#10287 NORM Not Tri: EC must be careful to prevent leakage through control lines when powered off

[Zarro Boogs per Child]

#10287: EC must be careful to prevent leakage through control lines when powered
off
---------------------------------+------------------------------------------
 Reporter:  wad                  |                 Owner:  rsmith       
     Type:  specification        |                Status:  new          
 Priority:  normal               |             Milestone:  Not Triaged  
Component:  embedded controller  |               Version:  not specified
 Keywords:  XO-1.75              |           Next_action:  code         
 Verified:  0                    |   Deployment_affected:               
Blockedby:                       |              Blocking:               
---------------------------------+------------------------------------------
 In XO-1.75, the EC provides a number of control signals for switching
 different subsections on and off.   Some number of these signals are
 active low.

 If these active low power control signals are held high when the main SOC
 is completely powered off, they will cause leakage onto turned-off power
 rails.

 This ticket is a reminder that the EC firmware should only deassert those
 active low power switching signals high immediately before powering on the
 main power supplies, and should make sure that they are asserted (low)
 after turning off the main power supplies.

-- 
Ticket URL: <http://dev.laptop.org/ticket/10287>
One Laptop Per Child <http://laptop.org/>
OLPC bug tracking system