[PATCH v2] stmmac: fix check for phydev being open

[Alexey Brodkin <Alexey.Brodkin@synopsys.com>]

Current implementation via IS_ERR(phydev) may make no sense because
of_phy_attach() returns NULL on failure instead of error value.

Still for checking result of phy_connect() IS_ERR() is useful.

To address both situations we use combined IS_ERR_OR_NULL() check.

Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org
Cc: David Miller <davem@davemloft.net>
Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
---

Changes compared to v1:
 * Use IS_ERR_OR_NULL() instead of discrete checks for null and err

 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 864b476..7985d8a 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -837,7 +837,7 @@ static int stmmac_init_phy(struct net_device *dev)
 				     interface);
 	}
 
-	if (IS_ERR(phydev)) {
+	if (IS_ERR_OR_NULL(phydev)) {
 		pr_err("%s: Could not attach to PHY\n", dev->name);
 		return PTR_ERR(phydev);
 	}
-- 
2.4.3