mac80211: allow disabling 40MHz on 2.4GHz

In some situations it is required that a system be
configured with no support for 40 MHz channels in
the 2.4 GHz band. Rather than imposing any such
restrictions on everybody, allow configuration a
system like that with a module parameter. It is
writable at runtime but only takes effect at the
time of the next association.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Johannes Berg 2009-12-01 18:29:42 +01:00 committed by John W. Linville
parent 8b73d13a21
commit f38fd12fa7
4 changed files with 25 additions and 3 deletions

View File

@ -881,6 +881,8 @@ void ieee80211_bss_info_change_notify(struct ieee80211_sub_if_data *sdata,
void ieee80211_configure_filter(struct ieee80211_local *local);
u32 ieee80211_reset_erp_info(struct ieee80211_sub_if_data *sdata);
extern bool ieee80211_disable_40mhz_24ghz;
/* STA code */
void ieee80211_sta_setup_sdata(struct ieee80211_sub_if_data *sdata);
int ieee80211_mgd_auth(struct ieee80211_sub_if_data *sdata,

View File

@ -33,6 +33,12 @@
#include "cfg.h"
#include "debugfs.h"
bool ieee80211_disable_40mhz_24ghz;
module_param(ieee80211_disable_40mhz_24ghz, bool, 0644);
MODULE_PARM_DESC(ieee80211_disable_40mhz_24ghz,
"Disable 40MHz support in the 2.4GHz band");
void ieee80211_configure_filter(struct ieee80211_local *local)
{
u64 mc;

View File

@ -400,6 +400,12 @@ static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata,
/* determine capability flags */
if (ieee80211_disable_40mhz_24ghz &&
sband->band == IEEE80211_BAND_2GHZ) {
cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
cap &= ~IEEE80211_HT_CAP_SGI_40;
}
switch (ht_info->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
if (flags & IEEE80211_CHAN_NO_HT40PLUS) {

View File

@ -908,16 +908,24 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
}
if (sband->ht_cap.ht_supported) {
__le16 tmp = cpu_to_le16(sband->ht_cap.cap);
u16 cap = sband->ht_cap.cap;
__le16 tmp;
if (ieee80211_disable_40mhz_24ghz &&
sband->band == IEEE80211_BAND_2GHZ) {
cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
cap &= ~IEEE80211_HT_CAP_SGI_40;
}
*pos++ = WLAN_EID_HT_CAPABILITY;
*pos++ = sizeof(struct ieee80211_ht_cap);
memset(pos, 0, sizeof(struct ieee80211_ht_cap));
tmp = cpu_to_le16(cap);
memcpy(pos, &tmp, sizeof(u16));
pos += sizeof(u16);
/* TODO: needs a define here for << 2 */
*pos++ = sband->ht_cap.ampdu_factor |
(sband->ht_cap.ampdu_density << 2);
(sband->ht_cap.ampdu_density <<
IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT);
memcpy(pos, &sband->ht_cap.mcs, sizeof(sband->ht_cap.mcs));
pos += sizeof(sband->ht_cap.mcs);
pos += 2 + 4 + 1; /* ext info, BF cap, antsel */