#2765 BLOC 8.2.1: Need programmable delay to turn off DCON chip.

[Zarro Boogs per Child]

#2765: Need programmable delay to turn off DCON chip.
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   Reporter:  jg                   |       Owner:  cjb           
       Type:  defect               |      Status:  new           
   Priority:  blocker              |   Milestone:  8.2.1         
  Component:  power manager (OHM)  |     Version:                
 Resolution:                       |    Keywords:  power, relnote
Next_action:  never set            |    Verified:  0             
  Blockedby:                       |    Blocking:                
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Changes (by gnu):

 * cc: gnu (added)


Comment:

 Why do we need to delay turning off the DCON chip?  We now turn off the
 WiFi immediately when it's not needed, and re-power it as soon as it is
 needed.  I think we should try powering off the DCON chip anytime we're
 asking the DCON chip to power off the screen.  This would save a bunch of
 power, have no user-visible effect, and doesn't require any more complex
 timers.  What it does require is the ability to power-on and reinitialize
 the DCON when we next need it.

 (Only if powering the DCON back on requires some long, visible delay, will
 this cause any trouble for the end user.)

 PS:  Waking the CPU. having Ohm turn things on or off, then decide to shut
 down the CPU again, is simple.  We are already doing it, mostly when we
 have bugs in ohm that make it go right back to sleep after a wakeup.  Such
 as when it used to get confused about the state of the lid-closed switch.

-- 
Ticket URL: <http://dev.laptop.org/ticket/2765#comment:13>
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