File 0006-pcm-dmix-Fix-doubly-resume-of-slave-PCM.patch of Package alsa

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File 0006-pcm-dmix-Fix-doubly-resume-of-slave-PCM.patch of Package alsa (Revision e11bd280102f253778219b7734583edd)

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From 5610b356b5f110f7f8e586f56e5b74e0f0c2db38 Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@suse.de>
Date: Wed, 11 May 2016 13:06:25 +0200
Subject: [PATCH] pcm: dmix: Fix doubly resume of slave PCM

The dmix plugin and co may trigger the resume for each instance in
snd_pcm_direct_resume().  It means that the slave PCM gets resumed or
re-prepared/started by each opened dmix stream, and this may end up
with the doubly triggers even though the slave PCM has been already
resumed by another dmix stream.

For avoiding this conflicts, check the slave PCM state and resume only
when it's still in the suspended state.  Meanwhile we keep the shadow
state updated no matter whether the slave was triggered or not.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 src/pcm/pcm_direct.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/pcm/pcm_direct.c b/src/pcm/pcm_direct.c
index e28738b0de96..ac082f1a73b2 100644
--- a/src/pcm/pcm_direct.c
+++ b/src/pcm/pcm_direct.c
@@ -841,6 +841,12 @@ int snd_pcm_direct_resume(snd_pcm_t *pcm)
 	int err;
 	
 	snd_pcm_direct_semaphore_down(dmix, DIRECT_IPC_SEM_CLIENT);
+	/* resume only when the slave PCM is still in suspended state */
+	if (snd_pcm_state(dmix->spcm) != SND_PCM_STATE_SUSPENDED) {
+		err = 0;
+		goto out;
+	}
+
 	err = snd_pcm_resume(dmix->spcm);
 	if (err == -ENOSYS) {
 		/* FIXME: error handling? */
@@ -848,6 +854,7 @@ int snd_pcm_direct_resume(snd_pcm_t *pcm)
 		snd_pcm_start(dmix->spcm);
 		err = 0;
 	}
+ out:
 	dmix->state = snd_pcm_state(dmix->spcm);
 	snd_pcm_direct_semaphore_up(dmix, DIRECT_IPC_SEM_CLIENT);
 	return err;
-- 
2.8.2

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File 0006-pcm-dmix-Fix-doubly-resume-of-slave-PCM.patch of Package alsa (Revision e11bd280102f253778219b7734583edd)

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