From 4cdc115fd38b54642e8536a5c2389483bcb9b2e9 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Thu, 20 Aug 2009 16:40:16 +0200 Subject: ALSA: pcm - Fix drain behavior in non-blocking mode The current PCM core has the following problems regarding PCM draining in non-blocking mode: - the current f_flags isn't checked in snd_pcm_drain(), thus changing the mode dynamically via snd_pcm_nonblock() after open doesn't work. - calling drain in non-blocking mode just return -EAGAIN error, but doesn't provide any way to sync with draining. This patch fixes these issues. - check file->f_flags in snd_pcm_drain() properly - when O_NONBLOCK is set, PCM core sets the stream(s) to DRAIN state but quits ioctl immediately without waiting the whole drain; the caller can sync the drain manually via poll() Signed-off-by: Takashi Iwai --- sound/core/pcm_lib.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'sound/core/pcm_lib.c') diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 72cfd47af6b8..e3e78c7f2745 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -197,12 +197,16 @@ static int snd_pcm_update_hw_ptr_post(struct snd_pcm_substream *substream, avail = snd_pcm_capture_avail(runtime); if (avail > runtime->avail_max) runtime->avail_max = avail; - if (avail >= runtime->stop_threshold) { - if (substream->runtime->status->state == SNDRV_PCM_STATE_DRAINING) + if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) { + if (avail >= runtime->buffer_size) { snd_pcm_drain_done(substream); - else + return -EPIPE; + } + } else { + if (avail >= runtime->stop_threshold) { xrun(substream); - return -EPIPE; + return -EPIPE; + } } if (avail >= runtime->control->avail_min) wake_up(&runtime->sleep); -- cgit v1.2.3