[SOLVED] LXT973 support (dual PHY with single MDIO)

[Vitaly Bordug]

On Tue, 30 May 2006 11:28:48 +0200
Laurent Pinchart <laurent.pinchart at tbox.biz> wrote:

> Hi,
> 
> once again, posting to a mailing list helped me solving my problem. It should 
> have been obvious that the MDIO bus is really a bus, and can as such support 
> several devices. The issue was that the drivers/net/fs_enet driver set 
> bus->phy_mask to ~0x9, and the LXT973 uses addresses 0 and 1. Address 1 thus 
> never got probed. What's the reason for probing addresses 0 and 3 only ?

The reason is obvious: bitbang read of PHY id with not-existent PHY, does not return expected (0, iirc), that confuse mdio bus device-driver bound (it assumes error and returns -1), and prevents from probing other phys. So, as that seems to be a "feature" on CPM2 only, we are working that around specifying phy_mask to prevent probing inexistent phys w/over bitbang thing.


-- 
Sincerely, 
Vitaly