rate plugin: wait for data to be drained

When draining, wait for the slave device to become ready to prevent
committing more data than would have been available in the buffer.

diff --git a/src/pcm/pcm_rate.c b/src/pcm/pcm_rate.c
index 414edab64e8d3fd16fe9a678d96d5ca918086448..083819b890b6a8a7b223e82eafb131924e90ae55 100644 (file)
--- a/src/pcm/pcm_rate.c
+++ b/src/pcm/pcm_rate.c
@@ -1297,11 +1297,22 @@ static int snd_pcm_rate_drain(snd_pcm_t *pcm)
 
        if (pcm->stream == SND_PCM_STREAM_PLAYBACK) {
                /* commit the remaining fraction (if any) */
-               snd_pcm_uframes_t size, ofs;
+               snd_pcm_uframes_t size, ofs, saved_avail_min;
+               snd_pcm_sw_params_t sw_params;
+
+               /* temporarily set avail_min to one period */
+               sw_params = rate->sw_params;
+               saved_avail_min = sw_params.avail_min;
+               sw_params.avail_min = rate->gen.slave->period_size;
+               snd_pcm_sw_params(rate->gen.slave, &sw_params);
+
                size = rate->appl_ptr - rate->last_commit_ptr;
                ofs = rate->last_commit_ptr % pcm->buffer_size;
                while (size > 0) {
                        snd_pcm_uframes_t psize, spsize;
+
+                       if (snd_pcm_wait(rate->gen.slave, -1) < 0)
+                               break;
                        if (size > pcm->period_size) {
                                psize = pcm->period_size;
                                spsize = rate->gen.slave->period_size;
@@ -1316,6 +1327,8 @@ static int snd_pcm_rate_drain(snd_pcm_t *pcm)
                        ofs = (ofs + psize) % pcm->buffer_size;
                        size -= psize;
                }
+               sw_params.avail_min = saved_avail_min;
+               snd_pcm_sw_params(rate->gen.slave, &sw_params);
        }
        return snd_pcm_drain(rate->gen.slave);
 }