#11980 HIGH Not Tri: XO-1 no longer maintains external SD card access over suspend/resume (was: Presence of swap brakes the system after wakeup)

[Zarro Boogs per Child]

#11980: XO-1 no longer maintains external SD card access over suspend/resume
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           Reporter:  mavrothal  |       Owner:                                   
               Type:  defect     |      Status:  new                              
           Priority:  high       |   Milestone:  Not Triaged                      
          Component:  kernel     |     Version:  Development build as of this date
         Resolution:             |    Keywords:  powerd                           
        Next_action:  diagnose   |    Verified:  0                                
Deployment_affected:             |   Blockedby:                                   
           Blocking:             |  
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Comment(by dsd):

 Thanks for the reminder here.

 The problem is that the XO-1 is now losing the card during suspend/resume,
 as if it has been removed and reinserted. Previously, the card presence
 (and anything open/in use) was maintained over suspend.

 With help from Chris Ball we identified that sdhci_request, called during
 resume, checks SDHCI_PRESENT_STATE. During early resume, this register
 says that the card is not present. About 400ms after sdhci_resume_host
 returns, the hardware generates an interrupt saying "card inserted" and
 then starts acknowledging card presence again.

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Ticket URL: <http://dev.laptop.org/ticket/11980#comment:1>
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