Re: [PATCH v3 1/2] net: phy: Fix PHY AN done state machine for interrupt driven PHYs

From: Roger Quadros
Date: Fri Mar 31 2017 - 05:20:14 EST


Florian,

On 30/03/17 23:02, Florian Fainelli wrote:
> On 03/27/2017 04:59 AM, Roger Quadros wrote:
>> The Ethernet link on an interrupt driven PHY was not coming up if the
>> Ethernet cable was plugged before the Ethernet interface was brought up.
>>
>> The PHY state machine seems to be stuck from RUNNING to AN state
>> with no new interrupts from the PHY. So it doesn't know when the
>> PHY Auto-negotiation has been completed and doesn't transition to RUNNING
>> state with ANEG done thus netif_carrier_on() is never called.
>>
>> NOTE: genphy_config_aneg() will not restart PHY Auto-negotiation of
>> advertisement parameters didn't change.
>>
>> Fix this by scheduling the PHY state machine in phy_start_aneg().
>> There is no way of knowing in phy.c whether auto-negotiation was
>> restarted or not by the PHY driver so we just wait for the next
>> poll/interrupt to update the PHY state machine.
>>
>> Fixes: 3c293f4e08b5 ("net: phy: Trigger state machine on state change and not polling.")
>> Cc: stable <stable@xxxxxxxxxxxxxxx> # v4.9+
>> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
>
> Reviewed-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
>
Thanks for the review, but there are a still few unanswered questions in the parallel thread.
Can you please clarify those first before this patch gets picked? Thanks.

cheers,
-roger