iwlwifi: mvm: allow to disable beacon filtering for AP/GO interface

When in AP mode we need to filter in beacons from other APs to update HT
operation mode. As a power optimization the beacons are filtered out when
there are no associated stations. As a result, when there are no
associated stations, we will not update the HT operation mode until a
station connects.
Add a debugfs parameter that allows to disable this optimization.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c

@@ -1548,6 +1548,9 @@ int iwl_mvm_dbgfs_register(struct iwl_mvm *mvm, struct dentry *dbgfs_dir)
 				 mvm->debugfs_dir,
 				 &mvm->scan_iter_notif_enabled))
 		goto err;
+	if (!debugfs_create_bool("drop_bcn_ap_mode", S_IRUSR | S_IWUSR,
+				 mvm->debugfs_dir, &mvm->drop_bcn_ap_mode))
+		goto err;
 
 #ifdef CONFIG_IWLWIFI_BCAST_FILTERING
 	if (mvm->fw->ucode_capa.flags & IWL_UCODE_TLV_FLAGS_BCAST_FILTERING) {

drivers/net/wireless/intel/iwlwifi/mvm/mac-ctxt.c

@@ -744,7 +744,7 @@ static void iwl_mvm_mac_ctxt_cmd_common(struct iwl_mvm *mvm,
 		 * wake-ups.
 		 */
 		cmd->filter_flags |= cpu_to_le32(MAC_FILTER_IN_PROBE_REQUEST);
-		if (mvmvif->ap_assoc_sta_count) {
+		if (mvmvif->ap_assoc_sta_count || !mvm->drop_bcn_ap_mode) {
 			cmd->filter_flags |= cpu_to_le32(MAC_FILTER_IN_BEACON);
 			IWL_DEBUG_HC(mvm, "Asking FW to pass beacons\n");
 		} else {

drivers/net/wireless/intel/iwlwifi/mvm/mvm.h

@@ -859,6 +859,12 @@ struct iwl_mvm {
 
 	u32 ciphers[6];
 	struct iwl_mvm_tof_data tof_data;
+
+	/*
+	 * Drop beacons from other APs in AP mode when there are no connected
+	 * clients.
+	 */
+	bool drop_bcn_ap_mode;
 };
 
 /* Extract MVM priv from op_mode and _hw */

drivers/net/wireless/intel/iwlwifi/mvm/ops.c

@@ -492,6 +492,7 @@ iwl_op_mode_mvm_start(struct iwl_trans *trans, const struct iwl_cfg *cfg,
 	}
 	mvm->sf_state = SF_UNINIT;
 	mvm->cur_ucode = IWL_UCODE_INIT;
+	mvm->drop_bcn_ap_mode = true;
 
 	mutex_init(&mvm->mutex);
 	mutex_init(&mvm->d0i3_suspend_mutex);