[alsa-devel] [PATCH v2 0/2] ASoC: core: Ignoring pmdown_time for playback stream power down

Peter Ujfalusi peter.ujfalusi at ti.com
Fri Oct 14 13:43:32 CEST 2011

Hello Mark,

Changes since v1 (RFC):
- move the flag to per codec (snd_soc_codec)
- twl6040 to request to ignore the pmdown_time

Add support in core to ignore the pmdown_time when stopping the playback stream.
This will inline the DAPM stream stop event, so it is going to be executed
without delay at stream close time (for playback stream).

Backround: with the McPDM protocol we are sendning not only
the pure audio stream, but OMAP McPDM also transmits
additional information (for example offset cancellation).
If McPDM is stopped prior to the DAC this information will
be not sent to the codec, which can result noise rendered
by the twl6040 codec.

Peter Ujfalusi (2):
  ASoC: core: Add flag to ignore pmdown_time at pcm_close
  ASoC: twl6040: Request core to inline the DAPM sequence

 include/sound/soc.h        |    1 +
 sound/soc/codecs/twl6040.c |    1 +
 sound/soc/soc-pcm.c        |   15 +++++++++++----
 3 files changed, 13 insertions(+), 4 deletions(-)


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