[ALSA] Fix PCM write blocking

The snd_pcm_lib_write1() may block in some weird condition:
  - the stream isn't started
  - avail_min is big (e.g. period size)
  - partial write up to buffer_size - avail_min
The patch fixes this invalid blocking problem.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
This commit is contained in:
Takashi Iwai 2008-01-08 18:00:04 +01:00 committed by Jaroslav Kysela
parent 8ace4f3c9d
commit fa5717f209

View File

@ -1655,8 +1655,11 @@ static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
if (runtime->sleep_min == 0 && runtime->status->state == SNDRV_PCM_STATE_RUNNING)
snd_pcm_update_hw_ptr(substream);
avail = snd_pcm_playback_avail(runtime);
if (((avail < runtime->control->avail_min && size > avail) ||
(size >= runtime->xfer_align && avail < runtime->xfer_align))) {
if (!avail ||
(snd_pcm_running(substream) &&
((avail < runtime->control->avail_min && size > avail) ||
(size >= runtime->xfer_align &&
avail < runtime->xfer_align)))) {
wait_queue_t wait;
enum { READY, SIGNALED, ERROR, SUSPENDED, EXPIRED, DROPPED } state;
long tout;