[Trac #42] Audio driver for AD1888 - sensor input mode

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#42: Audio driver for AD1888 - sensor input mode
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 Reporter:  jg       |        Owner:  dilinger
     Type:  task     |       Status:  new     
 Priority:  blocker  |    Milestone:  BTest-2 
Component:  kernel   |   Resolution:          
 Keywords:           |  
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Comment (by wmb at firmworks.com):

 The GPIO pin assignment has changed for B2, so we need to modify the code
 that configures the MIC input for AC or DC coupling.  The bypass switch
 used to be controlled by the EC, but as of B2 it is controlled by GPIO 01
 on the 5536.
 Therefore, it's no longer possible to use an EC command to switch it on
 and off.

 To put it in DC coupled mode you now have to write 0x0002 the GPIO_OUT_VAL
 register,
 and for AC coupled mode, you write 0x20000 to that same register.

 This, of course, needs to be dependent on the board type.  A-test and B1
 use the EC
 method, B2 uses the 5536 GPIO method.

-- 
Ticket URL: <http://dev.laptop.org/ticket/42#comment:13>
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