[RFC PATCH net-next] net: phy: force phy suspend when calling phy_stop

[RFC PATCH net-next] net: phy: force phy suspend when calling phy_stop

[Jian Shen]

Some ethernet drivers may call phy_start() and phy_stop() from
ndo_open and ndo_close() respectively.

When network cable is unconnected, and operate like below:
step 1: ifconfig ethX up -> ndo_open -> phy_start ->start
autoneg, and phy is no link.
step 2: ifconfig ethX down -> ndo_close -> phy_stop -> just stop
phy state machine.
step 3: plugin the network cable, and autoneg complete, then
LED for link status will be on.
step 4: ethtool ethX --> see the result of "Link detected" is no.

This patch forces phy suspend even phydev->link is off.

Signed-off-by: Jian Shen <shenjian15@huawei.com>
---
 drivers/net/phy/phy.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index f3adea9..0acd5b4 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -911,8 +911,8 @@ void phy_state_machine(struct work_struct *work)
 		if (phydev->link) {
 			phydev->link = 0;
 			phy_link_down(phydev, true);
-			do_suspend = true;
 		}
+		do_suspend = true;
 		break;
 	}
 
-- 
2.8.1

Re: [RFC PATCH net-next] net: phy: force phy suspend when calling phy_stop

[Heiner Kallweit]

On 27.08.2019 04:47, Jian Shen wrote:
> Some ethernet drivers may call phy_start() and phy_stop() from
> ndo_open and ndo_close() respectively.
> 
> When network cable is unconnected, and operate like below:
> step 1: ifconfig ethX up -> ndo_open -> phy_start ->start
> autoneg, and phy is no link.
> step 2: ifconfig ethX down -> ndo_close -> phy_stop -> just stop
> phy state machine.
> step 3: plugin the network cable, and autoneg complete, then
> LED for link status will be on.
> step 4: ethtool ethX --> see the result of "Link detected" is no.
> 
Step 3 and 4 seem to be unrelated to the actual issue.
With which MAC + PHY driver did you observe this?

> This patch forces phy suspend even phydev->link is off.
> 
> Signed-off-by: Jian Shen <shenjian15@huawei.com>
> ---
>  drivers/net/phy/phy.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
> index f3adea9..0acd5b4 100644
> --- a/drivers/net/phy/phy.c
> +++ b/drivers/net/phy/phy.c
> @@ -911,8 +911,8 @@ void phy_state_machine(struct work_struct *work)
>  		if (phydev->link) {
>  			phydev->link = 0;
>  			phy_link_down(phydev, true);
> -			do_suspend = true;
>  		}
> +		do_suspend = true;
>  		break;
>  	}
>  
> 
Heiner

Re: [RFC PATCH net-next] net: phy: force phy suspend when calling phy_stop

[shenjian (K)]

在 2019/8/27 13:51, Heiner Kallweit 写道:
> On 27.08.2019 04:47, Jian Shen wrote:
>> Some ethernet drivers may call phy_start() and phy_stop() from
>> ndo_open and ndo_close() respectively.
>>
>> When network cable is unconnected, and operate like below:
>> step 1: ifconfig ethX up -> ndo_open -> phy_start ->start
>> autoneg, and phy is no link.
>> step 2: ifconfig ethX down -> ndo_close -> phy_stop -> just stop
>> phy state machine.
>> step 3: plugin the network cable, and autoneg complete, then
>> LED for link status will be on.
>> step 4: ethtool ethX --> see the result of "Link detected" is no.
>>
> Step 3 and 4 seem to be unrelated to the actual issue.
> With which MAC + PHY driver did you observe this?
> 
Thanks Heiner,

I tested this on HNS3 driver, with two phy, Marvell 88E1512 and RTL8211.

Step 3 and Step 4 is just to describe that the LED of link shows link up,
but the port information shows no link.


>> This patch forces phy suspend even phydev->link is off.
>>
>> Signed-off-by: Jian Shen <shenjian15@huawei.com>
>> ---
>>  drivers/net/phy/phy.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
>> index f3adea9..0acd5b4 100644
>> --- a/drivers/net/phy/phy.c
>> +++ b/drivers/net/phy/phy.c
>> @@ -911,8 +911,8 @@ void phy_state_machine(struct work_struct *work)
>>  		if (phydev->link) {
>>  			phydev->link = 0;
>>  			phy_link_down(phydev, true);
>> -			do_suspend = true;
>>  		}
>> +		do_suspend = true;
>>  		break;
>>  	}
>>  
>>
> Heiner
> 
> 

Re: [RFC PATCH net-next] net: phy: force phy suspend when calling phy_stop

[Heiner Kallweit]

On 27.08.2019 10:29, shenjian (K) wrote:
> 
> 
> 在 2019/8/27 13:51, Heiner Kallweit 写道:
>> On 27.08.2019 04:47, Jian Shen wrote:
>>> Some ethernet drivers may call phy_start() and phy_stop() from
>>> ndo_open and ndo_close() respectively.
>>>
>>> When network cable is unconnected, and operate like below:
>>> step 1: ifconfig ethX up -> ndo_open -> phy_start ->start
>>> autoneg, and phy is no link.
>>> step 2: ifconfig ethX down -> ndo_close -> phy_stop -> just stop
>>> phy state machine.
>>> step 3: plugin the network cable, and autoneg complete, then
>>> LED for link status will be on.
>>> step 4: ethtool ethX --> see the result of "Link detected" is no.
>>>
>> Step 3 and 4 seem to be unrelated to the actual issue.
>> With which MAC + PHY driver did you observe this?
>>
> Thanks Heiner,
> 
> I tested this on HNS3 driver, with two phy, Marvell 88E1512 and RTL8211.
> 
> Step 3 and Step 4 is just to describe that the LED of link shows link up,
> but the port information shows no link.
> 
ethtool refers to the link at MAC level. Therefore default implementation
ethtool_op_get_link just returns the result of netif_carrier_ok().
Also using PHY link status if interface is down doesn't really make sense:
- phylib state machine isn't running, therefore PHY status doesn't get updated
- often MAC drivers shut down parts of the MAC on ndo_close, this typically
  makes the internal MDIO bus unaccessible
So just remove steps 3 and 4. The patch itself is fine with me.

> 
>>> This patch forces phy suspend even phydev->link is off.
>>>
>>> Signed-off-by: Jian Shen <shenjian15@huawei.com>
>>> ---
>>>  drivers/net/phy/phy.c | 2 +-
>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
>>> index f3adea9..0acd5b4 100644
>>> --- a/drivers/net/phy/phy.c
>>> +++ b/drivers/net/phy/phy.c
>>> @@ -911,8 +911,8 @@ void phy_state_machine(struct work_struct *work)
>>>  		if (phydev->link) {
>>>  			phydev->link = 0;
>>>  			phy_link_down(phydev, true);
>>> -			do_suspend = true;
>>>  		}
>>> +		do_suspend = true;
>>>  		break;
>>>  	}
>>>  
>>>
>> Heiner
>>
>>
> 
> 

Re: [RFC PATCH net-next] net: phy: force phy suspend when calling phy_stop

[shenjian (K)]

在 2019/8/28 3:41, Heiner Kallweit 写道:
> On 27.08.2019 10:29, shenjian (K) wrote:
>>
>>
>> 在 2019/8/27 13:51, Heiner Kallweit 写道:
>>> On 27.08.2019 04:47, Jian Shen wrote:
>>>> Some ethernet drivers may call phy_start() and phy_stop() from
>>>> ndo_open and ndo_close() respectively.
>>>>
>>>> When network cable is unconnected, and operate like below:
>>>> step 1: ifconfig ethX up -> ndo_open -> phy_start ->start
>>>> autoneg, and phy is no link.
>>>> step 2: ifconfig ethX down -> ndo_close -> phy_stop -> just stop
>>>> phy state machine.
>>>> step 3: plugin the network cable, and autoneg complete, then
>>>> LED for link status will be on.
>>>> step 4: ethtool ethX --> see the result of "Link detected" is no.
>>>>
>>> Step 3 and 4 seem to be unrelated to the actual issue.
>>> With which MAC + PHY driver did you observe this?
>>>
>> Thanks Heiner,
>>
>> I tested this on HNS3 driver, with two phy, Marvell 88E1512 and RTL8211.
>>
>> Step 3 and Step 4 is just to describe that the LED of link shows link up,
>> but the port information shows no link.
>>
> ethtool refers to the link at MAC level. Therefore default implementation
> ethtool_op_get_link just returns the result of netif_carrier_ok().
> Also using PHY link status if interface is down doesn't really make sense:
> - phylib state machine isn't running, therefore PHY status doesn't get updated
> - often MAC drivers shut down parts of the MAC on ndo_close, this typically
>   makes the internal MDIO bus unaccessible
> So just remove steps 3 and 4. The patch itself is fine with me.
> 
OK, I will fix the commit log.
Thanks, Heiner.
>>
>>>> This patch forces phy suspend even phydev->link is off.
>>>>
>>>> Signed-off-by: Jian Shen <shenjian15@huawei.com>
>>>> ---
>>>>  drivers/net/phy/phy.c | 2 +-
>>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
>>>> index f3adea9..0acd5b4 100644
>>>> --- a/drivers/net/phy/phy.c
>>>> +++ b/drivers/net/phy/phy.c
>>>> @@ -911,8 +911,8 @@ void phy_state_machine(struct work_struct *work)
>>>>  		if (phydev->link) {
>>>>  			phydev->link = 0;
>>>>  			phy_link_down(phydev, true);
>>>> -			do_suspend = true;
>>>>  		}
>>>> +		do_suspend = true;
>>>>  		break;
>>>>  	}
>>>>  
>>>>
>>> Heiner
>>>
>>>
>>
>>
> 
> 
> .
> 

Re: [RFC PATCH net-next] net: phy: force phy suspend when calling phy_stop

[Sergei Shtylyov]

On 27.08.2019 5:47, Jian Shen wrote:

> Some ethernet drivers may call phy_start() and phy_stop() from
> ndo_open and ndo_close() respectively.

    ndo_open() for consistency.

> When network cable is unconnected, and operate like below:
> step 1: ifconfig ethX up -> ndo_open -> phy_start ->start
> autoneg, and phy is no link.
> step 2: ifconfig ethX down -> ndo_close -> phy_stop -> just stop
> phy state machine.
> step 3: plugin the network cable, and autoneg complete, then
> LED for link status will be on.
> step 4: ethtool ethX --> see the result of "Link detected" is no.
> 
> This patch forces phy suspend even phydev->link is off.
> 
> Signed-off-by: Jian Shen <shenjian15@huawei.com>
[...]

MBR, Sergei

Re: [RFC PATCH net-next] net: phy: force phy suspend when calling phy_stop

[shenjian (K)]

在 2019/8/27 18:11, Sergei Shtylyov 写道:
> On 27.08.2019 5:47, Jian Shen wrote:
> 
>> Some ethernet drivers may call phy_start() and phy_stop() from
>> ndo_open and ndo_close() respectively.
> 
>    ndo_open() for consistency.
> 
>> When network cable is unconnected, and operate like below:
>> step 1: ifconfig ethX up -> ndo_open -> phy_start ->start
>> autoneg, and phy is no link.
>> step 2: ifconfig ethX down -> ndo_close -> phy_stop -> just stop
>> phy state machine.
>> step 3: plugin the network cable, and autoneg complete, then
>> LED for link status will be on.
>> step 4: ethtool ethX --> see the result of "Link detected" is no.
>>
>> This patch forces phy suspend even phydev->link is off.
>>
>> Signed-off-by: Jian Shen <shenjian15@huawei.com>
> [...]
> 
> MBR, Sergei
> 
> 
Thanks, will fix it.