rtw88: fix idle mode flow for hw scan

Upon hw scan completion, idle mode is not re-entered. This might
increase power consumption under no link mode. Fix this by adding the
re-enter flow. We need another work for this since enter_ips waits
for c2h_work to finish, which might lead to deadlock if caller is in
the same work.

Fixes: 10d162b2 ("rtw88: 8822c: add ieee80211_ops::hw_scan")
Signed-off-by: Po-Hao Huang <phhuang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220121070813.9656-3-pkshih@realtek.com

drivers/net/wireless/realtek/rtw88/fw.c

@@ -2030,7 +2030,7 @@ void rtw_hw_scan_complete(struct rtw_dev *rtwdev, struct ieee80211_vif *vif,
 	rtwdev->hal.rcr |= BIT_CBSSID_BCN;
 	rtw_write32(rtwdev, REG_RCR, rtwdev->hal.rcr);
 
-	rtw_core_scan_complete(rtwdev, vif);
+	rtw_core_scan_complete(rtwdev, vif, true);
 
 	ieee80211_wake_queues(rtwdev->hw);
 	ieee80211_scan_completed(rtwdev->hw, &info);

drivers/net/wireless/realtek/rtw88/mac80211.c

@@ -72,6 +72,9 @@ static int rtw_ops_config(struct ieee80211_hw *hw, u32 changed)
 	struct rtw_dev *rtwdev = hw->priv;
 	int ret = 0;
 
+	/* let previous ips work finish to ensure we don't leave ips twice */
+	cancel_work_sync(&rtwdev->ips_work);
+
 	mutex_lock(&rtwdev->mutex);
 
 	rtw_leave_lps_deep(rtwdev);
@@ -614,7 +617,7 @@ static void rtw_ops_sw_scan_complete(struct ieee80211_hw *hw,
 	struct rtw_dev *rtwdev = hw->priv;
 
 	mutex_lock(&rtwdev->mutex);
-	rtw_core_scan_complete(rtwdev, vif);
+	rtw_core_scan_complete(rtwdev, vif, false);
 	mutex_unlock(&rtwdev->mutex);
 }
 

drivers/net/wireless/realtek/rtw88/main.c

@@ -272,6 +272,15 @@ static void rtw_c2h_work(struct work_struct *work)
 	}
 }
 
+static void rtw_ips_work(struct work_struct *work)
+{
+	struct rtw_dev *rtwdev = container_of(work, struct rtw_dev, ips_work);
+
+	mutex_lock(&rtwdev->mutex);
+	rtw_enter_ips(rtwdev);
+	mutex_unlock(&rtwdev->mutex);
+}
+
 static u8 rtw_acquire_macid(struct rtw_dev *rtwdev)
 {
 	unsigned long mac_id;
@@ -1339,7 +1348,8 @@ void rtw_core_scan_start(struct rtw_dev *rtwdev, struct rtw_vif *rtwvif,
 	set_bit(RTW_FLAG_SCANNING, rtwdev->flags);
 }
 
-void rtw_core_scan_complete(struct rtw_dev *rtwdev, struct ieee80211_vif *vif)
+void rtw_core_scan_complete(struct rtw_dev *rtwdev, struct ieee80211_vif *vif,
+			    bool hw_scan)
 {
 	struct rtw_vif *rtwvif = (struct rtw_vif *)vif->drv_priv;
 	u32 config = 0;
@@ -1354,6 +1364,9 @@ void rtw_core_scan_complete(struct rtw_dev *rtwdev, struct ieee80211_vif *vif)
 	rtw_vif_port_config(rtwdev, rtwvif, config);
 
 	rtw_coex_scan_notify(rtwdev, COEX_SCAN_FINISH);
+
+	if (rtwvif->net_type == RTW_NET_NO_LINK && hw_scan)
+		ieee80211_queue_work(rtwdev->hw, &rtwdev->ips_work);
 }
 
 int rtw_core_start(struct rtw_dev *rtwdev)
@@ -1919,6 +1932,7 @@ int rtw_core_init(struct rtw_dev *rtwdev)
 	INIT_DELAYED_WORK(&coex->wl_ccklock_work, rtw_coex_wl_ccklock_work);
 	INIT_WORK(&rtwdev->tx_work, rtw_tx_work);
 	INIT_WORK(&rtwdev->c2h_work, rtw_c2h_work);
+	INIT_WORK(&rtwdev->ips_work, rtw_ips_work);
 	INIT_WORK(&rtwdev->fw_recovery_work, rtw_fw_recovery_work);
 	INIT_WORK(&rtwdev->ba_work, rtw_txq_ba_work);
 	skb_queue_head_init(&rtwdev->c2h_queue);

drivers/net/wireless/realtek/rtw88/main.h

@@ -1960,6 +1960,7 @@ struct rtw_dev {
 	/* c2h cmd queue & handler work */
 	struct sk_buff_head c2h_queue;
 	struct work_struct c2h_work;
+	struct work_struct ips_work;
 	struct work_struct fw_recovery_work;
 
 	/* used to protect txqs list */
@@ -2101,7 +2102,8 @@ void rtw_tx_report_purge_timer(struct timer_list *t);
 void rtw_update_sta_info(struct rtw_dev *rtwdev, struct rtw_sta_info *si);
 void rtw_core_scan_start(struct rtw_dev *rtwdev, struct rtw_vif *rtwvif,
 			 const u8 *mac_addr, bool hw_scan);
-void rtw_core_scan_complete(struct rtw_dev *rtwdev, struct ieee80211_vif *vif);
+void rtw_core_scan_complete(struct rtw_dev *rtwdev, struct ieee80211_vif *vif,
+			    bool hw_scan);
 int rtw_core_start(struct rtw_dev *rtwdev);
 void rtw_core_stop(struct rtw_dev *rtwdev);
 int rtw_chip_info_setup(struct rtw_dev *rtwdev);