[PATCH v2 3/3] wifi: rt2x00: restart beacon queue when hardware reset

[Shiji Yang <yangshiji66@outlook.com>]

When a hardware reset is triggered, all registers are reset, so all
queues are forced to stop in hardware interface. However, mac80211
will not automatically stop the queue. If we don't manually stop the
beacon queue, the queue will be deadlocked and unable to start again.
This patch fixes the issue where Apple devices cannot connect to the
AP after calling ieee80211_restart_hw().

Signed-off-by: Shiji Yang <yangshiji66@outlook.com>
Acked-by: Stanislaw Gruszka <stf_xl@wp.pl>
---
 drivers/net/wireless/ralink/rt2x00/rt2x00dev.c |  3 +++
 drivers/net/wireless/ralink/rt2x00/rt2x00mac.c | 11 +++++++++++
 2 files changed, 14 insertions(+)

diff --git a/drivers/net/wireless/ralink/rt2x00/rt2x00dev.c b/drivers/net/wireless/ralink/rt2x00/rt2x00dev.c
index 9a9cfd0ce..00b945053 100644
--- a/drivers/net/wireless/ralink/rt2x00/rt2x00dev.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2x00dev.c
@@ -101,6 +101,7 @@ void rt2x00lib_disable_radio(struct rt2x00_dev *rt2x00dev)
 	rt2x00link_stop_tuner(rt2x00dev);
 	rt2x00queue_stop_queues(rt2x00dev);
 	rt2x00queue_flush_queues(rt2x00dev, true);
+	rt2x00queue_stop_queue(rt2x00dev->bcn);
 
 	/*
 	 * Disable radio.
@@ -1286,6 +1287,7 @@ int rt2x00lib_start(struct rt2x00_dev *rt2x00dev)
 	rt2x00dev->intf_ap_count = 0;
 	rt2x00dev->intf_sta_count = 0;
 	rt2x00dev->intf_associated = 0;
+	rt2x00dev->intf_beaconing = 0;
 
 	/* Enable the radio */
 	retval = rt2x00lib_enable_radio(rt2x00dev);
@@ -1312,6 +1314,7 @@ void rt2x00lib_stop(struct rt2x00_dev *rt2x00dev)
 	rt2x00dev->intf_ap_count = 0;
 	rt2x00dev->intf_sta_count = 0;
 	rt2x00dev->intf_associated = 0;
+	rt2x00dev->intf_beaconing = 0;
 }
 
 static inline void rt2x00lib_set_if_combinations(struct rt2x00_dev *rt2x00dev)
diff --git a/drivers/net/wireless/ralink/rt2x00/rt2x00mac.c b/drivers/net/wireless/ralink/rt2x00/rt2x00mac.c
index 4202c6517..75fda72c1 100644
--- a/drivers/net/wireless/ralink/rt2x00/rt2x00mac.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2x00mac.c
@@ -598,6 +598,17 @@ void rt2x00mac_bss_info_changed(struct ieee80211_hw *hw,
 	 */
 	if (changes & BSS_CHANGED_BEACON_ENABLED) {
 		mutex_lock(&intf->beacon_skb_mutex);
+
+		/*
+		 * Clear the 'enable_beacon' flag and clear beacon because
+		 * the beacon queue has been stopped after hardware reset.
+		 */
+		if (test_bit(DEVICE_STATE_RESET, &rt2x00dev->flags) &&
+		    intf->enable_beacon) {
+			intf->enable_beacon = false;
+			rt2x00queue_clear_beacon(rt2x00dev, vif);
+		}
+
 		if (!bss_conf->enable_beacon && intf->enable_beacon) {
 			rt2x00dev->intf_beaconing--;
 			intf->enable_beacon = false;
-- 
2.39.2