On Thursday 07 October 2004 2:19 pm, Stefan Rompf wrote: > Hi, > > ehci_hub_resume() reads the hub port registers during resume. However, on S3
Well there's a conceptual problem that keeps coming up lately... encouraged by the current APIs, to be sure! The device doesn't enter S3 .. it enters PCI D3hot state. If the system entered S3, then the device would have stayed in D3hot until resume. The problem is that when it's resumed after swsusp, it's really resuming from D3cold state ... and sometimes not even one of those, since BIOS may have mucked with the hardware. (Except for the S4BIOS suspend routes, I think...) > or swsusp the root hub loses power, making read data invalid and forcing the > user to replug all devices. Saving the data in memory during suspend helps - > at least for my i855gm based notebook. The OHCI driver (in the current BK-USB tree) has code to specifically recognize some of the Funky BIOS States involved. I haven't yet made time to see what those states are for EHCI; it's on my list... > There are still issues. When uhci resumes before ehci, it reconnects all > devices. That's not true for a "real resume" -- from D3hot. But after swsusp, this shows another set of Funky BIOS States ... so there are UHCI states to handle, and EHCI states to handle, and combinations to handle, including ones like yours (BIOS doesn't seem to grok EHCI), or where the BIOS ignores both controllers, or where it also handles EHCI... No wonder I wasn't looking forward to getting that to work. :( > Also, I need a rather bad hack that ignores pci_set_power_state() > return values in usb_hcd_pci_suspend(), but that is all not directly related > to my patch. I had a separate patch with changes in that area, which I've posted a couple times now and also sent with this batch: http://marc.theaimsgroup.com/?l=linux-kernel&m=109692668310738&w=2 http://marc.theaimsgroup.com/?l=linux-kernel&m=109692668228442&w=2 http://marc.theaimsgroup.com/?l=linux-kernel&m=109692610403412&w=2 http://marc.theaimsgroup.com/?l=linux-kernel&m=109692915107429&w=2 http://marc.theaimsgroup.com/?l=linux-kernel&m=109692881326178&w=2 Unfortunately it looks like some more substantial PM core changes will be needed than just the two wakeup-support bits added by those patches, so it'll take a while to make everything integrate reasonably. - Dave > Signed-off-by: Stefan Rompf ([EMAIL PROTECTED]) > > Stefan > ------------------------------------------------------- This SF.net email is sponsored by: IT Product Guide on ITManagersJournal Use IT products in your business? Tell us what you think of them. Give us Your Opinions, Get Free ThinkGeek Gift Certificates! Click to find out more http://productguide.itmanagersjournal.com/guidepromo.tmpl _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
