net: of_get_phy_mode: Change API to solve int/unit warnings

Before this change of_get_phy_mode() returned an enum,
phy_interface_t. On error, -ENODEV etc, is returned. If the result of
the function is stored in a variable of type phy_interface_t, and the
compiler has decided to represent this as an unsigned int, comparision
with -ENODEV etc, is a signed vs unsigned comparision.

Fix this problem by changing the API. Make the function return an
error, or 0 on success, and pass a pointer, of type phy_interface_t,
where the phy mode should be stored.

v2:
Return with *interface set to PHY_INTERFACE_MODE_NA on error.
Add error checks to all users of of_get_phy_mode()
Fixup a few reverse christmas tree errors
Fixup a few slightly malformed reverse christmas trees

v3:
Fix 0-day reported errors.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 3 deletions

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c
index 306da8f6b7d5..bd6c01004913 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c
@@ -338,10 +338,9 @@ static int meson8b_dwmac_probe(struct platform_device *pdev)
 	}
 
 	dwmac->dev = &pdev->dev;
-	dwmac->phy_mode = of_get_phy_mode(pdev->dev.of_node);
-	if ((int)dwmac->phy_mode < 0) {
+	ret = of_get_phy_mode(pdev->dev.of_node, &dwmac->phy_mode);
+	if (ret) {
 		dev_err(&pdev->dev, "missing phy-mode property\n");
-		ret = -EINVAL;
 		goto err_remove_config_dt;
 	}