#12158 BLOC 4-softw: xo-4 -- USB "cannot reset port" after boot

Zarro Boogs per Child bugtracker at laptop.org
Tue Nov 26 16:45:17 EST 2013

#12158: xo-4 -- USB "cannot reset port" after boot
           Reporter:  pgf        |       Owner:  cjb                               
               Type:  defect     |      Status:  reopened                          
           Priority:  blocker    |   Milestone:  4-software                        
          Component:  kernel     |     Version:  Development source as of this date
         Resolution:             |    Keywords:  XO-4, USB                         
        Next_action:  reproduce  |    Verified:  0                                 
Deployment_affected:             |   Blockedby:                                    
           Blocking:             |  

Comment(by Quozl):


 The laptop has a USB hub chip between the CPU and the ports.

 Both port 2 and port 3 were in your log, and the problem is persisting
 over power cycle of the USB hub chip, so it seems slightly different.

 Please try a full power down, with all cables disconnected, including
 battery removal for 15 seconds.  This will test for ESD induced CMOS
 lockup, and broken devices that backfeed the port.

 Could you please test in firmware?  I'm interested in the boot sequence to
 the ok prompt, the output of "p2" and "dir u:" commands.

 This is easiest if you have serial port attached, or use
 [http://wiki.laptop.org/go/Firmware/Remote#Using_telnetd telnetd] with
 wireless] or with a supported USB ethernet.

Ticket URL: <http://dev.laptop.org/ticket/12158#comment:20>
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