_scan_flags(struct wiphy *wiphy,
 238                                 enum nl80211_reg_initiator initiator)
 239 {
 240         struct ieee80211_supported_band *sband;
 241         struct ieee80211_channel *ch;
 242         const struct ieee80211_reg_rule *reg_rule;
 243         u32 bandwidth = 0;
 244         int r;
 245
 246         sband = wiphy->bands[IEEE80211_BAND_2GHZ];
 247
 248         /*
 249          * If no country IE has been received always enable active scan
 250          * on these channels. This is only done for specific regulatory SKUs
 251          */
 252         if (initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
 253                 ch = &sband->channels[11]; /* CH 12 */
 254                 if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
 255                         ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
 256                 ch = &sband->channels[12]; /* CH 13 */
 257                 if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
 258                         ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
 259                 return;
 260         }
 261
 262         /*
 263          * If a country IE has been recieved check its rule for this
 264          * channel first before enabling active scan. The passive scan
 265          * would have been enforced by the initial processing of our
 266          * custom regulatory domain.
 267          */
 268
 269         ch = &sband->channels[11]; /* CH 12 */
 270         r = freq_reg_info(wiphy, ch->center_freq, bandwidth, &reg_rule);
 271         if (!r) {
 272                 if (!(reg_rule->flags & NL80211_RRF_PASSIVE_SCAN))
 273                         if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
 274                                 ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
 275         }
 276
 277         ch = &sband->channels[12]; /* CH 13 */
 278         r = freq_reg_info(wiphy, ch->center_freq, bandwidth, &reg_rule);
 279         if (!r) {
 280                 if (!(reg_rule->flags & NL80211_RRF_PASSIVE_SCAN))
 281                         if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
 282                                 ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
 283         }
 284 }
 285
 286 /* Always apply Radar/DFS rules on freq range 5260 MHz - 5700 MHz */
 287 static void ath_reg_apply_radar_flags(struct wiphy *wiphy)
 288 {
 289         struct ieee80211_supported_band *sband;
 290         struct ieee80211_channel *ch;
 291         unsigned int i;
 292
 293         if (!wiphy->bands[IEEE80211_BAND_5GHZ])
 294                 return;
 295
 296         sband = wiphy->bands[IEEE80211_BAND_5GHZ];
 297
 298         for (i = 0; i < sband->n_channels; i++) {
 299                 ch = &sband->channels[i];
 300                 if (!ath_is_radar_freq(ch->center_freq))
 301                         continue;
 302                 /* We always enable radar detection/DFS on this
 303                  * frequency range. Additionally we also apply on
 304                  * this frequency range:
 305                  * - If STA mode does not yet have DFS supports disable
 306                  *   active scanning
 307                  * - If adhoc mode does not support DFS yet then
 308                  *   disable adhoc in the frequency.
 309                  * - If AP mode does not yet support radar detection/DFS
 310                  *   do not allow AP mode
 311                  */
 312                 if (!(ch->flags & IEEE80211_CHAN_DISABLED))
 313                         ch->flags |= IEEE80211_CHAN_RADAR |
 314                                      IEEE80211_CHAN_NO_IBSS |
 315                                      IEEE80211_CHAN_PASSIVE_SCAN;
 316         }
 317 }
 318
 319 static void ath_reg_apply_world_flags(struct wiphy *wiphy,
 320                                       enum nl80211_reg_initiator initiator,
 321                                       struct ath_regulatory *reg)
 322 {
 323         switch (reg->regpair->regDmnEnum) {
 324         case 0x60:
 325         case 0x63:
 326         case 0x66:
 327         case 0x67:
 328                 ath_reg_apply_beaconing_flags(wiphy, initiator);
 329                 break;
 330         case 0x68:
 331                 ath_reg_apply_beaconing_flags(wiphy, initiator);
 332                 ath_reg_apply_active_scan_flags(wiphy, initiator);
 333                 break;
 334         }
 335         return;
 336 }
 337
 338 int ath_reg_notifier_apply(struct wiphy *wiphy,
 339                            struct regulatory_request *request,
 340                            struct ath_regulatory *reg)
 341 {
 342         /* We always apply this */
 343         ath_reg_apply_radar_flags(wiphy);
 344
 345         switch (request->initiator) {
 346         case NL80211_REGDOM_SET_BY_DRIVER:
 347         case NL80211_REGDOM_SET_BY_CORE:
 348         case NL80211_REGDOM_SET_BY_USER:
 349                 break;
 350         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
 351                 if (ath_is_world_regd(reg))
 352                         ath_reg_apply_world_flags(wiphy, request->initiator,
 353                                                   reg);
 354                 break;
 355         }
 356
 357         return 0;
 358 }
 359 EXPORT_SYMBOL(ath_reg_notifier_apply);
 360
 361 static bool ath_regd_is_eeprom_valid(struct ath_regulatory *reg)
 362 {
 363          u16 rd = ath_regd_get_eepromRD(reg);
 364         int i;
 365
 366         if (rd & COUNTRY_ERD_FLAG) {
 367                 /* EEPROM value is a country code */
 368                 u16 cc = rd & ~COUNTRY_ERD_FLAG;
 369                 printk(KERN_DEBUG
 370                        "ath: EEPROM indicates we should expect "
 371                         "a country code\n");
 372                 for (i = 0; i < ARRAY_SIZE(allCountries); i++)
 373                         if (allCountries[i].countryCode == cc)
 374                                 return true;
 375         } else {
 376                 /* EEPROM value is a regpair value */
 377                 if (rd != CTRY_DEFAULT)
 378                         printk(KERN_DEBUG "ath: EEPROM indicates we "
 379                                "should expect a direct regpair map\n");
 380                 for (i = 0; i < ARRAY_SIZE(regDomainPairs); i++)
 381                         if (regDomainPairs[i].regDmnEnum == rd)
 382                                 return true;
 383         }
 384         printk(KERN_DEBUG
 385                  "ath: invalid regulatory domain/country code 0x%x\n", rd);
 386         return false;
 387 }
 388
 389 /* EEPROM country code to regpair mapping */
 390 static struct country_code_to_enum_rd*
 391 ath_regd_find_country(u16 countryCode)
 392 {
 393         int i;
 394
 395         for (i = 0; i < ARRAY_SIZE(allCountries); i++) {
 396                 if (allCountries[i].countryCode == countryCode)
 397                         return &allCountries[i];
 398         }
 399         return NULL;
 400 }
 401
 402 /* EEPROM rd code to regpair mapping */
 403 static struct country_code_to_enum_rd*
 404 ath_regd_find_country_by_rd(int regdmn)
 405 {
 406         int i;
 407
 408         for (i = 0; i < ARRAY_SIZE(allCountries); i++) {
 409                 if (allCountries[i].regDmnEnum == regdmn)
 410                         return &allCountries[i];
 411         }
 412         return NULL;
 413 }
 414
 415 /* Returns the map of the EEPROM set RD to a country code */
 416 static u16 ath_regd_get_default_country(u16 rd)
 417 {
 418         if (rd & COUNTRY_ERD_FLAG) {
 419                 struct country_code_to_enum_rd *country = NULL;
 420                 u16 cc = rd & ~COUNTRY_ERD_FLAG;
 421
 422                 country = ath_regd_find_country(cc);
 423                 if (country != NULL)
 424                         return cc;
 425         }
 426
 427         return CTRY_DEFAULT;
 428 }
 429
 430 static struct reg_dmn_pair_mapping*
 431 ath_get_regpair(int regdmn)
 432 {
 433         int i;
 434
 435         if (regdmn == NO_ENUMRD)
 436                 return NULL;
 437         for (i = 0; i < ARRAY_SIZE(regDomainPairs); i++) {
 438                 if (regDomainPairs[i].regDmnEnum == regdmn)
 439                         return &regDomainPairs[i];
 440         }
 441         return NULL;
 442 }
 443
 444 static int
 445 ath_regd_init_wiphy(struct ath_regulatory *reg,
 446                     struct wiphy *wiphy,
 447                     int (*reg_notifier)(struct wiphy *wiphy,
 448                                         struct regulatory_request *request))
 449 {
 450         const struct ieee80211_regdomain *regd;
 451
 452         wiphy->reg_notifier = reg_notifier;
 453         wiphy->flags |= WIPHY_FLAG_STRICT_REGULATORY;
 454
 455         if (ath_is_world_regd(reg)) {
 456                 /*
 457                  * Anything applied here (prior to wiphy registration) gets
 458                  * saved on the wiphy orig_* parameters
 459                  */
 460                 regd = ath_world_regdomain(reg);
 461                 wiphy->flags |= WIPHY_FLAG_CUSTOM_REGULATORY;
 462         } else {
 463                 /*
 464                  * This gets applied in the case of the absense of CRDA,
 465                  * it's our own custom world regulatory domain, similar to
 466                  * cfg80211's but we enable passive scanning.
 467                  */
 468                 regd = ath_default_world_regdomain();
 469         }
 470         wiphy_apply_custom_regulatory(wiphy, regd);
 471         ath_reg_apply_radar_flags(wiphy);
 472         ath_reg_apply_world_flags(wiphy, NL80211_REGDOM_SET_BY_DRIVER, reg);
 473         return 0;
 474 }
 475
 476 /*
 477  * Some users have reported their EEPROM programmed with
 478  * 0x8000 set, this is not a supported regulatory domain
 479  * but since we have more than one user with it we need
 480  * a solution for them. We default to 0x64, which is the
 481  * default Atheros world regulatory domain.
 482  */
 483 static void ath_regd_sanitize(struct ath_regulatory *reg)
 484 {
 485         if (reg->current_rd != COUNTRY_ERD_FLAG)
 486                 return;
 487         printk(KERN_DEBUG "ath: EEPROM regdomain sanitized\n");
 488         reg->current_rd = 0x64;
 489 }
 490
 491 int
 492 ath_regd_init(struct ath_regulatory *reg,
 493               struct wiphy *wiphy,
 494               int (*reg_notifier)(struct wiphy *wiphy,
 495                                   struct regulatory_request *request))
 496 {
 497         struct country_code_to_enum_rd *country = NULL;
 498         u16 regdmn;
 499
 500         if (!reg)
 501                 return -EINVAL;
 502
 503         ath_regd_sanitize(reg);
 504
 505         printk(KERN_DEBUG "ath: EEPROM regdomain: 0x%0x\n", reg->current_rd);
 506
 507         if (!ath_regd_is_eeprom_valid(reg)) {
 508                 printk(KERN_ERR "ath: Invalid EEPROM contents\n");
 509                 return -EINVAL;
 510         }
 511
 512         regdmn = ath_regd_get_eepromRD(reg);
 513         reg->country_code = ath_regd_get_default_country(regdmn);
 514
 515         if (reg->country_code == CTRY_DEFAULT &&
 516             regdmn == CTRY_DEFAULT) {
 517                 printk(KERN_DEBUG "ath: EEPROM indicates default "
 518                        "country code should be used\n");
 519                 reg->country_code = CTRY_UNITED_STATES;
 520         }
 521
 522         if (reg->country_code == CTRY_DEFAULT) {
 523                 country = NULL;
 524         } else {
 525                 printk(KERN_DEBUG "ath: doing EEPROM country->regdmn "
 526                        "map search\n");
 527                 country = ath_regd_find_country(reg->country_code);
 528                 if (country == NULL) {
 529                         printk(KERN_DEBUG
 530                                 "ath: no valid country maps found for "
 531                                 "country code: 0x%0x\n",
 532                                 reg->country_code);
 533                         return -EINVAL;
 534                 } else {
 535                         regdmn = country->regDmnEnum;
 536                         printk(KERN_DEBUG "ath: country maps to "
 537                                "regdmn code: 0x%0x\n",
 538                                regdmn);
 539                 }
 540         }
 541
 542         reg->regpair = ath_get_regpair(regdmn);
 543
 544         if (!reg->regpair) {
 545                 printk(KERN_DEBUG "ath: "
 546                         "No regulatory domain pair found, cannot continue\n");
 547                 return -EINVAL;
 548         }
 549
 550         if (!country)
 551                 country = ath_regd_find_country_by_rd(regdmn);
 552
 553         if (country) {
 554                 reg->alpha2[0] = country->isoName[0];
 555                 reg->alpha2[1] = country->isoName[1];
 556         } else {
 557                 reg->alpha2[0] = '0';
 558                 reg->alpha2[1] = '0';
 559         }
 560
 561         printk(KERN_DEBUG "ath: Country alpha2 being used: %c%c\n",
 562                 reg->alpha2[0], reg->alpha2[1]);
 563         printk(KERN_DEBUG "ath: Regpair used: 0x%0x\n",
 564                 reg->regpair->regDmnEnum);
 565
 566         ath_regd_init_wiphy(reg, wiphy, reg_notifier);
 567         return 0;
 568 }
 569 EXPORT_SYMBOL(ath_regd_init);
 570
 571 u32 ath_regd_get_band_ctl(struct ath_regulatory *reg,
 572                           enum ieee80211_band band)
 573 {
 574         if (!reg->regpair ||
 575             (reg->country_code == CTRY_DEFAULT &&
 576              is_wwr_sku(ath_regd_get_eepromRD(reg)))) {
 577                 return SD_NO_CTL;
 578         }
 579
 580         switch (band) {
 581         case IEEE80211_BAND_2GHZ:
 582                 return reg->regpair->reg_2ghz_ctl;
 583         case IEEE80211_BAND_5GHZ:
 584                 return reg->regpair->reg_5ghz_ctl;
 585         default:
 586                 return NO_CTL;
 587         }
 588 }
 589 EXPORT_SYMBOL(ath_regd_get_band_ctl);