#12179 NORM Future : Improve XO-4/8686 wireless power handling

Zarro Boogs per Child bugtracker at laptop.org
Fri Oct 12 17:23:40 EDT 2012

#12179: Improve XO-4/8686 wireless power handling
 Reporter:  dsd     |                 Owner:                
     Type:  defect  |                Status:  new           
 Priority:  normal  |             Milestone:  Future Release
Component:  kernel  |               Version:  not specified 
 Keywords:          |           Next_action:  never set     
 Verified:  0       |   Deployment_affected:                
Blockedby:          |              Blocking:                
 Setting the MMC_CAP_POWER_OFF_CARD flag on the host will result in power
 being removed to the wifi SDIO card when the network interface is brought
 down in Linux (the libertas driver has integration with runtime power

 This needs to be tested on XO-4. If it works reliably, we need to see
 about either quirking the kernel to auto-enable the flag for us, or maybe
 we will find a fix for the other platforms and be able to enable
 MMC_CAP_POWER_OFF_CARD by default for all platforms again (it was disabled
 due to problem with 8686).

 If it works, it would be nice to check with a scope that the card is
 really powered down. Maybe we could even unplug it and plug it in again at
 that point and check that the kernel "doesn't notice" and that the
 firmware behaviour (upload or not) is the same when re-powered in both

 See #12178 (XO-1.5) and #12177 (XO-1.75) for extra considerations.

Ticket URL: <http://dev.laptop.org/ticket/12179>
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