Re: [PATCH] net: davinci_mdio: add GPIO reset logic

From: David Miller
Date: Sat Apr 08 2017 - 09:59:29 EST


From: Roger Quadros <rogerq@xxxxxx>
Date: Wed, 5 Apr 2017 11:33:57 +0300

> Some boards [1] leave the PHYs at an invalid state
> during system power-up or reset thus causing unreliability
> issues with the PHY like not being detected by the mdio bus
> or link not functional. To work around these boards have
> a GPIO connected to the PHY's reset pin.
>
> Implement GPIO reset handling for such cases.
>
> [1] - am572x-idk, am571x-idk, a437x-idk.
>
> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
> Signed-off-by: Sekhar Nori <nsekhar@xxxxxx>

I have not seen a resolution in this discussion.

My understanding is that there are several cases (single MDIO bus whose
reset does a reset on all that MDIO bus's PHYs, etc.) and it's unclear
how to handle all such cases cleanly.