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

[Heiner Kallweit <hkallweit1@gmail.com>]

On 30.04.2019 07:06, Heiner Kallweit wrote:
> 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.
> 
Most drivers call phy_validate_pause() first, this seems to be the
expected pattern. Therefore I will remove patch 2. However there seems to
be an error in phy_validate_pause(), the fix I will submit separately.

>>      Andrew
>>
> Heiner
>