Re: [PATCH] net: phy: micrel: reconfigure the phy on resume

On Thu 2021-01-14 12:05:21, Heiner Kallweit wrote:

On 14.01.2021 11:41, Claudiu.Beznea@microchip.com wrote:

quoted

On 14.01.2021 12:25, Russell King - ARM Linux admin wrote:

quoted

As I've said, if phylib/PHY driver is not restoring the state of the
PHY on resume from suspend-to-ram, then that's an issue with phylib
and/or the phy driver.

In the patch I proposed in this thread the restoring is done in PHY driver.
Do you think I should continue the investigation and check if something
should be done from the phylib itself?

It was the right move to approach the PM maintainers to clarify whether
the resume PM callback has to assume that power had been cut off and
it has to completely reconfigure the device. If they confirm this
understanding, then:

Power to some devices can be cut during s2ram, yes.

- the general question remains why there's separate resume and restore
  callbacks, and what restore is supposed to do that resume doesn't
  have to do

You'll often have same implementation, yes.

- it should be sufficient to use mdio_bus_phy_restore also as resume
  callback (instead of changing each and every PHY driver's resume),
  because we can expect that somebody cutting off power to the PHY
  properly suspends the MDIO bus before

If restore works with power cut and power not cut then yes, you should
get away with that.

Best regards,
								Pavel
-- 
http://www.livejournal.com/~pavelmachek