[Trac #841] reproducible loss of wireless association

[Zarro Boogs per Child]

#841: reproducible loss of wireless association
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 Reporter:  Quozl     |        Owner:  marcelo 
     Type:  defect    |       Status:  assigned
 Priority:  blocker   |    Milestone:  BTest-3 
Component:  wireless  |   Resolution:          
 Keywords:            |  
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Comment (by dcbw):

 This should also be reproducible by doing a manual connection and running
 'iwlist eth0 scan' every so often.

 Scanning should _not_ cause the firmware or driver to loose the
 association to the AP ever.  We should probably make sure that userspace-
 triggered scanning is async, so that each scan request actually triggers 3
 or 4 firmware scan commands.  They are already broken up like that in the
 driver, but the driver blocks on completion of all 3 before returning.
 The trick is to make sure you don't stay off the currently associated AP's
 channel for too long; so after scanning each channel or two (using ~ 200 -
 250ms dwell time), jump back to the association channel for a bit, then
 scan two more channels, etc.

 We should put some debugging code into the driver to see exactly how long
 a scan really takes, and how long the card is on a different channel than
 the current association channel.  Another option is to have the card tell
 the AP to queue packets and such when it scans, which is similar to the
 notification cards send when they enter brief sleep for power saving.

-- 
Ticket URL: <http://dev.laptop.org/ticket/841#comment:19>
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