#4479 HIGH Update.: DCON corruption during suspend/resume

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#4479: DCON corruption during suspend/resume
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  Reporter:  wad     |       Owner:  dilinger
      Type:  defect  |      Status:  new     
  Priority:  high    |   Milestone:  Update.1
 Component:  kernel  |     Version:          
Resolution:          |    Keywords:  DCON    
  Verified:  0       |  
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Comment(by wad):

 But you SHOULD be reinitializing the DCON in the resume path, if we fail
 to communicate with it and power cycle it.

 We powered the chip down at line 131 cause it wouldn't talk to us, set
 is_powered_down to one in line 133, then jump back to the beginning of the
 dcon_bus_stabilize() function where we now power the chip back up --- but
 forget to re-initialize it.  Since nothing outside dcon_bus_stabilize()
 knows that we've power cycled the chip, nothing else will re-initialize
 its registers.

 No I didn't reinitialize all the registers by hand to test this.  It was
 too glaring a code error and Richard couldn't get i2cset or sdtools up and
 running on the affected laptop.

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Ticket URL: <http://dev.laptop.org/ticket/4479#comment:12>
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