#9869 HIGH 1.5-sof: XO-1.5 screen glitches on resume

[Zarro Boogs per Child]

#9869: XO-1.5 screen glitches on resume
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           Reporter:  wad              |       Owner:  cjb                              
               Type:  defect           |      Status:  new                              
           Priority:  high             |   Milestone:  1.5-software-later               
          Component:  x window system  |     Version:  Development build as of this date
         Resolution:                   |    Keywords:  DCON XO-1.5                      
        Next_action:  code             |    Verified:  0                                
Deployment_affected:                   |   Blockedby:                                   
           Blocking:                   |  
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Comment(by pgf):

 i think the interrupts are missed because the dcon just isn't ready for
 another transition right away.  but that's just a guess.  yes, the proper
 fix would be to force a holdoff until the next request -- but at least for
 my loop, using synchronous freezes, the consequence of the missed
 interrupt is pretty benign -- the driver times out after waiting .5
 seconds, and the screen might glitch.  not worth worrying about.  the
 symptom you experienced, the lockup, is worse.  i still might call the
 risk tolerable.

 in any case, i'm seriously thinking we should be doing all of our freezes
 synchronously anyway, since in many cases we're freezing specifically to
 hide a screen update from the user (bootanim, ul-warning, and the powerd
 splash screens).  so we want to finish the freeze before we start writing.
 i think unfreezes can remain async without harm.

 there's still coordination of the vsync timings that wad opened this
 ticket with to be dealt with, as well.

-- 
Ticket URL: <http://dev.laptop.org/ticket/9869#comment:8>
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