Re: [net-next PATCH v3 5/5] net: mdiobus: Introduce fwnode_mdiobus_register_phy()

Andy Shevchenko
2020-05-05T14:22:11Z

On Tue, May 5, 2020 at 4:30 PM Calvin Johnson
<calvin.johnson@oss.nxp.com> wrote:
>
> Introduce fwnode_mdiobus_register_phy() to register PHYs on the
> mdiobus. From the compatible string, identify whether the PHY is
> c45 and based on this create a PHY device instance which is
> registered on the mdiobus.

...

> +int fwnode_mdiobus_register_phy(struct mii_bus *bus,
> + struct fwnode_handle *child, u32 addr)
> +{
> + struct phy_device *phy;

> + bool is_c45 = false;

Redundant assignment, see below.

> + const char *cp;
> + u32 phy_id;
> + int rc;
> +

> + fwnode_property_read_string(child, "compatible", &cp);

Consider rc = ...; otherwise you will have UB below.

> + if (!strcmp(cp, "ethernet-phy-ieee802.3-c45"))

UB!

> + is_c45 = true;

is_c45 = !(rc || strcmp(...));

> + if (!is_c45 && !fwnode_get_phy_id(child, &phy_id))

Perhaps positive conditional

if (is_c45 || fwnode_...(...))
get_phy_device();
else
...

> + phy = phy_device_create(bus, addr, phy_id, 0, NULL);
> + else
> + phy = get_phy_device(bus, addr, is_c45);
> + if (IS_ERR(phy))
> + return PTR_ERR(phy);
> +
> + phy->irq = bus->irq[addr];
> +
> + /* Associate the fwnode with the device structure so it
> + * can be looked up later.
> + */
> + phy->mdio.dev.fwnode = child;
> +
> + /* All data is now stored in the phy struct, so register it */
> + rc = phy_device_register(phy);
> + if (rc) {
> + phy_device_free(phy);

> + fwnode_handle_put(child);

Shouldn't mdio.dev.fwnode be put rather than child (yes, I see the assignment)

> + return rc;
> + }
> +
> + dev_dbg(&bus->dev, "registered phy at address %i\n", addr);
> +
> + return 0;
> +}

--
With Best Regards,
Andy Shevchenko