Johannes Berg | 8318d78 | 2008-01-24 19:38:38 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2002-2005, Instant802 Networks, Inc. |
| 3 | * Copyright 2005-2006, Devicescape Software, Inc. |
| 4 | * Copyright 2007 Johannes Berg <johannes@sipsolutions.net> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | */ |
| 10 | |
| 11 | /* |
| 12 | * This regulatory domain control implementation is highly incomplete, it |
| 13 | * only exists for the purpose of not regressing mac80211. |
| 14 | * |
| 15 | * For now, drivers can restrict the set of allowed channels by either |
| 16 | * not registering those channels or setting the IEEE80211_CHAN_DISABLED |
| 17 | * flag; that flag will only be *set* by this code, never *cleared. |
| 18 | * |
| 19 | * The usual implementation is for a driver to read a device EEPROM to |
| 20 | * determine which regulatory domain it should be operating under, then |
| 21 | * looking up the allowable channels in a driver-local table and finally |
| 22 | * registering those channels in the wiphy structure. |
| 23 | * |
| 24 | * Alternatively, drivers that trust the regulatory domain control here |
| 25 | * will register a complete set of capabilities and the control code |
| 26 | * will restrict the set by setting the IEEE80211_CHAN_* flags. |
| 27 | */ |
| 28 | #include <linux/kernel.h> |
| 29 | #include <net/wireless.h> |
| 30 | #include "core.h" |
| 31 | |
| 32 | static char *ieee80211_regdom = "US"; |
| 33 | module_param(ieee80211_regdom, charp, 0444); |
| 34 | MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code"); |
| 35 | |
| 36 | struct ieee80211_channel_range { |
| 37 | short start_freq; |
| 38 | short end_freq; |
| 39 | int max_power; |
| 40 | int max_antenna_gain; |
| 41 | u32 flags; |
| 42 | }; |
| 43 | |
| 44 | struct ieee80211_regdomain { |
| 45 | const char *code; |
| 46 | const struct ieee80211_channel_range *ranges; |
| 47 | int n_ranges; |
| 48 | }; |
| 49 | |
| 50 | #define RANGE_PWR(_start, _end, _pwr, _ag, _flags) \ |
| 51 | { _start, _end, _pwr, _ag, _flags } |
| 52 | |
| 53 | |
| 54 | /* |
| 55 | * Ideally, in the future, these definitions will be loaded from a |
| 56 | * userspace table via some daemon. |
| 57 | */ |
| 58 | static const struct ieee80211_channel_range ieee80211_US_channels[] = { |
| 59 | /* IEEE 802.11b/g, channels 1..11 */ |
| 60 | RANGE_PWR(2412, 2462, 27, 6, 0), |
Tomas Winkler | b46b4ee | 2008-02-13 20:58:34 +0200 | [diff] [blame] | 61 | /* IEEE 802.11a, channel 36*/ |
| 62 | RANGE_PWR(5180, 5180, 23, 6, 0), |
| 63 | /* IEEE 802.11a, channel 40*/ |
| 64 | RANGE_PWR(5200, 5200, 23, 6, 0), |
| 65 | /* IEEE 802.11a, channel 44*/ |
| 66 | RANGE_PWR(5220, 5220, 23, 6, 0), |
| 67 | /* IEEE 802.11a, channels 48..64 */ |
| 68 | RANGE_PWR(5240, 5320, 23, 6, 0), |
Johannes Berg | 8318d78 | 2008-01-24 19:38:38 +0100 | [diff] [blame] | 69 | /* IEEE 802.11a, channels 149..165, outdoor */ |
| 70 | RANGE_PWR(5745, 5825, 30, 6, 0), |
| 71 | }; |
| 72 | |
| 73 | static const struct ieee80211_channel_range ieee80211_JP_channels[] = { |
| 74 | /* IEEE 802.11b/g, channels 1..14 */ |
| 75 | RANGE_PWR(2412, 2484, 20, 6, 0), |
| 76 | /* IEEE 802.11a, channels 34..48 */ |
| 77 | RANGE_PWR(5170, 5240, 20, 6, IEEE80211_CHAN_PASSIVE_SCAN), |
| 78 | /* IEEE 802.11a, channels 52..64 */ |
| 79 | RANGE_PWR(5260, 5320, 20, 6, IEEE80211_CHAN_NO_IBSS | |
| 80 | IEEE80211_CHAN_RADAR), |
| 81 | }; |
| 82 | |
| 83 | #define REGDOM(_code) \ |
| 84 | { \ |
| 85 | .code = __stringify(_code), \ |
| 86 | .ranges = ieee80211_ ##_code## _channels, \ |
| 87 | .n_ranges = ARRAY_SIZE(ieee80211_ ##_code## _channels), \ |
| 88 | } |
| 89 | |
| 90 | static const struct ieee80211_regdomain ieee80211_regdoms[] = { |
| 91 | REGDOM(US), |
| 92 | REGDOM(JP), |
| 93 | }; |
| 94 | |
| 95 | |
| 96 | static const struct ieee80211_regdomain *get_regdom(void) |
| 97 | { |
| 98 | static const struct ieee80211_channel_range |
| 99 | ieee80211_world_channels[] = { |
| 100 | /* IEEE 802.11b/g, channels 1..11 */ |
| 101 | RANGE_PWR(2412, 2462, 27, 6, 0), |
| 102 | }; |
| 103 | static const struct ieee80211_regdomain regdom_world = REGDOM(world); |
| 104 | int i; |
| 105 | |
| 106 | for (i = 0; i < ARRAY_SIZE(ieee80211_regdoms); i++) |
| 107 | if (strcmp(ieee80211_regdom, ieee80211_regdoms[i].code) == 0) |
| 108 | return &ieee80211_regdoms[i]; |
| 109 | |
| 110 | return ®dom_world; |
| 111 | } |
| 112 | |
| 113 | |
| 114 | static void handle_channel(struct ieee80211_channel *chan, |
| 115 | const struct ieee80211_regdomain *rd) |
| 116 | { |
| 117 | int i; |
| 118 | u32 flags = chan->orig_flags; |
| 119 | const struct ieee80211_channel_range *rg = NULL; |
| 120 | |
| 121 | for (i = 0; i < rd->n_ranges; i++) { |
| 122 | if (rd->ranges[i].start_freq <= chan->center_freq && |
| 123 | chan->center_freq <= rd->ranges[i].end_freq) { |
| 124 | rg = &rd->ranges[i]; |
| 125 | break; |
| 126 | } |
| 127 | } |
| 128 | |
| 129 | if (!rg) { |
| 130 | /* not found */ |
| 131 | flags |= IEEE80211_CHAN_DISABLED; |
| 132 | chan->flags = flags; |
| 133 | return; |
| 134 | } |
| 135 | |
| 136 | chan->flags = flags; |
| 137 | chan->max_antenna_gain = min(chan->orig_mag, |
| 138 | rg->max_antenna_gain); |
John W. Linville | 253898c | 2008-04-03 15:32:54 -0400 | [diff] [blame] | 139 | if (chan->orig_mpwr) |
| 140 | chan->max_power = min(chan->orig_mpwr, rg->max_power); |
| 141 | else |
| 142 | chan->max_power = rg->max_power; |
Johannes Berg | 8318d78 | 2008-01-24 19:38:38 +0100 | [diff] [blame] | 143 | } |
| 144 | |
| 145 | static void handle_band(struct ieee80211_supported_band *sband, |
| 146 | const struct ieee80211_regdomain *rd) |
| 147 | { |
| 148 | int i; |
| 149 | |
| 150 | for (i = 0; i < sband->n_channels; i++) |
| 151 | handle_channel(&sband->channels[i], rd); |
| 152 | } |
| 153 | |
| 154 | void wiphy_update_regulatory(struct wiphy *wiphy) |
| 155 | { |
| 156 | enum ieee80211_band band; |
| 157 | const struct ieee80211_regdomain *rd = get_regdom(); |
| 158 | |
| 159 | for (band = 0; band < IEEE80211_NUM_BANDS; band++) |
| 160 | if (wiphy->bands[band]) |
| 161 | handle_band(wiphy->bands[band], rd); |
| 162 | } |