Re: [PATCH net-next] net: phy: dp8382x: keep WOL setting across suspends

[POPESCU Catalin]

On 07.03.24 09:30, POPESCU Catalin wrote:
> On 07.03.24 00:04, Andrew Lunn wrote:
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>>
>>
>> On Wed, Mar 06, 2024 at 06:14:46PM +0100, Catalin Popescu wrote:
>>> Unlike other ethernet PHYs from TI, PHY dp83822x has WOL enabled
>>> at reset.
>> This is rather odd behaviour. Is this stated in the datasheet?
> Yes. I've checked all TI ethernet PHYs datasheets that are supported by
> linux and they all, but dp8382x, have WOL disabled by default. Hence,
> dp83822.c is the only driver that forcefully disable WOL at init.
>>> @@ -572,11 +584,17 @@ static int dp83826_config_init(struct phy_device *phydev)
>>>                         return ret;
>>>         }
>>>
>>> +     if (dp83822->wol_enabled)
>>> +             return 0;
>>>         return dp8382x_disable_wol(phydev);
>>>    }
>>>
>>>    static int dp8382x_config_init(struct phy_device *phydev)
>>>    {
>>> +     struct dp83822_private *dp83822 = phydev->priv;
>>> +
>>> +     if (dp83822->wol_enabled)
>>> +             return 0;
>>>         return dp8382x_disable_wol(phydev);
>> Since it is rather odd behaviour, there might be some BIOSes which
>> disable WoL. So i would not rely on it being enabled by
>> default. Explicitly enable it.
> I see, I'll make the change.

It looks like the issue I'm trying to address in this patch is not 
specific to dp8382x. Right now, depending on if the PHY is reset or not 
during resume (either through mdio_device reset_gpio/reset_ctrl or 
phy_driver soft_reset callback), the WOL configuration is either the PHY 
reset value or the BIOS value. I could still make the patch but it 
doesn't really make sense to address only dp8382x.

Also, I'm a bit confused as I'm not sure if this issue is already 
addressed by userspace or not (e.g. udevd that would reapply WOL 
configuration after suspend).

If issue should be definitely addressed in the kernel instead of 
userspace, then PAL should enforce WOL configuration for any PHY by 
calling set_wol callback after soft_reset (probably, at the end of 
phy_init_hw or after phy_resume).

>>       Andrew
>>
>> ---
>> pw-bot: cr
>