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Subject: Re: [PATCH] net: phy: micrel: reconfigure the phy on resume
To:     Claudiu Beznea <claudiu.beznea@microchip.com>, andrew@lunn.ch,
        linux@armlinux.org.uk, davem@davemloft.net, kuba@kernel.org
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org
References: <1610120754-14331-1-git-send-email-claudiu.beznea@microchip.com>
From:   Heiner Kallweit <hkallweit1@gmail.com>
Message-ID: <25ec943f-ddfc-9bcd-ef30-d0baf3c6b2a2@gmail.com>
Date:   Fri, 8 Jan 2021 17:31:48 +0100
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On 08.01.2021 16:45, Claudiu Beznea wrote:
> KSZ9131 is used in setups with SAMA7G5. SAMA7G5 supports a special
> power saving mode (backup mode) that cuts the power for almost all
> parts of the SoC. The rail powering the ethernet PHY is also cut off.
> When resuming, in case the PHY has been configured on probe with
> slew rate or DLL settings these needs to be restored thus call
> driver's config_init() on resume.
> 
When would the SoC enter this backup mode? And would it suspend the
MDIO bus before cutting power to the PHY?
I'm asking because in mdio_bus_phy_restore() we call phy_init_hw()
already (that calls the driver's config_init).

> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
> ---
>  drivers/net/phy/micrel.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
> index 3fe552675dd2..52d3a0480158 100644
> --- a/drivers/net/phy/micrel.c
> +++ b/drivers/net/phy/micrel.c
> @@ -1077,7 +1077,7 @@ static int kszphy_resume(struct phy_device *phydev)
>  	 */
>  	usleep_range(1000, 2000);
>  
> -	ret = kszphy_config_reset(phydev);
> +	ret = phydev->drv->config_init(phydev);
>  	if (ret)
>  		return ret;
>  
>