Re: [PATCH net-next v5 6/8] net: phy: Add phy_support_eee() indicating MAC support EEE

[Florian Fainelli <f.fainelli@gmail.com>]

On 2/20/2024 10:21 PM, Oleksij Rempel wrote:
> From: Andrew Lunn <andrew@lunn.ch>
> 
> In order for EEE to operate, both the MAC and the PHY need to support
> it, similar to how pause works. 

Kinda, a number of PHYs have added support for SmartEEE or AutoGrEEEn in 
order to provide some EEE-like power savings with non-EEE capable MACs.

Oleksij  did not you have a patch series at some point that introduced a 
smarteee field in the phy_device structure to reflect that? I thought 
that had been accepted, but maybe not.

> Copy the pause concept and add the
> call phy_support_eee() which the MAC makes after connecting the PHY to
> indicate it supports EEE. phylib will then advertise EEE when auto-neg
> is performed.
> 
> Signed-off-by: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
> ---
>   drivers/net/phy/phy_device.c | 18 ++++++++++++++++++
>   include/linux/phy.h          |  3 ++-
>   2 files changed, 20 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
> index 2eefee970851..269d3c7f0849 100644
> --- a/drivers/net/phy/phy_device.c
> +++ b/drivers/net/phy/phy_device.c
> @@ -2910,6 +2910,24 @@ void phy_advertise_eee_all(struct phy_device *phydev)
>   }
>   EXPORT_SYMBOL_GPL(phy_advertise_eee_all);
>   
> +/**
> + * phy_support_eee - Enable support of EEE
> + * @phydev: target phy_device struct
> + *
> + * Description: Called by the MAC to indicate is supports Energy
> + * Efficient Ethernet. This should be called before phy_start() in
> + * order that EEE is negotiated when the link comes up as part of
> + * phy_start(). EEE is enabled by default when the hardware supports
> + * it.

That comment is a bit confusing without mentioning how the hardware 
default state wrt. EEE is being factored in, can we have some details here?
-- 
Florian