On Fri, Aug 3, 2018 at 1:15 AM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > On Thu, 2 Aug 2018, Muni Sekhar wrote: > >> I see that CONFIG_PM_RUNTIME & CONFIG_USB_SUSPEND are not enabled. Is that fine? > > The CONFIG_PM_RUNTIME and CONFIG_USB_SUSPEND symbols are no longer > used. > >> The device is using btusb driver. Does unloading the driver helps? > > It should. > >> I ran ‘lsof’ and and I see that the USB device was being held open by >> fwupd, not sure what is ‘fwupd’? > > It is a firmware update daemon. > >> # sudo lsof +D /dev/bus/usb >> lsof: WARNING: can't stat() fuse.gvfsd-fuse file system /run/user/1000/gvfs >> Output information may be incomplete. >> COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME >> fwupd 1631 root 49u CHR 189,67 0t0 547 /dev/bus/usb/001/068 >> >> >> So I killed that process(fwupd), but still device is not going to SUSPEND mode. >> >> # sudo lsof +D /dev/bus/usb >> lsof: WARNING: can't stat() fuse.gvfsd-fuse file system /run/user/1000/gvfs >> Output information may be incomplete. >> >> >> # cat /sys/bus/usb/devices/1-1.3/power/runtime_status >> active > > Well, keeping the device might or might not prevent it from being > suspended. It all depends on how the driver is written. But if you > unload the driver then the device certainly ought to go into runtime > suspend. Unloading the driver and killing the 'fwupd' daemon resulted that device to go into runtime suspend. Here I noticed that both the operations(i.e. rmmod btusb & kill -9 <pid of fwupd>) are mandatory to device to go into runtime suspend. I'd like to understand how the driver & daemon are preventing the device to go into suspend mode, can you please explain me on this? > > Alan Stern > -- Thanks, Sekhar -- 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
