In __snd_pcm_lib_xfer(), when capture, if state is PREPARED and size is less than start_threshold nothing can be done. As there is no error, 0 is returned.
Signed-off-by: Ricardo Biehl Pasquali pasqualirb@gmail.com ---
version 2: The code was not changed. Just resubmitting to follow the rules from Documentation/process/submitting-patches.rst.
--- pcm_lib.c.orig 2018-08-21 15:31:54.457405053 -0300 +++ pcm_lib.c 2018-08-21 15:56:01.264549084 -0300 @@ -2125,7 +2125,7 @@ snd_pcm_sframes_t __snd_pcm_lib_xfer(str pcm_transfer_f transfer; bool nonblock; bool is_playback; - int err; + int err = 0;
err = pcm_sanity_check(substream); if (err < 0) @@ -2173,11 +2173,15 @@ snd_pcm_sframes_t __snd_pcm_lib_xfer(str goto _end_unlock;
if (!is_playback && - runtime->status->state == SNDRV_PCM_STATE_PREPARED && - size >= runtime->start_threshold) { - err = snd_pcm_start(substream); - if (err < 0) + runtime->status->state == SNDRV_PCM_STATE_PREPARED) { + if (size >= runtime->start_threshold) { + err = snd_pcm_start(substream); + if (err < 0) + goto _end_unlock; + } else { + /* nothing to do */ goto _end_unlock; + } }
runtime->twake = runtime->control->avail_min ? : 1;