Re: [PATCH] [v2] net: qcom/emac: add ethtool support

[Timur Tabi <timur@codeaurora.org>]

Timur Tabi wrote:
> +static void emac_get_pauseparam(struct net_device *netdev,
> +				struct ethtool_pauseparam *pause)
> +{
> +	struct phy_device *phydev = netdev->phydev;
> +
> +	if (phydev) {
> +		if (phydev->autoneg)
> +			pause->autoneg = 1;
> +		if (phydev->pause)
> +			pause->rx_pause = 1;
> +		if (phydev->pause != phydev->asym_pause)
> +			pause->tx_pause = 1;
> +	}
> +}

I finally figured out why this code was bothering me.

This function works, as long as I do NOT implement set_pauseparam. 
That's because the driver always matches the pause frame support in the 
MAC with whatever the PHY is doing.  Since the MAC and PHY are always in 
sync, I can use the PHY settings for get_pauseparam.

However, technically this is not correct.  get_pauseparam is supposed to 
return the setting of the MAC, not the PHY.  If I also implement 
set_pauseparam, which can force the MAC to ignore the PHY and 
enable/disable pause frames arbitrarily, then the above function is wrong.

Do I finally understand this correctly?

-- 
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