[PATCH 7/8] wifi: ath12k: allocate new links in change_vif_links()

[Aditya Kumar Singh]

Currently, links in an interface are allocated during channel assignment
via assign_vif_chanctx(). Conversely, links are deleted during channel
unassignment via unassign_vif_chanctx(). However, deleting links during
channel unassignment does not comply with mac80211 link handling.
Therefore, this process should be managed within change_vif_links(). To
maintain symmetry, link addition should also be handled in
change_vif_links().

Hence, add changes to allocate link arvif in change_vif_links(). Creating
the link interface on firmware will still be done during channel
assignment.

And since link will be created but channel might not be assigned, there is
a need now to test is_created flag in ath12k_mac_mlo_get_vdev_args() before
accessing link_conf or else link bring up will fail.

A subsequent change will handle link removal part.

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.3.1-00173-QCAHKSWPL_SILICONZ-1

Signed-off-by: Aditya Kumar Singh <aditya.kumar.singh@xxxxxxxxxxxxxxxx>
---
 drivers/net/wireless/ath/ath12k/mac.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c
index 5d80bbb664ea6a710eedd7b57db3523df9c893e6..b9017002f3efb27d917f0aa35a0ecc66af18ec99 100644
--- a/drivers/net/wireless/ath/ath12k/mac.c
+++ b/drivers/net/wireless/ath/ath12k/mac.c
@@ -3576,6 +3576,31 @@ ath12k_mac_op_change_vif_links(struct ieee80211_hw *hw,
 			       u16 old_links, u16 new_links,
 			       struct ieee80211_bss_conf *ol[IEEE80211_MLD_MAX_NUM_LINKS])
 {
+	struct ath12k_vif *ahvif = ath12k_vif_to_ahvif(vif);
+	unsigned long to_add = ~old_links & new_links;
+	struct ath12k_hw *ah = ath12k_hw_to_ah(hw);
+	struct ath12k_link_vif *arvif;
+	u8 link_id;
+
+	lockdep_assert_wiphy(hw->wiphy);
+
+	ath12k_generic_dbg(ATH12K_DBG_MAC,
+			   "mac vif link changed for MLD %pM old_links 0x%x new_links 0x%x\n",
+			   vif->addr, old_links, new_links);
+
+	for_each_set_bit(link_id, &to_add, IEEE80211_MLD_MAX_NUM_LINKS) {
+		arvif = wiphy_dereference(hw->wiphy, ahvif->link[link_id]);
+		/* mac80211 wants to add link but driver already has the
+		 * link. This should not happen ideally.
+		 */
+		if (WARN_ON(arvif))
+			return -EINVAL;
+
+		arvif = ath12k_mac_assign_link_vif(ah, vif, link_id);
+		if (WARN_ON(!arvif))
+			return -EINVAL;
+	}
+
 	return 0;
 }
 
@@ -8765,6 +8790,9 @@ ath12k_mac_mlo_get_vdev_args(struct ath12k_link_vif *arvif,
 		if (arvif == arvif_p)
 			continue;
 
+		if (!arvif_p->is_created)
+			continue;
+
 		link_conf = wiphy_dereference(ahvif->ah->hw->wiphy,
 					      ahvif->vif->link_conf[arvif_p->link_id]);
 

-- 
2.34.1