Re: ehci_hcd causes box to resume immediately after suspend to RAM
"Rafael J. Wysocki" <[email protected]>
| Newsgroups | gmane.linux.usb.devel,gmane.linux.power-management.general |
|---|---|
| Message-ID | <[email protected]> |
On Sunday, 3 June 2007 17:31, Alan Stern wrote: > On Sun, 3 Jun 2007, Rafael J. Wysocki wrote: > > > Hi, > > > > One of my test boxes suspends to RAM just fine except that if ehci_hcd is > > loaded before the suspend, the box resumes immediately after going to sleep. > > Evidently the hardware thinks a wakeup event has occurred. It is > possible to disable remote wakeup via sysfs, but it would be more > interesting to find out the real reason for the wakeup. > > I don't know how to go about doing that, however. It might be some > interaction at the ACPI level, and it might involve the PCI PME# > signal. > > Do you have any USB devices attached when you suspend? > > You can try using the patch below to see what happens when you manually > suspend the controller. It enables PCI devices to respond to the > legacy power/state attribute. You should look at what "lspci -vv" says > about the controller's power management signals, both before and after > suspending the PCI device entry. It works as expected, AFAICS. That is, after I echo '2' to the 'state' file, it shows that the controller is in D3. I've tried to suspend with the controller in that state, but it's resumed immediately, as before. > Maybe also see what ACPI reports. How can I see that? Rafael -- "Premature optimization is the root of all evil." - Donald Knuth ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel