ASoC: Move active copy of CODEC read and write into runtime structure

We shouldn't be assigning to the driver structure (which really ought
to be const, further patch to follow) though there's unlikely to be any
actual problem except in the unlikely case that two devices with the
same driver but different bus types appear in the same system.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>

include/sound/soc.h

@@ -476,6 +476,8 @@ struct snd_soc_codec {
 	void *control_data; /* codec control (i2c/3wire) data */
 	hw_write_t hw_write;
 	unsigned int (*hw_read)(struct snd_soc_codec *, unsigned int);
+	unsigned int (*read)(struct snd_soc_codec *, unsigned int);
+	int (*write)(struct snd_soc_codec *, unsigned int, unsigned int);
 	void *reg_cache;
 	const struct snd_soc_cache_ops *cache_ops;
 	struct mutex cache_rw_mutex;

sound/soc/soc-cache.c

@@ -728,8 +728,8 @@ int snd_soc_codec_set_cache_io(struct snd_soc_codec *codec,
 		return -EINVAL;
 	}
 
-	codec->driver->write = io_types[i].write;
-	codec->driver->read = io_types[i].read;
+	codec->write = io_types[i].write;
+	codec->read = io_types[i].read;
 
 	switch (control) {
 	case SND_SOC_CUSTOM:

sound/soc/soc-core.c

@@ -2077,7 +2077,7 @@ unsigned int snd_soc_read(struct snd_soc_codec *codec, unsigned int reg)
 {
 	unsigned int ret;
 
-	ret = codec->driver->read(codec, reg);
+	ret = codec->read(codec, reg);
 	dev_dbg(codec->dev, "read %x => %x\n", reg, ret);
 	trace_snd_soc_reg_read(codec, reg, ret);
 
@@ -2090,7 +2090,7 @@ unsigned int snd_soc_write(struct snd_soc_codec *codec,
 {
 	dev_dbg(codec->dev, "write %x = %x\n", reg, val);
 	trace_snd_soc_reg_write(codec, reg, val);
-	return codec->driver->write(codec, reg, val);
+	return codec->write(codec, reg, val);
 }
 EXPORT_SYMBOL_GPL(snd_soc_write);
 
@@ -3448,6 +3448,8 @@ int snd_soc_register_codec(struct device *dev,
 
 	INIT_LIST_HEAD(&codec->dapm.widgets);
 	INIT_LIST_HEAD(&codec->dapm.paths);
+	codec->write = codec_drv->write;
+	codec->read = codec_drv->read;
 	codec->dapm.bias_level = SND_SOC_BIAS_OFF;
 	codec->dapm.dev = dev;
 	codec->dapm.codec = codec;