#1961 NORM Trial-2: Battery indicator is inaccurate

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#1961: Battery indicator is inaccurate
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  Reporter:  jfuhrer        |       Owner:  hughsient at gmail.com
      Type:  defect         |      Status:  new                
  Priority:  normal         |   Milestone:  Trial-2            
 Component:  power manager  |     Version:                     
Resolution:                 |    Keywords:                     
  Verified:  0              |  
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Comment (by rsmith):

 Replying to [ticket:1961 jfuhrer]:

 > I've observed strange behavior with the battery charge indicator in the
 past couple builds. Sometimes, it does not decrease when unplugged or will
 not increase when charging. Occasionally, the charge will leap up by a
 large amount all at once. It generally corrects itself after a while.

 I've seen cases where the EC code is failing to reset the
 capacity,voltage, current, etc values to zero when the battery is removed.
 I'm also beginning to get some reports back from the users that the
 battery capacity report from the EC can be erratic.  The equations that
 govern the calculations for battery capacity on a NiMH battery are pretty
 complex.  So I can't really say I'm that surprised.

 It would be really helpful to me if you could set up some sort of
 userspace logging facility that can track the battery management system
 parameters.  There is a lot of info in the battery EEPROM beyond the
 voltage and current.

 With a newer kernel and EC code you can:
 - Read a unique 64-bit ID for the battery pack
 - Read all the values in the gas guage EEPROM using the OLPC battery
 driver.

 With these features we can track BMS parameters on a per battery basis.
 This will be crucial to diagnose some of the more bizarre battery
 problems.  One the HAL stuff settles down please contact me (richard at
 laptop dot org) and I'll help you get a list of EEPROM values that are
 important to track.

 Having all that data logged across multiple charge/discharge cycles will
 be _really_ useful for solving the battery corner cases that I think are
 beginning to surface.

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Ticket URL: <http://dev.laptop.org/ticket/1961#comment:2>
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