#12580 NORM Future : XO-1.5 audio playback hang

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#12580: XO-1.5 audio playback hang
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           Reporter:  dsd        |       Owner:  dsd           
               Type:  defect     |      Status:  new           
           Priority:  normal     |   Milestone:  Future Release
          Component:  kernel     |     Version:  not specified 
         Resolution:             |    Keywords:                
        Next_action:  never set  |    Verified:  0             
Deployment_affected:             |   Blockedby:                
           Blocking:             |  
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Comment(by dsd):

 snd_pcm_wait() returns success ("you can write audio data now") but
 snd_pcm_writei fails with EAGAIN. So gstreamer gets confused.

 Disabling dmix doesn't help.

 We can catch this inside the kernel. With some logging messages added, in
 azx_interrupt() we can see that in the failure case, the system receives a
 flood of stream FIFO error interrupts (SD_STS 0x8), rather than the normal
 "audio buffer was played" interrupts (SD_STS 0x24).

 It's not clear why such a FIFO error occurred, nor what the FIFO actually
 is. And the HDA driver currently has no code to handle such conditions.

 http://mailman.alsa-project.org/pipermail/alsa-devel/2013-May/061990.html

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Ticket URL: <http://dev.laptop.org/ticket/12580#comment:2>
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