1. 03 8月, 2012 1 次提交
  2. 31 7月, 2012 1 次提交
  3. 05 7月, 2012 1 次提交
  4. 18 6月, 2012 1 次提交
  5. 12 6月, 2012 2 次提交
  6. 23 5月, 2012 1 次提交
  7. 21 5月, 2012 1 次提交
  8. 12 5月, 2012 1 次提交
    • T
      ALSA: pcm - Optimize the call of snd_pcm_update_hw_ptr() in read/write loop · 0910c216
      Takashi Iwai 提交于
      In the PCM read/write loop, the driver calls snd_pcm_update_hw_ptr()
      at each time at the beginning of the loop.  Russell King reported that
      this hogs CPU significantly.
      
      The current code assumes that the pointer callback is very fast and
      cheap, also not too much fine grained.  It's not true in all cases.
      When the pointer advances short samples while the read/write copy has
      been performed, the driver updates the hw_ptr and gets avail > 0
      again.  Then it tries to read/write these small chunks.  This repeats
      until the avail really gets to zero.
      
      For avoiding this situation, a simple workaround is to call
      snd_pcm_update_hw_ptr() only once at starting the loop, assuming that
      the read/write copy is performed fast enough.  If the available count
      becomes short, it goes to snd_pcm_wait_avail() anyway, and this
      processes right.
      Tested-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      Signed-off-by: NTakashi Iwai <tiwai@suse.de>
      0910c216
  9. 08 5月, 2012 2 次提交
  10. 18 4月, 2012 1 次提交
  11. 31 3月, 2012 1 次提交
  12. 15 3月, 2012 2 次提交
  13. 13 3月, 2012 1 次提交
  14. 12 3月, 2012 2 次提交
  15. 10 3月, 2012 1 次提交
  16. 28 2月, 2012 1 次提交
  17. 20 2月, 2012 1 次提交
  18. 09 2月, 2012 1 次提交
    • L
      ALSA: PCM - Add PCM creation API for internal PCMs. · 945e5038
      Liam Girdwood 提交于
      The new ASoC dynamic PCM core needs to create PCMs and substreams that are
      for use by internal ASoC drivers only and not visible to userspace for
      direct IO. These new PCMs are similar to regular PCMs expect they have no
      device nodes or procfs entries. The ASoC component drivers use them in exactly
      the same way as regular PCMs for PCM and DAI operations.
      
      The intention is that a dynamic PCM based driver will register both regular
      PCMs and internal PCMs. The regular PCMs will be used for all IO with userspace
      however the internal PCMs will be used by the driver to route digital audio
      through numerous back end DAI links (with potentially a DSP providing different
      hw_params, DAI formats based on the regular front end PCM params) to devices
      like CODECs, MODEMs, Bluetooth, FM, DMICs, etc
      
      This patch adds a new snd_pcm_new_internal() API call to create the internal PCM
      without device nodes or procfs. It also adds adds a new internal flag to snd_pcm.
      
      [fixed minor coding-style issues by tiwai]
      Signed-off-by: NLiam Girdwood <lrg@ti.com>
      Signed-off-by: NTakashi Iwai <tiwai@suse.de>
      945e5038
  19. 24 1月, 2012 1 次提交
  20. 13 1月, 2012 1 次提交
  21. 23 12月, 2011 3 次提交
  22. 19 12月, 2011 1 次提交
  23. 16 11月, 2011 2 次提交
  24. 14 11月, 2011 1 次提交
  25. 10 11月, 2011 1 次提交
  26. 06 11月, 2011 1 次提交
  27. 01 11月, 2011 4 次提交
  28. 31 10月, 2011 1 次提交
  29. 10 10月, 2011 1 次提交
  30. 09 10月, 2011 1 次提交