Message ID | 20200619044759.11387-3-f.fainelli@gmail.com |
---|---|
State | New |
Headers | show |
Series | None | expand |
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index 04946de74fa0..85ba95b598b5 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -794,8 +794,10 @@ static int get_phy_id(struct mii_bus *bus, int addr, u32 *phy_id, /* Grab the bits from PHYIR2, and put them in the lower half */ phy_reg = mdiobus_read(bus, addr, MII_PHYSID2); - if (phy_reg < 0) - return -EIO; + if (phy_reg < 0) { + /* returning -ENODEV doesn't stop bus scanning */ + return (phy_reg == -EIO || phy_reg == -ENODEV) ? -ENODEV : -EIO; + } *phy_id |= phy_reg;
Commit 02a6efcab675 ("net: phy: allow scanning busses with missing phys") added a special condition to return -ENODEV in case -ENODEV or -EIO was returned from the first read of the MII_PHYSID1 register. In case the MDIO bus data line pull-up is not strong enough, the MDIO bus controller will not flag this as a read error. This can happen when a pluggable daughter card is not connected and weak internal pull-ups are used (since that is the only option, otherwise the pins are floating). The second read of MII_PHYSID2 will be correctly flagged an error though, but now we will return -EIO which will be treated as a hard error, thus preventing MDIO bus scanning loops to continue succesfully. Apply the same logic to both register reads, thus allowing the scanning logic to proceed. Fixes: 02a6efcab675 ("net: phy: allow scanning busses with missing phys") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> --- drivers/net/phy/phy_device.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)