On Fri, Feb 28, 2014 at 05:04:25PM +0800, Xiubo Li wrote:

> "Just removing the set_cache_io() call will not work for all 
> drivers. There are some MFD child devices which use regmap from the parent 
> device. So dev_get_regmap() will return NULL for those."

This is the sort of thing that I was referring to when talking about
doing the non-boring drivers separately.  As well as the warnings Lars
mentioned there's a bisection issue here:

> -	codec->control_data = da7213->regmap;
> -	ret = snd_soc_codec_set_cache_io(codec, 8, 8, SND_SOC_REGMAP);
> -	if (ret < 0) {
> -		dev_err(codec->dev, "Failed to set cache I/O: %d\n", ret);
> -		return ret;
> -	}
> -
>  	/* Default to using ALC auto offset calibration mode. */
>  	snd_soc_update_bits(codec, DA7213_ALC_CTRL1,
>  			    DA7213_ALC_CALIB_MODE_MAN, 0);

Unless the core sets up the I/O before calling probe() the above is
going to mean that the snd_soc_update_bits() call fails since the I/O
operations won't have been set up.  There is a defualt call to set a
regmap up but it's only done after the probe.