Under what conditions is phy_device "adjust_link()" called?

Under what conditions is phy_device "adjust_link()" called?

[rpjday]

I can see from the documentation that the callback adjust_link() is invoked
"for the enet controller to respond to changes in the link state." Is there
a specific list of the events that would generate such a change? Are we
talking initially opening the device, ifup/ifdown, physically unplugging
from the port, some or all of the above?

Not a network expert (yet), so I'm still digging through the code. Thanks.

rday

Re: Under what conditions is phy_device "adjust_link()" called?

[Florian Fainelli]

On 08/16/2018 10:26 AM, rpjday@crashcourse.ca wrote:
> 
> I can see from the documentation that the callback adjust_link() is invoked
> "for the enet controller to respond to changes in the link state." Is there
> a specific list of the events that would generate such a change? Are we
> talking initially opening the device, ifup/ifdown, physically unplugging
> from the port, some or all of the above?

adjust_link() is typically called on transitions from link UP to DOWN
and DOWN to UP. This may include the initial configuration of the PHY
during e.g: phy_connect() and then typically when an event occurs than
requires a re-configuration of the MAC: link parameters (speed, status,
duplex, pause) changed.

> 
> Not a network expert (yet), so I'm still digging through the code. Thanks.

Reading the PHY state machine under drivers/net/phy/phy.c will make this
more clear IMHO.
-- 
Florian

Re: Under what conditions is phy_device "adjust_link()" called?

[Andrew Lunn]

On Thu, Aug 16, 2018 at 11:59:19AM -0700, Florian Fainelli wrote:
> On 08/16/2018 10:26 AM, rpjday@crashcourse.ca wrote:
> > 
> > I can see from the documentation that the callback adjust_link() is invoked
> > "for the enet controller to respond to changes in the link state." Is there
> > a specific list of the events that would generate such a change? Are we
> > talking initially opening the device, ifup/ifdown, physically unplugging
> > from the port, some or all of the above?
> 
> adjust_link() is typically called on transitions from link UP to DOWN
> and DOWN to UP. This may include the initial configuration of the PHY
> during e.g: phy_connect() and then typically when an event occurs than
> requires a re-configuration of the MAC: link parameters (speed, status,
> duplex, pause) changed.

Just adding to that, if you have a 10G PHY, the MAC-PHY interface mode
can also change, e.g. SGMII for 10/100/1000, and 10GBase-T for 10G,
etc.

	Andrew