#4606 NORM 9.1.0: XO can't resume from suspend at a particular time set by software

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#4606: XO can't resume from suspend at a particular time set by software
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     Reporter:  gnu          |        Owner:  rsmith                  
         Type:  enhancement  |       Status:  new                     
     Priority:  normal       |    Milestone:  9.1.0                   
    Component:  hardware     |      Version:  Mass Production Hardware
   Resolution:               |     Keywords:  power                   
  Next_action:  design       |   Spec_stage:  unknown                 
    Blockedby:  6053         |     Blocking:  8094                    
Spec_reviewer:               |     Verified:  0                       
Spec_reviewed:  0            |  
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Changes (by gnu):

 * cc: dsaxena (added)
  * spec_stage:  => unknown
  * spec_reviewed:  => 0
  * blockedby:  => 6053


Comment:

 #6053 also relates to accurate time and suspend (Linux slips up to a
 second from realtime whenever we suspend), and will need to be fixed to
 make timed suspends work.

 RTC wakeups with less than 60 seconds' delay should be easily possible
 without danger.  I think Wad was not thinking a literal "minute" when he
 wrote "unless at least a minute in the future".  As he says, the danger is
 if a wakeup occurs DURING a suspend -- we should be able to time our
 suspends to well within a second, and our wakeups to within two seconds or
 better.

 [As an addendum to Jordan's last comment:  An MFGPT cannot cause a wakeup
 directly.  But it can wiggle a GPIO pin.  Some of those pins, if not
 driven from outside, can be internally wired inside the Geode companion
 chip to cause a wakeup.  The XO is not wired that way (all of its GPIO
 pins are being driven for other things), but other Geode-based devices
 could be.]

-- 
Ticket URL: <http://dev.laptop.org/ticket/4606#comment:12>
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