mac80211: introduce beacon-only timing data

In order to be able to predict the next DTIM TBTT
in the driver, add the ability to use timing data
from beacons only with the new hardware flag
IEEE80211_HW_TIMING_BEACON_ONLY and the BSS info
value sync_dtim_count which is only valid if the
timing data came from a beacon. The data can only
come from a beacon, and if no beacon was received
before association it is updated later together
with the DTIM count notification.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Johannes Berg
2013-02-05 17:48:40 +01:00
parent 8cef2c9df8
commit ef429dadf3
5 changed files with 81 additions and 7 deletions

View File

@@ -86,7 +86,7 @@ struct ieee80211_fragment_entry {
struct ieee80211_bss {
u32 device_ts;
u32 device_ts_beacon, device_ts_presp;
bool wmm_used;
bool uapsd_supported;

View File

@@ -2567,6 +2567,17 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
ifmgd->assoc_data->have_beacon = true;
ifmgd->assoc_data->need_beacon = false;
if (local->hw.flags & IEEE80211_HW_TIMING_BEACON_ONLY) {
sdata->vif.bss_conf.sync_tsf =
le64_to_cpu(mgmt->u.beacon.timestamp);
sdata->vif.bss_conf.sync_device_ts =
rx_status->device_timestamp;
if (elems.tim)
sdata->vif.bss_conf.sync_dtim_count =
elems.tim->dtim_count;
else
sdata->vif.bss_conf.sync_dtim_count = 0;
}
/* continue assoc process */
ifmgd->assoc_data->timeout = jiffies;
run_again(ifmgd, ifmgd->assoc_data->timeout);
@@ -2725,7 +2736,7 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
/*
* If we haven't had a beacon before, tell the driver about the
* DTIM period now.
* DTIM period (and beacon timing if desired) now.
*/
if (!bss_conf->dtim_period) {
/* a few bogus AP send dtim_period = 0 or no TIM IE */
@@ -2733,6 +2744,19 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
bss_conf->dtim_period = elems.tim->dtim_period ?: 1;
else
bss_conf->dtim_period = 1;
if (local->hw.flags & IEEE80211_HW_TIMING_BEACON_ONLY) {
sdata->vif.bss_conf.sync_tsf =
le64_to_cpu(mgmt->u.beacon.timestamp);
sdata->vif.bss_conf.sync_device_ts =
rx_status->device_timestamp;
if (elems.tim)
sdata->vif.bss_conf.sync_dtim_count =
elems.tim->dtim_count;
else
sdata->vif.bss_conf.sync_dtim_count = 0;
}
changed |= BSS_CHANGED_DTIM_PERIOD;
}
@@ -3712,10 +3736,33 @@ static int ieee80211_prep_connection(struct ieee80211_sub_if_data *sdata,
/* set timing information */
sdata->vif.bss_conf.beacon_int = cbss->beacon_interval;
rcu_read_lock();
ies = rcu_dereference(cbss->ies);
sdata->vif.bss_conf.sync_tsf = ies->tsf;
ies = rcu_dereference(cbss->beacon_ies);
if (ies) {
const u8 *tim_ie;
sdata->vif.bss_conf.sync_tsf = ies->tsf;
sdata->vif.bss_conf.sync_device_ts =
bss->device_ts_beacon;
tim_ie = cfg80211_find_ie(WLAN_EID_TIM,
ies->data, ies->len);
if (tim_ie && tim_ie[1] >= 2)
sdata->vif.bss_conf.sync_dtim_count = tim_ie[2];
else
sdata->vif.bss_conf.sync_dtim_count = 0;
} else if (!(local->hw.flags &
IEEE80211_HW_TIMING_BEACON_ONLY)) {
ies = rcu_dereference(cbss->proberesp_ies);
/* must be non-NULL since beacon IEs were NULL */
sdata->vif.bss_conf.sync_tsf = ies->tsf;
sdata->vif.bss_conf.sync_device_ts =
bss->device_ts_presp;
sdata->vif.bss_conf.sync_dtim_count = 0;
} else {
sdata->vif.bss_conf.sync_tsf = 0;
sdata->vif.bss_conf.sync_device_ts = 0;
sdata->vif.bss_conf.sync_dtim_count = 0;
}
rcu_read_unlock();
sdata->vif.bss_conf.sync_device_ts = bss->device_ts;
/* tell driver about BSSID, basic rates and timing */
ieee80211_bss_info_change_notify(sdata,
@@ -4041,13 +4088,23 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata,
const u8 *tim_ie = cfg80211_find_ie(WLAN_EID_TIM,
beacon_ies->data,
beacon_ies->len);
u8 dtim_count = 0;
if (tim_ie && tim_ie[1] >= sizeof(struct ieee80211_tim_ie)) {
const struct ieee80211_tim_ie *tim;
tim = (void *)(tim_ie + 2);
ifmgd->dtim_period = tim->dtim_period;
dtim_count = tim->dtim_count;
}
assoc_data->have_beacon = true;
assoc_data->timeout = jiffies;
if (local->hw.flags & IEEE80211_HW_TIMING_BEACON_ONLY) {
sdata->vif.bss_conf.sync_tsf = beacon_ies->tsf;
sdata->vif.bss_conf.sync_device_ts =
bss->device_ts_beacon;
sdata->vif.bss_conf.sync_dtim_count = dtim_count;
}
} else {
assoc_data->timeout = jiffies;
}

View File

@@ -80,7 +80,10 @@ ieee80211_bss_info_update(struct ieee80211_local *local,
bss = (void *)cbss->priv;
bss->device_ts = rx_status->device_timestamp;
if (beacon)
bss->device_ts_beacon = rx_status->device_timestamp;
else
bss->device_ts_presp = rx_status->device_timestamp;
if (elems->parse_error) {
if (beacon)

View File

@@ -340,6 +340,7 @@ TRACE_EVENT(drv_bss_info_changed,
__field(u16, assoc_cap)
__field(u64, sync_tsf)
__field(u32, sync_device_ts)
__field(u8, sync_dtim_count)
__field(u32, basic_rates)
__array(int, mcast_rate, IEEE80211_NUM_BANDS)
__field(u16, ht_operation_mode)
@@ -379,6 +380,7 @@ TRACE_EVENT(drv_bss_info_changed,
__entry->assoc_cap = info->assoc_capability;
__entry->sync_tsf = info->sync_tsf;
__entry->sync_device_ts = info->sync_device_ts;
__entry->sync_dtim_count = info->sync_dtim_count;
__entry->basic_rates = info->basic_rates;
memcpy(__entry->mcast_rate, info->mcast_rate,
sizeof(__entry->mcast_rate));