reg.c 5.2 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
/*
 * Copyright 2002-2005, Instant802 Networks, Inc.
 * Copyright 2005-2006, Devicescape Software, Inc.
 * Copyright 2007	Johannes Berg <johannes@sipsolutions.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

/*
 * This regulatory domain control implementation is highly incomplete, it
 * only exists for the purpose of not regressing mac80211.
 *
 * For now, drivers can restrict the set of allowed channels by either
 * not registering those channels or setting the IEEE80211_CHAN_DISABLED
 * flag; that flag will only be *set* by this code, never *cleared.
 *
 * The usual implementation is for a driver to read a device EEPROM to
 * determine which regulatory domain it should be operating under, then
 * looking up the allowable channels in a driver-local table and finally
 * registering those channels in the wiphy structure.
 *
 * Alternatively, drivers that trust the regulatory domain control here
 * will register a complete set of capabilities and the control code
 * will restrict the set by setting the IEEE80211_CHAN_* flags.
 */
#include <linux/kernel.h>
#include <net/wireless.h>
#include "core.h"

static char *ieee80211_regdom = "US";
module_param(ieee80211_regdom, charp, 0444);
MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");

struct ieee80211_channel_range {
	short start_freq;
	short end_freq;
	int max_power;
	int max_antenna_gain;
	u32 flags;
};

struct ieee80211_regdomain {
	const char *code;
	const struct ieee80211_channel_range *ranges;
	int n_ranges;
};

#define RANGE_PWR(_start, _end, _pwr, _ag, _flags)	\
	{ _start, _end, _pwr, _ag, _flags }


/*
 * Ideally, in the future, these definitions will be loaded from a
 * userspace table via some daemon.
 */
static const struct ieee80211_channel_range ieee80211_US_channels[] = {
	/* IEEE 802.11b/g, channels 1..11 */
	RANGE_PWR(2412, 2462, 27, 6, 0),
61 62 63 64 65 66 67 68
	/* IEEE 802.11a, channel 36*/
	RANGE_PWR(5180, 5180, 23, 6, 0),
	/* IEEE 802.11a, channel 40*/
	RANGE_PWR(5200, 5200, 23, 6, 0),
	/* IEEE 802.11a, channel 44*/
	RANGE_PWR(5220, 5220, 23, 6, 0),
	/* IEEE 802.11a, channels 48..64 */
	RANGE_PWR(5240, 5320, 23, 6, 0),
69 70 71 72 73 74 75 76 77 78 79 80 81 82
	/* IEEE 802.11a, channels 149..165, outdoor */
	RANGE_PWR(5745, 5825, 30, 6, 0),
};

static const struct ieee80211_channel_range ieee80211_JP_channels[] = {
	/* IEEE 802.11b/g, channels 1..14 */
	RANGE_PWR(2412, 2484, 20, 6, 0),
	/* IEEE 802.11a, channels 34..48 */
	RANGE_PWR(5170, 5240, 20, 6, IEEE80211_CHAN_PASSIVE_SCAN),
	/* IEEE 802.11a, channels 52..64 */
	RANGE_PWR(5260, 5320, 20, 6, IEEE80211_CHAN_NO_IBSS |
				     IEEE80211_CHAN_RADAR),
};

83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99
static const struct ieee80211_channel_range ieee80211_EU_channels[] = {
	/* IEEE 802.11b/g, channels 1..13 */
	RANGE_PWR(2412, 2472, 20, 6, 0),
	/* IEEE 802.11a, channel 36*/
	RANGE_PWR(5180, 5180, 23, 6, IEEE80211_CHAN_PASSIVE_SCAN),
	/* IEEE 802.11a, channel 40*/
	RANGE_PWR(5200, 5200, 23, 6, IEEE80211_CHAN_PASSIVE_SCAN),
	/* IEEE 802.11a, channel 44*/
	RANGE_PWR(5220, 5220, 23, 6, IEEE80211_CHAN_PASSIVE_SCAN),
	/* IEEE 802.11a, channels 48..64 */
	RANGE_PWR(5240, 5320, 23, 6, IEEE80211_CHAN_NO_IBSS |
				     IEEE80211_CHAN_RADAR),
	/* IEEE 802.11a, channels 100..140 */
	RANGE_PWR(5500, 5700, 30, 6, IEEE80211_CHAN_NO_IBSS |
				     IEEE80211_CHAN_RADAR),
};

100 101 102 103 104 105 106 107 108 109
#define REGDOM(_code)							\
	{								\
		.code = __stringify(_code),				\
		.ranges = ieee80211_ ##_code## _channels,		\
		.n_ranges = ARRAY_SIZE(ieee80211_ ##_code## _channels),	\
	}

static const struct ieee80211_regdomain ieee80211_regdoms[] = {
	REGDOM(US),
	REGDOM(JP),
110
	REGDOM(EU),
111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156
};


static const struct ieee80211_regdomain *get_regdom(void)
{
	static const struct ieee80211_channel_range
	ieee80211_world_channels[] = {
		/* IEEE 802.11b/g, channels 1..11 */
		RANGE_PWR(2412, 2462, 27, 6, 0),
	};
	static const struct ieee80211_regdomain regdom_world = REGDOM(world);
	int i;

	for (i = 0; i < ARRAY_SIZE(ieee80211_regdoms); i++)
		if (strcmp(ieee80211_regdom, ieee80211_regdoms[i].code) == 0)
			return &ieee80211_regdoms[i];

	return &regdom_world;
}


static void handle_channel(struct ieee80211_channel *chan,
			   const struct ieee80211_regdomain *rd)
{
	int i;
	u32 flags = chan->orig_flags;
	const struct ieee80211_channel_range *rg = NULL;

	for (i = 0; i < rd->n_ranges; i++) {
		if (rd->ranges[i].start_freq <= chan->center_freq &&
		    chan->center_freq <= rd->ranges[i].end_freq) {
			rg = &rd->ranges[i];
			break;
		}
	}

	if (!rg) {
		/* not found */
		flags |= IEEE80211_CHAN_DISABLED;
		chan->flags = flags;
		return;
	}

	chan->flags = flags;
	chan->max_antenna_gain = min(chan->orig_mag,
					 rg->max_antenna_gain);
157 158 159 160
	if (chan->orig_mpwr)
		chan->max_power = min(chan->orig_mpwr, rg->max_power);
	else
		chan->max_power = rg->max_power;
161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180
}

static void handle_band(struct ieee80211_supported_band *sband,
			const struct ieee80211_regdomain *rd)
{
	int i;

	for (i = 0; i < sband->n_channels; i++)
		handle_channel(&sband->channels[i], rd);
}

void wiphy_update_regulatory(struct wiphy *wiphy)
{
	enum ieee80211_band band;
	const struct ieee80211_regdomain *rd = get_regdom();

	for (band = 0; band < IEEE80211_NUM_BANDS; band++)
		if (wiphy->bands[band])
			handle_band(wiphy->bands[band], rd);
}
新手
引导
客服 返回
顶部