On 11 December 2012 12:53, Ming Lei [off-list ref] wrote:

On Tue, Dec 11, 2012 at 6:27 PM, Oliver Neukum [off-list ref] wrote:

quoted

So they can autosuspend if the interface is up and no cable is plugged
in?

From the open datasheet, that is the suspend 1 mode, which is supported
by all LAN95xx devices. Steve, correct me if I am wrong.

All parts support SUSPEND1, but some parts can't 100% reliably wake on
ENERGYON - some link partners will wake them but others won't.  The
driver already detects parts that work reliably with all link partners
and sets the FEATURE_PHY_NLP_CROSSOVER feature flag.

I didn't block these devices from configuring WOL, because they do
work in *some* cases and the user is explicitly requesting to wake the
system so we try to do that (and sometimes succeed).

quoted

quoted

I suggest to introduce link-off triggered runtime suspend for these
usbnet devices(non-LAN9500A device, devices which don't support
USB auto-suspend), and I have posted one patch set before[1].
If no one objects that, I'd like to post them again with some fix and
update for checking link after link_reset().

If you can get rid of a periodic work this would be great.

For the LAN95xx devices, the periodic work isn't needed because
they may generate remote wakeup when link change is detected.

As above, some parts will do this but some will not.  I think we
should only consider sleeping the part if we're sure it'll wake up
when a cable is connected!

-- 
Steve Glendinning