drivers/net/wireless/ath9k/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/wireless.h>
  20 #include "ath9k.h"
  21 #include "regd_common.h"
  22
  23 /*
  24  * This is a set of common rules used by our world regulatory domains.
  25  * We have 12 world regulatory domains. To save space we consolidate
  26  * the regulatory domains in 5 structures by frequency and change
  27  * the flags on our reg_notifier() on a case by case basis.
  28  */
  29
  30 /* Only these channels all allow active scan on all world regulatory domains */
  31 #define ATH9K_2GHZ_CH01_11      REG_RULE(2412-10, 2462+10, 40, 0, 20, 0)
  32
  33 /* We enable active scan on these a case by case basis by regulatory domain */
  34 #define ATH9K_2GHZ_CH12_13      REG_RULE(2467-10, 2472+10, 40, 0, 20,\
  35                                         NL80211_RRF_PASSIVE_SCAN)
  36 #define ATH9K_2GHZ_CH14         REG_RULE(2484-10, 2484+10, 40, 0, 20,\
  37                                 NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_OFDM)
  38
  39 /* We allow IBSS on these on a case by case basis by regulatory domain */
  40 #define ATH9K_5GHZ_5150_5350    REG_RULE(5150-10, 5350+10, 40, 0, 30,\
  41                                 NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_IBSS)
  42 #define ATH9K_5GHZ_5470_5850    REG_RULE(5470-10, 5850+10, 40, 0, 30,\
  43                                 NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_IBSS)
  44 #define ATH9K_5GHZ_5725_5850    REG_RULE(5725-10, 5850+10, 40, 0, 30,\
  45                                 NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_IBSS)
  46
  47 #define ATH9K_2GHZ_ALL          ATH9K_2GHZ_CH01_11, \
  48                                 ATH9K_2GHZ_CH12_13, \
  49                                 ATH9K_2GHZ_CH14
  50
  51 #define ATH9K_5GHZ_ALL          ATH9K_5GHZ_5150_5350, \
  52                                 ATH9K_5GHZ_5470_5850
  53 /* This one skips what we call "mid band" */
  54 #define ATH9K_5GHZ_NO_MIDBAND   ATH9K_5GHZ_5150_5350, \
  55                                 ATH9K_5GHZ_5725_5850
  56
  57 /* Can be used for:
  58  * 0x60, 0x61, 0x62 */
  59 static const struct ieee80211_regdomain ath9k_world_regdom_60_61_62 = {
  60         .n_reg_rules = 5,
  61         .alpha2 =  "99",
  62         .reg_rules = {
  63                 ATH9K_2GHZ_ALL,
  64                 ATH9K_5GHZ_ALL,
  65         }
  66 };
  67
  68 /* Can be used by 0x63 and 0x65 */
  69 static const struct ieee80211_regdomain ath9k_world_regdom_63_65 = {
  70         .n_reg_rules = 4,
  71         .alpha2 =  "99",
  72         .reg_rules = {
  73                 ATH9K_2GHZ_CH01_11,
  74                 ATH9K_2GHZ_CH12_13,
  75                 ATH9K_5GHZ_NO_MIDBAND,
  76         }
  77 };
  78
  79 /* Can be used by 0x64 only */
  80 static const struct ieee80211_regdomain ath9k_world_regdom_64 = {
  81         .n_reg_rules = 3,
  82         .alpha2 =  "99",
  83         .reg_rules = {
  84                 ATH9K_2GHZ_CH01_11,
  85                 ATH9K_5GHZ_NO_MIDBAND,
  86         }
  87 };
  88
  89 /* Can be used by 0x66 and 0x69 */
  90 static const struct ieee80211_regdomain ath9k_world_regdom_66_69 = {
  91         .n_reg_rules = 3,
  92         .alpha2 =  "99",
  93         .reg_rules = {
  94                 ATH9K_2GHZ_CH01_11,
  95                 ATH9K_5GHZ_ALL,
  96         }
  97 };
  98
  99 /* Can be used by 0x67, 0x6A and 0x68 */
 100 static const struct ieee80211_regdomain ath9k_world_regdom_67_68_6A = {
 101         .n_reg_rules = 4,
 102         .alpha2 =  "99",
 103         .reg_rules = {
 104                 ATH9K_2GHZ_CH01_11,
 105                 ATH9K_2GHZ_CH12_13,
 106                 ATH9K_5GHZ_ALL,
 107         }
 108 };
 109
 110 static inline bool is_wwr_sku(u16 regd)
 111 {
 112         return ((regd & WORLD_SKU_MASK) == WORLD_SKU_PREFIX) ||
 113                 (regd == WORLD);
 114 }
 115
 116 static u16 ath9k_regd_get_eepromRD(struct ath_hw *ah)
 117 {
 118         return ah->regulatory.current_rd & ~WORLDWIDE_ROAMING_FLAG;
 119 }
 120
 121 bool ath9k_is_world_regd(struct ath_hw *ah)
 122 {
 123         return is_wwr_sku(ath9k_regd_get_eepromRD(ah));
 124 }
 125
 126 const struct ieee80211_regdomain *ath9k_default_world_regdomain(void)
 127 {
 128         /* this is the most restrictive */
 129         return &ath9k_world_regdom_64;
 130 }
 131
 132 const struct ieee80211_regdomain *ath9k_world_regdomain(struct ath_hw *ah)
 133 {
 134         switch (ah->regulatory.regpair->regDmnEnum) {
 135         case 0x60:
 136         case 0x61:
 137         case 0x62:
 138                 return &ath9k_world_regdom_60_61_62;
 139         case 0x63:
 140         case 0x65:
 141                 return &ath9k_world_regdom_63_65;
 142         case 0x64:
 143                 return &ath9k_world_regdom_64;
 144         case 0x66:
 145         case 0x69:
 146                 return &ath9k_world_regdom_66_69;
 147         case 0x67:
 148         case 0x68:
 149         case 0x6A:
 150                 return &ath9k_world_regdom_67_68_6A;
 151         default:
 152                 WARN_ON(1);
 153                 return ath9k_default_world_regdomain();
 154         }
 155 }
 156
 157 /* Frequency is one where radar detection is required */
 158 static bool ath9k_is_radar_freq(u16 center_freq)
 159 {
 160         return (center_freq >= 5260 && center_freq <= 5700);
 161 }
 162
 163 /*
 164  * N.B: These exception rules do not apply radar freqs.
 165  *
 166  * - We enable adhoc (or beaconing) if allowed by 11d
 167  * - We enable active scan if the channel is allowed by 11d
 168  * - If no country IE has been processed and a we determine we have
 169  *   received a beacon on a channel we can enable active scan and
 170  *   adhoc (or beaconing).
 171  */
 172 static void ath9k_reg_apply_beaconing_flags(
 173         struct wiphy *wiphy,
 174         enum nl80211_reg_initiator initiator)
 175 {
 176         enum ieee80211_band band;
 177         struct ieee80211_supported_band *sband;
 178         const struct ieee80211_reg_rule *reg_rule;
 179         struct ieee80211_channel *ch;
 180         unsigned int i;
 181         u32 bandwidth = 0;
 182         int r;
 183
 184         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
 185
 186                 if (!wiphy->bands[band])
 187                         continue;
 188
 189                 sband = wiphy->bands[band];
 190
 191                 for (i = 0; i < sband->n_channels; i++) {
 192
 193                         ch = &sband->channels[i];
 194
 195                         if (ath9k_is_radar_freq(ch->center_freq) ||
 196                             (ch->flags & IEEE80211_CHAN_RADAR))
 197                                 continue;
 198
 199                         if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE) {
 200                                 r = freq_reg_info(wiphy, ch->center_freq,
 201                                         &bandwidth, &reg_rule);
 202                                 if (r)
 203                                         continue;
 204                                 /*
 205                                  * If 11d had a rule for this channel ensure
 206                                  * we enable adhoc/beaconing if it allows us to
 207                                  * use it. Note that we would have disabled it
 208                                  * by applying our static world regdomain by
 209                                  * default during init, prior to calling our
 210                                  * regulatory_hint().
 211                                  */
 212                                 if (!(reg_rule->flags &
 213                                     NL80211_RRF_NO_IBSS))
 214                                         ch->flags &=
 215                                           ~IEEE80211_CHAN_NO_IBSS;
 216                                 if (!(reg_rule->flags &
 217                                     NL80211_RRF_PASSIVE_SCAN))
 218                                         ch->flags &=
 219                                           ~IEEE80211_CHAN_PASSIVE_SCAN;
 220                         } else {
 221                                 if (ch->beacon_found)
 222                                         ch->flags &= ~(IEEE80211_CHAN_NO_IBSS |
 223                                           IEEE80211_CHAN_PASSIVE_SCAN);
 224                         }
 225                 }
 226         }
 227
 228 }
 229
 230 /* Allows active scan scan on Ch 12 and 13 */
 231 static void ath9k_reg_apply_active_scan_flags(
 232         struct wiphy *wiphy,
 233         enum nl80211_reg_initiator initiator)
 234 {
 235         struct ieee80211_supported_band *sband;
 236         struct ieee80211_channel *ch;
 237         const struct ieee80211_reg_rule *reg_rule;
 238         u32 bandwidth = 0;
 239         int r;
 240
 241         sband = wiphy->bands[IEEE80211_BAND_2GHZ];
 242
 243         /*
 244          * If no country IE has been received always enable active scan
 245          * on these channels. This is only done for specific regulatory SKUs
 246          */
 247         if (initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
 248                 ch = &sband->channels[11]; /* CH 12 */
 249                 if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
 250                         ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
 251                 ch = &sband->channels[12]; /* CH 13 */
 252                 if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
 253                         ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
 254                 return;
 255         }
 256
 257         /*
 258          * If a country IE has been recieved check its rule for this
 259          * channel first before enabling active scan. The passive scan
 260          * would have been enforced by the initial processing of our
 261          * custom regulatory domain.
 262          */
 263
 264         ch = &sband->channels[11]; /* CH 12 */
 265         r = freq_reg_info(wiphy, ch->center_freq, &bandwidth, &reg_rule);
 266         if (!r) {
 267                 if (!(reg_rule->flags & NL80211_RRF_PASSIVE_SCAN))
 268                         if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
 269                                 ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
 270         }
 271
 272         ch = &sband->channels[12]; /* CH 13 */
 273         r = freq_reg_info(wiphy, ch->center_freq, &bandwidth, &reg_rule);
 274         if (!r) {
 275                 if (!(reg_rule->flags & NL80211_RRF_PASSIVE_SCAN))
 276                         if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
 277                                 ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
 278         }
 279 }
 280
 281 /* Always apply Radar/DFS rules on freq range 5260 MHz - 5700 MHz */
 282 void ath9k_reg_apply_radar_flags(struct wiphy *wiphy)
 283 {
 284         struct ieee80211_supported_band *sband;
 285         struct ieee80211_channel *ch;
 286         unsigned int i;
 287
 288         if (!wiphy->bands[IEEE80211_BAND_5GHZ])
 289                 return;
 290
 291         sband = wiphy->bands[IEEE80211_BAND_5GHZ];
 292
 293         for (i = 0; i < sband->n_channels; i++) {
 294                 ch = &sband->channels[i];
 295                 if (!ath9k_is_radar_freq(ch->center_freq))
 296                         continue;
 297                 /* We always enable radar detection/DFS on this
 298                  * frequency range. Additionally we also apply on
 299                  * this frequency range:
 300                  * - If STA mode does not yet have DFS supports disable
 301                  *   active scanning
 302                  * - If adhoc mode does not support DFS yet then
 303                  *   disable adhoc in the frequency.
 304                  * - If AP mode does not yet support radar detection/DFS
 305                  *   do not allow AP mode
 306                  */
 307                 if (!(ch->flags & IEEE80211_CHAN_DISABLED))
 308                         ch->flags |= IEEE80211_CHAN_RADAR |
 309                                      IEEE80211_CHAN_NO_IBSS |
 310                                      IEEE80211_CHAN_PASSIVE_SCAN;
 311         }
 312 }
 313
 314 void ath9k_reg_apply_world_flags(struct wiphy *wiphy,
 315                                  enum nl80211_reg_initiator initiator)
 316 {
 317         struct ieee80211_hw *hw = wiphy_to_ieee80211_hw(wiphy);
 318         struct ath_wiphy *aphy = hw->priv;
 319         struct ath_softc *sc = aphy->sc;
 320         struct ath_hw *ah = sc->sc_ah;
 321
 322         switch (ah->regulatory.regpair->regDmnEnum) {
 323         case 0x60:
 324         case 0x63:
 325         case 0x66:
 326         case 0x67:
 327                 ath9k_reg_apply_beaconing_flags(wiphy, initiator);
 328                 break;
 329         case 0x68:
 330                 ath9k_reg_apply_beaconing_flags(wiphy, initiator);
 331                 ath9k_reg_apply_active_scan_flags(wiphy, initiator);
 332                 break;
 333         }
 334         return;
 335 }
 336
 337 int ath9k_reg_notifier(struct wiphy *wiphy, struct regulatory_request *request)
 338 {
 339         struct ieee80211_hw *hw = wiphy_to_ieee80211_hw(wiphy);
 340         struct ath_wiphy *aphy = hw->priv;
 341         struct ath_softc *sc = aphy->sc;
 342
 343         /* We always apply this */
 344         ath9k_reg_apply_radar_flags(wiphy);
 345
 346         switch (request->initiator) {
 347         case NL80211_REGDOM_SET_BY_DRIVER:
 348         case NL80211_REGDOM_SET_BY_CORE:
 349         case NL80211_REGDOM_SET_BY_USER:
 350                 break;
 351         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
 352                 if (ath9k_is_world_regd(sc->sc_ah))
 353                         ath9k_reg_apply_world_flags(wiphy, request->initiator);
 354                 break;
 355         }
 356
 357         return 0;
 358 }
 359
 360 bool ath9k_regd_is_eeprom_valid(struct ath_hw *ah)
 361 {
 362         u16 rd = ath9k_regd_get_eepromRD(ah);
 363         int i;
 364
 365         if (rd & COUNTRY_ERD_FLAG) {
 366                 /* EEPROM value is a country code */
 367                 u16 cc = rd & ~COUNTRY_ERD_FLAG;
 368                 for (i = 0; i < ARRAY_SIZE(allCountries); i++)
 369                         if (allCountries[i].countryCode == cc)
 370                                 return true;
 371         } else {
 372                 /* EEPROM value is a regpair value */
 373                 for (i = 0; i < ARRAY_SIZE(regDomainPairs); i++)
 374                         if (regDomainPairs[i].regDmnEnum == rd)
 375                                 return true;
 376         }
 377         DPRINTF(ah->ah_sc, ATH_DBG_REGULATORY,
 378                  "invalid regulatory domain/country code 0x%x\n", rd);
 379         return false;
 380 }
 381
 382 /* EEPROM country code to regpair mapping */
 383 static struct country_code_to_enum_rd*
 384 ath9k_regd_find_country(u16 countryCode)
 385 {
 386         int i;
 387
 388         for (i = 0; i < ARRAY_SIZE(allCountries); i++) {
 389                 if (allCountries[i].countryCode == countryCode)
 390                         return &allCountries[i];
 391         }
 392         return NULL;
 393 }
 394
 395 /* EEPROM rd code to regpair mapping */
 396 static struct country_code_to_enum_rd*
 397 ath9k_regd_find_country_by_rd(int regdmn)
 398 {
 399         int i;
 400
 401         for (i = 0; i < ARRAY_SIZE(allCountries); i++) {
 402                 if (allCountries[i].regDmnEnum == regdmn)
 403                         return &allCountries[i];
 404         }
 405         return NULL;
 406 }
 407
 408 /* Returns the map of the EEPROM set RD to a country code */
 409 static u16 ath9k_regd_get_default_country(u16 rd)
 410 {
 411         if (rd & COUNTRY_ERD_FLAG) {
 412                 struct country_code_to_enum_rd *country = NULL;
 413                 u16 cc = rd & ~COUNTRY_ERD_FLAG;
 414
 415                 country = ath9k_regd_find_country(cc);
 416                 if (country != NULL)
 417                         return cc;
 418         }
 419
 420         return CTRY_DEFAULT;
 421 }
 422
 423 static struct reg_dmn_pair_mapping*
 424 ath9k_get_regpair(int regdmn)
 425 {
 426         int i;
 427
 428         if (regdmn == NO_ENUMRD)
 429                 return NULL;
 430         for (i = 0; i < ARRAY_SIZE(regDomainPairs); i++) {
 431                 if (regDomainPairs[i].regDmnEnum == regdmn)
 432                         return &regDomainPairs[i];
 433         }
 434         return NULL;
 435 }
 436
 437 int ath9k_regd_init(struct ath_hw *ah)
 438 {
 439         struct country_code_to_enum_rd *country = NULL;
 440         u16 regdmn;
 441
 442         if (!ath9k_regd_is_eeprom_valid(ah)) {
 443                 DPRINTF(ah->ah_sc, ATH_DBG_REGULATORY,
 444                         "Invalid EEPROM contents\n");
 445                 return -EINVAL;
 446         }
 447
 448         regdmn = ath9k_regd_get_eepromRD(ah);
 449         ah->regulatory.country_code = ath9k_regd_get_default_country(regdmn);
 450
 451         if (ah->regulatory.country_code == CTRY_DEFAULT &&
 452             regdmn == CTRY_DEFAULT)
 453                 ah->regulatory.country_code = CTRY_UNITED_STATES;
 454
 455         if (ah->regulatory.country_code == CTRY_DEFAULT) {
 456                 country = NULL;
 457         } else {
 458                 country = ath9k_regd_find_country(ah->regulatory.country_code);
 459                 if (country == NULL) {
 460                         DPRINTF(ah->ah_sc, ATH_DBG_REGULATORY,
 461                                 "Country is NULL!!!!, cc= %d\n",
 462                                 ah->regulatory.country_code);
 463                         return -EINVAL;
 464                 } else
 465                         regdmn = country->regDmnEnum;
 466         }
 467
 468         ah->regulatory.regpair = ath9k_get_regpair(regdmn);
 469
 470         if (!ah->regulatory.regpair) {
 471                 DPRINTF(ah->ah_sc, ATH_DBG_FATAL,
 472                         "No regulatory domain pair found, cannot continue\n");
 473                 return -EINVAL;
 474         }
 475
 476         if (!country)
 477                 country = ath9k_regd_find_country_by_rd(regdmn);
 478
 479         if (country) {
 480                 ah->regulatory.alpha2[0] = country->isoName[0];
 481                 ah->regulatory.alpha2[1] = country->isoName[1];
 482         } else {
 483                 ah->regulatory.alpha2[0] = '0';
 484                 ah->regulatory.alpha2[1] = '0';
 485         }
 486
 487         DPRINTF(ah->ah_sc, ATH_DBG_REGULATORY,
 488                 "Country alpha2 being used: %c%c\n"
 489                 "Regulatory.Regpair detected: 0x%0x\n",
 490                 ah->regulatory.alpha2[0], ah->regulatory.alpha2[1],
 491                 ah->regulatory.regpair->regDmnEnum);
 492
 493         return 0;
 494 }
 495
 496 static
 497 u32 ath9k_regd_get_band_ctl(struct ath_hw *ah, enum ieee80211_band band)
 498 {
 499         if (!ah->regulatory.regpair ||
 500             (ah->regulatory.country_code == CTRY_DEFAULT &&
 501              is_wwr_sku(ath9k_regd_get_eepromRD(ah)))) {
 502                 return SD_NO_CTL;
 503         }
 504
 505         switch (band) {
 506         case IEEE80211_BAND_2GHZ:
 507                 return ah->regulatory.regpair->reg_2ghz_ctl;
 508         case IEEE80211_BAND_5GHZ:
 509                 return ah->regulatory.regpair->reg_5ghz_ctl;
 510         default:
 511                 return NO_CTL;
 512         }
 513
 514         return NO_CTL;
 515 }
 516
 517 u32 ath9k_regd_get_ctl(struct ath_hw *ah, struct ath9k_channel *chan)
 518 {
 519         u32 ctl = ath9k_regd_get_band_ctl(ah, chan->chan->band);
 520
 521         if (IS_CHAN_B(chan))
 522                 ctl |= CTL_11B;
 523         else if (IS_CHAN_G(chan))
 524                 ctl |= CTL_11G;
 525         else
 526                 ctl |= CTL_11A;
 527
 528         return ctl;
 529 }