Messages in this thread |  | | Date | Wed, 20 Nov 2013 22:05:07 +0100 | From | Sebastian Hesselbarth <> | Subject | Re: [PATCH RFC v1 4/7] net: phy: suspend unused PHYs on mdio_bus in late_initcall |
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On 11/20/2013 09:58 PM, Florian Fainelli wrote: > 2013/11/20 Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>: >> Since phy_attach ensures PHYs are resumed, we can now suspend all >> PHYs that have no attached netdev after initcalls. > > I do like the idea, but I think you might want to make sure that the > MDIO bus suspend policy was set to "auto" (which is the default afair) > not to expose unexpected behavior.
Ok, TBH I haven't looked through all of phy internals. If we are fine with the overall approach, I could use some guidance in the individual patches and policies.
>> >> 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/phy/mdio_bus.c | 27 +++++++++++++++++++++++++++ >> 1 files changed, 27 insertions(+), 0 deletions(-) >> >> diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c >> index 5617876..10eba58 100644 >> --- a/drivers/net/phy/mdio_bus.c >> +++ b/drivers/net/phy/mdio_bus.c >> @@ -320,6 +320,33 @@ static int mdio_bus_match(struct device *dev, struct device_driver *drv) >> (phydev->phy_id & phydrv->phy_id_mask)); >> } >> >> +static int mdio_bus_suspend_unused(struct device *busdev, void *data) >> +{ >> + struct mii_bus *bus = to_mii_bus(busdev); >> + struct phy_device *phydev; >> + struct phy_driver *phydrv; >> + int i; >> + >> + for (i = 0; i < PHY_MAX_ADDR; i++) { >> + if (!bus->phy_map[i]) >> + continue; >> + >> + phydev = to_phy_device(&bus->phy_map[i]->dev); >> + phydrv = to_phy_driver(phydev->dev.driver); >> + if (!phydev->attached_dev && phydrv && phydrv->suspend) >> + phy_suspend(phydev); >> + } >> + >> + return 0; > > You might want to reuse mdio_bus_phy_may_suspend() here to have a > central place checking for phydev->attached_dev and phydrv->suspend > just in case we need to add more callbacks in the future or implicit > PHY state machine hooks. That might also take care of my concern > expressed above.
Unfortunately, mdio_bus_phy_may_suspend() doesn't help here. It will correctly tell that unconnected PHYs may_suspend but also that PHYs connected to PM aware drivers may_suspend.
I tried it and it will also suspend the PHY taken by mv643xx_eth.
But actually, as phy_suspend/resume check for phydrv->suspend themselves, we can just call it on !phydev->attached_dev and remove the additional checks.
>> +} >> + >> +static int mdio_bus_class_suspend_unused(void) >> +{ >> + return class_for_each_device(&mdio_bus_class, NULL, NULL, >> + mdio_bus_suspend_unused); >> +} >> +late_initcall_sync(mdio_bus_class_suspend_unused); >> + >> #ifdef CONFIG_PM >> >> static bool mdio_bus_phy_may_suspend(struct phy_device *phydev) >> -- >> 1.7.2.5 >> >> >> _______________________________________________ >> linux-arm-kernel mailing list >> linux-arm-kernel@lists.infradead.org >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > > >
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