On 04/13/2012 01:46 PM, Alan Stern wrote: > On Fri, 13 Apr 2012, Stephen Warren wrote: >> I've tested the patch, and can unplug a USB device, wait 10 seconds, >> then plug it back in, and everything works as expected. >> >> However, I don't notice /sys/devices/.../power/runtime_status ever >> saying anything other than active, and I can't cat autosuspend_delay_ms, >> so I assume I'm still not triggering the path you want me to test. I do >> have PM_RUNTIME turned on. Any ideas? Do I need some patch to the USB >> core to enable this? I tested on next-20120413 plus a few local patches. > > autosuspend_delay_ms isn't relevant here; the controller should be > suspended with no delay as soon as the root hub suspends. No other > patches should be needed; it sounds like you're doing everything right. > > If you enable CONFIG_PM_ADVANCED_DEBUG along with CONFIG_PM_RUNTIME, > what do all the other power/runtime_* files show? The EHCI controller's active_kids count stays at 1 all the time. I assume that's the root USB hub device. Looking in its power/ directory, I see that even when nothing is plugged in, runtime_status==enabled, even with no active_kids or runtime_usage: [ 242.611209] usb 3-1: USB disconnect, device number 4 root@ilyich:/sys/devices/tegra-ehci.2/usb3/power# cat async enabled root@ilyich:/sys/devices/tegra-ehci.2/usb3/power# cat autosuspend_delay_ms 0 root@ilyich:/sys/devices/tegra-ehci.2/usb3/power# cat control auto root@ilyich:/sys/devices/tegra-ehci.2/usb3/power# cat runtime_active_kids 0 root@ilyich:/sys/devices/tegra-ehci.2/usb3/power# cat runtime_active_time 262840 root@ilyich:/sys/devices/tegra-ehci.2/usb3/power# cat runtime_enabled enabled root@ilyich:/sys/devices/tegra-ehci.2/usb3/power# cat runtime_status active root@ilyich:/sys/devices/tegra-ehci.2/usb3/power# cat runtime_suspended_time 0 root@ilyich:/sys/devices/tegra-ehci.2/usb3/power# cat runtime_usage 0 Are the wakeup_* files in this directory relevant? wakeup says "disabled", and all the others are empty. -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html