[PATCH RFC] ixp4xx_eth: Allow setting the MDIO bus name in platform data

[Florian Fainelli]

2014-03-24 13:34 GMT-07:00 Krzysztof Halasa <khc at pm.waw.pl>:
> Simon Kågström <simon.kagstrom at netinsight.net> writes:
>
>> Allows using e.g., a fixed MDIO bus with the ixp4xx_eth driver.
>> Example:
>>
>>   static struct eth_plat_info board_plat_eth_internal[] = {
>>       {
>>               .mdio_bus_id    = "fixed-0",
>>               .phy            = 31,
>>               .rxq            = 4,
>>               .txreadyq       = 21,
>>               .hwaddr         = {0x02, 0x00, 0x00, 0x00, 0x00, 0x00},
>>       }
>>   };
>
> Why do we need it? I'm not sure I know what constitutes a "fixed MDIO
> bus".

This is a software emulation MDIO bus for when your Ethernet MAC is
connected to a PHY which does not appear on the MDIO bus. This is
typically used to provide the Ethernet driver with a link that is
always seen as UP, when you cannot directly query it via MDIO/MDC.
-- 
Florian