cvs commit: src/sys/dev/sound/pci ich.c

[Ariff Abdullah]

ariff       2005-11-14 18:18:12 UTC

  FreeBSD src repository

  Modified files:
    sys/dev/sound/pci    ich.c 
  Log:
  - Added few more Intel HDA ids (ICH 6/7) which does have backward
    compatible AC97 codec.
  - As the driver supports so many variants, create a table ids for
    ease of probing and maintenance.
    Submitted by:         yongari
    Reviewed/Tested by:   multimedia@
  - From luigi:
          The code to compute fragment sizes in the ich driver almost
          invariably ends up using the full buffer available, no matter
          how the user specifies fragment size and number.
          With audio telephony (8khz, 16bit-stereo) and the 16k buffer
          size this results in an unbearable 500ms delay.
          This patch makes sure that we never use more than 4 fragments,
          (i don't think we need more unless there are huge interrupt
          servicing latencies), and obey to the requested fragment size,
          so that latency is acceptable.
    Based on this (and after much regression tests), I can conclude
    that this driver works best with 2 fragments, thus solving various
    long standing issues of ICH driver not capable to flush or play
    short files perfectly.
    Suggested by:         luigi (the idea of smaller fragments)
  - MPSAFE conversion.
  
  Approved by:    netchild (mentor)
  
  Revision  Changes    Path
  1.55      +153 -103  src/sys/dev/sound/pci/ich.c