<Please don't post HTML email, the mailing lists reject your messages that way> On Fri, Apr 20, 2012 at 09:39:37PM +0530, Anil Nair wrote: > > > >USB ports on a hub are all enumerated the same, but the root hubs > >aren't, and sometimes hubs on the same bus are not as well. > > > Does every device assigned a port number serially, that is in increasing > order? Yes. > If a USB port number is assigned to a USB device then are other USB devices > able to use it, > if connected USB device is Disconnected? It can, why? USB devices don't care about their device number. > >But usually, things do come up in the same way all the time, so > >depending on your use case, you can rely on this, but it is recommended > >that you look for something else a bit more unique, like a serial number > >on a device (if it is present), if you wish to uniquely identify a > >device all the time. > > > Does the Linux Kernel keeps the history of connected devices? So that next > time, the same USB device get assigned the same USB port number. No. I think you are confusing port number with the USB device number, both of which mean nothing to a USB device at all, and they shouldn't to anyone else. greg k-h -- 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
