On Tue, 15 Jan 2013, makuda wrote: > Alan Stern <stern@...> writes: > > > > > On Fri, 17 Dec 2010, Alessio Sangalli wrote: > > > > > On 12/17/2010 07:42 AM, Alan Stern wrote: > > > > > > > Anyway, you can force individual root-hub ports to be dedicated to the > > > > companion controller by using sysfs. For example, let's say you wanted > > > > port 4 on bus 1 always to run at full or low speed. You would do it > > > > by: > > > > > > > > # echo 4>/sys/bus/usb/devices/usb1/../companion > > > > > > Ok the problem is that in earlier versions of the kernel this was > > > something like: > > > > > > /sys/class/usb_host/usb_hostXXX/companion > > > > > > Hi, very silly question. What is exacly the meaning of double dot in the path > here > > # echo 4>/sys/bus/usb/devices/usb1/../companion > > I used to treat .. as a parent directory but here it does not have sense for > me, but I'm rather newcomer in linux ... That's what it means: the parent directory. It isn't the same as /sys/bus/usb/devices/companion, though, because the usb1 entry is a symbolic link. 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
