smsc95xx: Configure pause time to 0xffff when tx flow control enabled

commit 9c0827317f235865ae421293f8aecf6cb327a63e upstream.

Configure pause time to 0xffff when tx flow control enabled

Set pause time to 0xffff in the pause frame to indicate the
partner to stop sending the packets. When RX buffer frees up,
the device sends pause frame with pause time zero for partner to
resume transmission.

Fixes: 2f7ca802bdae ("Add SMSC LAN9500 USB2.0 10/100 ethernet adapter driver")
Signed-off-by: Nisar Sayed <Nisar.Sayed@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c
index 6617325b14c2da86fe612dc761aefeaa84bcde4f..f1235edb403224e4b34bff70671a8e846b73fad2 100644 (file)
--- a/drivers/net/usb/smsc95xx.c
+++ b/drivers/net/usb/smsc95xx.c
@@ -419,7 +419,7 @@ static void smsc95xx_set_multicast(struct net_device *netdev)
 static void smsc95xx_phy_update_flowcontrol(struct usbnet *dev, u8 duplex,
                                            u16 lcladv, u16 rmtadv)
 {
-       u32 flow, afc_cfg = 0;
+       u32 flow = 0, afc_cfg;
 
        int ret = smsc95xx_read_reg(dev, AFC_CFG, &afc_cfg);
        if (ret < 0) {
@@ -432,20 +432,19 @@ static void smsc95xx_phy_update_flowcontrol(struct usbnet *dev, u8 duplex,
 
                if (cap & FLOW_CTRL_RX)
                        flow = 0xFFFF0002;
-               else
-                       flow = 0;
 
-               if (cap & FLOW_CTRL_TX)
+               if (cap & FLOW_CTRL_TX) {
                        afc_cfg |= 0xF;
-               else
+                       flow |= 0xFFFF0000;
+               } else {
                        afc_cfg &= ~0xF;
+               }
 
                netif_dbg(dev, link, dev->net, "rx pause %s, tx pause %s\n",
                                   cap & FLOW_CTRL_RX ? "enabled" : "disabled",
                                   cap & FLOW_CTRL_TX ? "enabled" : "disabled");
        } else {
                netif_dbg(dev, link, dev->net, "half duplex\n");
-               flow = 0;
                afc_cfg |= 0xF;
        }