From: Shengjiu Wang <shengjiu.wang@freescale.com>
Date: Fri, 12 Jun 2015 08:15:08 +0000 (+0800)
Subject: PCM: snd_pcm_xxxx_drain() maybe blocked after suspend and resume
X-Git-Tag: v1.1.0~67
X-Git-Url: https://git.alsa-project.org/?a=commitdiff_plain;h=9ee6ec80b80268932a372522ca192168e7812ccf;p=alsa-lib.git

PCM: snd_pcm_xxxx_drain() maybe blocked after suspend and resume

After suspend and resume, the alsa driver is stopped. But if alsa-lib run
into snd_pcm_xxxx_drain(), it need to wait avail >= pcm->stop_threshold,
otherwise, it will not exit the loop, so finally it is blocked at poll() of
snd_pcm_wait_nocheck(pcm, -1).
This patch is to add state check after snd_pcm_wait_nocheck(pcm, -1), if
the state is SND_PCM_STATE_SUSPENDED, then return error.

Signed-off-by: Shengjiu Wang <shengjiu.wang@freescale.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---

diff --git a/src/pcm/pcm_dmix.c b/src/pcm/pcm_dmix.c
index 4acbaf0e..58e4975d 100644
--- a/src/pcm/pcm_dmix.c
+++ b/src/pcm/pcm_dmix.c
@@ -617,6 +617,13 @@ static int snd_pcm_dmix_drain(snd_pcm_t *pcm)
 	snd_pcm_uframes_t stop_threshold;
 	int err;
 
+	switch (snd_pcm_state(dmix->spcm)) {
+	case SND_PCM_STATE_SUSPENDED:
+		return -ESTRPIPE;
+	default:
+		break;
+	}
+
 	if (dmix->state == SND_PCM_STATE_OPEN)
 		return -EBADFD;
 	if (pcm->mode & SND_PCM_NONBLOCK)
@@ -649,6 +656,13 @@ static int snd_pcm_dmix_drain(snd_pcm_t *pcm)
 			snd_pcm_dmix_sync_area(pcm);
 			snd_pcm_wait_nocheck(pcm, -1);
 			snd_pcm_direct_clear_timer_queue(dmix); /* force poll to wait */
+
+			switch (snd_pcm_state(dmix->spcm)) {
+			case SND_PCM_STATE_SUSPENDED:
+				return -ESTRPIPE;
+			default:
+				break;
+			}
 		}
 	} while (dmix->state == SND_PCM_STATE_DRAINING);
 	pcm->stop_threshold = stop_threshold;
diff --git a/src/pcm/pcm_dshare.c b/src/pcm/pcm_dshare.c
index b51758fb..02370dc7 100644
--- a/src/pcm/pcm_dshare.c
+++ b/src/pcm/pcm_dshare.c
@@ -368,6 +368,13 @@ static int snd_pcm_dshare_drain(snd_pcm_t *pcm)
 	snd_pcm_uframes_t stop_threshold;
 	int err;
 
+	switch (snd_pcm_state(dshare->spcm)) {
+	case SND_PCM_STATE_SUSPENDED:
+		return -ESTRPIPE;
+	default:
+		break;
+	}
+
 	if (dshare->state == SND_PCM_STATE_OPEN)
 		return -EBADFD;
 	if (pcm->mode & SND_PCM_NONBLOCK)
@@ -400,6 +407,13 @@ static int snd_pcm_dshare_drain(snd_pcm_t *pcm)
 			snd_pcm_dshare_sync_area(pcm);
 			snd_pcm_wait_nocheck(pcm, -1);
 			snd_pcm_direct_clear_timer_queue(dshare); /* force poll to wait */
+
+			switch (snd_pcm_state(dshare->spcm)) {
+			case SND_PCM_STATE_SUSPENDED:
+				return -ESTRPIPE;
+			default:
+				break;
+			}
 		}
 	} while (dshare->state == SND_PCM_STATE_DRAINING);
 	pcm->stop_threshold = stop_threshold;