From 17b447539408a0feff81637c7cc1c4c68efa73c0 Mon Sep 17 00:00:00 2001 From: Andrew Lunn Date: Sun, 4 Feb 2024 17:14:14 -0600 Subject: [PATCH 1/2] net: phy: c45 scanning: Don't consider -ENODEV fatal When scanning the MDIO bus for C22 devices, the driver returning -ENODEV is not considered fatal, it just indicates the MDIO bus master knows there is no device at that address, maybe because of hardware limitation. Make the C45 scan code act on -ENODEV the same way, to make C22 and C45 more uniform. It is expected all reads for a given address will return -ENODEV, so within get_phy_c45_ids() only the first place a read occurs has been changed. Reviewed-by: Florian Fainelli Signed-off-by: Andrew Lunn Signed-off-by: David S. Miller --- drivers/net/phy/phy_device.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index 839e42f9e16a..2e7d5bfb338e 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -780,7 +780,7 @@ static int get_phy_c45_devs_in_pkg(struct mii_bus *bus, int addr, int dev_addr, * and identifiers in @c45_ids. * * Returns zero on success, %-EIO on bus access error, or %-ENODEV if - * the "devices in package" is invalid. + * the "devices in package" is invalid or no device responds. */ static int get_phy_c45_ids(struct mii_bus *bus, int addr, struct phy_c45_device_ids *c45_ids) @@ -803,7 +803,11 @@ static int get_phy_c45_ids(struct mii_bus *bus, int addr, */ ret = phy_c45_probe_present(bus, addr, i); if (ret < 0) - return -EIO; + /* returning -ENODEV doesn't stop bus + * scanning + */ + return (phy_reg == -EIO || + phy_reg == -ENODEV) ? -ENODEV : -EIO; if (!ret) continue; From 88b3934e3f31e15b40896aa8ebb0a8040d150c1c Mon Sep 17 00:00:00 2001 From: Andrew Lunn Date: Sun, 4 Feb 2024 17:14:15 -0600 Subject: [PATCH 2/2] net: dsa: mv88e6xxx: Return -ENODEV when C45 not supported MDIO bus drivers can return -ENODEV when they know the bus does not have a device at the given address, e.g. because of hardware limitation. One such limitation is that the bus does not support C45 at all. This is more efficient than returning 0xffff, since it immediately stops the probing on the given address, where as further reads can be made when 0xffff is returned. Signed-off-by: Andrew Lunn Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- drivers/net/dsa/mv88e6xxx/chip.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c index 6eec2e4aa031..9caecb4dfbfa 100644 --- a/drivers/net/dsa/mv88e6xxx/chip.c +++ b/drivers/net/dsa/mv88e6xxx/chip.c @@ -3659,7 +3659,7 @@ static int mv88e6xxx_mdio_read_c45(struct mii_bus *bus, int phy, int devad, int err; if (!chip->info->ops->phy_read_c45) - return 0xffff; + return -ENODEV; mv88e6xxx_reg_lock(chip); err = chip->info->ops->phy_read_c45(chip, bus, phy, devad, reg, &val);