[PATCH net-next v1 3/7] net: usb: lan78xx: Improve error handling for PHY init path

Oleksij Rempel
2025-01-08T12:13:51Z

Make sure existing return values are actually used.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
---
drivers/net/usb/lan78xx.c | 58 +++++++++++++++++++++++++++------------
1 file changed, 40 insertions(+), 18 deletions(-)

diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index 3d0097d07bcd..dde127d18a07 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -2574,22 +2574,24 @@ static const struct phylink_mac_ops lan78xx_phylink_mac_ops = {

static struct phy_device *lan7801_phy_init(struct lan78xx_net *dev)
{
- u32 buf;
- int ret;
struct fixed_phy_status fphy_status = {
.link = 1,
.speed = SPEED_1000,
.duplex = DUPLEX_FULL,
};
struct phy_device *phydev;
+ int ret;

phydev = phy_find_first(dev->mdiobus);
if (!phydev) {
netdev_dbg(dev->net, "PHY Not Found!! Registering Fixed PHY\n");
phydev = fixed_phy_register(PHY_POLL, &fphy_status, NULL);
- if (IS_ERR(phydev)) {
+ if (PTR_ERR_OR_ZERO(phydev)) {
netdev_err(dev->net, "No PHY/fixed_PHY found\n");
- return NULL;
+ if (IS_ERR(phydev))
+ return phydev;
+ else
+ return ERR_PTR(-ENODEV);
}

dev->fixed_phy = phydev;
@@ -2597,24 +2599,34 @@ static struct phy_device *lan7801_phy_init(struct lan78xx_net *dev)
phydev->interface = PHY_INTERFACE_MODE_RGMII;
ret = lan78xx_write_reg(dev, MAC_RGMII_ID,
MAC_RGMII_ID_TXC_DELAY_EN_);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
ret = lan78xx_write_reg(dev, RGMII_TX_BYP_DLL, 0x3D00);
- ret = lan78xx_read_reg(dev, HW_CFG, &buf);
- buf |= HW_CFG_CLK125_EN_;
- buf |= HW_CFG_REFCLK25_EN_;
- ret = lan78xx_write_reg(dev, HW_CFG, buf);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
+ ret = lan78xx_update_reg(dev, HW_CFG, HW_CFG_CLK125_EN_ |
+ HW_CFG_REFCLK25_EN_,
+ HW_CFG_CLK125_EN_ | HW_CFG_REFCLK25_EN_);
+ if (ret < 0)
+ return ERR_PTR(ret);
} else {
if (!phydev->drv) {
netdev_err(dev->net, "no PHY driver found\n");
- return NULL;
+ return ERR_PTR(-ENODEV);
}
phydev->interface = PHY_INTERFACE_MODE_RGMII_ID;
/* The PHY driver is responsible to configure proper RGMII
* interface delays. Disable RGMII delays on MAC side.
*/
- lan78xx_write_reg(dev, MAC_RGMII_ID, 0);
+ ret = lan78xx_write_reg(dev, MAC_RGMII_ID, 0);
+ if (ret < 0)
+ return ERR_PTR(ret);

phydev->is_internal = false;
}
+
return phydev;
}

@@ -2663,9 +2675,9 @@ static int lan78xx_phy_init(struct lan78xx_net *dev)
switch (dev->chipid) {
case ID_REV_CHIP_ID_7801_:
phydev = lan7801_phy_init(dev);
- if (!phydev) {
+ if (IS_ERR(phydev)) {
netdev_err(dev->net, "lan7801: PHY Init Failed");
- return -EIO;
+ return PTR_ERR(phydev);
}
break;

@@ -2674,7 +2686,7 @@ static int lan78xx_phy_init(struct lan78xx_net *dev)
phydev = phy_find_first(dev->mdiobus);
if (!phydev) {
netdev_err(dev->net, "no PHY found\n");
- return -EIO;
+ return -ENODEV;
}
phydev->is_internal = true;
phydev->interface = PHY_INTERFACE_MODE_INTERNAL;
@@ -2682,7 +2694,7 @@ static int lan78xx_phy_init(struct lan78xx_net *dev)

default:
netdev_err(dev->net, "Unknown CHIP ID found\n");
- return -EIO;
+ return -ENODEV;
}

/* if phyirq is not set, use polling mode in phylib */
@@ -2696,10 +2708,15 @@ static int lan78xx_phy_init(struct lan78xx_net *dev)
if (ret) {
netdev_err(dev->net, "can't attach PHY to %s, error %pe\n",
dev->mdiobus->id, ERR_PTR(ret));
- return -EIO;
+ return ret;
}

- phy_suspend(phydev);
+ ret = phy_suspend(phydev);
+ if (ret) {
+ netdev_err(dev->net, "can't suspend PHY, error %pe\n",
+ ERR_PTR(ret));
+ return ret;
+ }

phy_support_eee(phydev);

@@ -2712,7 +2729,10 @@ static int lan78xx_phy_init(struct lan78xx_net *dev)
sizeof(u32));
if (len >= 0) {
/* Ensure the appropriate LEDs are enabled */
- lan78xx_read_reg(dev, HW_CFG, &reg);
+ ret = lan78xx_read_reg(dev, HW_CFG, &reg);
+ if (ret < 0)
+ return ret;
+
reg &= ~(HW_CFG_LED0_EN_ |
HW_CFG_LED1_EN_ |
HW_CFG_LED2_EN_ |
@@ -2721,7 +2741,9 @@ static int lan78xx_phy_init(struct lan78xx_net *dev)
(len > 1) * HW_CFG_LED1_EN_ |
(len > 2) * HW_CFG_LED2_EN_ |
(len > 3) * HW_CFG_LED3_EN_;
- lan78xx_write_reg(dev, HW_CFG, reg);
+ ret = lan78xx_write_reg(dev, HW_CFG, reg);
+ if (ret < 0)
+ return ret;
}
}

--
2.39.5