Re: [net-next PATCH v2 02/14] net: phy: Introduce phy related fwnode functions

[Andy Shevchenko <andy.shevchenko@gmail.com>]

On Tue, Dec 15, 2020 at 6:44 PM Calvin Johnson
<calvin.johnson@oss.nxp.com> wrote:
>
> Define fwnode_phy_find_device() to iterate an mdiobus and find the
> phy device of the provided phy fwnode. Additionally define
> device_phy_find_device() to find phy device of provided device.
>
> Define fwnode_get_phy_node() to get phy_node using named reference.

...

> +#include <linux/acpi.h>

Not sure we need this. See below.

...

> +/**
> + * fwnode_phy_find_device - Find phy_device on the mdiobus for the provided
> + * phy_fwnode.

Can we keep a summary on one line?

> + * @phy_fwnode: Pointer to the phy's fwnode.
> + *
> + * If successful, returns a pointer to the phy_device with the embedded
> + * struct device refcount incremented by one, or NULL on failure.
> + */
> +struct phy_device *fwnode_phy_find_device(struct fwnode_handle *phy_fwnode)
> +{
> +       struct mdio_device *mdiodev;
> +       struct device *d;

> +       if (!phy_fwnode)
> +               return NULL;

Why is this needed?
Perhaps a comment to the function description explains a case when
@phy_fwnode == NULL.

> +       d = bus_find_device_by_fwnode(&mdio_bus_type, phy_fwnode);
> +       if (d) {
> +               mdiodev = to_mdio_device(d);
> +               if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY)
> +                       return to_phy_device(d);
> +               put_device(d);
> +       }
> +
> +       return NULL;
> +}

...

> + * For ACPI, only "phy-handle" is supported. DT supports all the three
> + * named references to the phy node.

...

> +       /* Only phy-handle is used for ACPI */
> +       phy_node = fwnode_find_reference(fwnode, "phy-handle", 0);
> +       if (is_acpi_node(fwnode) || !IS_ERR(phy_node))
> +               return phy_node;

So, what is the problem with going through the rest on ACPI?
Usually we describe the restrictions in the documentation.

-- 
With Best Regards,
Andy Shevchenko