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 "ath9k.h"
  20 #include "regd_common.h"
  21
  22 /*
  23  * This is a set of common rules used by our world regulatory domains.
  24  * We have 12 world regulatory domains. To save space we consolidate
  25  * the regulatory domains in 5 structures by frequency and change
  26  * the flags on our reg_notifier() on a case by case basis.
  27  */
  28
  29 /* Only these channels all allow active scan on all world regulatory domains */
  30 #define ATH9K_2GHZ_CH01_11      REG_RULE(2412-10, 2462+10, 40, 0, 20, 0)
  31
  32 /* We enable active scan on these a case by case basis by regulatory domain */
  33 #define ATH9K_2GHZ_CH12_13      REG_RULE(2467-10, 2472+10, 40, 0, 20,\
  34                                         NL80211_RRF_PASSIVE_SCAN)
  35 #define ATH9K_2GHZ_CH14         REG_RULE(2484-10, 2484+10, 40, 0, 20,\
  36                                 NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_OFDM)
  37
  38 /* We allow IBSS on these on a case by case basis by regulatory domain */
  39 #define ATH9K_5GHZ_5150_5350    REG_RULE(5150-10, 5350+10, 40, 0, 30,\
  40                                 NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_IBSS)
  41 #define ATH9K_5GHZ_5470_5850    REG_RULE(5470-10, 5850+10, 40, 0, 30,\
  42                                 NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_IBSS)
  43 #define ATH9K_5GHZ_5725_5850    REG_RULE(5725-10, 5850+10, 40, 0, 30,\
  44                                 NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_IBSS)
  45
  46 #define ATH9K_2GHZ_ALL          ATH9K_2GHZ_CH01_11, \
  47                                 ATH9K_2GHZ_CH12_13, \
  48                                 ATH9K_2GHZ_CH14
  49
  50 #define ATH9K_5GHZ_ALL          ATH9K_5GHZ_5150_5350, \
  51                                 ATH9K_5GHZ_5470_5850
  52 /* This one skips what we call "mid band" */
  53 #define ATH9K_5GHZ_NO_MIDBAND   ATH9K_5GHZ_5150_5350, \
  54                                 ATH9K_5GHZ_5725_5850
  55
  56 /* Can be used for:
  57  * 0x60, 0x61, 0x62 */
  58 static const struct ieee80211_regdomain ath9k_world_regdom_60_61_62 = {
  59         .n_reg_rules = 5,
  60         .alpha2 =  "99",
  61         .reg_rules = {
  62                 ATH9K_2GHZ_ALL,
  63                 ATH9K_5GHZ_ALL,
  64         }
  65 };
  66
  67 /* Can be used by 0x63 and 0x65 */
  68 static const struct ieee80211_regdomain ath9k_world_regdom_63_65 = {
  69         .n_reg_rules = 4,
  70         .alpha2 =  "99",
  71         .reg_rules = {
  72                 ATH9K_2GHZ_CH01_11,
  73                 ATH9K_2GHZ_CH12_13,
  74                 ATH9K_5GHZ_NO_MIDBAND,
  75         }
  76 };
  77
  78 /* Can be used by 0x64 only */
  79 static const struct ieee80211_regdomain ath9k_world_regdom_64 = {
  80         .n_reg_rules = 3,
  81         .alpha2 =  "99",
  82         .reg_rules = {
  83                 ATH9K_2GHZ_CH01_11,
  84                 ATH9K_5GHZ_NO_MIDBAND,
  85         }
  86 };
  87
  88 /* Can be used by 0x66 and 0x69 */
  89 static const struct ieee80211_regdomain ath9k_world_regdom_66_69 = {
  90         .n_reg_rules = 3,
  91         .alpha2 =  "99",
  92         .reg_rules = {
  93                 ATH9K_2GHZ_CH01_11,
  94                 ATH9K_5GHZ_ALL,
  95         }
  96 };
  97
  98 /* Can be used by 0x67, 0x6A and 0x68 */
  99 static const struct ieee80211_regdomain ath9k_world_regdom_67_68_6A = {
 100         .n_reg_rules = 4,
 101         .alpha2 =  "99",
 102         .reg_rules = {
 103                 ATH9K_2GHZ_CH01_11,
 104                 ATH9K_2GHZ_CH12_13,
 105                 ATH9K_5GHZ_ALL,
 106         }
 107 };
 108
 109 static inline bool is_wwr_sku(u16 regd)
 110 {
 111         return ((regd & WORLD_SKU_MASK) == WORLD_SKU_PREFIX) ||
 112                 (regd == WORLD);
 113 }
 114
 115 static u16 ath9k_regd_get_eepromRD(struct ath_hw *ah)
 116 {
 117         return ah->regulatory.current_rd & ~WORLDWIDE_ROAMING_FLAG;
 118 }
 119
 120 bool ath9k_is_world_regd(struct ath_hw *ah)
 121 {
 122         return is_wwr_sku(ath9k_regd_get_eepromRD(ah));
 123 }
 124
 125 const struct ieee80211_regdomain *ath9k_default_world_regdomain(void)
 126 {
 127         /* this is the most restrictive */
 128         return &ath9k_world_regdom_64;
 129 }
 130
 131 const struct ieee80211_regdomain *ath9k_world_regdomain(struct ath_hw *ah)
 132 {
 133         switch (ah->regulatory.regpair->regDmnEnum) {
 134         case 0x60:
 135         case 0x61:
 136         case 0x62:
 137                 return &ath9k_world_regdom_60_61_62;
 138         case 0x63:
 139         case 0x65:
 140                 return &ath9k_world_regdom_63_65;
 141         case 0x64:
 142                 return &ath9k_world_regdom_64;
 143         case 0x66:
 144         case 0x69:
 145                 return &ath9k_world_regdom_66_69;
 146         case 0x67:
 147         case 0x68:
 148         case 0x6A:
 149                 return &ath9k_world_regdom_67_68_6A;
 150         default:
 151                 WARN_ON(1);
 152                 return ath9k_default_world_regdomain();
 153         }
 154 }
 155
 156 /* Frequency is one where radar detection is required */
 157 static bool ath9k_is_radar_freq(u16 center_freq)
 158 {
 159         return (center_freq >= 5260 && center_freq <= 5700);
 160 }
 161
 162 /*
 163  * N.B: These exception rules do not apply radar freqs.
 164  *
 165  * - We enable adhoc (or beaconing) if allowed by 11d
 166  * - We enable active scan if the channel is allowed by 11d
 167  * - If no country IE has been processed and a we determine we have
 168  *   received a beacon on a channel we can enable active scan and
 169  *   adhoc (or beaconing).
 170  */
 171 static void ath9k_reg_apply_beaconing_flags(
 172         struct wiphy *wiphy,
 173         enum nl80211_reg_initiator initiator)
 174 {
 175         enum ieee80211_band band;
 176         struct ieee80211_supported_band *sband;
 177         const struct ieee80211_reg_rule *reg_rule;
 178         struct ieee80211_channel *ch;
 179         unsigned int i;
 180         u32 bandwidth = 0;
 181         int r;
 182
 183         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
 184
 185                 if (!wiphy->bands[band])
 186                         continue;
 187
 188                 sband = wiphy->bands[band];
 189
 190                 for (i = 0; i < sband->n_channels; i++) {
 191
 192                         ch = &sband->channels[i];
 193
 194                         if (ath9k_is_radar_freq(ch->center_freq) ||
 195                             (ch->flags & IEEE80211_CHAN_RADAR))
 196                                 continue;
 197
 198                         if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE) {
 199                                 r = freq_reg_info(wiphy, ch->center_freq,
 200                                         &bandwidth, &reg_rule);
 201                                 if (r)
 202                                         continue;
 203                                 /*
 204                                  * If 11d had a rule for this channel ensure
 205                                  * we enable adhoc/beaconing if it allows us to
 206                                  * use it. Note that we would have disabled it
 207                                  * by applying our static world regdomain by
 208                                  * default during init, prior to calling our
 209                                  * regulatory_hint().
 210                                  */
 211                                 if (!(reg_rule->flags &
 212                                     NL80211_RRF_NO_IBSS))
 213                                         ch->flags &=
 214                                           ~IEEE80211_CHAN_NO_IBSS;
 215                                 if (!(reg_rule->flags &
 216                                     NL80211_RRF_PASSIVE_SCAN))
 217                                         ch->flags &=
 218                                           ~IEEE80211_CHAN_PASSIVE_SCAN;
 219                         } else {
 220                                 if (ch->beacon_found)
 221                                         ch->flags &= ~(IEEE80211_CHAN_NO_IBSS |
 222                                           IEEE80211_CHAN_PASSIVE_SCAN);
 223                         }
 224                 }
 225         }
 226
 227 }
 228
 229 /* Allows active scan scan on Ch 12 and 13 */
 230 static void ath9k_reg_apply_active_scan_flags(
 231         struct wiphy *wiphy,
 232         enum nl80211_reg_initiator initiator)
 233 {
 234         struct ieee80211_supported_band *sband;
 235         struct ieee80211_channel *ch;
 236         const struct ieee80211_reg_rule *reg_rule;
 237         u32 bandwidth = 0;
 238         int r;
 239
 240         sband = wiphy->bands[IEEE80211_BAND_2GHZ];
 241
 242         /*
 243          * If no country IE has been received always enable active scan
 244          * on these channels. This is only done for specific regulatory SKUs
 245          */
 246         if (initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
 247                 ch = &sband->channels[11]; /* CH 12 */
 248                 if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
 249                         ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
 250                 ch = &sband->channels[12]; /* CH 13 */
 251                 if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
 252                         ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
 253                 return;
 254         }
 255
 256         /*
 257          * If a country IE has been recieved check its rule for this
 258          * channel first before enabling active scan. The passive scan
 259          * would have been enforced by the initial processing of our
 260          * custom regulatory domain.
 261          */
 262
 263         ch = &sband->channels[11]; /* CH 12 */
 264         r = freq_reg_info(wiphy, ch->center_freq, &bandwidth, &reg_rule);
 265         if (!r) {
 266                 if (!(reg_rule->flags & NL80211_RRF_PASSIVE_SCAN))
 267                         if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
 268                                 ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
 269         }
 270
 271         ch = &sband->channels[12]; /* CH 13 */
 272         r = freq_reg_info(wiphy, ch->center_freq, &bandwidth, &reg_rule);
 273         if (!r) {
 274                 if (!(reg_rule->flags & NL80211_RRF_PASSIVE_SCAN))
 275                         if (ch->flags & IEEE80211_CHAN_PASSIVE_SCAN)
 276                                 ch->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
 277         }
 278 }
 279
 280 /* Always apply Radar/DFS rules on freq range 5260 MHz - 5700 MHz */
 281 void ath9k_reg_apply_radar_flags(struct wiphy *wiphy)
 282 {
 283         struct ieee80211_supported_band *sband;
 284         struct ieee80211_channel *ch;
 285         unsigned int i;
 286
 287         if (!wiphy->bands[IEEE80211_BAND_5GHZ])
 288                 return;
 289
 290         sband = wiphy->bands[IEEE80211_BAND_5GHZ];
 291
 292         for (i = 0; i < sband->n_channels; i++) {
 293                 ch = &sband->channels[i];
 294                 if (!ath9k_is_radar_freq(ch->center_freq))
 295                         continue;
 296                 /* We always enable radar detection/DFS on this
 297                  * frequency range. Additionally we also apply on
 298                  * this frequency range:
 299                  * - If STA mode does not yet have DFS supports disable
 300                  *   active scanning
 301                  * - If adhoc mode does not support DFS yet then
 302                  *   disable adhoc in the frequency.
 303                  * - If AP mode does not yet support radar detection/DFS
 304                  *   do not allow AP mode
 305                  */
 306                 if (!(ch->flags & IEEE80211_CHAN_DISABLED))
 307                         ch->flags |= IEEE80211_CHAN_RADAR |
 308                                      IEEE80211_CHAN_NO_IBSS |
 309                                      IEEE80211_CHAN_PASSIVE_SCAN;
 310         }
 311 }
 312
 313 void ath9k_reg_apply_world_flags(struct wiphy *wiphy,
 314                                  enum nl80211_reg_initiator initiator)
 315 {
 316         struct ieee80211_hw *hw = wiphy_to_ieee80211_hw(wiphy);
 317         struct ath_wiphy *aphy = hw->priv;
 318         struct ath_softc *sc = aphy->sc;
 319         struct ath_hw *ah = sc->sc_ah;
 320
 321         switch (ah->regulatory.regpair->regDmnEnum) {
 322         case 0x60:
 323         case 0x63:
 324         case 0x66:
 325         case 0x67:
 326                 ath9k_reg_apply_beaconing_flags(wiphy, initiator);
 327                 break;
 328         case 0x68:
 329                 ath9k_reg_apply_beaconing_flags(wiphy, initiator);
 330                 ath9k_reg_apply_active_scan_flags(wiphy, initiator);
 331                 break;
 332         }
 333         return;
 334 }
 335
 336 int ath9k_reg_notifier(struct wiphy *wiphy, struct regulatory_request *request)
 337 {
 338         struct ieee80211_hw *hw = wiphy_to_ieee80211_hw(wiphy);
 339         struct ath_wiphy *aphy = hw->priv;
 340         struct ath_softc *sc = aphy->sc;
 341
 342         /* We always apply this */
 343         ath9k_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 (ath9k_is_world_regd(sc->sc_ah))
 352                         ath9k_reg_apply_world_flags(wiphy, request->initiator);
 353                 break;
 354         }
 355
 356         return 0;
 357 }
 358
 359 bool ath9k_regd_is_eeprom_valid(struct ath_hw *ah)
 360 {
 361         u16 rd = ath9k_regd_get_eepromRD(ah);
 362         int i;
 363
 364         if (rd & COUNTRY_ERD_FLAG) {
 365                 /* EEPROM value is a country code */
 366                 u16 cc = rd & ~COUNTRY_ERD_FLAG;
 367                 for (i = 0; i < ARRAY_SIZE(allCountries); i++)
 368                         if (allCountries[i].countryCode == cc)
 369                                 return true;
 370         } else {
 371                 /* EEPROM value is a regpair value */
 372                 for (i = 0; i < ARRAY_SIZE(regDomainPairs); i++)
 373                         if (regDomainPairs[i].regDmnEnum == rd)
 374                                 return true;
 375         }
 376         DPRINTF(ah->ah_sc, ATH_DBG_REGULATORY,
 377                  "invalid regulatory domain/country code 0x%x\n", rd);
 378         return false;
 379 }
 380
 381 /* EEPROM country code to regpair mapping */
 382 static struct country_code_to_enum_rd*
 383 ath9k_regd_find_country(u16 countryCode)
 384 {
 385         int i;
 386
 387         for (i = 0; i < ARRAY_SIZE(allCountries); i++) {
 388                 if (allCountries[i].countryCode == countryCode)
 389                         return &allCountries[i];
 390         }
 391         return NULL;
 392 }
 393
 394 /* EEPROM rd code to regpair mapping */
 395 static struct country_code_to_enum_rd*
 396 ath9k_regd_find_country_by_rd(int regdmn)
 397 {
 398         int i;
 399
 400         for (i = 0; i < ARRAY_SIZE(allCountries); i++) {
 401                 if (allCountries[i].regDmnEnum == regdmn)
 402                         return &allCountries[i];
 403         }
 404         return NULL;
 405 }
 406
 407 /* Returns the map of the EEPROM set RD to a country code */
 408 static u16 ath9k_regd_get_default_country(u16 rd)
 409 {
 410         if (rd & COUNTRY_ERD_FLAG) {
 411                 struct country_code_to_enum_rd *country = NULL;
 412                 u16 cc = rd & ~COUNTRY_ERD_FLAG;
 413
 414                 country = ath9k_regd_find_country(cc);
 415                 if (country != NULL)
 416                         return cc;
 417         }
 418
 419         return CTRY_DEFAULT;
 420 }
 421
 422 static struct reg_dmn_pair_mapping*
 423 ath9k_get_regpair(int regdmn)
 424 {
 425         int i;
 426
 427         if (regdmn == NO_ENUMRD)
 428                 return NULL;
 429         for (i = 0; i < ARRAY_SIZE(regDomainPairs); i++) {
 430                 if (regDomainPairs[i].regDmnEnum == regdmn)
 431                         return &regDomainPairs[i];
 432         }
 433         return NULL;
 434 }
 435
 436 int ath9k_regd_init(struct ath_hw *ah)
 437 {
 438         struct country_code_to_enum_rd *country = NULL;
 439         u16 regdmn;
 440
 441         if (!ath9k_regd_is_eeprom_valid(ah)) {
 442                 DPRINTF(ah->ah_sc, ATH_DBG_REGULATORY,
 443                         "Invalid EEPROM contents\n");
 444                 return -EINVAL;
 445         }
 446
 447         regdmn = ath9k_regd_get_eepromRD(ah);
 448         ah->regulatory.country_code = ath9k_regd_get_default_country(regdmn);
 449
 450         if (ah->regulatory.country_code == CTRY_DEFAULT &&
 451             regdmn == CTRY_DEFAULT)
 452                 ah->regulatory.country_code = CTRY_UNITED_STATES;
 453
 454         if (ah->regulatory.country_code == CTRY_DEFAULT) {
 455                 country = NULL;
 456         } else {
 457                 country = ath9k_regd_find_country(ah->regulatory.country_code);
 458                 if (country == NULL) {
 459                         DPRINTF(ah->ah_sc, ATH_DBG_REGULATORY,
 460                                 "Country is NULL!!!!, cc= %d\n",
 461                                 ah->regulatory.country_code);
 462                         return -EINVAL;
 463                 } else
 464                         regdmn = country->regDmnEnum;
 465         }
 466
 467         ah->regulatory.regpair = ath9k_get_regpair(regdmn);
 468
 469         if (!ah->regulatory.regpair) {
 470                 DPRINTF(ah->ah_sc, ATH_DBG_FATAL,
 471                         "No regulatory domain pair found, cannot continue\n");
 472                 return -EINVAL;
 473         }
 474
 475         if (!country)
 476                 country = ath9k_regd_find_country_by_rd(regdmn);
 477
 478         if (country) {
 479                 ah->regulatory.alpha2[0] = country->isoName[0];
 480                 ah->regulatory.alpha2[1] = country->isoName[1];
 481         } else {
 482                 ah->regulatory.alpha2[0] = '0';
 483                 ah->regulatory.alpha2[1] = '0';
 484         }
 485
 486         DPRINTF(ah->ah_sc, ATH_DBG_REGULATORY,
 487                 "Country alpha2 being used: %c%c\n"
 488                 "Regulatory.Regpair detected: 0x%0x\n",
 489                 ah->regulatory.alpha2[0], ah->regulatory.alpha2[1],
 490                 ah->regulatory.regpair->regDmnEnum);
 491
 492         return 0;
 493 }
 494
 495 u32 ath9k_regd_get_ctl(struct ath_hw *ah, struct ath9k_channel *chan)
 496 {
 497         u32 ctl = NO_CTL;
 498
 499         if (!ah->regulatory.regpair ||
 500             (ah->regulatory.country_code == CTRY_DEFAULT &&
 501              is_wwr_sku(ath9k_regd_get_eepromRD(ah)))) {
 502                 if (IS_CHAN_B(chan))
 503                         ctl = SD_NO_CTL | CTL_11B;
 504                 else if (IS_CHAN_G(chan))
 505                         ctl = SD_NO_CTL | CTL_11G;
 506                 else
 507                         ctl = SD_NO_CTL | CTL_11A;
 508                 return ctl;
 509         }
 510
 511         if (IS_CHAN_B(chan))
 512                 ctl = ah->regulatory.regpair->reg_2ghz_ctl | CTL_11B;
 513         else if (IS_CHAN_G(chan))
 514                 ctl = ah->regulatory.regpair->reg_2ghz_ctl | CTL_11G;
 515         else
 516                 ctl = ah->regulatory.regpair->reg_5ghz_ctl | CTL_11A;
 517
 518         return ctl;
 519 }