net: ethernet: stmmac: Fix signedness bug in ipq806x_gmac_of_parse()

[ Upstream commit 231042181dc9d6122c6faba64e99ccb25f13cc6c ]

The "gmac->phy_mode" variable is an enum and in this context GCC will
treat it as an unsigned int so the error handling will never be
triggered.

Fixes: b1c17215d718 ("stmmac: add ipq806x glue layer")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c
index 82de68b..1fc356c 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c
@@ -203,7 +203,7 @@ static void *ipq806x_gmac_of_parse(struct ipq806x_gmac *gmac)
        struct device *dev = &gmac->pdev->dev;
 
        gmac->phy_mode = of_get_phy_mode(dev->of_node);
-       if (gmac->phy_mode < 0) {
+       if ((int)gmac->phy_mode < 0) {
                dev_err(dev, "missing phy mode property\n");
                return ERR_PTR(-EINVAL);
        }