iwlwifi: mvm: support VHT MU-MIMO notification

When the device is in d0i3/d3 we will not receive the VHT
MU-MIMO group id management frame. Instead, firmware will
notify us upon exit on the current status and we can in turn
update mac80211. Support this notification.
While at it, also check as a precaution that the vif is indeed
the VHT MU-MIMO owner before updating the firmware.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/fw-api.h b/drivers/net/wireless/intel/iwlwifi/mvm/fw-api.h
index f432ddd..4a0fc47 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/fw-api.h
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/fw-api.h
@@ -290,6 +290,7 @@
 enum iwl_data_path_subcmd_ids {
 	UPDATE_MU_GROUPS_CMD = 0x1,
 	TRIGGER_RX_QUEUES_NOTIF_CMD = 0x2,
+	MU_GROUP_MGMT_NOTIF = 0xFE,
 	RX_QUEUES_NOTIFICATION = 0xFF,
 };
 
@@ -1965,6 +1966,18 @@
 	__le32 user_position[4];
 } __packed; /* MU_GROUP_ID_MNG_TABLE_API_S_VER_1 */
 
+/**
+ * struct iwl_mu_group_mgmt_notif - VHT MU-MIMO group id notification
+ *
+ * @membership_status: a bitmap of MU groups
+ * @user_position: the position of station in a group. If the station is in the
+ *	group then bits (group * 2) is the position -1
+ */
+struct iwl_mu_group_mgmt_notif {
+	__le32 membership_status[2];
+	__le32 user_position[4];
+} __packed; /* MU_GROUP_MNG_NTFY_API_S_VER_1 */
+
 #define MAX_STORED_BEACON_SIZE 600
 
 /**