On Fri, 19 Dec 2008, Alan Stern wrote: > On Fri, 19 Dec 2008, Zhang Rui wrote: > > > device parallel resume support for PCI devices > > There are some PCI devices which won't work right if they are resumed > in parallel. The example I have in mind is a USB host controller > device with both a high-speed EHCI controller function and some > companion low/full-speed UHCI or OHCI controller functions. The EHCI > driver relies on the fact that the EHCI controller has a higher > function number and therefore is resumed _after_ the companion > controllers. > > We need a way to express dependencies like this between devices. Or at > least, there has to be a way to prevent certain devices from resuming > in parallel. Perhaps the most pragmatic approach would be to identify which devices benefit the most from parallel resume, and use some hooks so that those device drivers can be optimized to resume in parallel while everything else takes the existing serialized path? -- Len Brown, Intel Open Source Technology Center _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
