wifi: rtw88: suppress messages of failed to flush queue

Driver throws messages when scanning with a lot of traffic, because packets
in TX buffer can not be transmitted in time. Since this is a common
occurrence, change them to debug message with special debug mask that
developers can turn on this mask by default for further analysis.

Cc: Lewis Robbins <lewis.robbins2@gmail.com>
Tested-by: Lewis Robbins <lewis.robbins2@gmail.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://msgid.link/20240418002916.5965-1-pkshih@realtek.com

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

@@ -26,6 +26,7 @@ enum rtw_debug_mask {
 	RTW_DBG_STATE		= 0x00020000,
 	RTW_DBG_SDIO		= 0x00040000,
 
+	RTW_DBG_UNEXP		= 0x80000000,
 	RTW_DBG_ALL		= 0xffffffff
 };
 

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

@@ -1039,14 +1039,15 @@ static void __rtw_mac_flush_prio_queue(struct rtw_dev *rtwdev,
 		msleep(20);
 	}
 
-	/* priority queue is still not empty, throw a warning,
+	/* priority queue is still not empty, throw a debug message
 	 *
 	 * Note that if we want to flush the tx queue when having a lot of
 	 * traffic (ex, 100Mbps up), some of the packets could be dropped.
 	 * And it requires like ~2secs to flush the full priority queue.
 	 */
 	if (!drop)
-		rtw_warn(rtwdev, "timed out to flush queue %d\n", prio_queue);
+		rtw_dbg(rtwdev, RTW_DBG_UNEXP,
+			"timed out to flush queue %d\n", prio_queue);
 }
 
 static void rtw_mac_flush_prio_queues(struct rtw_dev *rtwdev,

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

@@ -729,7 +729,8 @@ static void __pci_flush_queue(struct rtw_dev *rtwdev, u8 pci_q, bool drop)
 	}
 
 	if (!drop)
-		rtw_warn(rtwdev, "timed out to flush pci tx ring[%d]\n", pci_q);
+		rtw_dbg(rtwdev, RTW_DBG_UNEXP,
+			"timed out to flush pci tx ring[%d]\n", pci_q);
 }
 
 static void __rtw_pci_flush_queues(struct rtw_dev *rtwdev, u32 pci_queues,