On Thu, 24 Mar 2011 09:59:52 -0400 (EDT) Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > On Wed, 23 Mar 2011, jacob pan wrote: > > > Hi, > > > > I have a dumb question about enabling EHCI runtime PM with PCI > > subsystem. It seems core code in hci-pci.c provides the runtime call > > backs in usb_hcd_pci_pm_ops. But I don't see that being used in > > case of EHCI suspend/resume. > > > > I must have missed something, can someone explain how this should > > work? > > > > On our platform, we need to put EHCI in PCI D0i3 hot when we suspend > > root hub so that the block can be put into low power mode. I guess > > we also need platform specific functions to set the PCI Dx state > > during runtime suspend. > > No. As Ming explained, you only need to enable runtime PM for the > controller. For example: > > echo auto >/sys/bus/pci/devices/0000:00:1d.7/power/control > > Substitute the appropriate device name in the path above. Thanks all for explaining this. I took for granted PCI PM is in auto by default. Jacob -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
