[PATCH net 4/4] lan78xx: throttle tx path per usb speed

[Woojung.Huh]

Throttle TX path when slower than SUPER SPEED USB to avoid
choking CPU.

Signed-off-by: Woojung Huh <woojung....@microchip.com>
---
 drivers/net/usb/lan78xx.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index 9b95333..e0cbc5a 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -2264,7 +2264,9 @@ netdev_tx_t lan78xx_start_xmit(struct sk_buff *skb, 
struct net_device *net)
        if (skb2) {
                skb_queue_tail(&dev->txq_pend, skb2);
 
-               if (skb_queue_len(&dev->txq_pend) > 10)
+               /* throttle TX patch at slower than SUPER SPEED USB */
+               if ((dev->udev->speed < USB_SPEED_SUPER) &&
+                   (skb_queue_len(&dev->txq_pend) > 10))
                        netif_stop_queue(net);
        } else {
                netif_dbg(dev, tx_err, dev->net,
-- 
2.1.4