drivers/net/wireless/iwlwifi/iwl-eeprom.c

   1 /******************************************************************************
   2  *
   3  * This file is provided under a dual BSD/GPLv2 license.  When using or
   4  * redistributing this file, you may do so under either license.
   5  *
   6  * GPL LICENSE SUMMARY
   7  *
   8  * Copyright(c) 2008 Intel Corporation. All rights reserved.
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of version 2 of the GNU General Public License as
  12  * published by the Free Software Foundation.
  13  *
  14  * This program is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
  22  * USA
  23  *
  24  * The full GNU General Public License is included in this distribution
  25  * in the file called LICENSE.GPL.
  26  *
  27  * Contact Information:
  28  * Tomas Winkler <tomas.winkler@intel.com>
  29  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  30  *
  31  * BSD LICENSE
  32  *
  33  * Copyright(c) 2005 - 2008 Intel Corporation. All rights reserved.
  34  * All rights reserved.
  35  *
  36  * Redistribution and use in source and binary forms, with or without
  37  * modification, are permitted provided that the following conditions
  38  * are met:
  39  *
  40  *  * Redistributions of source code must retain the above copyright
  41  *    notice, this list of conditions and the following disclaimer.
  42  *  * Redistributions in binary form must reproduce the above copyright
  43  *    notice, this list of conditions and the following disclaimer in
  44  *    the documentation and/or other materials provided with the
  45  *    distribution.
  46  *  * Neither the name Intel Corporation nor the names of its
  47  *    contributors may be used to endorse or promote products derived
  48  *    from this software without specific prior written permission.
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  51  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  52  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  53  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  54  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  55  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  56  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  57  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  58  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  59  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  60  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  61  *****************************************************************************/
  62
  63
  64 #include <linux/kernel.h>
  65 #include <linux/module.h>
  66 #include <linux/version.h>
  67 #include <linux/init.h>
  68
  69 #include <net/mac80211.h>
  70
  71 #include "iwl-4965-commands.h"
  72 #include "iwl-4965.h"
  73 #include "iwl-core.h"
  74 #include "iwl-debug.h"
  75 #include "iwl-eeprom.h"
  76 #include "iwl-io.h"
  77
  78 /************************** EEPROM BANDS ****************************
  79  *
  80  * The iwl_eeprom_band definitions below provide the mapping from the
  81  * EEPROM contents to the specific channel number supported for each
  82  * band.
  83  *
  84  * For example, iwl_priv->eeprom.band_3_channels[4] from the band_3
  85  * definition below maps to physical channel 42 in the 5.2GHz spectrum.
  86  * The specific geography and calibration information for that channel
  87  * is contained in the eeprom map itself.
  88  *
  89  * During init, we copy the eeprom information and channel map
  90  * information into priv->channel_info_24/52 and priv->channel_map_24/52
  91  *
  92  * channel_map_24/52 provides the index in the channel_info array for a
  93  * given channel.  We have to have two separate maps as there is channel
  94  * overlap with the 2.4GHz and 5.2GHz spectrum as seen in band_1 and
  95  * band_2
  96  *
  97  * A value of 0xff stored in the channel_map indicates that the channel
  98  * is not supported by the hardware at all.
  99  *
 100  * A value of 0xfe in the channel_map indicates that the channel is not
 101  * valid for Tx with the current hardware.  This means that
 102  * while the system can tune and receive on a given channel, it may not
 103  * be able to associate or transmit any frames on that
 104  * channel.  There is no corresponding channel information for that
 105  * entry.
 106  *
 107  *********************************************************************/
 108
 109 /* 2.4 GHz */
 110 const u8 iwl_eeprom_band_1[14] = {
 111         1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14
 112 };
 113
 114 /* 5.2 GHz bands */
 115 static const u8 iwl_eeprom_band_2[] = { /* 4915-5080MHz */
 116         183, 184, 185, 187, 188, 189, 192, 196, 7, 8, 11, 12, 16
 117 };
 118
 119 static const u8 iwl_eeprom_band_3[] = { /* 5170-5320MHz */
 120         34, 36, 38, 40, 42, 44, 46, 48, 52, 56, 60, 64
 121 };
 122
 123 static const u8 iwl_eeprom_band_4[] = { /* 5500-5700MHz */
 124         100, 104, 108, 112, 116, 120, 124, 128, 132, 136, 140
 125 };
 126
 127 static const u8 iwl_eeprom_band_5[] = { /* 5725-5825MHz */
 128         145, 149, 153, 157, 161, 165
 129 };
 130
 131 static const u8 iwl_eeprom_band_6[] = {       /* 2.4 FAT channel */
 132         1, 2, 3, 4, 5, 6, 7
 133 };
 134
 135 static const u8 iwl_eeprom_band_7[] = {       /* 5.2 FAT channel */
 136         36, 44, 52, 60, 100, 108, 116, 124, 132, 149, 157
 137 };
 138
 139 /******************************************************************************
 140  *
 141  * EEPROM related functions
 142  *
 143 ******************************************************************************/
 144
 145 int iwlcore_eeprom_verify_signature(struct iwl_priv *priv)
 146 {
 147         u32 gp = iwl_read32(priv, CSR_EEPROM_GP);
 148         if ((gp & CSR_EEPROM_GP_VALID_MSK) == CSR_EEPROM_GP_BAD_SIGNATURE) {
 149                 IWL_ERROR("EEPROM not found, EEPROM_GP=0x%08x", gp);
 150                 return -ENOENT;
 151         }
 152         return 0;
 153 }
 154 EXPORT_SYMBOL(iwlcore_eeprom_verify_signature);
 155
 156 /*
 157  * The device's EEPROM semaphore prevents conflicts between driver and uCode
 158  * when accessing the EEPROM; each access is a series of pulses to/from the
 159  * EEPROM chip, not a single event, so even reads could conflict if they
 160  * weren't arbitrated by the semaphore.
 161  */
 162 int iwlcore_eeprom_acquire_semaphore(struct iwl_priv *priv)
 163 {
 164         u16 count;
 165         int ret;
 166
 167         for (count = 0; count < EEPROM_SEM_RETRY_LIMIT; count++) {
 168                 /* Request semaphore */
 169                 iwl_set_bit(priv, CSR_HW_IF_CONFIG_REG,
 170                             CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM);
 171
 172                 /* See if we got it */
 173                 ret = iwl_poll_bit(priv, CSR_HW_IF_CONFIG_REG,
 174                                    CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM,
 175                                    CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM,
 176                                    EEPROM_SEM_TIMEOUT);
 177                 if (ret >= 0) {
 178                         IWL_DEBUG_IO("Acquired semaphore after %d tries.\n",
 179                                 count+1);
 180                         return ret;
 181                 }
 182         }
 183
 184         return ret;
 185 }
 186 EXPORT_SYMBOL(iwlcore_eeprom_acquire_semaphore);
 187
 188 void iwlcore_eeprom_release_semaphore(struct iwl_priv *priv)
 189 {
 190         iwl_clear_bit(priv, CSR_HW_IF_CONFIG_REG,
 191                 CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM);
 192
 193 }
 194 EXPORT_SYMBOL(iwlcore_eeprom_release_semaphore);
 195
 196
 197 /**
 198  * iwl_eeprom_init - read EEPROM contents
 199  *
 200  * Load the EEPROM contents from adapter into priv->eeprom
 201  *
 202  * NOTE:  This routine uses the non-debug IO access functions.
 203  */
 204 int iwl_eeprom_init(struct iwl_priv *priv)
 205 {
 206         u16 *e = (u16 *)&priv->eeprom;
 207         u32 gp = iwl_read32(priv, CSR_EEPROM_GP);
 208         u32 r;
 209         int sz = sizeof(priv->eeprom);
 210         int ret;
 211         int i;
 212         u16 addr;
 213
 214         /* The EEPROM structure has several padding buffers within it
 215          * and when adding new EEPROM maps is subject to programmer errors
 216          * which may be very difficult to identify without explicitly
 217          * checking the resulting size of the eeprom map. */
 218         BUILD_BUG_ON(sizeof(priv->eeprom) != IWL_EEPROM_IMAGE_SIZE);
 219
 220         if ((gp & CSR_EEPROM_GP_VALID_MSK) == CSR_EEPROM_GP_BAD_SIGNATURE) {
 221                 IWL_ERROR("EEPROM not found, EEPROM_GP=0x%08x", gp);
 222                 return -ENOENT;
 223         }
 224
 225         /* Make sure driver (instead of uCode) is allowed to read EEPROM */
 226         ret = priv->cfg->ops->lib->eeprom_ops.acquire_semaphore(priv);
 227         if (ret < 0) {
 228                 IWL_ERROR("Failed to acquire EEPROM semaphore.\n");
 229                 return -ENOENT;
 230         }
 231
 232         /* eeprom is an array of 16bit values */
 233         for (addr = 0; addr < sz; addr += sizeof(u16)) {
 234                 _iwl_write32(priv, CSR_EEPROM_REG, addr << 1);
 235                 _iwl_clear_bit(priv, CSR_EEPROM_REG, CSR_EEPROM_REG_BIT_CMD);
 236
 237                 for (i = 0; i < IWL_EEPROM_ACCESS_TIMEOUT;
 238                                         i += IWL_EEPROM_ACCESS_DELAY) {
 239                         r = _iwl_read_direct32(priv, CSR_EEPROM_REG);
 240                         if (r & CSR_EEPROM_REG_READ_VALID_MSK)
 241                                 break;
 242                         udelay(IWL_EEPROM_ACCESS_DELAY);
 243                 }
 244
 245                 if (!(r & CSR_EEPROM_REG_READ_VALID_MSK)) {
 246                         IWL_ERROR("Time out reading EEPROM[%d]", addr);
 247                         ret = -ETIMEDOUT;
 248                         goto done;
 249                 }
 250                 e[addr / 2] = le16_to_cpu((__force __le16)(r >> 16));
 251         }
 252         ret = 0;
 253
 254 done:
 255         priv->cfg->ops->lib->eeprom_ops.release_semaphore(priv);
 256         return ret;
 257 }
 258 EXPORT_SYMBOL(iwl_eeprom_init);
 259
 260
 261 void iwl_eeprom_get_mac(const struct iwl_priv *priv, u8 *mac)
 262 {
 263         memcpy(mac, priv->eeprom.mac_address, 6);
 264 }
 265 EXPORT_SYMBOL(iwl_eeprom_get_mac);
 266
 267 static void iwl_init_band_reference(const struct iwl_priv *priv,
 268                                     int band,
 269                                     int *eeprom_ch_count,
 270                                     const struct iwl4965_eeprom_channel
 271                                     **eeprom_ch_info,
 272                                     const u8 **eeprom_ch_index)
 273 {
 274         switch (band) {
 275         case 1:         /* 2.4GHz band */
 276                 *eeprom_ch_count = ARRAY_SIZE(iwl_eeprom_band_1);
 277                 *eeprom_ch_info = priv->eeprom.band_1_channels;
 278                 *eeprom_ch_index = iwl_eeprom_band_1;
 279                 break;
 280         case 2:         /* 4.9GHz band */
 281                 *eeprom_ch_count = ARRAY_SIZE(iwl_eeprom_band_2);
 282                 *eeprom_ch_info = priv->eeprom.band_2_channels;
 283                 *eeprom_ch_index = iwl_eeprom_band_2;
 284                 break;
 285         case 3:         /* 5.2GHz band */
 286                 *eeprom_ch_count = ARRAY_SIZE(iwl_eeprom_band_3);
 287                 *eeprom_ch_info = priv->eeprom.band_3_channels;
 288                 *eeprom_ch_index = iwl_eeprom_band_3;
 289                 break;
 290         case 4:         /* 5.5GHz band */
 291                 *eeprom_ch_count = ARRAY_SIZE(iwl_eeprom_band_4);
 292                 *eeprom_ch_info = priv->eeprom.band_4_channels;
 293                 *eeprom_ch_index = iwl_eeprom_band_4;
 294                 break;
 295         case 5:         /* 5.7GHz band */
 296                 *eeprom_ch_count = ARRAY_SIZE(iwl_eeprom_band_5);
 297                 *eeprom_ch_info = priv->eeprom.band_5_channels;
 298                 *eeprom_ch_index = iwl_eeprom_band_5;
 299                 break;
 300         case 6:         /* 2.4GHz FAT channels */
 301                 *eeprom_ch_count = ARRAY_SIZE(iwl_eeprom_band_6);
 302                 *eeprom_ch_info = priv->eeprom.band_24_channels;
 303                 *eeprom_ch_index = iwl_eeprom_band_6;
 304                 break;
 305         case 7:         /* 5 GHz FAT channels */
 306                 *eeprom_ch_count = ARRAY_SIZE(iwl_eeprom_band_7);
 307                 *eeprom_ch_info = priv->eeprom.band_52_channels;
 308                 *eeprom_ch_index = iwl_eeprom_band_7;
 309                 break;
 310         default:
 311                 BUG();
 312                 return;
 313         }
 314 }
 315
 316 #define CHECK_AND_PRINT(x) ((eeprom_ch->flags & EEPROM_CHANNEL_##x) \
 317                             ? # x " " : "")
 318
 319 /**
 320  * iwl4965_set_fat_chan_info - Copy fat channel info into driver's priv.
 321  *
 322  * Does not set up a command, or touch hardware.
 323  */
 324 static int iwl4965_set_fat_chan_info(struct iwl_priv *priv,
 325                               enum ieee80211_band band, u16 channel,
 326                               const struct iwl4965_eeprom_channel *eeprom_ch,
 327                               u8 fat_extension_channel)
 328 {
 329         struct iwl_channel_info *ch_info;
 330
 331         ch_info = (struct iwl_channel_info *)
 332                         iwl_get_channel_info(priv, band, channel);
 333
 334         if (!is_channel_valid(ch_info))
 335                 return -1;
 336
 337         IWL_DEBUG_INFO("FAT Ch. %d [%sGHz] %s%s%s%s%s%s(0x%02x"
 338                         " %ddBm): Ad-Hoc %ssupported\n",
 339                         ch_info->channel,
 340                         is_channel_a_band(ch_info) ?
 341                         "5.2" : "2.4",
 342                         CHECK_AND_PRINT(IBSS),
 343                         CHECK_AND_PRINT(ACTIVE),
 344                         CHECK_AND_PRINT(RADAR),
 345                         CHECK_AND_PRINT(WIDE),
 346                         CHECK_AND_PRINT(NARROW),
 347                         CHECK_AND_PRINT(DFS),
 348                         eeprom_ch->flags,
 349                         eeprom_ch->max_power_avg,
 350                         ((eeprom_ch->flags & EEPROM_CHANNEL_IBSS)
 351                          && !(eeprom_ch->flags & EEPROM_CHANNEL_RADAR)) ?
 352                         "" : "not ");
 353
 354         ch_info->fat_eeprom = *eeprom_ch;
 355         ch_info->fat_max_power_avg = eeprom_ch->max_power_avg;
 356         ch_info->fat_curr_txpow = eeprom_ch->max_power_avg;
 357         ch_info->fat_min_power = 0;
 358         ch_info->fat_scan_power = eeprom_ch->max_power_avg;
 359         ch_info->fat_flags = eeprom_ch->flags;
 360         ch_info->fat_extension_channel = fat_extension_channel;
 361
 362         return 0;
 363 }
 364
 365 #define CHECK_AND_PRINT_I(x) ((eeprom_ch_info[ch].flags & EEPROM_CHANNEL_##x) \
 366                             ? # x " " : "")
 367
 368 /**
 369  * iwl_init_channel_map - Set up driver's info for all possible channels
 370  */
 371 int iwl_init_channel_map(struct iwl_priv *priv)
 372 {
 373         int eeprom_ch_count = 0;
 374         const u8 *eeprom_ch_index = NULL;
 375         const struct iwl4965_eeprom_channel *eeprom_ch_info = NULL;
 376         int band, ch;
 377         struct iwl_channel_info *ch_info;
 378
 379         if (priv->channel_count) {
 380                 IWL_DEBUG_INFO("Channel map already initialized.\n");
 381                 return 0;
 382         }
 383
 384         if (priv->eeprom.version < 0x2f) {
 385                 IWL_WARNING("Unsupported EEPROM version: 0x%04X\n",
 386                             priv->eeprom.version);
 387                 return -EINVAL;
 388         }
 389
 390         IWL_DEBUG_INFO("Initializing regulatory info from EEPROM\n");
 391
 392         priv->channel_count =
 393             ARRAY_SIZE(iwl_eeprom_band_1) +
 394             ARRAY_SIZE(iwl_eeprom_band_2) +
 395             ARRAY_SIZE(iwl_eeprom_band_3) +
 396             ARRAY_SIZE(iwl_eeprom_band_4) +
 397             ARRAY_SIZE(iwl_eeprom_band_5);
 398
 399         IWL_DEBUG_INFO("Parsing data for %d channels.\n", priv->channel_count);
 400
 401         priv->channel_info = kzalloc(sizeof(struct iwl_channel_info) *
 402                                      priv->channel_count, GFP_KERNEL);
 403         if (!priv->channel_info) {
 404                 IWL_ERROR("Could not allocate channel_info\n");
 405                 priv->channel_count = 0;
 406                 return -ENOMEM;
 407         }
 408
 409         ch_info = priv->channel_info;
 410
 411         /* Loop through the 5 EEPROM bands adding them in order to the
 412          * channel map we maintain (that contains additional information than
 413          * what just in the EEPROM) */
 414         for (band = 1; band <= 5; band++) {
 415
 416                 iwl_init_band_reference(priv, band, &eeprom_ch_count,
 417                                         &eeprom_ch_info, &eeprom_ch_index);
 418
 419                 /* Loop through each band adding each of the channels */
 420                 for (ch = 0; ch < eeprom_ch_count; ch++) {
 421                         ch_info->channel = eeprom_ch_index[ch];
 422                         ch_info->band = (band == 1) ? IEEE80211_BAND_2GHZ :
 423                             IEEE80211_BAND_5GHZ;
 424
 425                         /* permanently store EEPROM's channel regulatory flags
 426                          *   and max power in channel info database. */
 427                         ch_info->eeprom = eeprom_ch_info[ch];
 428
 429                         /* Copy the run-time flags so they are there even on
 430                          * invalid channels */
 431                         ch_info->flags = eeprom_ch_info[ch].flags;
 432
 433                         if (!(is_channel_valid(ch_info))) {
 434                                 IWL_DEBUG_INFO("Ch. %d Flags %x [%sGHz] - "
 435                                                "No traffic\n",
 436                                                ch_info->channel,
 437                                                ch_info->flags,
 438                                                is_channel_a_band(ch_info) ?
 439                                                "5.2" : "2.4");
 440                                 ch_info++;
 441                                 continue;
 442                         }
 443
 444                         /* Initialize regulatory-based run-time data */
 445                         ch_info->max_power_avg = ch_info->curr_txpow =
 446                             eeprom_ch_info[ch].max_power_avg;
 447                         ch_info->scan_power = eeprom_ch_info[ch].max_power_avg;
 448                         ch_info->min_power = 0;
 449
 450                         IWL_DEBUG_INFO("Ch. %d [%sGHz] %s%s%s%s%s%s%s(0x%02x"
 451                                        " %ddBm): Ad-Hoc %ssupported\n",
 452                                        ch_info->channel,
 453                                        is_channel_a_band(ch_info) ?
 454                                        "5.2" : "2.4",
 455                                        CHECK_AND_PRINT_I(VALID),
 456                                        CHECK_AND_PRINT_I(IBSS),
 457                                        CHECK_AND_PRINT_I(ACTIVE),
 458                                        CHECK_AND_PRINT_I(RADAR),
 459                                        CHECK_AND_PRINT_I(WIDE),
 460                                        CHECK_AND_PRINT_I(NARROW),
 461                                        CHECK_AND_PRINT_I(DFS),
 462                                        eeprom_ch_info[ch].flags,
 463                                        eeprom_ch_info[ch].max_power_avg,
 464                                        ((eeprom_ch_info[ch].
 465                                          flags & EEPROM_CHANNEL_IBSS)
 466                                         && !(eeprom_ch_info[ch].
 467                                              flags & EEPROM_CHANNEL_RADAR))
 468                                        ? "" : "not ");
 469
 470                         /* Set the user_txpower_limit to the highest power
 471                          * supported by any channel */
 472                         if (eeprom_ch_info[ch].max_power_avg >
 473                             priv->user_txpower_limit)
 474                                 priv->user_txpower_limit =
 475                                     eeprom_ch_info[ch].max_power_avg;
 476
 477                         ch_info++;
 478                 }
 479         }
 480
 481         /* Two additional EEPROM bands for 2.4 and 5 GHz FAT channels */
 482         for (band = 6; band <= 7; band++) {
 483                 enum ieee80211_band ieeeband;
 484                 u8 fat_extension_chan;
 485
 486                 iwl_init_band_reference(priv, band, &eeprom_ch_count,
 487                                         &eeprom_ch_info, &eeprom_ch_index);
 488
 489                 /* EEPROM band 6 is 2.4, band 7 is 5 GHz */
 490                 ieeeband =
 491                         (band == 6) ? IEEE80211_BAND_2GHZ : IEEE80211_BAND_5GHZ;
 492
 493                 /* Loop through each band adding each of the channels */
 494                 for (ch = 0; ch < eeprom_ch_count; ch++) {
 495
 496                         if ((band == 6) &&
 497                             ((eeprom_ch_index[ch] == 5) ||
 498                             (eeprom_ch_index[ch] == 6) ||
 499                             (eeprom_ch_index[ch] == 7)))
 500                                fat_extension_chan = HT_IE_EXT_CHANNEL_MAX;
 501                         else
 502                                 fat_extension_chan = HT_IE_EXT_CHANNEL_ABOVE;
 503
 504                         /* Set up driver's info for lower half */
 505                         iwl4965_set_fat_chan_info(priv, ieeeband,
 506                                                   eeprom_ch_index[ch],
 507                                                   &(eeprom_ch_info[ch]),
 508                                                   fat_extension_chan);
 509
 510                         /* Set up driver's info for upper half */
 511                         iwl4965_set_fat_chan_info(priv, ieeeband,
 512                                                   (eeprom_ch_index[ch] + 4),
 513                                                   &(eeprom_ch_info[ch]),
 514                                                   HT_IE_EXT_CHANNEL_BELOW);
 515                 }
 516         }
 517
 518         return 0;
 519 }
 520 EXPORT_SYMBOL(iwl_init_channel_map);
 521
 522 /*
 523  * iwl_free_channel_map - undo allocations in iwl4965_init_channel_map
 524  */
 525 void iwl_free_channel_map(struct iwl_priv *priv)
 526 {
 527         kfree(priv->channel_info);
 528         priv->channel_count = 0;
 529 }
 530 EXPORT_SYMBOL(iwl_free_channel_map);
 531
 532 /**
 533  * iwl_get_channel_info - Find driver's private channel info
 534  *
 535  * Based on band and channel number.
 536  */
 537 const struct iwl_channel_info *iwl_get_channel_info(
 538                 const struct iwl_priv *priv,
 539                 enum ieee80211_band band, u16 channel)
 540 {
 541         int i;
 542
 543         switch (band) {
 544         case IEEE80211_BAND_5GHZ:
 545                 for (i = 14; i < priv->channel_count; i++) {
 546                         if (priv->channel_info[i].channel == channel)
 547                                 return &priv->channel_info[i];
 548                 }
 549                 break;
 550         case IEEE80211_BAND_2GHZ:
 551                 if (channel >= 1 && channel <= 14)
 552                         return &priv->channel_info[channel - 1];
 553                 break;
 554         default:
 555                 BUG();
 556         }
 557
 558         return NULL;
 559 }
 560 EXPORT_SYMBOL(iwl_get_channel_info);
 561