ath9k: add back support for using tx99 with active monitor interfaces

Fixes controlling bitrate

Signed-off-by: Felix Fietkau <nbd@nbd.name>

package/kernel/mac80211/patches/395-ath9k-add-back-support-for-using-active-monitor-inte.patch

@@ -0,0 +1,96 @@
+From: Felix Fietkau <nbd@nbd.name>
+Date: Sat, 22 Sep 2018 15:20:50 +0200
+Subject: [PATCH] ath9k: add back support for using active monitor interfaces
+ for tx99
+
+Various documented examples on how to set up tx99 with ath9k rely
+on setting up a regular monitor interface for setting the channel.
+My previous patch "ath9k: fix tx99 with monitor mode interface" made
+it possible to set it up this way again. However, it was removing support
+for using an active monitor interface, which is required for controlling
+the bitrate as well, since the bitrate is not passed down with a regular
+monitor interface.
+
+This patch partially reverts the previous one, but keeps support for using
+a regular monitor interface to keep documented steps working in cases
+where the bitrate does not matter
+
+Fixes: d9c52fd17cb48 ("ath9k: fix tx99 with monitor mode interface")
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/drivers/net/wireless/ath/ath9k/ath9k.h
++++ b/drivers/net/wireless/ath/ath9k/ath9k.h
+@@ -1074,6 +1074,7 @@ struct ath_softc {
+ 
+ 	struct ath_spec_scan_priv spec_priv;
+ 
++	struct ieee80211_vif *tx99_vif;
+ 	struct sk_buff *tx99_skb;
+ 	bool tx99_state;
+ 	s16 tx99_power;
+--- a/drivers/net/wireless/ath/ath9k/main.c
++++ b/drivers/net/wireless/ath/ath9k/main.c
+@@ -1251,8 +1251,13 @@ static int ath9k_add_interface(struct ie
+ 	struct ath_vif *avp = (void *)vif->drv_priv;
+ 	struct ath_node *an = &avp->mcast_node;
+ 
+-	if (IS_ENABLED(CPTCFG_ATH9K_TX99))
+-		return -EOPNOTSUPP;
++	if (IS_ENABLED(CPTCFG_ATH9K_TX99)) {
++		if (sc->cur_chan->nvifs >= 1) {
++			mutex_unlock(&sc->mutex);
++			return -EOPNOTSUPP;
++		}
++		sc->tx99_vif = vif;
++	}
+ 
+ 	mutex_lock(&sc->mutex);
+ 
+@@ -1337,6 +1342,7 @@ static void ath9k_remove_interface(struc
+ 	ath9k_p2p_remove_vif(sc, vif);
+ 
+ 	sc->cur_chan->nvifs--;
++	sc->tx99_vif = NULL;
+ 	if (!ath9k_is_chanctx_enabled())
+ 		list_del(&avp->list);
+ 
+--- a/drivers/net/wireless/ath/ath9k/tx99.c
++++ b/drivers/net/wireless/ath/ath9k/tx99.c
+@@ -54,6 +54,7 @@ static struct sk_buff *ath9k_build_tx99_
+ 	struct ieee80211_hdr *hdr;
+ 	struct ieee80211_tx_info *tx_info;
+ 	struct sk_buff *skb;
++	struct ath_vif *avp;
+ 
+ 	skb = alloc_skb(len, GFP_KERNEL);
+ 	if (!skb)
+@@ -71,11 +72,17 @@ static struct sk_buff *ath9k_build_tx99_
+ 	memcpy(hdr->addr2, hw->wiphy->perm_addr, ETH_ALEN);
+ 	memcpy(hdr->addr3, hw->wiphy->perm_addr, ETH_ALEN);
+ 
++	if (sc->tx99_vif) {
++		avp = (struct ath_vif *) sc->tx99_vif->drv_priv;
++		hdr->seq_ctrl |= cpu_to_le16(avp->seq_no);
++	}
++
+ 	tx_info = IEEE80211_SKB_CB(skb);
+ 	memset(tx_info, 0, sizeof(*tx_info));
+ 	rate = &tx_info->control.rates[0];
+ 	tx_info->band = sc->cur_chan->chandef.chan->band;
+ 	tx_info->flags = IEEE80211_TX_CTL_NO_ACK;
++	tx_info->control.vif = sc->tx99_vif;
+ 	rate->count = 1;
+ 	if (ah->curchan && IS_CHAN_HT(ah->curchan)) {
+ 		rate->flags |= IEEE80211_TX_RC_MCS;
+--- a/drivers/net/wireless/ath/ath9k/xmit.c
++++ b/drivers/net/wireless/ath/ath9k/xmit.c
+@@ -2973,7 +2973,7 @@ int ath9k_tx99_send(struct ath_softc *sc
+ 		return -EINVAL;
+ 	}
+ 
+-	ath_set_rates(NULL, NULL, bf);
++	ath_set_rates(sc->tx99_vif, NULL, bf);
+ 
+ 	ath9k_hw_set_desc_link(sc->sc_ah, bf->bf_desc, bf->bf_daddr);
+ 	ath9k_hw_tx99_start(sc->sc_ah, txctl->txq->axq_qnum);