[PATCH net-next v2 3/7] net: usb: lan78xx: Improve error handling for PHY init path

From: Oleksij Rempel
Date: Fri Mar 07 2025 - 13:24:50 EST


Make sure existing return values are actually used.

Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
---
drivers/net/usb/lan78xx.c | 45 ++++++++++++++++++++++++++++-----------
1 file changed, 32 insertions(+), 13 deletions(-)

diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index 4efe7a956667..68ca507b6412 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -2569,31 +2569,40 @@ static struct phy_device *lan7801_phy_init(struct lan78xx_net *dev)
{
struct phy_device *phydev;
int ret;
- u32 buf;

phydev = phy_find_first(dev->mdiobus);
if (!phydev) {
netdev_dbg(dev->net, "PHY Not Found!! Forcing RGMII configuration\n");
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;
}

@@ -2668,7 +2677,7 @@ 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_GMII;
@@ -2676,7 +2685,7 @@ 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 */
@@ -2690,10 +2699,15 @@ 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);

@@ -2706,7 +2720,10 @@ 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_ |
@@ -2715,7 +2732,9 @@ 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