From 7a5158ef8da70fdedeb0530faaa8128aa645be3c Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 8 Oct 2008 10:59:33 +0200 Subject: [PATCH] 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 Signed-off-by: John W. Linville --- include/net/mac80211.h | 28 +++++++++------- net/mac80211/main.c | 9 +++-- net/mac80211/mlme.c | 74 +++++++++++++++++++++++------------------- 3 files changed, 62 insertions(+), 49 deletions(-) diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 2fab5a7e5db7..d1466e7a47b8 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -180,8 +180,12 @@ enum ieee80211_bss_change { * @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 @@ struct ieee80211_rx_status { * * 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 d1c4e86b215c..c427954fe8e8 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -346,9 +346,12 @@ void ieee80211_bss_info_change_notify(struct ieee80211_sub_if_data *sdata, 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 6ad2619db85f..829995e740a7 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -568,15 +568,27 @@ static void ieee80211_sta_wmm_params(struct ieee80211_local *local, } } -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 @@ static u32 ieee80211_handle_protect_preamb(struct ieee80211_sub_if_data *sdata, 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 @@ static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata, 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 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 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 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 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) { -- 2.30.2