net: mediatek: fix mtk_pending_work

The driver supports 2 MACs. Both run on the same DMA ring. If we hit a TX
timeout we need to stop both netdevs before restarting them again. If we
don't do this, mtk_stop() wont shutdown DMA and the consecutive call to
mtk_open() wont restart DMA and enable IRQs.

Signed-off-by: John Crispin <blogic@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 20 insertions, 8 deletions

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index 7b760752d2c1..cd5d0c97f0ce 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -1432,17 +1432,29 @@ static void mtk_pending_work(struct work_struct *work)
 {
         struct mtk_mac *mac = container_of(work, struct mtk_mac, pending_work);
         struct mtk_eth *eth = mac->hw;
-        struct net_device *dev = eth->netdev[mac->id];
-        int err;
+        int err, i;
+        unsigned long restart = 0;
 
         rtnl_lock();
-        mtk_stop(dev);
 
-        err = mtk_open(dev);
-        if (err) {
-                netif_alert(eth, ifup, dev,
-                            "Driver up/down cycle failed, closing device.\n");
-                dev_close(dev);
+        /* stop all devices to make sure that dma is properly shut down */
+        for (i = 0; i < MTK_MAC_COUNT; i++) {
+                if (!netif_oper_up(eth->netdev[i]))
+                        continue;
+                mtk_stop(eth->netdev[i]);
+                __set_bit(i, &restart);
+        }
+
+        /* restart DMA and enable IRQs */
+        for (i = 0; i < MTK_MAC_COUNT; i++) {
+                if (!test_bit(i, &restart))
+                        continue;
+                err = mtk_open(eth->netdev[i]);
+                if (err) {
+                        netif_alert(eth, ifup, eth->netdev[i],
+                              "Driver up/down cycle failed, closing device.\n");
+                        dev_close(eth->netdev[i]);
+                }
         }
         rtnl_unlock();
 }