wlcore: cancel Tx watchdog on suspend and rearm on first Tx after

Sometimes a tx_flush during suspend fails, but the FW manages to flush
out the packets during the time when the host is supsended. Cancel
the Tx-watchdog on suspend to not cause a spurious recovery on resume
for that case. Set a flag to reinit the watchdog on the first Tx after
resume, so we'll still recover if the FW is not empty and there's
indeed a problem.
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ti/wlcore/main.c

@@ -1767,6 +1767,12 @@ static int wl1271_op_suspend(struct ieee80211_hw *hw,
 	flush_work(&wl->tx_work);
 	flush_delayed_work(&wl->elp_work);
 
+	/*
+	 * Cancel the watchdog even if above tx_flush failed. We will detect
+	 * it on resume anyway.
+	 */
+	cancel_delayed_work(&wl->tx_watchdog_work);
+
 	return 0;
 }
 
@@ -1824,6 +1830,13 @@ static int wl1271_op_resume(struct ieee80211_hw *hw)
 
 out:
 	wl->wow_enabled = false;
+
+	/*
+	 * Set a flag to re-init the watchdog on the first Tx after resume.
+	 * That way we avoid possible conditions where Tx-complete interrupts
+	 * fail to arrive and we perform a spurious recovery.
+	 */
+	set_bit(WL1271_FLAG_REINIT_TX_WDOG, &wl->flags);
 	mutex_unlock(&wl->mutex);
 
 	return 0;

drivers/net/wireless/ti/wlcore/tx.c

@@ -234,8 +234,13 @@ static int wl1271_tx_allocate(struct wl1271 *wl, struct wl12xx_vif *wlvif,
 		wl->tx_blocks_available -= total_blocks;
 		wl->tx_allocated_blocks += total_blocks;
 
-		/* If the FW was empty before, arm the Tx watchdog */
-		if (wl->tx_allocated_blocks == total_blocks)
+		/*
+		 * If the FW was empty before, arm the Tx watchdog. Also do
+		 * this on the first Tx after resume, as we always cancel the
+		 * watchdog on suspend.
+		 */
+		if (wl->tx_allocated_blocks == total_blocks ||
+		    test_and_clear_bit(WL1271_FLAG_REINIT_TX_WDOG, &wl->flags))
 			wl12xx_rearm_tx_watchdog_locked(wl);
 
 		ac = wl1271_tx_get_queue(skb_get_queue_mapping(skb));

drivers/net/wireless/ti/wlcore/wlcore_i.h

@@ -240,6 +240,7 @@ enum wl12xx_flags {
 	WL1271_FLAG_VIF_CHANGE_IN_PROGRESS,
 	WL1271_FLAG_INTENDED_FW_RECOVERY,
 	WL1271_FLAG_IO_FAILED,
+	WL1271_FLAG_REINIT_TX_WDOG,
 };
 
 enum wl12xx_vif_flags {