Re: [PATCH] net: phy: turn carrier off on phy attach

From: Sjoerd Simons
Date: Thu Jan 14 2016 - 15:23:07 EST


On Tue, 2016-01-12 at 17:31 -0800, Florian Fainelli wrote:
> On January 9, 2016 10:44:05 AM PST, Sjoerd Simons <sjoerd.simons@coll
> abora.co.uk> wrote:
> > The operstate of a networking device initially IF_OPER_UNKNOWN aka
> > "unknown", updated on carrier state changes (with carrier state
> > being
> > on
> > by default). This means it will stay unknown unless the carrier
> > state
> > goes to off at some point, which is not the case if the phy is
> > already
> > up/connected at startup.
>
> Correct, drivers typically call netif_carrier_off prior to
> registering the network device to give a predictable link state,
> regardless of whether or not they use PHYLIB.
>
> >
> > Explicitly turn off the carrier on phy attach, leaving the phy
> > state
> > machine to turn the carrier on when it has done the initial
> > negotiation.
>
> Same comment as Andrew on the comment below.
>
> Out of curiosity, was there a particular driver you ran into issues
> with?

Prepping a v2. This came up on Rada Rock2 board, so the (Rockchip)
DWMAC driver combined with a realtek phy (RTL8211E). Thanks for the
review

--
Sjoerd Simons
Collabora Ltd.