#11867 BLOC 12.1.0: XO-1.5 - Occasional failure to wake from sleep using rtcwake

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#11867: XO-1.5 - Occasional failure to wake from sleep using rtcwake
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           Reporter:  Quozl     |       Owner:  pgf                              
               Type:  defect    |      Status:  new                              
           Priority:  blocker   |   Milestone:  12.1.0                           
          Component:  kernel    |     Version:  Development build as of this date
         Resolution:            |    Keywords:                                   
        Next_action:  diagnose  |    Verified:  0                                
Deployment_affected:            |   Blockedby:                                   
           Blocking:            |  
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Comment(by pgf):

 now that i have the EC wakeups working, things are still broken
 pretty often.  i'm using "aggressive" runin, which suspends for just
 10 seconds.  it frequently takes more than 10 seconds to get to the
 actual suspend, from the time i set the EC or rtc wakeup alarms.  i
 think this is because runin is, of course, stressing the machine a
 lot.

 since the EC wakeup doesn't interlock with a wakeup counter,
 i'm not surprised that it doesn't abort a pending suspend.  but an
 expired rtc alarm _should_ abort the next suspend, and i'm not seeing
 that.

 the following sequence aborts the suspend on 1.75, but does
 not on 1.5:
 {{{
    echo $(cat /sys/power/wakeup_count ) > /sys/power/wakeup_count
    rtcwake -s5 -m no ; sleep 7; echo mem > /sys/power/state
 }}}

 at /sys/class/rtc/rtc0/device/power/wakeup_count, it seems to only get
 incremented if the alarm goes off while we're actually suspended (or,
 perhaps, very close to suspended).  certainly "rtcwake -s5 -m no"
 doesn't bump it, and it needs to.

-- 
Ticket URL: <http://dev.laptop.org/ticket/11867#comment:20>
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