[PATCH] net: macb: fix for fixed-link mode

From: Milind Parab
Date: Sun Jan 12 2020 - 22:27:32 EST


This patch fix the issue with fixed link. With fixed-link
device opening fails due to macb_phylink_connect not
handling fixed-link mode, in which case no MAC-PHY connection
is needed and phylink_connect return success (0), however
in current driver attempt is made to search and connect to
PHY even for fixed-link.

Fixes: 7897b071ac3b ("net: macb: convert to phylink")
Signed-off-by: Milind Parab <mparab@xxxxxxxxxxx>
---
Changes in v2:
1. Code refactoring to remove extra if condition

Changes in v3:
1. Reverse christmas tree ordering of local variables
---
drivers/net/ethernet/cadence/macb_main.c | 30 ++++++++++++++----------
1 file changed, 17 insertions(+), 13 deletions(-)

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 1c547ee0d444..7a2fe63d1136 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -650,21 +650,24 @@ static const struct phylink_mac_ops macb_phylink_ops = {
.mac_link_up = macb_mac_link_up,
};

+static bool macb_phy_handle_exists(struct device_node *dn)
+{
+ dn = of_parse_phandle(dn, "phy-handle", 0);
+ of_node_put(dn);
+ return dn != NULL;
+}
+
static int macb_phylink_connect(struct macb *bp)
{
+ struct device_node *dn = bp->pdev->dev.of_node;
struct net_device *dev = bp->dev;
struct phy_device *phydev;
int ret;

- if (bp->pdev->dev.of_node &&
- of_parse_phandle(bp->pdev->dev.of_node, "phy-handle", 0)) {
- ret = phylink_of_phy_connect(bp->phylink, bp->pdev->dev.of_node,
- 0);
- if (ret) {
- netdev_err(dev, "Could not attach PHY (%d)\n", ret);
- return ret;
- }
- } else {
+ if (dn)
+ ret = phylink_of_phy_connect(bp->phylink, dn, 0);
+
+ if (!dn || (ret && !macb_phy_handle_exists(dn))) {
phydev = phy_find_first(bp->mii_bus);
if (!phydev) {
netdev_err(dev, "no PHY found\n");
@@ -673,10 +676,11 @@ static int macb_phylink_connect(struct macb *bp)

/* attach the mac to the phy */
ret = phylink_connect_phy(bp->phylink, phydev);
- if (ret) {
- netdev_err(dev, "Could not attach to PHY (%d)\n", ret);
- return ret;
- }
+ }
+
+ if (ret) {
+ netdev_err(dev, "Could not attach PHY (%d)\n", ret);
+ return ret;
}

phylink_start(bp->phylink);
--
2.17.1