Having same issues on System76 Galago UltraPro (same hardware as Clevo W740SU and Schenker S413), running Arch Linux x64 (kernel 3.14.3 from official repo). After reading comments here and playing with xhci quirks, I found a combination, which works: XHCI_SPURIOUS_WAKEUP and XHCI_SPURIOUS_REBOOT (both at the same time, individually they are not fixing the issue). Not to rebuild the kernel, I just passed required quirks as module options:
Having same issues on System76 Galago UltraPro (same hardware as Clevo W740SU and Schenker S413), running Arch Linux x64 (kernel 3.14.3 from official repo). After reading comments here and playing with xhci quirks, I found a combination, which works: XHCI_SPURIOUS_ WAKEUP and XHCI_SPURIOUS_ REBOOT (both at the same time, individually they are not fixing the issue). Not to rebuild the kernel, I just passed required quirks as module options:
cat /etc/modprobe. d/xhci. conf
options xhci-hcd quirks=270336
where 270336 = (1 << 18) + (1 << 13). After rebuilding ramdisk and rebooting shutdown works fine.
Hopefully this will be helpful for somebody.