Re: [PATCH v1 net] net: stmmac: removed enabling eee in EEE set callback

[mark gross]

Acked-by: Mark Gross <mgross@xxxxxxxxxxxxxxx>

On Wed, Sep 23, 2020 at 04:56:14PM +0800, Voon Weifeng wrote:
> EEE should be only be enabled during stmmac_mac_link_up() when the
> link are up and being set up properly. set_eee should only do settings
> configuration and disabling the eee.
> 
> Without this fix, turning on EEE using ethtool will return
> "Operation not supported". This is due to the driver is in a dead loop
> waiting for eee to be advertised in the for eee to be activated but the
> driver will only configure the EEE advertisement after the eee is
> activated.
> 
> Ethtool should only return "Operation not supported" if there is no EEE
> capbility in the MAC controller.
> 
> Fixes: 8a7493e58ad6 ("net: stmmac: Fix a race in EEE enable callback")
> 
> Signed-off-by: Voon Weifeng <weifeng.voon@xxxxxxxxx>
> ---
>  .../net/ethernet/stmicro/stmmac/stmmac_ethtool.c  | 15 ++++-----------
>  1 file changed, 4 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
> index ac5e8cc5fb9f..430a4b32ec1e 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
> @@ -675,23 +675,16 @@ static int stmmac_ethtool_op_set_eee(struct net_device *dev,
>  	struct stmmac_priv *priv = netdev_priv(dev);
>  	int ret;
>  
> -	if (!edata->eee_enabled) {
> +	if (!priv->dma_cap.eee)
> +		return -EOPNOTSUPP;
> +
> +	if (!edata->eee_enabled)
>  		stmmac_disable_eee_mode(priv);
> -	} else {
> -		/* We are asking for enabling the EEE but it is safe
> -		 * to verify all by invoking the eee_init function.
> -		 * In case of failure it will return an error.
> -		 */
> -		edata->eee_enabled = stmmac_eee_init(priv);
> -		if (!edata->eee_enabled)
> -			return -EOPNOTSUPP;
> -	}
>  
>  	ret = phylink_ethtool_set_eee(priv->phylink, edata);
>  	if (ret)
>  		return ret;
>  
> -	priv->eee_enabled = edata->eee_enabled;
>  	priv->tx_lpi_timer = edata->tx_lpi_timer;
>  	return 0;
>  }
> -- 
> 2.17.1
>