2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2005-2006, Devicescape Software, Inc.
4 * Copyright 2007 Johannes Berg <johannes@sipsolutions.net>
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.
12 * This regulatory domain control implementation is highly incomplete, it
13 * only exists for the purpose of not regressing mac80211.
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.
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.
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.
28 #include <linux/kernel.h>
29 #include <net/wireless.h>
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");
36 struct ieee80211_channel_range {
44 struct ieee80211_regdomain {
46 const struct ieee80211_channel_range *ranges;
50 #define RANGE_PWR(_start, _end, _pwr, _ag, _flags) \
51 { _start, _end, _pwr, _ag, _flags }
55 * Ideally, in the future, these definitions will be loaded from a
56 * userspace table via some daemon.
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),
61 /* IEEE 802.11a, channels 52..64 */
62 RANGE_PWR(5260, 5320, 23, 6, 0),
63 /* IEEE 802.11a, channels 149..165, outdoor */
64 RANGE_PWR(5745, 5825, 30, 6, 0),
67 static const struct ieee80211_channel_range ieee80211_JP_channels[] = {
68 /* IEEE 802.11b/g, channels 1..14 */
69 RANGE_PWR(2412, 2484, 20, 6, 0),
70 /* IEEE 802.11a, channels 34..48 */
71 RANGE_PWR(5170, 5240, 20, 6, IEEE80211_CHAN_PASSIVE_SCAN),
72 /* IEEE 802.11a, channels 52..64 */
73 RANGE_PWR(5260, 5320, 20, 6, IEEE80211_CHAN_NO_IBSS |
74 IEEE80211_CHAN_RADAR),
77 #define REGDOM(_code) \
79 .code = __stringify(_code), \
80 .ranges = ieee80211_ ##_code## _channels, \
81 .n_ranges = ARRAY_SIZE(ieee80211_ ##_code## _channels), \
84 static const struct ieee80211_regdomain ieee80211_regdoms[] = {
90 static const struct ieee80211_regdomain *get_regdom(void)
92 static const struct ieee80211_channel_range
93 ieee80211_world_channels[] = {
94 /* IEEE 802.11b/g, channels 1..11 */
95 RANGE_PWR(2412, 2462, 27, 6, 0),
97 static const struct ieee80211_regdomain regdom_world = REGDOM(world);
100 for (i = 0; i < ARRAY_SIZE(ieee80211_regdoms); i++)
101 if (strcmp(ieee80211_regdom, ieee80211_regdoms[i].code) == 0)
102 return &ieee80211_regdoms[i];
104 return ®dom_world;
108 static void handle_channel(struct ieee80211_channel *chan,
109 const struct ieee80211_regdomain *rd)
112 u32 flags = chan->orig_flags;
113 const struct ieee80211_channel_range *rg = NULL;
115 for (i = 0; i < rd->n_ranges; i++) {
116 if (rd->ranges[i].start_freq <= chan->center_freq &&
117 chan->center_freq <= rd->ranges[i].end_freq) {
125 flags |= IEEE80211_CHAN_DISABLED;
131 chan->max_antenna_gain = min(chan->orig_mag,
132 rg->max_antenna_gain);
133 chan->max_power = min(chan->orig_mpwr, rg->max_power);
136 static void handle_band(struct ieee80211_supported_band *sband,
137 const struct ieee80211_regdomain *rd)
141 for (i = 0; i < sband->n_channels; i++)
142 handle_channel(&sband->channels[i], rd);
145 void wiphy_update_regulatory(struct wiphy *wiphy)
147 enum ieee80211_band band;
148 const struct ieee80211_regdomain *rd = get_regdom();
150 for (band = 0; band < IEEE80211_NUM_BANDS; band++)
151 if (wiphy->bands[band])
152 handle_band(wiphy->bands[band], rd);