#11296 NORM 1.75-so: mmap to snd-mmp2-pcm fails

Zarro Boogs per Child bugtracker at laptop.org
Tue Oct 11 13:32:48 EDT 2011

#11296: mmap to snd-mmp2-pcm fails
           Reporter:  erikos    |       Owner:  saadia                           
               Type:  defect    |      Status:  new                              
           Priority:  normal    |   Milestone:  1.75-software                    
          Component:  kernel    |     Version:  Development build as of this date
         Resolution:            |    Keywords:                                   
        Next_action:  diagnose  |    Verified:  0                                
Deployment_affected:            |   Blockedby:                                   
           Blocking:            |  
Changes (by dsd):

 * cc: dsd (added)


 The patch is correct - Mitch cleared up our understanding. I'll commit it
 tomorrow with a better commit message, plus a fat comment explaining
 exactly whats going on here. In short, the audio DMA engine that we drive
 is simply for copying the data from the audio FIFO into audio SRAM, *not*
 for copying data into main memory. So the attempted use of the linux DMA
 API is incorrect here, since we aren't dealing with main memory.

Ticket URL: <http://dev.laptop.org/ticket/11296#comment:3>
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