mac80211: fix short slot handling
This patch makes mac80211 handle short slot requests from the AP
properly. Also warn about uses of IEEE80211_CONF_SHORT_SLOT_TIME
and optimise out the code since it cannot ever be hit anyway.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 2fab5a7..d1466e7 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -180,8 +180,12 @@
* @assoc: association status
* @aid: association ID number, valid only when @assoc is true
* @use_cts_prot: use CTS protection
- * @use_short_preamble: use 802.11b short preamble
- * @use_short_slot: use short slot time (only relevant for ERP)
+ * @use_short_preamble: use 802.11b short preamble;
+ * if the hardware cannot handle this it must set the
+ * IEEE80211_HW_2GHZ_SHORT_PREAMBLE_INCAPABLE hardware flag
+ * @use_short_slot: use short slot time (only relevant for ERP);
+ * if the hardware cannot handle this it must set the
+ * IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE hardware flag
* @dtim_period: num of beacons before the next DTIM, for PSM
* @timestamp: beacon timestamp
* @beacon_int: beacon interval
@@ -442,23 +446,23 @@
*
* Flags to define PHY configuration options
*
- * @IEEE80211_CONF_SHORT_SLOT_TIME: use 802.11g short slot time
* @IEEE80211_CONF_RADIOTAP: add radiotap header at receive time (if supported)
* @IEEE80211_CONF_SUPPORT_HT_MODE: use 802.11n HT capabilities (if supported)
* @IEEE80211_CONF_PS: Enable 802.11 power save mode
*/
enum ieee80211_conf_flags {
- /*
- * TODO: IEEE80211_CONF_SHORT_SLOT_TIME will be removed once drivers
- * have been converted to use bss_info_changed() for slot time
- * configuration
- */
- IEEE80211_CONF_SHORT_SLOT_TIME = (1<<0),
- IEEE80211_CONF_RADIOTAP = (1<<1),
- IEEE80211_CONF_SUPPORT_HT_MODE = (1<<2),
- IEEE80211_CONF_PS = (1<<3),
+ IEEE80211_CONF_RADIOTAP = (1<<0),
+ IEEE80211_CONF_SUPPORT_HT_MODE = (1<<1),
+ IEEE80211_CONF_PS = (1<<2),
};
+/* XXX: remove all this once drivers stop trying to use it */
+static inline int __deprecated __IEEE80211_CONF_SHORT_SLOT_TIME(void)
+{
+ return 0;
+}
+#define IEEE80211_CONF_SHORT_SLOT_TIME (__IEEE80211_CONF_SHORT_SLOT_TIME())
+
/**
* struct ieee80211_conf - configuration of the device
*
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index d1c4e86..c427954 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -346,9 +346,12 @@
u32 ieee80211_reset_erp_info(struct ieee80211_sub_if_data *sdata)
{
- sdata->bss_conf.use_cts_prot = 0;
- sdata->bss_conf.use_short_preamble = 0;
- return BSS_CHANGED_ERP_CTS_PROT | BSS_CHANGED_ERP_PREAMBLE;
+ sdata->bss_conf.use_cts_prot = false;
+ sdata->bss_conf.use_short_preamble = false;
+ sdata->bss_conf.use_short_slot = false;
+ return BSS_CHANGED_ERP_CTS_PROT |
+ BSS_CHANGED_ERP_PREAMBLE |
+ BSS_CHANGED_ERP_SLOT;
}
void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 6ad2619..829995e 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -568,15 +568,27 @@
}
}
-static u32 ieee80211_handle_protect_preamb(struct ieee80211_sub_if_data *sdata,
- bool use_protection,
- bool use_short_preamble)
+static u32 ieee80211_handle_bss_capability(struct ieee80211_sub_if_data *sdata,
+ u16 capab, bool erp_valid, u8 erp)
{
struct ieee80211_bss_conf *bss_conf = &sdata->bss_conf;
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
struct ieee80211_if_sta *ifsta = &sdata->u.sta;
#endif
u32 changed = 0;
+ bool use_protection;
+ bool use_short_preamble;
+ bool use_short_slot;
+
+ if (erp_valid) {
+ use_protection = (erp & WLAN_ERP_USE_PROTECTION) != 0;
+ use_short_preamble = (erp & WLAN_ERP_BARKER_PREAMBLE) == 0;
+ } else {
+ use_protection = false;
+ use_short_preamble = !!(capab & WLAN_CAPABILITY_SHORT_PREAMBLE);
+ }
+
+ use_short_slot = !!(capab & WLAN_CAPABILITY_SHORT_SLOT_TIME);
if (use_protection != bss_conf->use_cts_prot) {
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
@@ -605,30 +617,18 @@
changed |= BSS_CHANGED_ERP_PREAMBLE;
}
- return changed;
-}
-
-static u32 ieee80211_handle_erp_ie(struct ieee80211_sub_if_data *sdata,
- u8 erp_value)
-{
- bool use_protection = (erp_value & WLAN_ERP_USE_PROTECTION) != 0;
- bool use_short_preamble = (erp_value & WLAN_ERP_BARKER_PREAMBLE) == 0;
-
- return ieee80211_handle_protect_preamb(sdata,
- use_protection, use_short_preamble);
-}
-
-static u32 ieee80211_handle_bss_capability(struct ieee80211_sub_if_data *sdata,
- struct ieee80211_bss *bss)
-{
- u32 changed = 0;
-
- if (bss->has_erp_value)
- changed |= ieee80211_handle_erp_ie(sdata, bss->erp_value);
- else {
- u16 capab = bss->capability;
- changed |= ieee80211_handle_protect_preamb(sdata, false,
- (capab & WLAN_CAPABILITY_SHORT_PREAMBLE) != 0);
+ if (use_short_slot != bss_conf->use_short_slot) {
+#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
+ if (net_ratelimit()) {
+ printk(KERN_DEBUG "%s: switched to %s slot"
+ " (BSSID=%s)\n",
+ sdata->dev->name,
+ use_short_slot ? "short" : "long",
+ ifsta->bssid);
+ }
+#endif
+ bss_conf->use_short_slot = use_short_slot;
+ changed |= BSS_CHANGED_ERP_SLOT;
}
return changed;
@@ -721,7 +721,8 @@
sdata->bss_conf.timestamp = bss->timestamp;
sdata->bss_conf.dtim_period = bss->dtim_period;
- changed |= ieee80211_handle_bss_capability(sdata, bss);
+ changed |= ieee80211_handle_bss_capability(sdata,
+ bss->capability, bss->has_erp_value, bss->erp_value);
ieee80211_rx_bss_put(local, bss);
}
@@ -1657,6 +1658,8 @@
struct ieee80211_local *local = sdata->local;
struct ieee80211_conf *conf = &local->hw.conf;
u32 changed = 0;
+ bool erp_valid;
+ u8 erp_value = 0;
/* Process beacon from the current BSS */
baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
@@ -1678,13 +1681,16 @@
ieee80211_sta_wmm_params(local, ifsta, elems.wmm_param,
elems.wmm_param_len);
- if (elems.erp_info && elems.erp_info_len >= 1)
- changed |= ieee80211_handle_erp_ie(sdata, elems.erp_info[0]);
- else {
- u16 capab = le16_to_cpu(mgmt->u.beacon.capab_info);
- changed |= ieee80211_handle_protect_preamb(sdata, false,
- (capab & WLAN_CAPABILITY_SHORT_PREAMBLE) != 0);
+
+ if (elems.erp_info && elems.erp_info_len >= 1) {
+ erp_valid = true;
+ erp_value = elems.erp_info[0];
+ } else {
+ erp_valid = false;
}
+ changed |= ieee80211_handle_bss_capability(sdata,
+ le16_to_cpu(mgmt->u.beacon.capab_info),
+ erp_valid, erp_value);
if (elems.ht_cap_elem && elems.ht_info_elem &&
elems.wmm_param && conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) {