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My USB devices were working fine. Then, I tried to connect a USB hub, and now they're all gone. I played around with "insmod", "rmmod", and "modprobe", but probably just made things worse. I also plugged and unplugged devices and probably did some other stupid things.

Things I've tried (as root):

# lsusb -v 

[no output] 

# ls -laR /proc/bus/usb/ 
/proc/bus/usb/: 
total 0 
drwxr-xr-x 4 root root 0 2013-07-31 11:17 ./ 
dr-xr-xr-x 6 root root 0 2013-08-02 22:57 ../ 
dr-xr-xr-x 2 root root 0 2013-07-31 11:17 001/ 
dr-xr-xr-x 2 root root 0 2013-07-31 11:17 002/ 
-r--r--r-- 1 root root 0 2013-08-02 22:46 devices 

/proc/bus/usb/001: 
total 0 
dr-xr-xr-x 2 root root  0 2013-07-31 11:17 ./ 
drwxr-xr-x 4 root root  0 2013-07-31 11:17 ../ 
-rw-r--r-- 1 root root 43 2013-07-31 11:17 001 

/proc/bus/usb/002: 
total 0 
dr-xr-xr-x 2 root root  0 2013-07-31 11:17 ./ 
drwxr-xr-x 4 root root  0 2013-07-31 11:17 ../ 
-rw-r--r-- 1 root root 43 2013-07-31 11:17 001 

# find /proc/bus/usb -type f | xargs cat 

cat: /proc/bus/usb/002/001: No such device 
cat: /proc/bus/usb/001/001: No such device 

T:  Bus=02 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=480 MxCh= 2 
B:  Alloc=  0/800 us ( 0%), #Int=  0, #Iso=  0 
D:  Ver= 2.00 Cls=09(hub  ) Sub=00 Prot=00 MxPS=64 #Cfgs=  0 
P:  Vendor=1d6b ProdID=0002 Rev= 2.06 

T:  Bus=01 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=480 MxCh= 2 
B:  Alloc=  0/800 us ( 0%), #Int=  0, #Iso=  0 
D:  Ver= 2.00 Cls=09(hub  ) Sub=00 Prot=00 MxPS=64 #Cfgs=  0 
P:  Vendor=1d6b ProdID=0002 Rev= 2.06 

Short of rebooting, what commands/tools can I try to restore my USB devices?

EDIT: back when I had RedHat 7.3, this would sometimes work:

rmmod usb-uhci 
rmmod usb-storage 
rmmod scanner 
rmmod usbcore 
insmod ehci-hcd 
insmod usb-storage 
insmod usb-uhci 

(I realize there's no "insmod scanner" above, but it seemed to work).

However, some of these modules aren't available in FC11, and I think modprobe is the correct way to load/unload modules now. I even did "modprobe -l" and looked for usb-like things, but I think that made things worse, not better.

share|improve this question
    
Did you try it with out the hub? Is the hub self powered, does it have a cord that plugs into an outlet? USB 2.0 only offers 500ma of power and the hub plus 2 probably takes more. What are the other 2 usb devices? –  cybernard Aug 4 '13 at 1:13
    
I know you don't want to reboot, but if you overloaded the USB controller, it may take a reboot to reinitiize it. –  spuder Aug 4 '13 at 1:18
    
@cybernard Oh, I removed the hub entirely, and just put back the original devices. There are actually three devices connected: a hard drive, a scanner, and a printer. I don't know which two it's seeing. –  barrycarter Aug 4 '13 at 1:39
    
@barrycarter Why not reboot? What version of kernel do you have? uname -r –  cybernard Aug 4 '13 at 3:27
    
@cybernard 2.6.30.10-105.2.23.fc11.i686.PAE -- I guess rebooting isn't such a big deal, but I loathe it. Of course, we have thunderstorms forecast for the next 4 days, so this problem may just take care of itself... –  barrycarter Aug 4 '13 at 4:21
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