#1829 BLOC Trial-3: Control of VREF_OUT and HPF is coupled to Analog Input control

[Zarro Boogs per Child]

#1829: Control of VREF_OUT and HPF is coupled to Analog Input control
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  Reporter:  arjs     |       Owner:  dilinger
      Type:  defect   |      Status:  new     
  Priority:  blocker  |   Milestone:  Trial-3 
 Component:  kernel   |     Version:          
Resolution:           |    Keywords:  relnote 
  Verified:  0        |  
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Changes (by arjs):

 * cc: wmb at firmworks.com (added)

Comment:

 After our discussion on IRC and a little thinking --


 1. HPF control in Alsamixer: Making HPF exposed in Alsamixer to the user
 for changing doesn't make sense. It'd be best if we could eliminate it
 from Alsamixer and tie its functionality internally with Analog Input (one
 is muted when the other is unmuted and vice versa). One doesn't forsee any
 situation when the user would want to toggle HPF without toggling
 AnalogInput.


 2. Requirements regarding capture_open : VREF and AnalogInput must be set
 to default states when capture device is open. This is because anybody who
 writes a simple recording application, or just even uses arecord to do
 some basic recording shouldn't have to worry about these things.


 3. Requirements regarding capture_close: If an application enables VREF
 and doesn't disable it on quit, the LED will remain ON all the time. (the
 LED turns on whenever VREF is enabled). So on capture_close we need to
 disable VREF. We should also disable AnalogInput on capture_close.


 4. Name of VREF in Alsamixer: The name V_REFOUT doesn't make sense to a
 non-technical user. Thinking back a little, why would a user want to
 toggle this control at all ? IMHO in a case when he/she wants to simply
 say something into the mic/external-mic  and hear it in real time (not
 capture). So why not rename the control to something like MIC_ENABLE ?


 5. V_REFOUT (build561, B4) : When I go the Alsamixer control of V_REFOUT
 and unmute it, shouldn't the LED light up  ?(it doesn't) In some random
 instances, when I open the capture device and then close it (for example
 do a simple recording using arecord and then ctrl-c the recording
 process), and when I subsequently go to Alsamixer and toggle the VREF
 control, it seems to work (switches ON the LED when I unmute it).

-- 
Ticket URL: <https://dev.laptop.org/ticket/1829#comment:17>
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