| Message ID | 1462150051-6308-1-git-send-email-marex@denx.de |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Marek Vasut <marex@denx.de> Date: Mon, 2 May 2016 02:47:31 +0200 > Since commit b74766a0a0fe ("phylib: don't return NULL > from get_phy_device()") in linux-next, phy_get_device() will return > ERR_PTR(-ENODEV) instead of NULL if the PHY device ID is all ones. > > This causes problem with stmmac driver and likely some other drivers > which call mdiobus_register(). I triggered this bug on SoCFPGA MCVEVK > board with linux-next 20160427 and 20160428. In case of the stmmac, if > there is no PHY node specified in the DT for the stmmac block, the stmmac > driver ( drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c function > stmmac_mdio_register() ) will call mdiobus_register() , which will > register the MDIO bus and probe for the PHY. > > The mdiobus_register() resp. __mdiobus_register() iterates over all of > the addresses on the MDIO bus and calls mdiobus_scan() for each of them, > which invokes get_phy_device(). Before the aforementioned patch, the > mdiobus_scan() would return NULL if no PHY was found on a given address > and mdiobus_register() would continue and try the next PHY address. Now, > mdiobus_scan() returns ERR_PTR(-ENODEV), which is caught by the > 'if (IS_ERR(phydev))' condition and the loop exits immediately if the > PHY address does not contain PHY. > > Repair this by explicitly checking for the ERR_PTR(-ENODEV) and if this > error comes around, continue with the next PHY address. > > Signed-off-by: Marek Vasut <marex@denx.de> > Acked-by: Florian Fainelli <f.fainelli@gmail.com> Applied, thanks.
diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c index 499003ee..388f992 100644 --- a/drivers/net/phy/mdio_bus.c +++ b/drivers/net/phy/mdio_bus.c @@ -333,7 +333,7 @@ int __mdiobus_register(struct mii_bus *bus, struct module *owner) struct phy_device *phydev; phydev = mdiobus_scan(bus, i); - if (IS_ERR(phydev)) { + if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV)) { err = PTR_ERR(phydev); goto error; }
Since commit b74766a0a0fe ("phylib: don't return NULL from get_phy_device()") in linux-next, phy_get_device() will return ERR_PTR(-ENODEV) instead of NULL if the PHY device ID is all ones. This causes problem with stmmac driver and likely some other drivers which call mdiobus_register(). I triggered this bug on SoCFPGA MCVEVK board with linux-next 20160427 and 20160428. In case of the stmmac, if there is no PHY node specified in the DT for the stmmac block, the stmmac driver ( drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c function stmmac_mdio_register() ) will call mdiobus_register() , which will register the MDIO bus and probe for the PHY. The mdiobus_register() resp. __mdiobus_register() iterates over all of the addresses on the MDIO bus and calls mdiobus_scan() for each of them, which invokes get_phy_device(). Before the aforementioned patch, the mdiobus_scan() would return NULL if no PHY was found on a given address and mdiobus_register() would continue and try the next PHY address. Now, mdiobus_scan() returns ERR_PTR(-ENODEV), which is caught by the 'if (IS_ERR(phydev))' condition and the loop exits immediately if the PHY address does not contain PHY. Repair this by explicitly checking for the ERR_PTR(-ENODEV) and if this error comes around, continue with the next PHY address. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David S. Miller <davem@davemloft.net> Cc: Dinh Nguyen <dinguyen@opensource.altera.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> --- V2: Fixed checkpatch warning in the commit message Added Ack from Florian --- drivers/net/phy/mdio_bus.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)