[PATCH 3/3] bcm63xx_enet: avoid uninitialized variable warning

[Arnd Bergmann]

gcc-7 and probably earlier versions get confused by this function
and print a harmless warning:

drivers/net/ethernet/broadcom/bcm63xx_enet.c: In function 'bcm_enet_open':
drivers/net/ethernet/broadcom/bcm63xx_enet.c:1130:3: error: 'phydev' may be 
used uninitialized in this function [-Werror=maybe-uninitialized]

This adds an initialization for the 'phydev' variable when it is unused
and changes the check to test for that NULL pointer to make it clear
that we always pass a valid pointer here.

Signed-off-by: Arnd Bergmann <a...@arndb.de>
---
 drivers/net/ethernet/broadcom/bcm63xx_enet.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bcm63xx_enet.c 
b/drivers/net/ethernet/broadcom/bcm63xx_enet.c
index 1ad904680ca6..f0a0bcb31b7e 100644
--- a/drivers/net/ethernet/broadcom/bcm63xx_enet.c
+++ b/drivers/net/ethernet/broadcom/bcm63xx_enet.c
@@ -913,6 +913,8 @@ static int bcm_enet_open(struct net_device *dev)
                priv->old_link = 0;
                priv->old_duplex = -1;
                priv->old_pause = -1;
+       } else {
+               phydev = NULL;
        }
 
        /* mask all interrupts and request them */
@@ -1083,7 +1085,7 @@ static int bcm_enet_open(struct net_device *dev)
        enet_dmac_writel(priv, priv->dma_chan_int_mask,
                         ENETDMAC_IRMASK, priv->tx_chan);
 
-       if (priv->has_phy)
+       if (phydev)
                phy_start(phydev);
        else
                bcm_enet_adjust_link(dev);
@@ -1126,7 +1128,7 @@ static int bcm_enet_open(struct net_device *dev)
        free_irq(dev->irq, dev);
 
 out_phy_disconnect:
-       if (priv->has_phy)
+       if (phydev)
                phy_disconnect(phydev);
 
        return ret;
-- 
2.9.0