ASoC: Add indirection for CODEC private data

One of the features of the multi CODEC work is that it embeds a struct
device in the CODEC to provide diagnostics via a sysfs class rather than
via the device tree, at which point it's much better to use the struct
device private data rather than having two places to store it. Provide
an accessor function to allow this change to be made more easily, and
update all the CODEC drivers are updated.

To ensure use of the accessor the private data structure member is
renamed, meaning that if code developed with older an older core that
still uses private_data is merged it will fail to build.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
diff --git a/include/sound/soc.h b/include/sound/soc.h
index 4ab3dad..01e9c66 100644
--- a/include/sound/soc.h
+++ b/include/sound/soc.h
@@ -414,7 +414,7 @@
 	struct snd_ac97 *ac97;  /* for ad-hoc ac97 devices */
 	unsigned int active;
 	unsigned int pcm_devs;
-	void *private_data;
+	void *drvdata;
 
 	/* codec IO */
 	void *control_data; /* codec control (i2c/3wire) data */
@@ -597,6 +597,17 @@
 	return codec->write(codec, reg, val);
 }
 
+static inline void snd_soc_codec_set_drvdata(struct snd_soc_codec *codec,
+					     void *data)
+{
+	codec->drvdata = data;
+}
+
+static inline void *snd_soc_codec_get_drvdata(struct snd_soc_codec *codec)
+{
+	return codec->drvdata;
+}
+
 #include <sound/soc-dai.h>
 
 #endif