Re: [PATCH net-next 2/2] net: phy: improve phy_set_sym_pause and phy_set_asym_pause

[Heiner Kallweit <hkallweit1@gmail.com>]

On 29.04.2019 23:52, Andrew Lunn wrote:
>> @@ -2078,6 +2089,11 @@ EXPORT_SYMBOL(phy_set_sym_pause);
>>  void phy_set_asym_pause(struct phy_device *phydev, bool rx, bool tx)
>>  {
>>  	__ETHTOOL_DECLARE_LINK_MODE_MASK(oldadv);
>> +	bool asym_pause_supported;
>> +
>> +	asym_pause_supported =
>> +		linkmode_test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
>> +				  phydev->supported);
>>  
>>  	linkmode_copy(oldadv, phydev->advertising);
>>  
>> @@ -2086,14 +2102,14 @@ void phy_set_asym_pause(struct phy_device *phydev, bool rx, bool tx)
>>  	linkmode_clear_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
>>  			   phydev->advertising);
>>  
>> -	if (rx) {
>> +	if (rx && asym_pause_supported) {
>>  		linkmode_set_bit(ETHTOOL_LINK_MODE_Pause_BIT,
>>  				 phydev->advertising);
>>  		linkmode_set_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
>>  				 phydev->advertising);
>>  	}
>>  
>> -	if (tx)
>> +	if (tx && asym_pause_supported)
>>  		linkmode_change_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
>>  				    phydev->advertising);
> 
> Hi Heiner
> 
Hi Andrew,

> If the PHY only supports Pause, not Asym Pause, i wounder if we should
> fall back to Pause here?
> 
I wasn't sure about whether a silent fallback is the expected behavior.
Also open is whether we can rely on a set_pause callback having called
phy_validate_pause() before. Another option could be to change the
return type to int and return an error like -EOPNOTSUPP if the requested
mode isn't supported.

>      Andrew
> 
Heiner