On Mon, Mar 30, 2020 at 07:01:36PM +0300, Codrin Ciubotariu wrote:
> Some ethernet controllers, such as cadence's macb, have an embedded MDIO.
> For this reason, the ethernet PHY nodes are not under an MDIO bus, but
> directly under the ethernet node. Since these drivers might use
> of_mdiobus_child_is_phy(), we should fix this function by returning false
> if a fixed-link is found.
So i assume the problem occurs here:
static int macb_mdiobus_register(struct macb *bp)
{
struct device_node *child, *np = bp->pdev->dev.of_node;
/* Only create the PHY from the device tree if at least one PHY is
* described. Otherwise scan the entire MDIO bus. We do this to support
* old device tree that did not follow the best practices and did not
* describe their network PHYs.
*/
for_each_available_child_of_node(np, child)
if (of_mdiobus_child_is_phy(child)) {
/* The loop increments the child refcount,
* decrement it before returning.
*/
of_node_put(child);
return of_mdiobus_register(bp->mii_bus, np);
}
return mdiobus_register(bp->mii_bus);
}
I think a better solution is
for_each_available_child_of_node(np, child)
+ if (of_phy_is_fixed_link(child)
+ continue;
if (of_mdiobus_child_is_phy(child)) {
/* The loop increments the child refcount,
* decrement it before returning.
*/
of_node_put(child);
return of_mdiobus_register(bp->mii_bus, np);
}
return mdiobus_register(bp->mii_bus);
}
This problem is only an issue for macb, so keep the fix local to macb.
Andrew
