Re: [PATCH v1 1/1] net: usb: asix: ax88772: manage PHY PM from MAC

[Marek Szyprowski]

Hi Oleksij,

On 10.06.2021 16:20, Oleksij Rempel wrote:
> Take over PHY power management, otherwise PHY framework will try to
> access ASIX MDIO bus before MAC resume was completed.
>
> Fixes: e532a096be0e ("net: usb: asix: ax88772: add phylib support")
> Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
> Reported-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
> Reported-by: Jon Hunter <jonathanh@xxxxxxxxxx>
> Suggested-by: Heiner Kallweit <hkallweit1@xxxxxxxxx>

This fixes the issues observed on my test systems. Thanks!

Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>

> ---
>   drivers/net/usb/asix_devices.c | 43 ++++++++++------------------------
>   1 file changed, 12 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c
> index 8a477171e8f5..aec97b021a73 100644
> --- a/drivers/net/usb/asix_devices.c
> +++ b/drivers/net/usb/asix_devices.c
> @@ -598,6 +598,9 @@ static void ax88772_suspend(struct usbnet *dev)
>   	struct asix_common_private *priv = dev->driver_priv;
>   	u16 medium;
>   
> +	if (netif_running(dev->net))
> +		phy_stop(priv->phydev);
> +
>   	/* Stop MAC operation */
>   	medium = asix_read_medium_status(dev, 1);
>   	medium &= ~AX_MEDIUM_RE;
> @@ -605,14 +608,6 @@ static void ax88772_suspend(struct usbnet *dev)
>   
>   	netdev_dbg(dev->net, "ax88772_suspend: medium=0x%04x\n",
>   		   asix_read_medium_status(dev, 1));
> -
> -	/* Preserve BMCR for restoring */
> -	priv->presvd_phy_bmcr =
> -		asix_mdio_read_nopm(dev->net, dev->mii.phy_id, MII_BMCR);
> -
> -	/* Preserve ANAR for restoring */
> -	priv->presvd_phy_advertise =
> -		asix_mdio_read_nopm(dev->net, dev->mii.phy_id, MII_ADVERTISE);
>   }
>   
>   static int asix_suspend(struct usb_interface *intf, pm_message_t message)
> @@ -626,39 +621,22 @@ static int asix_suspend(struct usb_interface *intf, pm_message_t message)
>   	return usbnet_suspend(intf, message);
>   }
>   
> -static void ax88772_restore_phy(struct usbnet *dev)
> -{
> -	struct asix_common_private *priv = dev->driver_priv;
> -
> -	if (priv->presvd_phy_advertise) {
> -		/* Restore Advertisement control reg */
> -		asix_mdio_write_nopm(dev->net, dev->mii.phy_id, MII_ADVERTISE,
> -				     priv->presvd_phy_advertise);
> -
> -		/* Restore BMCR */
> -		if (priv->presvd_phy_bmcr & BMCR_ANENABLE)
> -			priv->presvd_phy_bmcr |= BMCR_ANRESTART;
> -
> -		asix_mdio_write_nopm(dev->net, dev->mii.phy_id, MII_BMCR,
> -				     priv->presvd_phy_bmcr);
> -
> -		priv->presvd_phy_advertise = 0;
> -		priv->presvd_phy_bmcr = 0;
> -	}
> -}
> -
>   static void ax88772_resume(struct usbnet *dev)
>   {
> +	struct asix_common_private *priv = dev->driver_priv;
>   	int i;
>   
>   	for (i = 0; i < 3; i++)
>   		if (!ax88772_hw_reset(dev, 1))
>   			break;
> -	ax88772_restore_phy(dev);
> +
> +	if (netif_running(dev->net))
> +		phy_start(priv->phydev);
>   }
>   
>   static void ax88772a_resume(struct usbnet *dev)
>   {
> +	struct asix_common_private *priv = dev->driver_priv;
>   	int i;
>   
>   	for (i = 0; i < 3; i++) {
> @@ -666,7 +644,8 @@ static void ax88772a_resume(struct usbnet *dev)
>   			break;
>   	}
>   
> -	ax88772_restore_phy(dev);
> +	if (netif_running(dev->net))
> +		phy_start(priv->phydev);
>   }
>   
>   static int asix_resume(struct usb_interface *intf)
> @@ -722,6 +701,8 @@ static int ax88772_init_phy(struct usbnet *dev)
>   		return ret;
>   	}
>   
> +	priv->phydev->mac_managed_pm = 1;
> +
>   	phy_attached_info(priv->phydev);
>   
>   	return 0;

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland