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csete/gr-audio-alsa.diff

Created November 5, 2010 13:15
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Revisions

  1. csete revised this gist Dec 8, 2010. 1 changed file with 18 additions and 28 deletions.
    46 changes: 18 additions & 28 deletions gr-audio-alsa.diff
    View file
    Original file line number Diff line number Diff line change
    @@ -1,32 +1,22 @@
    diff --git a/gr-audio-alsa/src/audio_alsa_sink.cc b/gr-audio-alsa/src/audio_alsa_sink.cc
    index d6b7f84..4c8df3d 100644
    index d6b7f84..38ed86b 100644
    --- a/gr-audio-alsa/src/audio_alsa_sink.cc
    +++ b/gr-audio-alsa/src/audio_alsa_sink.cc
    @@ -35,6 +35,9 @@
    @@ -219,9 +219,15 @@ audio_alsa_sink::check_topology (int ninputs, int noutputs)
    int nchan = ninputs;
    int err;

    static bool CHATTY_DEBUG = false;

    +// flag to skip calling snd_pcm_hw_params when graph is reconfigured (c.f. FIXME)
    +static bool s_first_time = true;
    +

    static snd_pcm_format_t acceptable_formats[] = {
    // these are in our preferred order...
    @@ -234,10 +237,13 @@ audio_alsa_sink::check_topology (int ninputs, int noutputs)
    }

    // set the parameters into the driver...
    - err = snd_pcm_hw_params(d_pcm_handle, d_hw_params);
    - if (err < 0){
    - output_error_msg ("snd_pcm_hw_params failed", err);
    - return false;
    + if (s_first_time) {
    + err = snd_pcm_hw_params(d_pcm_handle, d_hw_params);
    + s_first_time = false;
    + if (err < 0){
    + output_error_msg ("snd_pcm_hw_params failed", err);
    + return false;
    + }
    }

    // get current s/w params
    - // FIXME check_topology may be called more than once.
    + // Check the state of the stream
    // Ensure that the pcm is in a state where we can still mess with the hw_params
    -
    + snd_pcm_state_t state;
    + state=snd_pcm_state(d_pcm_handle);
    + if ( state== SND_PCM_STATE_RUNNING)
    + return true; // If stream is running, don't change any parameters
    + else if(state == SND_PCM_STATE_XRUN )
    + snd_pcm_prepare ( d_pcm_handle ); // Prepare stream on underrun, and we can set parameters;
    +
    bool special_case = nchan == 1 && d_special_case_mono_to_stereo;
    if (special_case)
    nchan = 2;
  2. csete revised this gist Nov 5, 2010. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion gr-audio-alsa.diff
    View file
    Original file line number Diff line number Diff line change
    @@ -6,7 +6,7 @@ index d6b7f84..4c8df3d 100644

    static bool CHATTY_DEBUG = false;

    +// flag to skip calling snd_pcm_hw_params when graphs is reconfigured (c.f. FIXME)
    +// flag to skip calling snd_pcm_hw_params when graph is reconfigured (c.f. FIXME)
    +static bool s_first_time = true;
    +

  3. csete created this gist Nov 5, 2010.
    32 changes: 32 additions & 0 deletions gr-audio-alsa.diff
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,32 @@
    diff --git a/gr-audio-alsa/src/audio_alsa_sink.cc b/gr-audio-alsa/src/audio_alsa_sink.cc
    index d6b7f84..4c8df3d 100644
    --- a/gr-audio-alsa/src/audio_alsa_sink.cc
    +++ b/gr-audio-alsa/src/audio_alsa_sink.cc
    @@ -35,6 +35,9 @@

    static bool CHATTY_DEBUG = false;

    +// flag to skip calling snd_pcm_hw_params when graphs is reconfigured (c.f. FIXME)
    +static bool s_first_time = true;
    +

    static snd_pcm_format_t acceptable_formats[] = {
    // these are in our preferred order...
    @@ -234,10 +237,13 @@ audio_alsa_sink::check_topology (int ninputs, int noutputs)
    }

    // set the parameters into the driver...
    - err = snd_pcm_hw_params(d_pcm_handle, d_hw_params);
    - if (err < 0){
    - output_error_msg ("snd_pcm_hw_params failed", err);
    - return false;
    + if (s_first_time) {
    + err = snd_pcm_hw_params(d_pcm_handle, d_hw_params);
    + s_first_time = false;
    + if (err < 0){
    + output_error_msg ("snd_pcm_hw_params failed", err);
    + return false;
    + }
    }

    // get current s/w params