Messages in this thread |  | | From | Florian Fainelli <> | Date | Wed, 20 Nov 2013 12:48:08 -0800 | Subject | Re: [PATCH RFC v1 7/7] net: cpsw: resume/suspend PHY on port start/stop |
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2013/11/20 Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>: > Network PHYs consume a noticable amount of power. This adds phy_resume > on slave_open and phy_suspend on slave_stop to save this power if the > port is down anyway. > > Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> > --- > Cc: David S. Miller <davem@davemloft.net> > Cc: netdev@vger.kernel.org > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-kernel@vger.kernel.org > --- > drivers/net/ethernet/ti/cpsw.c | 2 ++ > 1 files changed, 2 insertions(+), 0 deletions(-) > > diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c > index 90d41d2..f1dc54f 100644 > --- a/drivers/net/ethernet/ti/cpsw.c > +++ b/drivers/net/ethernet/ti/cpsw.c > @@ -1013,6 +1013,7 @@ static void cpsw_slave_open(struct cpsw_slave *slave, struct cpsw_priv *priv) > } else { > dev_info(priv->dev, "phy found : id is : 0x%x\n", > slave->phy->phy_id); > + phy_resume(slave->phy); > phy_start(slave->phy);
Cannot phy_start() figure this out for us based on the internal PHY device state machine?
I would imagine that you would want to call phy_suspend/resume from an Ethernet driver's PM suspend/resume callbacks to make sure that the PHY also enters a low power mode, but I do not want to have to remember that I need to call phy_resume before phy_start for instance. As of today we have PHY_HALTED/PHY_RESUMING, and I think we certainly need at least a PHY_SUSPENDED state to help us with that.
> > /* Configure GMII_SEL register */ > @@ -1081,6 +1082,7 @@ static void cpsw_slave_stop(struct cpsw_slave *slave, struct cpsw_priv *priv) > if (!slave->phy) > return; > phy_stop(slave->phy); > + phy_suspend(slave->phy);
Same here, why is not that hidden in phy_stop? If there is any fear that this breaks setups where WoL is used or such, we could add a new argument to phy_connect() and friends which says whether it is okay to auto-suspend the PHY upon PHY_stop
> phy_disconnect(slave->phy); > slave->phy = NULL; > } > -- > 1.7.2.5 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
-- Florian
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