[U-Boot] [PATCH] drivers/net/phy: implement fallback mechanism for negative phy adresses

[Hannes Schmelzer]

On 3/29/19 7:03 AM, Hannes Schmelzer wrote:
> Negative phy-addresses can occour if the caller function was not able to
> determine a valid phy address (from device-tree for example). In this
> case we catch this here and search for ANY phy device on the given mdio-
> bus.
>
> Signed-off-by: Hannes Schmelzer <hannes.schmelzer at br-automation.com>
>
> ---
>
>   drivers/net/phy/phy.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
> index 0c8b29d..916b525 100644
> --- a/drivers/net/phy/phy.c
> +++ b/drivers/net/phy/phy.c
> @@ -922,13 +922,14 @@ struct phy_device *phy_connect(struct mii_dev *bus, int addr,
>   #endif
>   {
>   	struct phy_device *phydev = NULL;
> +	uint mask = (addr > 0) ? (0x1 << addr) : 0xffffffff;
>   
>   #ifdef CONFIG_PHY_FIXED
>   	phydev = phy_connect_fixed(bus, dev, interface);
>   #endif
>   
>   	if (!phydev)
> -		phydev = phy_find_by_mask(bus, 1 << addr, interface);
> +		phydev = phy_find_by_mask(bus, mask, interface);
>   
>   	if (phydev)
>   		phy_connect_dev(phydev, dev);
This fallback is only useful if the board has absolutely no description
of the phy connected to some MAC.
With some drivers, like the MXC_FEC, it is possible to configure
a phy-address within the board header.

In days where DM is more and more used, i would suggest having
a meaningful device-tree which also describes the connected ethernet-phy.

cheers,
Hannes