On Tue, 4 Jun 2019 at 23:07, Andrew Lunn <and...@lunn.ch> wrote: > > On Tue, Jun 04, 2019 at 10:58:41PM +0300, Vladimir Oltean wrote: > > Hi, > > > > I've been wondering what is the correct approach to cut the Ethernet link > > when the user requests it to be administratively down (aka ip link set dev > > eth0 down). > > Most of the Ethernet drivers simply call phy_stop or the phylink equivalent. > > This leaves an Ethernet link between the PHY and its link partner. > > The Freescale gianfar driver (authored by Andy Fleming who also authored the > > phylib) does a phy_disconnect here. It may seem a bit overkill, but of the > > extra things it does, it calls phy_suspend where most PHY drivers set the > > BMCR_PDOWN bit. Only this achieves the intended purpose of also cutting the > > link partner's link on 'ip link set dev eth0 down'. > > Hi Vladimir > > Heiner knows the state machine better than i. But when we transition > to PHY_HALTED, as part of phy_stop(), it should do a phy_suspend(). > > Andrew
Hi Andrew, Florian, Thanks for giving me the PHY_HALTED hint! Indeed it looks like I conflated two things - the Ehernet port that uses phy_disconnect also happens to be connected to a PHY that has phy_suspend implemented. Whereas the one that only does phy_stop is connected to a PHY that doesn't have that... I thought that in absence of .suspend, the PHY library automatically calls genphy_suspend. Oh well, looks like it doesn't. So of course, phy_stop calls phy_suspend too. But now the second question: between a phy_connect and a phy_start, shouldn't the PHY be suspended too? Experimentally it looks like it still isn't. By the way, Florian, yes, PHY drivers that use WOL still set BMCR_ISOLATE, which cuts the MII-side, so that's ok. However that's not the case here - no WOL. Regards, -Vladimir
