/*
* 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),
/* 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),
/* 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),
};
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),
};
#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),
REGDOM(EU),
};
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 ®dom_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);
if (chan->orig_mpwr)
chan->max_power = min(chan->orig_mpwr, rg->max_power);
else
chan->max_power = rg->max_power;
}
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);
}
