#9983 HIGH 1.5-sof: Battery charging has race if EXT power bounces quickly

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#9983: Battery charging has race if EXT power bounces quickly
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           Reporter:  rsmith               |       Owner:  rsmith            
               Type:  defect               |      Status:  new               
           Priority:  high                 |   Milestone:  1.5-software-later
          Component:  embedded controller  |     Version:  not specified     
         Resolution:                       |    Keywords:                    
        Next_action:  code                 |    Verified:  0                 
Deployment_affected:                       |   Blockedby:                    
           Blocking:                       |  
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Comment(by rsmith):

 After further testing I've identified that the race can still be
 triggered.

 If you time the EXT power resume to coincide with the end of the AC loss
 debounce period then you trigger the race.

 You can duplicate this by unplugging the power a few times while watching
 the LED to get the timing and then anticipate when the LED will go out.
 Re-insert power at that instant and you trigger the race.

 I've also verified that the EC charge LED correctly matches the state when
 this happens now that its bound to the IO.  So it won't charge but the LED
 is not incorrectly lit.

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Ticket URL: <http://dev.laptop.org/ticket/9983#comment:1>
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