When HW does not support perfect filtering the feature will not be
enabled in the net_device. Add a check for this to prevent failures.

Fixes: 1b2250a04c1f ("net: stmmac: selftests: Add tests for VLAN Perfect Filtering")
Signed-off-by: Jose Abreu <Jose.Abreu@synopsys.com>

---
Cc: Giuseppe Cavallaro <redacted>
Cc: Alexandre Torgue <redacted>
Cc: Jose Abreu <redacted>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: netdev@vger.kernel.org
Cc: linux-stm32@st-md-mailman.stormreply.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Vineet Gupta <redacted>
Cc: linux-snps-arc@lists.infradead.org
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_selftests.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_selftests.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_selftests.c
index 7edee3c87ac9..450d7dac3ea6 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_selftests.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_selftests.c

@@ -971,6 +971,9 @@ static int stmmac_test_vlanfilt_perfect(struct stmmac_priv *priv)
 {
 	int ret, prev_cap = priv->dma_cap.vlhash;
 
+	if (!(priv->dev->features & NETIF_F_HW_VLAN_CTAG_FILTER))
+		return -EOPNOTSUPP;
+
 	priv->dma_cap.vlhash = 0;
 	ret = __stmmac_test_vlanfilt(priv);
 	priv->dma_cap.vlhash = prev_cap;

@@ -1063,6 +1066,9 @@ static int stmmac_test_dvlanfilt_perfect(struct stmmac_priv *priv)
 {
 	int ret, prev_cap = priv->dma_cap.vlhash;
 
+	if (!(priv->dev->features & NETIF_F_HW_VLAN_STAG_FILTER))
+		return -EOPNOTSUPP;
+
 	priv->dma_cap.vlhash = 0;
 	ret = __stmmac_test_dvlanfilt(priv);
 	priv->dma_cap.vlhash = prev_cap;

-- 
2.7.4