A quick grep reveals:
mc13783.c: codec->control_data = dev_get_regmap(codec->dev->parent, NULL);
si476x.c: codec->control_data = dev_get_regmap(codec->dev->parent, NULL);
wm5102.c: codec->control_data = priv->core.arizona->regmap;
wm5110.c: codec->control_data = priv->core.arizona->regmap;
wm8997.c: codec->control_data = priv->core.arizona->regmap;
But there might be more.
I have found the following ones, who are using MFD & set_cache_io.
1 143 sound/soc/codecs/cq93vc.c <<cq93vc_probe>>
snd_soc_codec_set_cache_io(codec, 32, 32, SND_SOC_REGMAP);
2 618 sound/soc/codecs/mc13783.c <<mc13783_probe>>
ret = snd_soc_codec_set_cache_io(codec, 8, 24, SND_SOC_REGMAP);
3 1765 sound/soc/codecs/wm5102.c <<wm5102_codec_probe>>
ret = snd_soc_codec_set_cache_io(codec, 32, 16, SND_SOC_REGMAP);
4 1593 sound/soc/codecs/wm5110.c <<wm5110_codec_probe>>
ret = snd_soc_codec_set_cache_io(codec, 32, 16, SND_SOC_REGMAP);
5 1510 sound/soc/codecs/wm8350.c <<wm8350_codec_probe>>
snd_soc_codec_set_cache_io(codec, 8, 16, SND_SOC_REGMAP);
6 1322 sound/soc/codecs/wm8400.c <<wm8400_codec_probe>>
snd_soc_codec_set_cache_io(codec, 8, 16, SND_SOC_REGMAP);
7 4004 sound/soc/codecs/wm8994.c <<wm8994_codec_probe>>
snd_soc_codec_set_cache_io(codec, 16, 16, SND_SOC_REGMAP);
8 1058 sound/soc/codecs/wm8997.c <<wm8997_codec_probe>>
ret = snd_soc_codec_set_cache_io(codec, 32, 16, SND_SOC_REGMAP);