ASoC: Add I/O control bus information to factored out cache setup

While writes tend to be able to use a fairly bus independant format to
do the writes reads are all bus specific. To allow us to factor out
this code include the bus type as a parameter when setting up the
cache.

Initially just use this to factor out hw_write_t for I2C.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/codecs/wm8988.c b/sound/soc/codecs/wm8988.c
index 7d5b807..7486d3e 100644
--- a/sound/soc/codecs/wm8988.c
+++ b/sound/soc/codecs/wm8988.c
@@ -825,7 +825,8 @@
 };
 EXPORT_SYMBOL_GPL(soc_codec_dev_wm8988);
 
-static int wm8988_register(struct wm8988_priv *wm8988)
+static int wm8988_register(struct wm8988_priv *wm8988,
+			   enum snd_soc_control_type control)
 {
 	struct snd_soc_codec *codec = &wm8988->codec;
 	int ret;
@@ -854,7 +855,7 @@
 	memcpy(codec->reg_cache, wm8988_reg,
 	       sizeof(wm8988_reg));
 
-	ret = snd_soc_codec_set_cache_io(codec, 7, 9);
+	ret = snd_soc_codec_set_cache_io(codec, 7, 9, control);
 	if (ret < 0) {
 		dev_err(codec->dev, "Failed to set cache I/O: %d\n", ret);
 		goto err;
@@ -927,14 +928,13 @@
 		return -ENOMEM;
 
 	codec = &wm8988->codec;
-	codec->hw_write = (hw_write_t)i2c_master_send;
 
 	i2c_set_clientdata(i2c, wm8988);
 	codec->control_data = i2c;
 
 	codec->dev = &i2c->dev;
 
-	return wm8988_register(wm8988);
+	return wm8988_register(wm8988, SND_SOC_I2C);
 }
 
 static int wm8988_i2c_remove(struct i2c_client *client)
@@ -1019,7 +1019,7 @@
 
 	spi->dev.driver_data = wm8988;
 
-	return wm8988_register(wm8988);
+	return wm8988_register(wm8988, SND_SOC_SPI);
 }
 
 static int __devexit wm8988_spi_remove(struct spi_device *spi)