On Sat, Oct 19, 2013 at 9:45 PM, Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx> wrote: > On Sat, Oct 19, 2013 at 03:36:58PM -0400, Alan Stern wrote: >> On Fri, 18 Oct 2013, Andiry Xu wrote: >> >> > Interesting. I used the following commands: >> > >> > #echo disabled > /sys/bus/pci/devices/0000:00:14.0/power/wakeup >> > #echo enabled > /sys/bus/pci/devices/0000:00:14.0/usb3/power/wakeup >> > #echo enabled > /sys/bus/pci/devices/0000:00:14.0/usb4/power/wakeup >> > >> > And a device plugging to xHCI port does wakeup the system from S3. >> > The test is performed on a Intel HM76 chipset. >> > >> > So it means xHCI driver should clear wakeup flags for suspended ports >> > in this case, just like ehci driver does. Correct? >> >> Yes, I agree. >> >> Sarah, is this worth reporting to the Intel chipset engineers as a bug? > > I'm not sure. I'll have to take a closer look at it after I get back > from LinuxCon/Kernel Summit and vacation (which won't be until after Nov > 6th, FYI). > > I do agree that it should be fixed. I've stared at that code a couple > times and tired to figure out why it unconditionally sets the wake on > flags. I suppose it might even explain some of the spurious wakeups > we've seen on xHCI host controllers, although those systems seem to > reboot on shutdown even if there's no port changes. > > Also, hi Andiry! I haven't seen you on the mailing list in a while. :) > Are you working for another company on the kernel again? > Hi Sarah, nice to see you again:) I'm still working on my PhD degree at UC San Diego. I'm working with storage devices on Linux, but not on driver. With fast non-volatile storage - perhaps as fast as DRAM, all the software overhead is significant, including the kernel switch, file system and interrupt handler, etc. So I'm trying to "bypass" the kernel entirely rather than working on it. I'm quite busy with my study so I only look at LKML occasionally. That's why it looks like I disappeared. Thanks for all the work you've done to fix my code. Thanks, Andiry -- 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
