wifi: ath12k: keep ATH12K_PEER_ML_ID_VALID set in ath12k_sta::ml_peer_id

Several pieces of host bookkeeping for MLD peer IDs encode the
same fact in different ways:

  - ath12k_sta::ml_peer_id stores the raw ID in [0, ATH12K_MAX_MLO_PEERS);
  - ath12k_dp_peer::peer_id, ath12k_dp_link_peer::ml_id and the index used
    on ath12k_dp_hw::dp_peers[] always carry the ATH12K_PEER_ML_ID_VALID
    bit (BIT(13)) when the ID is real;
  - WMI_MLO_PEER_ASSOC_PARAMS::ml_peer_id sent down to firmware is
    raw, without the bookkeeping bit.

The mismatch leaks into call sites that have to remember to OR
the bit in (ath12k_peer_create(), ath12k_mac_op_sta_state()) or
remember not to (ath12k_peer_assoc_h_mlo()).

Make ath12k_sta::ml_peer_id carry the VALID bit when valid, the same
way ath12k_dp_peer::peer_id and ath12k_dp_link_peer::ml_id do:

  - ath12k_peer_ml_alloc() OR-s the bit in once on the way out;
    the internal bitmap stays raw [0, ATH12K_MAX_MLO_PEERS);
  - ath12k_peer_create() and ath12k_mac_op_sta_state() drop the
    explicit OR;
  - ath12k_peer_assoc_h_mlo() masks the bit off when populating
    the WMI ml_peer_id;

While there, introduce ath12k_peer_ml_free() to mirror
ath12k_peer_ml_alloc(), which helps avoid code duplication.

Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c5-00302-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.115823.3

Signed-off-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Rameshkumar Sundaram <rameshkumar.sundaram@oss.qualcomm.com>
Link: https://patch.msgid.link/20260720-ath12k-fw-allocated-ml-peer-id-v2-3-630632758a80@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>

3 files changed, 28 insertions, 17 deletions

diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c
index b4df222f0c19..06f1a1ba994a 100644
--- a/drivers/net/wireless/ath/ath12k/mac.c
+++ b/drivers/net/wireless/ath/ath12k/mac.c
@@ -1282,16 +1282,15 @@ void ath12k_mac_dp_peer_cleanup(struct ath12k_hw *ah)
 	struct ath12k_dp_peer *dp_peer, *tmp;
 	struct ath12k_dp_hw *dp_hw = &ah->dp_hw;
 
+	lockdep_assert_wiphy(ah->hw->wiphy);
+
 	INIT_LIST_HEAD(&peers);
 
 	spin_lock_bh(&dp_hw->peer_lock);
 	list_for_each_entry_safe(dp_peer, tmp, &dp_hw->dp_peers_list, list) {
 		if (dp_peer->is_mlo) {
-			struct ath12k_sta *ahsta = ath12k_sta_to_ahsta(dp_peer->sta);
-
 			rcu_assign_pointer(dp_hw->dp_peers[dp_peer->peer_id], NULL);
-			clear_bit(ahsta->ml_peer_id, ah->free_ml_peer_id_map);
-			ahsta->ml_peer_id = ATH12K_MLO_PEER_ID_INVALID;
+			ath12k_peer_ml_free(ah, ath12k_sta_to_ahsta(dp_peer->sta));
 		}
 
 		list_move(&dp_peer->list, &peers);
@@ -3551,7 +3550,11 @@ static void ath12k_peer_assoc_h_mlo(struct ath12k_link_sta *arsta,
 
 	ether_addr_copy(ml->mld_addr, sta->addr);
 	ml->logical_link_idx = arsta->link_idx;
-	ml->ml_peer_id = ahsta->ml_peer_id;
+	/*
+	 * WMI_MLO_PEER_ASSOC_PARAMS expects the raw ML peer ID without
+	 * the host-side ATH12K_PEER_ML_ID_VALID bookkeeping bit.
+	 */
+	ml->ml_peer_id = ahsta->ml_peer_id & ~ATH12K_PEER_ML_ID_VALID;
 	ml->ieee_link_id = arsta->link_id;
 	ml->num_partner_links = 0;
 	ml->eml_cap = sta->eml_cap;
@@ -7268,10 +7271,8 @@ static void ath12k_mac_ml_station_remove(struct ath12k_vif *ahvif,
 		ath12k_mac_free_unassign_link_sta(ah, ahsta, link_id);
 	}
 
-	if (sta->mlo) {
-		clear_bit(ahsta->ml_peer_id, ah->free_ml_peer_id_map);
-		ahsta->ml_peer_id = ATH12K_MLO_PEER_ID_INVALID;
-	}
+	if (sta->mlo)
+		ath12k_peer_ml_free(ah, ahsta);
 }
 
 static int ath12k_mac_handle_link_sta_state(struct ieee80211_hw *hw,
@@ -7743,7 +7744,7 @@ int ath12k_mac_op_sta_state(struct ieee80211_hw *hw,
 			}
 
 			dp_params.is_mlo = true;
-			dp_params.peer_id = ahsta->ml_peer_id | ATH12K_PEER_ML_ID_VALID;
+			dp_params.peer_id = ahsta->ml_peer_id;
 		}
 
 		dp_params.sta = sta;
@@ -7880,10 +7881,8 @@ int ath12k_mac_op_sta_state(struct ieee80211_hw *hw,
 peer_delete:
 	ath12k_dp_peer_delete(&ah->dp_hw, sta->addr, sta);
 ml_peer_id_clear:
-	if (sta->mlo) {
-		clear_bit(ahsta->ml_peer_id, ah->free_ml_peer_id_map);
-		ahsta->ml_peer_id = ATH12K_MLO_PEER_ID_INVALID;
-	}
+	if (sta->mlo)
+		ath12k_peer_ml_free(ah, ahsta);
 exit:
 	/* update the state if everything went well */
 	if (!ret)
diff --git a/drivers/net/wireless/ath/ath12k/peer.c b/drivers/net/wireless/ath/ath12k/peer.c
index 2681a047d4d5..5dd7c6470219 100644
--- a/drivers/net/wireless/ath/ath12k/peer.c
+++ b/drivers/net/wireless/ath/ath12k/peer.c
@@ -230,7 +230,7 @@ int ath12k_peer_create(struct ath12k *ar, struct ath12k_link_vif *arvif,
 		/* Fill ML info into created peer */
 		if (sta->mlo) {
 			ml_peer_id = ahsta->ml_peer_id;
-			peer->ml_id = ml_peer_id | ATH12K_PEER_ML_ID_VALID;
+			peer->ml_id = ml_peer_id;
 			ether_addr_copy(peer->ml_addr, sta->addr);
 
 			/* the assoc link is considered primary for now */
@@ -276,9 +276,20 @@ u16 ath12k_peer_ml_alloc(struct ath12k_hw *ah)
 	}
 
 	if (ml_peer_id == ATH12K_MAX_MLO_PEERS)
-		ml_peer_id = ATH12K_MLO_PEER_ID_INVALID;
+		return ATH12K_MLO_PEER_ID_INVALID;
 
-	return ml_peer_id;
+	return ml_peer_id | ATH12K_PEER_ML_ID_VALID;
+}
+
+void ath12k_peer_ml_free(struct ath12k_hw *ah, struct ath12k_sta *ahsta)
+{
+	lockdep_assert_wiphy(ah->hw->wiphy);
+
+	if (ahsta->ml_peer_id <
+	    (ATH12K_MAX_MLO_PEERS | ATH12K_PEER_ML_ID_VALID))
+		clear_bit(ahsta->ml_peer_id & ~ATH12K_PEER_ML_ID_VALID,
+			  ah->free_ml_peer_id_map);
+	ahsta->ml_peer_id = ATH12K_MLO_PEER_ID_INVALID;
 }
 
 int ath12k_peer_mlo_link_peers_delete(struct ath12k_vif *ahvif, struct ath12k_sta *ahsta)
diff --git a/drivers/net/wireless/ath/ath12k/peer.h b/drivers/net/wireless/ath/ath12k/peer.h
index 49d89796bc46..0f7f25b8e89c 100644
--- a/drivers/net/wireless/ath/ath12k/peer.h
+++ b/drivers/net/wireless/ath/ath12k/peer.h
@@ -26,4 +26,5 @@ int ath12k_link_sta_rhash_add(struct ath12k_base *ab, struct ath12k_link_sta *ar
 struct ath12k_link_sta *ath12k_link_sta_find_by_addr(struct ath12k_base *ab,
 						     const u8 *addr);
 u16 ath12k_peer_ml_alloc(struct ath12k_hw *ah);
+void ath12k_peer_ml_free(struct ath12k_hw *ah, struct ath12k_sta *ahsta);
 #endif /* _PEER_H_ */