leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

mac80211: support VHT association

Browse Source 
Determine the VHT channel from the AP's VHT operation IE
(if present) and configure the hardware to that channel
if it is supported. If channel contexts cause a channel
to not be usable, try a smaller bandwidth.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Johannes Berg 2012-11-22 14:11:39 +01:00
parent 9f5e8f6efc
commit f2d9d270c1
3 changed files with 313 additions and 72 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
include/linux/ieee80211.h
View File

@ -1212,6 +1212,21 @@ struct ieee80211_vht_cap {
struct ieee80211_vht_mcs_info supp_mcs;
} __packed;
/**
* enum ieee80211_vht_chanwidth - VHT channel width
* @IEEE80211_VHT_CHANWIDTH_USE_HT: use the HT operation IE to
* determine the channel width (20 or 40 MHz)
* @IEEE80211_VHT_CHANWIDTH_80MHZ: 80 MHz bandwidth
* @IEEE80211_VHT_CHANWIDTH_160MHZ: 160 MHz bandwidth
* @IEEE80211_VHT_CHANWIDTH_80P80MHZ: 80+80 MHz bandwidth
*/
enum ieee80211_vht_chanwidth {
IEEE80211_VHT_CHANWIDTH_USE_HT = 0,
IEEE80211_VHT_CHANWIDTH_80MHZ = 1,
IEEE80211_VHT_CHANWIDTH_160MHZ = 2,
IEEE80211_VHT_CHANWIDTH_80P80MHZ = 3,
};
/**
* struct ieee80211_vht_operation - VHT operation IE
*

2
net/mac80211/ieee80211_i.h
View File

@ -371,6 +371,8 @@ enum ieee80211_sta_flags {
IEEE80211_STA_RESET_SIGNAL_AVE = BIT(9),
IEEE80211_STA_DISABLE_40MHZ = BIT(10),
IEEE80211_STA_DISABLE_VHT = BIT(11),
IEEE80211_STA_DISABLE_80P80MHZ = BIT(12),
IEEE80211_STA_DISABLE_160MHZ = BIT(13),
};
struct ieee80211_mgd_auth_data {

368
net/mac80211/mlme.c
View File

@ -354,6 +354,16 @@ static void ieee80211_add_vht_ie(struct ieee80211_sub_if_data *sdata,
/* determine capability flags */
cap = vht_cap.cap;
if (sdata->u.mgd.flags & IEEE80211_STA_DISABLE_80P80MHZ) {
cap &= ~IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ;
cap |= IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ;
}
if (sdata->u.mgd.flags & IEEE80211_STA_DISABLE_160MHZ) {
cap &= ~IEEE80211_VHT_CAP_SHORT_GI_160;
cap &= ~IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ;
}
/* reserve and fill IE */
pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
ieee80211_ie_build_vht_cap(pos, &vht_cap, cap);
@ -543,6 +553,10 @@ static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata)
offset = noffset;
}
if (WARN_ON_ONCE((ifmgd->flags & IEEE80211_STA_DISABLE_HT) &&
!(ifmgd->flags & IEEE80211_STA_DISABLE_VHT)))
ifmgd->flags |= IEEE80211_STA_DISABLE_VHT;
if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT))
ieee80211_add_ht_ie(sdata, skb, assoc_data->ap_ht_param,
sband, chan, sdata->smps_mode);
@ -3183,23 +3197,270 @@ int ieee80211_max_network_latency(struct notifier_block *nb,
return 0;
}
static u32 chandef_downgrade(struct cfg80211_chan_def *c)
{
u32 ret;
int tmp;
switch (c->width) {
case NL80211_CHAN_WIDTH_20:
c->width = NL80211_CHAN_WIDTH_20_NOHT;
ret = IEEE80211_STA_DISABLE_HT | IEEE80211_STA_DISABLE_VHT;
break;
case NL80211_CHAN_WIDTH_40:
c->width = NL80211_CHAN_WIDTH_20;
c->center_freq1 = c->chan->center_freq;
ret = IEEE80211_STA_DISABLE_40MHZ |
IEEE80211_STA_DISABLE_VHT;
break;
case NL80211_CHAN_WIDTH_80:
tmp = (30 + c->chan->center_freq - c->center_freq1)/20;
/* n_P40 */
tmp /= 2;
/* freq_P40 */
c->center_freq1 = c->center_freq1 - 20 + 40 * tmp;
c->width = NL80211_CHAN_WIDTH_40;
ret = IEEE80211_STA_DISABLE_VHT;
break;
case NL80211_CHAN_WIDTH_80P80:
c->center_freq2 = 0;
c->width = NL80211_CHAN_WIDTH_80;
ret = IEEE80211_STA_DISABLE_80P80MHZ |
IEEE80211_STA_DISABLE_160MHZ;
break;
case NL80211_CHAN_WIDTH_160:
/* n_P20 */
tmp = (70 + c->chan->center_freq - c->center_freq1)/20;
/* n_P80 */
tmp /= 4;
c->center_freq1 = c->center_freq1 - 40 + 80 * tmp;
c->width = NL80211_CHAN_WIDTH_80;
ret = IEEE80211_STA_DISABLE_80P80MHZ |
IEEE80211_STA_DISABLE_160MHZ;
break;
default:
case NL80211_CHAN_WIDTH_20_NOHT:
WARN_ON_ONCE(1);
c->width = NL80211_CHAN_WIDTH_20_NOHT;
ret = IEEE80211_STA_DISABLE_HT | IEEE80211_STA_DISABLE_VHT;
break;
}
WARN_ON_ONCE(!cfg80211_chandef_valid(c));
return ret;
}
static u32
ieee80211_determine_chantype(struct ieee80211_sub_if_data *sdata,
struct ieee80211_supported_band *sband,
struct ieee80211_channel *channel,
const struct ieee80211_ht_operation *ht_oper,
const struct ieee80211_vht_operation *vht_oper,
struct cfg80211_chan_def *chandef)
{
struct cfg80211_chan_def vht_chandef;
u32 ht_cfreq, ret;
chandef->chan = channel;
chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
chandef->center_freq1 = channel->center_freq;
chandef->center_freq2 = 0;
if (!ht_oper || !sband->ht_cap.ht_supported) {
ret = IEEE80211_STA_DISABLE_HT | IEEE80211_STA_DISABLE_VHT;
goto out;
}
chandef->width = NL80211_CHAN_WIDTH_20;
ht_cfreq = ieee80211_channel_to_frequency(ht_oper->primary_chan,
channel->band);
/* check that channel matches the right operating channel */
if (channel->center_freq != ht_cfreq) {
/*
* It's possible that some APs are confused here;
* Netgear WNDR3700 sometimes reports 4 higher than
* the actual channel in association responses, but
* since we look at probe response/beacon data here
* it should be OK.
*/
sdata_info(sdata,
"Wrong control channel: center-freq: %d ht-cfreq: %d ht->primary_chan: %d band: %d - Disabling HT\n",
channel->center_freq, ht_cfreq,
ht_oper->primary_chan, channel->band);
ret = IEEE80211_STA_DISABLE_HT | IEEE80211_STA_DISABLE_VHT;
goto out;
}
/* check 40 MHz support, if we have it */
if (sband->ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) {
switch (ht_oper->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
chandef->width = NL80211_CHAN_WIDTH_40;
chandef->center_freq1 += 10;
break;
case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
chandef->width = NL80211_CHAN_WIDTH_40;
chandef->center_freq1 -= 10;
break;
}
} else {
/* 40 MHz (and 80 MHz) must be supported for VHT */
ret = IEEE80211_STA_DISABLE_VHT;
goto out;
}
if (!vht_oper || !sband->vht_cap.vht_supported) {
ret = IEEE80211_STA_DISABLE_VHT;
goto out;
}
vht_chandef.chan = channel;
vht_chandef.center_freq1 =
ieee80211_channel_to_frequency(vht_oper->center_freq_seg1_idx,
channel->band);
vht_chandef.center_freq2 = 0;
if (vht_oper->center_freq_seg2_idx)
vht_chandef.center_freq2 =
ieee80211_channel_to_frequency(
vht_oper->center_freq_seg2_idx,
channel->band);
switch (vht_oper->chan_width) {
case IEEE80211_VHT_CHANWIDTH_USE_HT:
vht_chandef.width = chandef->width;
break;
case IEEE80211_VHT_CHANWIDTH_80MHZ:
vht_chandef.width = NL80211_CHAN_WIDTH_80;
break;
case IEEE80211_VHT_CHANWIDTH_160MHZ:
vht_chandef.width = NL80211_CHAN_WIDTH_160;
break;
case IEEE80211_VHT_CHANWIDTH_80P80MHZ:
vht_chandef.width = NL80211_CHAN_WIDTH_80P80;
break;
default:
sdata_info(sdata,
"AP VHT operation IE has invalid channel width (%d), disable VHT\n",
vht_oper->chan_width);
ret = IEEE80211_STA_DISABLE_VHT;
goto out;
}
if (!cfg80211_chandef_valid(&vht_chandef)) {
sdata_info(sdata,
"AP VHT information is invalid, disable VHT\n");
ret = IEEE80211_STA_DISABLE_VHT;
goto out;
}
if (cfg80211_chandef_identical(chandef, &vht_chandef)) {
ret = 0;
goto out;
}
if (!cfg80211_chandef_compatible(chandef, &vht_chandef)) {
sdata_info(sdata,
"AP VHT information doesn't match HT, disable VHT\n");
ret = IEEE80211_STA_DISABLE_VHT;
goto out;
}
*chandef = vht_chandef;
ret = 0;
while (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
IEEE80211_CHAN_DISABLED)) {
if (WARN_ON(chandef->width == NL80211_CHAN_WIDTH_20_NOHT)) {
ret = IEEE80211_STA_DISABLE_HT |
IEEE80211_STA_DISABLE_VHT;
goto out;
}
ret = chandef_downgrade(chandef);
}
if (chandef->width != vht_chandef.width)
sdata_info(sdata,
"local regulatory prevented using AP HT/VHT configuration, downgraded\n");
out:
WARN_ON_ONCE(!cfg80211_chandef_valid(chandef));
return ret;
}
static u8 ieee80211_ht_vht_rx_chains(struct ieee80211_sub_if_data *sdata,
struct cfg80211_bss *cbss)
{
struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
const u8 *ht_cap_ie, *vht_cap_ie;
const struct ieee80211_ht_cap *ht_cap;
const struct ieee80211_vht_cap *vht_cap;
u8 chains = 1;
if (ifmgd->flags & IEEE80211_STA_DISABLE_HT)
return chains;
ht_cap_ie = cfg80211_find_ie(WLAN_EID_HT_CAPABILITY,
cbss->information_elements,
cbss->len_information_elements);
if (ht_cap_ie && ht_cap_ie[1] >= sizeof(*ht_cap)) {
ht_cap = (void *)(ht_cap_ie + 2);
chains = ieee80211_mcs_to_chains(&ht_cap->mcs);
/*
* TODO: use "Tx Maximum Number Spatial Streams Supported" and
* "Tx Unequal Modulation Supported" fields.
*/
}
if (ifmgd->flags & IEEE80211_STA_DISABLE_VHT)
return chains;
vht_cap_ie = cfg80211_find_ie(WLAN_EID_VHT_CAPABILITY,
cbss->information_elements,
cbss->len_information_elements);
if (vht_cap_ie && vht_cap_ie[1] >= sizeof(*vht_cap)) {
u8 nss;
u16 tx_mcs_map;
vht_cap = (void *)(vht_cap_ie + 2);
tx_mcs_map = le16_to_cpu(vht_cap->supp_mcs.tx_mcs_map);
for (nss = 8; nss > 0; nss--) {
if (((tx_mcs_map >> (2 * (nss - 1))) & 3) !=
IEEE80211_VHT_MCS_NOT_SUPPORTED)
break;
}
/* TODO: use "Tx Highest Supported Long GI Data Rate" field? */
chains = max(chains, nss);
}
return chains;
}
static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata,
struct cfg80211_bss *cbss)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
int ht_cfreq;
enum nl80211_channel_type channel_type = NL80211_CHAN_NO_HT;
const u8 *ht_oper_ie;
const struct ieee80211_ht_operation *ht_oper = NULL;
const struct ieee80211_vht_operation *vht_oper = NULL;
struct ieee80211_supported_band *sband;
struct cfg80211_chan_def chandef;
int ret;
sband = local->hw.wiphy->bands[cbss->channel->band];
ifmgd->flags &= ~IEEE80211_STA_DISABLE_40MHZ;
ifmgd->flags &= ~(IEEE80211_STA_DISABLE_40MHZ |
IEEE80211_STA_DISABLE_80P80MHZ |
IEEE80211_STA_DISABLE_160MHZ);
if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT) &&
sband->ht_cap.ht_supported) {
const u8 *ht_oper_ie;
if (sband->ht_cap.ht_supported) {
ht_oper_ie = cfg80211_find_ie(WLAN_EID_HT_OPERATION,
cbss->information_elements,
cbss->len_information_elements);
@ -3207,82 +3468,45 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata,
ht_oper = (void *)(ht_oper_ie + 2);
}
if (ht_oper) {
ht_cfreq = ieee80211_channel_to_frequency(ht_oper->primary_chan,
cbss->channel->band);
/* check that channel matches the right operating channel */
if (cbss->channel->center_freq != ht_cfreq) {
/*
* It's possible that some APs are confused here;
* Netgear WNDR3700 sometimes reports 4 higher than
* the actual channel in association responses, but
* since we look at probe response/beacon data here
* it should be OK.
*/
if (!(ifmgd->flags & IEEE80211_STA_DISABLE_VHT) &&
sband->vht_cap.vht_supported) {
const u8 *vht_oper_ie;
vht_oper_ie = cfg80211_find_ie(WLAN_EID_VHT_OPERATION,
cbss->information_elements,
cbss->len_information_elements);
if (vht_oper_ie && vht_oper_ie[1] >= sizeof(*vht_oper))
vht_oper = (void *)(vht_oper_ie + 2);
if (vht_oper && !ht_oper) {
vht_oper = NULL;
sdata_info(sdata,
"Wrong control channel: center-freq: %d ht-cfreq: %d ht->primary_chan: %d band: %d - Disabling HT\n",
cbss->channel->center_freq,
ht_cfreq, ht_oper->primary_chan,
cbss->channel->band);
ht_oper = NULL;
"AP advertised VHT without HT, disabling both\n");
sdata->flags |= IEEE80211_STA_DISABLE_HT;
sdata->flags |= IEEE80211_STA_DISABLE_VHT;
}
}
if (ht_oper) {
/*
* cfg80211 already verified that the channel itself can
* be used, but it didn't check that we can do the right
* HT type, so do that here as well. If HT40 isn't allowed
* on this channel, disable 40 MHz operation.
*/
const u8 *ht_cap_ie;
const struct ieee80211_ht_cap *ht_cap;
u8 chains = 1;
ifmgd->flags |= ieee80211_determine_chantype(sdata, sband,
cbss->channel,
ht_oper, vht_oper,
&chandef);
channel_type = NL80211_CHAN_HT20;
if (sband->ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) {
switch (ht_oper->ht_param &
IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
if (cbss->channel->flags &
IEEE80211_CHAN_NO_HT40PLUS)
ifmgd->flags |=
IEEE80211_STA_DISABLE_40MHZ;
else
channel_type = NL80211_CHAN_HT40PLUS;
break;
case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
if (cbss->channel->flags &
IEEE80211_CHAN_NO_HT40MINUS)
ifmgd->flags |=
IEEE80211_STA_DISABLE_40MHZ;
else
channel_type = NL80211_CHAN_HT40MINUS;
break;
}
}
ht_cap_ie = cfg80211_find_ie(WLAN_EID_HT_CAPABILITY,
cbss->information_elements,
cbss->len_information_elements);
if (ht_cap_ie && ht_cap_ie[1] >= sizeof(*ht_cap)) {
ht_cap = (void *)(ht_cap_ie + 2);
chains = ieee80211_mcs_to_chains(&ht_cap->mcs);
}
sdata->needed_rx_chains = min(chains, local->rx_chains);
} else {
sdata->needed_rx_chains = 1;
sdata->u.mgd.flags |= IEEE80211_STA_DISABLE_HT;
}
sdata->needed_rx_chains = min(ieee80211_ht_vht_rx_chains(sdata, cbss),
local->rx_chains);
/* will change later if needed */
sdata->smps_mode = IEEE80211_SMPS_OFF;
ieee80211_vif_release_channel(sdata);
cfg80211_chandef_create(&chandef, cbss->channel, channel_type);
return ieee80211_vif_use_channel(sdata, &chandef,
IEEE80211_CHANCTX_SHARED);
/*
* If this fails (possibly due to channel context sharing
* on incompatible channels, e.g. 80+80 and 160 sharing the
* same control channel) try to use a smaller bandwidth.
*/
ret = ieee80211_vif_use_channel(sdata, &chandef,
IEEE80211_CHANCTX_SHARED);
while (ret && chandef.width != NL80211_CHAN_WIDTH_20_NOHT)
ifmgd->flags |= chandef_downgrade(&chandef);
return ret;
}
static int ieee80211_prep_connection(struct ieee80211_sub_if_data *sdata,