Re: [PATCH net-next v1 3/4] net: phy: do not force EEE support

On Mon, Feb 20, 2023 at 02:21:42PM +0000, Russell King (Oracle) wrote:

On Mon, Feb 20, 2023 at 02:56:04PM +0100, Oleksij Rempel wrote:

quoted

 	if (data->eee_enabled) {
+		phydev->eee_enabled = true;
 		if (data->advertised)
-			adv[0] = data->advertised;
-		else
-			linkmode_copy(adv, phydev->supported_eee);
+			phydev->advertising_eee[0] = data->advertised;

There is a behavioural change here that isn't mentioned in the patch
description - if data->advertised was zero, you were setting the
link modes to the full EEE supported set. After this patch, you
appear to leave advertising_eee untouched (so whatever it was.)

Which is the correct behaviour for this interface?

Hm.. ethtool do not provide enough information about expected behavior.
Here is my expectation:
- "ethtool --set-eee lan1 eee on" should enable EEE if it is disabled.
- "ethtool --set-eee lan1 advertise 0x10" should change set of
  advertised modes.
- a sequence of "..advertise 0x10", "..eee on", "eee off" should restore
  preconfigured advertise modes. advertising_eee instead of
  supported_eee.

Seems like there is still one missing use case: if advertising_eee is
zero, we should use supported_eee value for "...eee on" case.

Other ideas?
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