ASoC: core: Fix check before defaulting to regmap

Check if the chip has provided a write operation (which is mandatory for
I/O) rather than looking for control data as some of the MFDs use a global
for this. Also skip the attempt if there's no regmap available by device
in case things get confused by the attempt to default.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Tested-by: NPeter Ujfalusi <peter.ujfalusi@ti.com>

sound/soc/soc-core.c

@@ -1096,7 +1096,7 @@ static int soc_probe_codec(struct snd_soc_card *card,
 	}
 
 	/* If the driver didn't set I/O up try regmap */
-	if (!codec->control_data)
+	if (!codec->write && dev_get_regmap(codec->dev, NULL))
 		snd_soc_codec_set_cache_io(codec, 0, 0, SND_SOC_REGMAP);
 
 	if (driver->controls)