#9692 HIGH Not Tri: XO-1.5 needs delay in powering off the internal SD card

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#9692: XO-1.5 needs delay in powering off the internal SD card
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 Reporter:  wad                  |                 Owner:  rsmith       
     Type:  enhancement          |                Status:  new          
 Priority:  high                 |             Milestone:  Not Triaged  
Component:  embedded controller  |               Version:  not specified
 Keywords:  sdmmc XO-1.5         |           Next_action:  design       
 Verified:  0                    |   Deployment_affected:               
Blockedby:                       |              Blocking:               
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 In order to avoid powering down an SD card while it is still writing data
 into the NAND Flash array, we shouldn't remove power from the SD card
 immediately after a write.

 I propose that instead, we maintain power to the SD card for N
 milliseconds after shutting down the system (or placing the system in S3
 --- suspend).   If the system resumes before SD power is cut, then power
 should remain.

 On B3 and later prototypes, the power control for the internal SD card is
 provided by the EC, not the southbridge, allowing easy implementation of
 this feature.   In addition, the internal SD card is powered from a 3.3V
 rail powered in suspend.

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Ticket URL: <http://dev.laptop.org/ticket/9692>
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