iwlwifi: mvm: implement mac80211 TDLS channel-switch APIs

Maintain a TDLS channel-switch state and update it according to
notifications from FW and timeouts. Explicitly check all state
transitions are valid.
When switching is initiated by mac80211, use a delayed work to
periodically reschedule it from iwlwifi.
Give the FW mac80211 generated TDLS channel-switch request/response
templates. It will change appropriate values (switch timings) and Tx
them at appropriate times.

Enable the channel switch wiphy capability bit when the FW supports it.
Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

drivers/net/wireless/iwlwifi/mvm/fw.c

@@ -466,6 +466,8 @@ int iwl_mvm_up(struct iwl_mvm *mvm)
 	for (i = 0; i < IWL_MVM_STATION_COUNT; i++)
 		RCU_INIT_POINTER(mvm->fw_id_to_mac_id[i], NULL);
 
+	mvm->tdls_cs.peer.sta_id = IWL_MVM_STATION_COUNT;
+
 	/* reset quota debouncing buffer - 0xff will yield invalid data */
 	memset(&mvm->last_quota_cmd, 0xff, sizeof(mvm->last_quota_cmd));
 

drivers/net/wireless/iwlwifi/mvm/mac80211.c

@@ -495,6 +495,12 @@ int iwl_mvm_mac_setup_register(struct iwl_mvm *mvm)
 		hw->wiphy->flags |= WIPHY_FLAG_SUPPORTS_TDLS;
 	}
 
+	if (mvm->fw->ucode_capa.capa[0] &
+	    IWL_UCODE_TLV_CAPA_TDLS_CHANNEL_SWITCH) {
+		IWL_DEBUG_TDLS(mvm, "TDLS channel switch supported\n");
+		hw->wiphy->features |= NL80211_FEATURE_TDLS_CHANNEL_SWITCH;
+	}
+
 	ret = ieee80211_register_hw(mvm->hw);
 	if (ret)
 		iwl_mvm_leds_exit(mvm);
@@ -3211,6 +3217,10 @@ const struct ieee80211_ops iwl_mvm_hw_ops = {
 
 	.channel_switch_beacon = iwl_mvm_channel_switch_beacon,
 
+	.tdls_channel_switch = iwl_mvm_tdls_channel_switch,
+	.tdls_cancel_channel_switch = iwl_mvm_tdls_cancel_channel_switch,
+	.tdls_recv_channel_switch = iwl_mvm_tdls_recv_channel_switch,
+
 	CFG80211_TESTMODE_CMD(iwl_mvm_mac_testmode_cmd)
 
 #ifdef CONFIG_PM_SLEEP

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

@@ -519,6 +519,13 @@ enum {
 #define IWL_MVM_DEBUG_SET_TEMPERATURE_MIN -100
 #define IWL_MVM_DEBUG_SET_TEMPERATURE_MAX 200
 
+enum iwl_mvm_tdls_cs_state {
+	IWL_MVM_TDLS_SW_IDLE = 0,
+	IWL_MVM_TDLS_SW_REQ_SENT,
+	IWL_MVM_TDLS_SW_REQ_RCVD,
+	IWL_MVM_TDLS_SW_ACTIVE,
+};
+
 struct iwl_mvm {
 	/* for logger access */
 	struct device *dev;
@@ -740,6 +747,28 @@ struct iwl_mvm {
 	u32 ap_last_beacon_gp2;
 
 	u8 low_latency_agg_frame_limit;
+
+	/* TDLS channel switch data */
+	struct {
+		struct delayed_work dwork;
+		enum iwl_mvm_tdls_cs_state state;
+
+		/*
+		 * Current cs sta - might be different from periodic cs peer
+		 * station. Value is meaningless when the cs-state is idle.
+		 */
+		u8 cur_sta_id;
+
+		/* TDLS periodic channel-switch peer */
+		struct {
+			u8 sta_id;
+			u8 op_class;
+			bool initiator; /* are we the link initiator */
+			struct cfg80211_chan_def chandef;
+			struct sk_buff *skb; /* ch sw template */
+			u32 ch_sw_tm_ie;
+		} peer;
+	} tdls_cs;
 };
 
 /* Extract MVM priv from op_mode and _hw */
@@ -1258,6 +1287,20 @@ void iwl_mvm_recalc_tdls_state(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
 			       bool sta_added);
 void iwl_mvm_mac_mgd_protect_tdls_discover(struct ieee80211_hw *hw,
 					   struct ieee80211_vif *vif);
+int iwl_mvm_tdls_channel_switch(struct ieee80211_hw *hw,
+				struct ieee80211_vif *vif,
+				struct ieee80211_sta *sta, u8 oper_class,
+				struct cfg80211_chan_def *chandef,
+				struct sk_buff *tmpl_skb, u32 ch_sw_tm_ie);
+void iwl_mvm_tdls_recv_channel_switch(struct ieee80211_hw *hw,
+				      struct ieee80211_vif *vif,
+				      struct ieee80211_tdls_ch_sw_params *params);
+void iwl_mvm_tdls_cancel_channel_switch(struct ieee80211_hw *hw,
+					struct ieee80211_vif *vif,
+					struct ieee80211_sta *sta);
+int iwl_mvm_rx_tdls_notif(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb,
+			  struct iwl_device_cmd *cmd);
+void iwl_mvm_tdls_ch_switch_work(struct work_struct *work);
 
 struct ieee80211_vif *iwl_mvm_get_bss_vif(struct iwl_mvm *mvm);
 

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

@@ -258,6 +258,9 @@ static const struct iwl_rx_handlers iwl_mvm_rx_handlers[] = {
 		   iwl_mvm_power_uapsd_misbehaving_ap_notif, false),
 	RX_HANDLER(DTS_MEASUREMENT_NOTIFICATION, iwl_mvm_temp_notif, true),
 
+	RX_HANDLER(TDLS_CHANNEL_SWITCH_NOTIFICATION, iwl_mvm_rx_tdls_notif,
+		   true),
+
 };
 #undef RX_HANDLER
 #define CMD(x) [x] = #x
@@ -453,6 +456,7 @@ iwl_op_mode_mvm_start(struct iwl_trans *trans, const struct iwl_cfg *cfg,
 	INIT_WORK(&mvm->sta_drained_wk, iwl_mvm_sta_drained_wk);
 	INIT_WORK(&mvm->d0i3_exit_work, iwl_mvm_d0i3_exit_work);
 	INIT_WORK(&mvm->fw_error_dump_wk, iwl_mvm_fw_error_dump_wk);
+	INIT_DELAYED_WORK(&mvm->tdls_cs.dwork, iwl_mvm_tdls_ch_switch_work);
 
 	spin_lock_init(&mvm->d0i3_tx_lock);
 	spin_lock_init(&mvm->refs_lock);

drivers/net/wireless/iwlwifi/mvm/sta.c

@@ -503,6 +503,15 @@ int iwl_mvm_rm_sta(struct iwl_mvm *mvm,
 			mvm->d0i3_ap_sta_id = IWL_MVM_STATION_COUNT;
 	}
 
+	/*
+	 * This shouldn't happen - the TDLS channel switch should be canceled
+	 * before the STA is removed.
+	 */
+	if (WARN_ON_ONCE(mvm->tdls_cs.peer.sta_id == mvm_sta->sta_id)) {
+		mvm->tdls_cs.peer.sta_id = IWL_MVM_STATION_COUNT;
+		cancel_delayed_work(&mvm->tdls_cs.dwork);
+	}
+
 	/*
 	 * Make sure that the tx response code sees the station as -EBUSY and
 	 * calls the drain worker.