On Tuesday, November 01, 2011, Linus Torvalds wrote: > On Tue, Nov 1, 2011 at 2:30 PM, Rafael J. Wysocki <rjw@xxxxxxx> wrote: > > > > However, with commit 379021d5c0 reverted, do you still see wakeup > > events on the _other_ devices when plugging something into an xHCI port? > > No. With plain 3.1 (which was what I was testing at the KS), plugging > in the USB thing didn't do *anyting*. No messages - not xhci, not > ehci, nothing. Hmm. The fact that you see the EHCI "resume" messages with commit 379021d5c0 applied means that the EHCI really does have the PME Status bit set when it's being polled, because the resume wouldn't be triggered otherwise. So, it _seems_ like plugging the USB device into the xHCI port causes the EHCI's PME Status bit to be set as well. You can try to confirm this by looking at the PME Status bits of the devices in question under 3.1 (ie. without commit 379021d5c0) before (they should be unset) and after plugging in the USB device (the xHCI's PME status should be set, the EHCI's one may or may not be set). Simply look at the status line under the PM capability in the output of "lspci -vv" for each interesting device. Now, the fact that you don't see any events with plain 3.1 means that either the PME messages don't reach the root complex (which is unlikely, but not unseen), or they reach it, but they fail to cause any events to be signaled. It is hard to say which is the case without knowing what's really going on on the bus, though. I wonder if plugging a device into a known non-xHCI USB port triggers any events with plain 3.1? Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
