wifi: rt2x00: fix rt2800 watchdog function

The watchdog function is broken on rt2800 series SoCs. This patch
fixes the incorrect watchdog logic to make it work again.

1. Update current wdt queue index if it's not equal to the previous
   index. Watchdog compares the current and previous queue index to
   judge if the queue hung.
2. Make sure hung_{rx,tx} 'true' status won't be override by the
   normal queue. Any queue hangs should trigger a reset action.
3. Clear the watchdog counter of all queues before resetting the
   hardware. This change may help to avoid the reset loop.
4. Change hang check function return type to bool as we only need
   to return two status, yes or no.

Signed-off-by: Shiji Yang <yangshiji66@outlook.com>
Acked-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/TYAP286MB0315BC1D83D31154924F0D39BCD1A@TYAP286MB0315.JPNP286.PROD.OUTLOOK.COM

diff --git a/drivers/net/wireless/ralink/rt2x00/rt2800lib.c b/drivers/net/wireless/ralink/rt2x00/rt2800lib.c
index 6d6ca0d7bdcab0c43db60599f2b4c14c5cfe0d78..b93cfcb1e257bd3396127e7092a1c954a9653435 100644 (file)
--- a/drivers/net/wireless/ralink/rt2x00/rt2800lib.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2800lib.c
@@ -1237,13 +1237,14 @@ void rt2800_txdone_nostatus(struct rt2x00_dev *rt2x00dev)
 }
 EXPORT_SYMBOL_GPL(rt2800_txdone_nostatus);
 
-static int rt2800_check_hung(struct data_queue *queue)
+static bool rt2800_check_hung(struct data_queue *queue)
 {
        unsigned int cur_idx = rt2800_drv_get_dma_done(queue);
 
-       if (queue->wd_idx != cur_idx)
+       if (queue->wd_idx != cur_idx) {
+               queue->wd_idx = cur_idx;
                queue->wd_count = 0;
-       else
+       } else
                queue->wd_count++;
 
        return queue->wd_count > 16;
@@ -1280,7 +1281,7 @@ void rt2800_watchdog(struct rt2x00_dev *rt2x00dev)
                case QID_MGMT:
                        if (rt2x00queue_empty(queue))
                                continue;
-                       hung_tx = rt2800_check_hung(queue);
+                       hung_tx = hung_tx || rt2800_check_hung(queue);
                        break;
                case QID_RX:
                        /* For station mode we should reactive at least
@@ -1289,7 +1290,7 @@ void rt2800_watchdog(struct rt2x00_dev *rt2x00dev)
                         */
                        if (rt2x00dev->intf_sta_count == 0)
                                continue;
-                       hung_rx = rt2800_check_hung(queue);
+                       hung_rx = hung_rx || rt2800_check_hung(queue);
                        break;
                default:
                        break;
@@ -1302,8 +1303,12 @@ void rt2800_watchdog(struct rt2x00_dev *rt2x00dev)
        if (hung_rx)
                rt2x00_warn(rt2x00dev, "Watchdog RX hung detected\n");
 
-       if (hung_tx || hung_rx)
+       if (hung_tx || hung_rx) {
+               queue_for_each(rt2x00dev, queue)
+                       queue->wd_count = 0;
+
                ieee80211_restart_hw(rt2x00dev->hw);
+       }
 }
 EXPORT_SYMBOL_GPL(rt2800_watchdog);