ASoC: add control components management

This ASCII string can carry additional information about
soundcard components or configuration. Add the possibility
to set this string via the ASoC card.

Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Cc: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20191119174933.25526-1-perex@perex.cz
Signed-off-by: Mark Brown <broonie@kernel.org>

include/sound/soc.h

@@ -982,6 +982,7 @@ struct snd_soc_card {
 	const char *name;
 	const char *long_name;
 	const char *driver_name;
+	const char *components;
 	char dmi_longname[80];
 	char topology_shortname[32];
 

sound/soc/soc-core.c

@@ -2108,6 +2108,19 @@ static int snd_soc_bind_card(struct snd_soc_card *card)
 	soc_setup_card_name(card->snd_card->driver,
 			    card->driver_name, card->name, 1);
 
+	if (card->components) {
+		/* the current implementation of snd_component_add() accepts */
+		/* multiple components in the string separated by space, */
+		/* but the string collision (identical string) check might */
+		/* not work correctly */
+		ret = snd_component_add(card->snd_card, card->components);
+		if (ret < 0) {
+			dev_err(card->dev, "ASoC: %s snd_component_add() failed: %d\n",
+				card->name, ret);
+			goto probe_end;
+		}
+	}
+
 	if (card->late_probe) {
 		ret = card->late_probe(card);
 		if (ret < 0) {