ucc_geth: Don't needlessly change MAC settings in adjust_link()

If PHY doesn't have an IRQ, phylib would poll for link changes, and
would call adjust_link() every second. In that case we disable and
enable the controller every second.

Let's better check if there is actually anything changed, and, if so,
change the MAC settings.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ucc_geth.c b/drivers/net/ucc_geth.c
index 7fff4c5a16934d61cfda4db6767bf1cb2b9945bc..41ad2f3697c710dd8be1e46985100e14242e218c 100644 (file)
--- a/drivers/net/ucc_geth.c
+++ b/drivers/net/ucc_geth.c
@@ -1651,25 +1651,28 @@ static void adjust_link(struct net_device *dev)
                        ugeth->oldspeed = phydev->speed;
                }
 
-               /*
-                * To change the MAC configuration we need to disable the
-                * controller. To do so, we have to either grab ugeth->lock,
-                * which is a bad idea since 'graceful stop' commands might
-                * take quite a while, or we can quiesce driver's activity.
-                */
-               ugeth_quiesce(ugeth);
-               ugeth_disable(ugeth, COMM_DIR_RX_AND_TX);
-
-               out_be32(&ug_regs->maccfg2, tempval);
-               out_be32(&uf_regs->upsmr, upsmr);
-
-               ugeth_enable(ugeth, COMM_DIR_RX_AND_TX);
-               ugeth_activate(ugeth);
-
                if (!ugeth->oldlink) {
                        new_state = 1;
                        ugeth->oldlink = 1;
                }
+
+               if (new_state) {
+                       /*
+                        * To change the MAC configuration we need to disable
+                        * the controller. To do so, we have to either grab
+                        * ugeth->lock, which is a bad idea since 'graceful
+                        * stop' commands might take quite a while, or we can
+                        * quiesce driver's activity.
+                        */
+                       ugeth_quiesce(ugeth);
+                       ugeth_disable(ugeth, COMM_DIR_RX_AND_TX);
+
+                       out_be32(&ug_regs->maccfg2, tempval);
+                       out_be32(&uf_regs->upsmr, upsmr);
+
+                       ugeth_enable(ugeth, COMM_DIR_RX_AND_TX);
+                       ugeth_activate(ugeth);
+               }
        } else if (ugeth->oldlink) {
                        new_state = 1;
                        ugeth->oldlink = 0;