linux/net/mac80211/vht.c
Johannes Berg 8921d04e8d mac80211: track number of spatial streams
With VHT, a station can change the number of spatial
streams it can receive on the fly, not unlike spatial
multiplexing in HT. Prepare for that by tracking the
maximum number of spatial streams it can receive when
the connection is established.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-02-15 09:41:31 +01:00

118 lines
3.0 KiB
C

/*
* VHT handling
*
* 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.
*/
#include <linux/ieee80211.h>
#include <linux/export.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
void ieee80211_vht_cap_ie_to_sta_vht_cap(struct ieee80211_sub_if_data *sdata,
struct ieee80211_supported_band *sband,
struct ieee80211_vht_cap *vht_cap_ie,
struct sta_info *sta)
{
struct ieee80211_sta_vht_cap *vht_cap = &sta->sta.vht_cap;
memset(vht_cap, 0, sizeof(*vht_cap));
if (!sta->sta.ht_cap.ht_supported)
return;
if (!vht_cap_ie || !sband->vht_cap.vht_supported)
return;
/* A VHT STA must support 40 MHz */
if (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
return;
vht_cap->vht_supported = true;
vht_cap->cap = le32_to_cpu(vht_cap_ie->vht_cap_info);
/* Copy peer MCS info, the driver might need them. */
memcpy(&vht_cap->vht_mcs, &vht_cap_ie->supp_mcs,
sizeof(struct ieee80211_vht_mcs_info));
sta->sta.bandwidth = ieee80211_sta_cur_vht_bw(sta);
}
enum ieee80211_sta_rx_bandwidth ieee80211_sta_cur_vht_bw(struct sta_info *sta)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
u32 cap = sta->sta.vht_cap.cap;
if (!sta->sta.vht_cap.vht_supported)
return sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
/* TODO: handle VHT opmode notification data */
switch (sdata->vif.bss_conf.chandef.width) {
default:
WARN_ON_ONCE(1);
/* fall through */
case NL80211_CHAN_WIDTH_20_NOHT:
case NL80211_CHAN_WIDTH_20:
case NL80211_CHAN_WIDTH_40:
return sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
case NL80211_CHAN_WIDTH_160:
if (cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ)
return IEEE80211_STA_RX_BW_160;
/* fall through */
case NL80211_CHAN_WIDTH_80P80:
if (cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
return IEEE80211_STA_RX_BW_160;
/* fall through */
case NL80211_CHAN_WIDTH_80:
return IEEE80211_STA_RX_BW_80;
}
}
void ieee80211_sta_set_rx_nss(struct sta_info *sta)
{
u8 ht_rx_nss = 0, vht_rx_nss = 0;
/* if we received a notification already don't overwrite it */
if (sta->sta.rx_nss)
return;
if (sta->sta.ht_cap.ht_supported) {
if (sta->sta.ht_cap.mcs.rx_mask[0])
ht_rx_nss++;
if (sta->sta.ht_cap.mcs.rx_mask[1])
ht_rx_nss++;
if (sta->sta.ht_cap.mcs.rx_mask[2])
ht_rx_nss++;
if (sta->sta.ht_cap.mcs.rx_mask[3])
ht_rx_nss++;
/* FIXME: consider rx_highest? */
}
if (sta->sta.vht_cap.vht_supported) {
int i;
u16 rx_mcs_map;
rx_mcs_map = le16_to_cpu(sta->sta.vht_cap.vht_mcs.rx_mcs_map);
for (i = 7; i >= 0; i--) {
u8 mcs = (rx_mcs_map >> (2 * i)) & 3;
if (mcs != IEEE80211_VHT_MCS_NOT_SUPPORTED) {
vht_rx_nss = i + 1;
break;
}
}
/* FIXME: consider rx_highest? */
}
ht_rx_nss = max(ht_rx_nss, vht_rx_nss);
sta->sta.rx_nss = max_t(u8, 1, ht_rx_nss);
}