#12707 NORM Not Tri: XO-4: EC sometimes mismanages stop mode

Zarro Boogs per Child bugtracker at laptop.org
Tue Jun 18 11:41:31 EDT 2013

#12707: XO-4: EC sometimes mismanages stop mode
 Reporter:  pgf                  |                 Owner:  pgf                               
     Type:  defect               |                Status:  new                               
 Priority:  normal               |             Milestone:  Not Triaged                       
Component:  embedded controller  |               Version:  Development source as of this date
 Keywords:                       |           Next_action:  diagnose                          
 Verified:  0                    |   Deployment_affected:                                    
Blockedby:                       |              Blocking:                                    
 normally when running on battery and in suspend, the EC will enter "stop
 mode", to reduce power consumption.  (it also does this when on battery
 only and laptop is powered off.)

 in order to flash the LED, the EC forces a watchdog every 4 seconds, which
 wakes it to do the flash.  it goes back to stop mode promptly.

 twice now i've caught it going into stop mode and _immediately_ coming
 back out.  4 seconds elapses, and it does it again.  so it's out of stop
 mode more than it's in stop mode.

 this may be a bug in the a secondary feature, which causes us to wake for
 a full 4 seconds once every 20 of the above loops.  (this is so that
 battery state bookkeeping can be performed once in a while.)

Ticket URL: <http://dev.laptop.org/ticket/12707>
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