#9423 NORM 1.5-F11: Stabilize OFW USB handling on XO-1.5

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#9423: Stabilize OFW USB handling on XO-1.5
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           Reporter:  wmb at firmworks.com    |       Owner:  wmb at firmworks.com
               Type:  defect               |      Status:  assigned         
           Priority:  normal               |   Milestone:  1.5-F11          
          Component:  ofw - open firmware  |     Version:  1.5-B2           
         Resolution:                       |    Keywords:                   
        Next_action:  test in release      |    Verified:  0                
Deployment_affected:                       |   Blockedby:                   
           Blocking:                       |  
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Changes (by wmb at firmworks.com):

  * next_action:  diagnose => test in release


Comment:

 The problem with mass storage devices seems to be specific to a particular
 Belkin DataTraveler 2 GB stick.  The symptom is that, every now and then,
 the first attempt to talk to the device (e.g. with "dir") fails.  It
 eventually times out (about 10 seconds), and then if you try again
 (without rebooting), it works.  I haven't seen this problem on any other
 sticks.

 Another problem occurs with D-Link DUB-E100 LAN interface.  That symptom
 is "Failed to set device address" during initial probing.  When it
 happens, you must hard-power-cycle -
 "bye" is not enough.

 I fixed that second problem with svn 1442.  It adds 2 seconds of extra
 "off" time for the USB power during OFW reboot (but not for resume from
 S3).  That gives the power rail time to discharge.  The 500 mS of "off"
 time that results from the EC's contribution to the reboot time is not
 enough - the USB power rail starts to droop but gets just low enough to
 confuse the LAN device some of the time.

 I'm going to ignore the USB stick problem for now, hoping that it is
 limited to this one stick.

-- 
Ticket URL: <http://dev.laptop.org/ticket/9423#comment:3>
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