[alsa-devel] [PATCH 0/1] ASoC: TWL4030: Constraint setting rework

Peter Ujfalusi peter.ujfalusi at nokia.com
Fri Apr 17 14:55:07 CEST 2009


The current implementation of constraints in TWL4030 codec needs some tuning.

An interesting case can be generated by using gstreamer:
gst-launch-0.10 alsasrc device=hw:0 ! alsasink device=hw:0 sync=false

What would (since the current implementation blocks it) happen in this case is:
playback stream: open
capture stream: open
capture stream: hw_params
playback_stream: hw_params

In capture open we set the constraints to the capture stream based on the
playback streams runtime parameters, and they are 0 (rate = 0, sample_bits = 0),
since the hw_param has not been called for that stream yet...

The following patch fixes this issue among other possible scenarios regarding to
constraint handling.

Note that I'm not using the just introduced symmetric_rates feature of ASoC
introduced by Mark Brown recently, since I think that also suffers from this
problem (or not, I have to try it out first to be sure about it)

Peter Ujfalusi (1):
  ASoC: TWL4030: Fix for the constraint handling

 sound/soc/codecs/twl4030.c |   85 ++++++++++++++++++++++++++++++++++----------
 1 files changed, 66 insertions(+), 19 deletions(-)

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