Re: [PATCH net-next v4 4/9] net: dsa: microchip: ksz9477: add Wake on LAN support

[Oleksij Rempel]

On Mon, Oct 16, 2023 at 08:37:50AM -0700, Florian Fainelli wrote:
> [snip]
> > +void ksz9477_get_wol(struct ksz_device *dev, int port,
> > +		     struct ethtool_wolinfo *wol)
> > +{
> > +	u8 pme_ctrl, pme_conf;
> > +	int ret;
> > +
> > +	ret = ksz_read8(dev, REG_SW_PME_CTRL, &pme_conf);
> > +	if (ret)
> > +		return;
> > +
> > +	if (!(pme_conf & PME_ENABLE))
> > +		return;
> 
> I suppose this works beause you have separate enable bits for WOL_LINKUP,
> WOL_ENERGY and WOL_MAGICPKT, you could have also left the setting of the
> PME_ENABLE bit to the set_wol() routine provided that wol->wolopts is
> non-zero.

Setting the PME_ENABLE bit in the set_wol() function might imply that it
should also be cleared within set_wol(), necessitating refcounting due
to its global bit nature.

As an alternative, the reading of the REG_SW_PME_CTRL register could be
replaced by checking the wakeup_source variable, which might result in
some optimization.

Regards,
Oleksij
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