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/sound/soc/codecs/wm8900.c b/sound/soc/codecs/wm8900.c
index dbc368c..19a6b25 100644
--- a/sound/soc/codecs/wm8900.c
+++ b/sound/soc/codecs/wm8900.c
@@ -744,7 +744,7 @@
 static int wm8900_set_fll(struct snd_soc_codec *codec,
 	int fll_id, unsigned int freq_in, unsigned int freq_out)
 {
-	struct wm8900_priv *wm8900 = codec->private_data;
+	struct wm8900_priv *wm8900 = snd_soc_codec_get_drvdata(codec);
 	struct _fll_div fll_div;
 	unsigned int reg;
 
@@ -1131,7 +1131,7 @@
 {
 	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
 	struct snd_soc_codec *codec = socdev->card->codec;
-	struct wm8900_priv *wm8900 = codec->private_data;
+	struct wm8900_priv *wm8900 = snd_soc_codec_get_drvdata(codec);
 	int fll_out = wm8900->fll_out;
 	int fll_in  = wm8900->fll_in;
 	int ret;
@@ -1155,7 +1155,7 @@
 {
 	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
 	struct snd_soc_codec *codec = socdev->card->codec;
-	struct wm8900_priv *wm8900 = codec->private_data;
+	struct wm8900_priv *wm8900 = snd_soc_codec_get_drvdata(codec);
 	u16 *cache;
 	int i, ret;
 
@@ -1205,7 +1205,7 @@
 		return -ENOMEM;
 
 	codec = &wm8900->codec;
-	codec->private_data = wm8900;
+	snd_soc_codec_set_drvdata(codec, wm8900);
 	codec->reg_cache = &wm8900->reg_cache[0];
 	codec->reg_cache_size = WM8900_MAXREG;
 
@@ -1304,7 +1304,7 @@
 	wm8900_set_bias_level(wm8900_codec, SND_SOC_BIAS_OFF);
 
 	wm8900_dai.dev = NULL;
-	kfree(wm8900_codec->private_data);
+	kfree(snd_soc_codec_get_drvdata(wm8900_codec));
 	wm8900_codec = NULL;
 
 	return 0;