Re: [PATCH 1/1] Workaround for Suspend/Resume issue of AX88772B under ChromeOS

[Florian Fainelli]

2013/11/21 Grant Grundler <grundler@xxxxxxxxxx>:
> On Wed, Nov 20, 2013 at 11:32 AM, Grant Grundler <grundler@xxxxxxxxxx> wrote:
>> Seems like this should be part of usbnet_resume code based on whether
>> the driver provides mdio_write hook (most USBNET drivers do).
>
> Just to be clear: I don't think this is feasible for the now obvious
> reason that not all device lose phy stat on resume. :/
>
> Freddy sent me a patch that saves/restores MII_ADVERTISE and MII_BMCR
> registers. Testing that now and he'll post if that all works out.

That should be enough to ensure the PHY is put back into a consistent
state. So long as you are suspending/resuming from a configuration
where autoneg was enabled, I would not expect anything bad to happen.
If the link was forced, that is a different story.

One way to make sure this work properly without driver-specific code
is to include that functionality into the PHY library. As far as I can
see it the asix drivers do not use it but implement the old-style
mii_bus interface so that would be a first step.
-- 
Florian
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