#10882 NORM 1.75-so: OFW accelerometer driver fails on some XO-1.75 units

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#10882: OFW accelerometer driver fails on some XO-1.75 units
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           Reporter:  wmb at firmworks.com  |       Owner:  wad          
               Type:  defect             |      Status:  new          
           Priority:  normal             |   Milestone:  1.75-software
          Component:  hardware           |     Version:  1.75-A2      
         Resolution:                     |    Keywords:               
        Next_action:  test in release    |    Verified:  0            
Deployment_affected:                     |   Blockedby:               
           Blocking:                     |  
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Changes (by wad):

  * next_action:  diagnose => test in release


Comment:

 This is definitely the same issue as #11041.  This ticket is being closed
 for now, and the problem will be tracked there.

 We need to ensure that the I2C bus for the accelerometer runs at around 25
 KHz on A3/B1 motherboards.  We will fix the hardware to allow full speed
 operation starting with C1.

 The value written to the LSR field of the TWSI_LCR register on the I2C bus
 talking to the accelerometer should be 0X1FF, not the default 0x7E.  This
 has already been fixed in OFW, starting with Q4B05.

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Ticket URL: <http://dev.laptop.org/ticket/10882#comment:7>
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