From 7f878b0d96e6b3bd27d736fb2fb7e3cc94b16b26 Mon Sep 17 00:00:00 2001 From: Christian Lamparter Date: Sun, 16 Dec 2012 01:41:37 +0100 Subject: carl9170: allow P2P_GO interface creation after P2P_CLIENT Janusz Dziedzic reported that after a change in wpa_supplicant ["nl80211: Automatically use concurrent P2P if possible"], carl9170 was no longer able to host a P2P network. This patch tackles the problem by allowing GO interfaces to be registered, long after the P2P_CLIENT interface is brought up. Reported-by: Janusz Dziedzic Signed-off-by: Christian Lamparter Signed-off-by: John W. Linville --- drivers/net/wireless/ath/carl9170/main.c | 54 ++++++++++++++++++++++++++++++-- 1 file changed, 51 insertions(+), 3 deletions(-) (limited to 'drivers/net/wireless/ath/carl9170') diff --git a/drivers/net/wireless/ath/carl9170/main.c b/drivers/net/wireless/ath/carl9170/main.c index ce8ae1e6bd3b..95e4bf05e559 100644 --- a/drivers/net/wireless/ath/carl9170/main.c +++ b/drivers/net/wireless/ath/carl9170/main.c @@ -580,7 +580,7 @@ static int carl9170_op_add_interface(struct ieee80211_hw *hw, struct ieee80211_vif *vif) { struct carl9170_vif_info *vif_priv = (void *) vif->drv_priv; - struct ieee80211_vif *main_vif; + struct ieee80211_vif *main_vif, *old_main = NULL; struct ar9170 *ar = hw->priv; int vif_id = -1, err = 0; @@ -602,6 +602,15 @@ static int carl9170_op_add_interface(struct ieee80211_hw *hw, goto init; } + /* Because the AR9170 HW's MAC doesn't provide full support for + * multiple, independent interfaces [of different operation modes]. + * We have to select ONE main interface [main mode of HW], but we + * can have multiple slaves [AKA: entry in the ACK-table]. + * + * The first (from HEAD/TOP) interface in the ar->vif_list is + * always the main intf. All following intfs in this list + * are considered to be slave intfs. + */ main_vif = carl9170_get_main_vif(ar); if (main_vif) { @@ -610,6 +619,18 @@ static int carl9170_op_add_interface(struct ieee80211_hw *hw, if (vif->type == NL80211_IFTYPE_STATION) break; + /* P2P GO [master] use-case + * Because the P2P GO station is selected dynamically + * by all participating peers of a WIFI Direct network, + * the driver has be able to change the main interface + * operating mode on the fly. + */ + if (main_vif->p2p && vif->p2p && + vif->type == NL80211_IFTYPE_AP) { + old_main = main_vif; + break; + } + err = -EBUSY; rcu_read_unlock(); @@ -648,14 +669,41 @@ static int carl9170_op_add_interface(struct ieee80211_hw *hw, vif_priv->id = vif_id; vif_priv->enable_beacon = false; ar->vifs++; - list_add_tail_rcu(&vif_priv->list, &ar->vif_list); + if (old_main) { + /* We end up in here, if the main interface is being replaced. + * Put the new main interface at the HEAD of the list and the + * previous inteface will automatically become second in line. + */ + list_add_rcu(&vif_priv->list, &ar->vif_list); + } else { + /* Add new inteface. If the list is empty, it will become the + * main inteface, otherwise it will be slave. + */ + list_add_tail_rcu(&vif_priv->list, &ar->vif_list); + } rcu_assign_pointer(ar->vif_priv[vif_id].vif, vif); init: - if (carl9170_get_main_vif(ar) == vif) { + main_vif = carl9170_get_main_vif(ar); + + if (main_vif == vif) { rcu_assign_pointer(ar->beacon_iter, vif_priv); rcu_read_unlock(); + if (old_main) { + struct carl9170_vif_info *old_main_priv = + (void *) old_main->drv_priv; + /* downgrade old main intf to slave intf. + * NOTE: We are no longer under rcu_read_lock. + * But we are still holding ar->mutex, so the + * vif data [id, addr] is safe. + */ + err = carl9170_mod_virtual_mac(ar, old_main_priv->id, + old_main->addr); + if (err) + goto unlock; + } + err = carl9170_init_interface(ar, vif); if (err) goto unlock; -- cgit v1.2.3