patches.kzm9g/0079-ASoC-Hold-runtime-PM-references-to-components-of-act.patch

From a34733d7e91c1defeb73b851cb78e76db67a5e48 Mon Sep 17 00:00:00 2001
From: Mark Brown <broonie@opensource.wolfsonmicro.com>
Date: Sat, 3 Dec 2011 20:14:31 +0000
Subject: ASoC: Hold runtime PM references to components of active DAIs

Every device that implements runtime power management for DAIs is doing
it in pretty much the same way: in the startup callback they take a
runtime PM reference and then in the shutdown callback they release that
reference, keeping the device active while the DAI is active. Given the
frequency with which this is done and the obviousness of the need to keep
the device active in this period factor the code out into the core, taking
references on the device for each CPU DAI, CODEC DAI and DMA device in the
core.

As runtime PM is reference counted this shouldn't interfere with any
other reference holding by the drivers, and since (in common with the
existing implementations) we don't check for errors on enabling it
shouldn't matter if the device actually has runtime PM enabled or not.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
(cherry picked from commit d6652ef8229e9953543f41d8e081c23e653f0044)

Signed-off-by: Simon Horman <horms@verge.net.au>
---
 sound/soc/soc-pcm.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c
index f4864b0..3047db8 100644
--- a/sound/soc/soc-pcm.c
+++ b/sound/soc/soc-pcm.c
@@ -19,6 +19,7 @@
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/delay.h>
+#include <linux/pm_runtime.h>
 #include <linux/slab.h>
 #include <linux/workqueue.h>
 #include <sound/core.h>
@@ -81,6 +82,10 @@ static int soc_pcm_open(struct snd_pcm_substream *substream)
 	struct snd_soc_dai_driver *codec_dai_drv = codec_dai->driver;
 	int ret = 0;
 
+	pm_runtime_get_sync(cpu_dai->dev);
+	pm_runtime_get_sync(codec_dai->dev);
+	pm_runtime_get_sync(platform->dev);
+
 	mutex_lock_nested(&rtd->pcm_mutex, rtd->pcm_subclass);
 
 	/* startup the audio subsystem */
@@ -231,6 +236,11 @@ platform_err:
 		cpu_dai->driver->ops->shutdown(substream, cpu_dai);
 out:
 	mutex_unlock(&rtd->pcm_mutex);
+
+	pm_runtime_put(platform->dev);
+	pm_runtime_put(codec_dai->dev);
+	pm_runtime_put(cpu_dai->dev);
+
 	return ret;
 }
 
@@ -322,6 +332,11 @@ static int soc_codec_close(struct snd_pcm_substream *substream)
 	}
 
 	mutex_unlock(&rtd->pcm_mutex);
+
+	pm_runtime_put(platform->dev);
+	pm_runtime_put(codec_dai->dev);
+	pm_runtime_put(cpu_dai->dev);
+
 	return 0;
 }
 
-- 
1.7.10.2.565.gbd578b5