Subject: Re: [PATCH v3 1/3] netdev/of/phy: New function: of_mdio_find_bus().

From: David Daney <[email-masked]>
Date: Tue, 17 Apr 2012 10:27:43 -0700

On 04/16/2012 06:03 PM, David Daney wrote:
> From: David Daney<[email-masked]>
>
> Add of_mdio_find_bus() which allows an mii_bus to be located given its
> associated the device tree node.
>
> This is needed by the follow-on patch to add a driver for MDIO bus
> multiplexers.
>
> The of_mdiobus_register() function is modified so that the device tree
> node is recorded in the mii_bus.  Then we can find it again by
> iterating over all mdio_bus_class devices.
>
> Because the OF device tree has now become an integral part of the
> kernel, this can live in mdio_bus.c (which contains the needed
> mdio_bus_class structure) instead of of_mdio.c.
>
> Signed-off-by: David Daney<[email-masked]>
> Cc: Grant Likely<[email-masked]>
> Cc: "David S. Miller"<[email-masked]>
> ---
>   drivers/net/phy/mdio_bus.c |   32 ++++++++++++++++++++++++++++++++
>   drivers/of/of_mdio.c       |    2 ++
>   include/linux/of_mdio.h    |    2 ++
>   3 files changed, 36 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
> index 8985cc6..46e7dc5 100644
> --- a/drivers/net/phy/mdio_bus.c
> +++ b/drivers/net/phy/mdio_bus.c
> @@ -88,6 +88,38 @@ static struct class mdio_bus_class = {
>   	.dev_release	= mdiobus_release,
>   };
>
> +#ifdef CONFIG_OF_MDIO
> +/* Helper function for of_phy_find_device */

This comment is incorrect.  I will resend the set with this cleaned up.

David Daney

> +static int of_mii_bus_match(struct device *dev, void *mii_bus_np)
> +{
> +	return dev->of_node == mii_bus_np;
> +}
> +/**
> + * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
> + * @mdio_np: Pointer to the mii_bus.
> + *
> + * Returns a pointer to the mii_bus, or NULL if none found.
> + *
> + * Because the association of a device_node and mii_bus is made via
> + * of_mdiobus_register(), the mii_bus cannot be found before it is
> + * registered with of_mdiobus_register().
> + *
> + */
> +struct mii_bus *of_mdio_find_bus(struct device_node *mdio_np)
> +{
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