On Sat, 7 Jun 2014, Mildred Ki'Lya wrote: > On mer., 2014-05-21 at 13:50 -0400, Alan Stern wrote: > > On Wed, 21 May 2014, Mildred Ki'Lya wrote: > > > > > Hi, > > > > > > I have a problem with a USB device (4255:1000), running various kernels > > > from 3.12.6 (Fedora) up to 2.14.4 (ArchLinux). When I connect the > > > device, it appears all right. But after a few seconds of idle, it > > > disconnects itself. > ... > > > > It's possible that the device can't handle Link Power Management. > > You can test this by writing 0 to the usb2_hardware_lpm file in the > > device's sysfs power directory: > > > > echo 0 >/sys/bus/usb/device/1-6/power/usb2_hardware_lpm > > > > Thank you for your answer. I didn't have the opportunity to test until > today, and unfortunately I couldn't try this. There is no file > usb2_hardware_lpm for that device. It's possible the device doesn't > support this feature. > > Do you have an idea of what else could go wrong with this device? No, I don't. It might just be buggy. Alan Stern -- 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
