LXR linux/net/mac80211/regdomain.c

   1/*
   2 * Copyright 2002-2005, Instant802 Networks, Inc.
   3 * Copyright 2005-2006, Devicescape Software, Inc.
   4 *
   5 * This program is free software; you can redistribute it and/or modify
   6 * it under the terms of the GNU General Public License version 2 as
   7 * published by the Free Software Foundation.
   8 */
   9
  10/*
  11 * This regulatory domain control implementation is known to be incomplete
  12 * and confusing. mac80211 regulatory domain control will be significantly
  13 * reworked in the not-too-distant future.
  14 *
  15 * For now, drivers wishing to control which channels are and aren't available
  16 * are advised as follows:
  17 *  - set the IEEE80211_HW_DEFAULT_REG_DOMAIN_CONFIGURED flag
  18 *  - continue to include *ALL* possible channels in the modes registered
  19 *    through ieee80211_register_hwmode()
  20 *  - for each allowable ieee80211_channel structure registered in the above
  21 *    call, set the flag member to some meaningful value such as
  22 *    IEEE80211_CHAN_W_SCAN | IEEE80211_CHAN_W_ACTIVE_SCAN |
  23 *    IEEE80211_CHAN_W_IBSS.
  24 *  - leave flag as 0 for non-allowable channels
  25 *
  26 * The usual implementation is for a driver to read a device EEPROM to
  27 * determine which regulatory domain it should be operating under, then
  28 * looking up the allowable channels in a driver-local table, then performing
  29 * the above.
  30 */
  31
  32#include <linux/module.h>
  33#include <linux/netdevice.h>
  34#include <net/mac80211.h>
  35#include "ieee80211_i.h"
  36
  37static int ieee80211_regdom = 0x10; /* FCC */
  38module_param(ieee80211_regdom, int, 0444);
  39MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain; 64=MKK");
  40
  41/*
  42 * If firmware is upgraded by the vendor, additional channels can be used based
  43 * on the new Japanese regulatory rules. This is indicated by setting
  44 * ieee80211_japan_5ghz module parameter to one when loading the 80211 kernel
  45 * module.
  46 */
  47static int ieee80211_japan_5ghz /* = 0 */;
  48module_param(ieee80211_japan_5ghz, int, 0444);
  49MODULE_PARM_DESC(ieee80211_japan_5ghz, "Vendor-updated firmware for 5 GHz");
  50
  51
  52struct ieee80211_channel_range {
  53        short start_freq;
  54        short end_freq;
  55        unsigned char power_level;
  56        unsigned char antenna_max;
  57};
  58
  59static const struct ieee80211_channel_range ieee80211_fcc_channels[] = {
  60        { 2412, 2462, 27, 6 } /* IEEE 802.11b/g, channels 1..11 */,
  61        { 5180, 5240, 17, 6 } /* IEEE 802.11a, channels 36..48 */,
  62        { 5260, 5320, 23, 6 } /* IEEE 802.11a, channels 52..64 */,
  63        { 5745, 5825, 30, 6 } /* IEEE 802.11a, channels 149..165, outdoor */,
  64        { 0 }
  65};
  66
  67static const struct ieee80211_channel_range ieee80211_mkk_channels[] = {
  68        { 2412, 2472, 20, 6 } /* IEEE 802.11b/g, channels 1..13 */,
  69        { 5170, 5240, 20, 6 } /* IEEE 802.11a, channels 34..48 */,
  70        { 5260, 5320, 20, 6 } /* IEEE 802.11a, channels 52..64 */,
  71        { 0 }
  72};
  73
  74
  75static const struct ieee80211_channel_range *channel_range =
  76        ieee80211_fcc_channels;
  77
  78
  79static void ieee80211_unmask_channel(int mode, struct ieee80211_channel *chan)
  80{
  81        int i;
  82
  83        chan->flag = 0;
  84
  85        for (i = 0; channel_range[i].start_freq; i++) {
  86                const struct ieee80211_channel_range *r = &channel_range[i];
  87                if (r->start_freq <= chan->freq && r->end_freq >= chan->freq) {
  88                        if (ieee80211_regdom == 64 && !ieee80211_japan_5ghz &&
  89                            chan->freq >= 5260 && chan->freq <= 5320) {
  90                                /*
  91                                 * Skip new channels in Japan since the
  92                                 * firmware was not marked having been upgraded
  93                                 * by the vendor.
  94                                 */
  95                                continue;
  96                        }
  97
  98                        if (ieee80211_regdom == 0x10 &&
  99                            (chan->freq == 5190 || chan->freq == 5210 ||
 100                             chan->freq == 5230)) {
 101                                    /* Skip MKK channels when in FCC domain. */
 102                                    continue;
 103                        }
 104
 105                        chan->flag |= IEEE80211_CHAN_W_SCAN |
 106                                IEEE80211_CHAN_W_ACTIVE_SCAN |
 107                                IEEE80211_CHAN_W_IBSS;
 108                        chan->power_level = r->power_level;
 109                        chan->antenna_max = r->antenna_max;
 110
 111                        if (ieee80211_regdom == 64 &&
 112                            (chan->freq == 5170 || chan->freq == 5190 ||
 113                             chan->freq == 5210 || chan->freq == 5230)) {
 114                                /*
 115                                 * New regulatory rules in Japan have backwards
 116                                 * compatibility with old channels in 5.15-5.25
 117                                 * GHz band, but the station is not allowed to
 118                                 * use active scan on these old channels.
 119                                 */
 120                                chan->flag &= ~IEEE80211_CHAN_W_ACTIVE_SCAN;
 121                        }
 122
 123                        if (ieee80211_regdom == 64 &&
 124                            (chan->freq == 5260 || chan->freq == 5280 ||
 125                             chan->freq == 5300 || chan->freq == 5320)) {
 126                                /*
 127                                 * IBSS is not allowed on 5.25-5.35 GHz band
 128                                 * due to radar detection requirements.
 129                                 */
 130                                chan->flag &= ~IEEE80211_CHAN_W_IBSS;
 131                        }
 132
 133                        break;
 134                }
 135        }
 136}
 137
 138
 139void ieee80211_set_default_regdomain(struct ieee80211_hw_mode *mode)
 140{
 141        int c;
 142        for (c = 0; c < mode->num_channels; c++)
 143                ieee80211_unmask_channel(mode->mode, &mode->channels[c]);
 144}
 145
 146
 147void ieee80211_regdomain_init(void)
 148{
 149        if (ieee80211_regdom == 0x40)
 150                channel_range = ieee80211_mkk_channels;
 151}
 152
 153