Hi, I'm experiencing problem with USB ports - they shuts down after kernel loads - and I've found partial solution - few times switching auto/on on power control of xHCI controller. I want to figure out what is wrong with that and where I can change something to resolve this properly. Where I can see some messages from USB drivers, or turn on more verbose log mode for kernel so I can see what happens just before ports start working? Below are more details. Bug report: https://bugzilla.kernel.org/show_bug.cgi?id=74071 Symptoms: USB ports stop working (power off) just after boot loader loads kernel. They don't turn on even after 10 minuts after boot. Undeterminable count of switching value of xHCI controlller power/control in /sys to "on" and "auto" and back again and waiting few seconds turns USB ports ON until reboot. Observations: - Is not HW problem (Windows works, before boot (in BIOS) works as well) - With acpi=off USB ports do not shuts down. - With usbcore.autosuspend=-1 nothing changes. - Is not distro specific (same behavior in OpenSUSE, Ubuntu, Debian, different versions - tried with USB live stick) - Is not BIOS/EFI specific, neither arch i686/amd64 - each combination behaves the same - No specific message in dmesg about error with USB - After switching /sys/bus/pci/devices/_xHCI controller address_/power/control to auto, power on USB starts turning on and off (cca in 0.25s intervals). After undetermined count of switches from "auto" to "on" and back and waiting up to 10 seconds in every "auto" state, power stabilizes and driver recognizes connected devices (not before even for short on power states). HW: Lenovo ThinkPad Twist 3347-26G, BIOS v1.65, Core i5-3317U Ivy Bridge (2x USB3.0 ports, ps2 laptop trackpoing, internal USB webcam, synaptic touchpad, keyboard) USB devices - msi usb2.0 hub -> rapoo keyboard, zelman optical mouse (same even for directly connected - no problem in HW) Running OS: Ubuntu 14.04, UEFI boot (for testing) Thank you very much Lukas Dolezal -- 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
