[PATCH] ASoC: core: Add name prefix for machines with different topologies

[Liam Girdwood <liam.r.girdwood@linux.intel.com>]

Provide a mechanism for drivers to modify there card name with a prefix
so that userspace can load a different configuration file to default.
This can be useful when topology has changed the PCMs and kcontrols
for a machine.

This will be used by SOF to differentiate sound card names for UCM etc.

Signed-off-by: Liam Girdwood <liam.r.girdwood@linux.intel.com>
---
 include/sound/soc.h  | 2 ++
 sound/soc/soc-core.c | 8 ++++++++
 2 files changed, 10 insertions(+)

diff --git a/include/sound/soc.h b/include/sound/soc.h
index 4e368c308f93..99b77feab364 100644
--- a/include/sound/soc.h
+++ b/include/sound/soc.h
@@ -1015,6 +1015,7 @@ struct snd_soc_platform_driver {
 
 	/* this platform uses topology and ignore machine driver FEs */
 	const char *ignore_machine;
+	const char *topology_name_prefix;
 	int (*be_hw_params_fixup)(struct snd_soc_pcm_runtime *rtd,
 				  struct snd_pcm_hw_params *params);
 	bool use_dai_pcm_id;	/* use the DAI link PCM ID as PCM device number */
@@ -1167,6 +1168,7 @@ struct snd_soc_card {
 	const char *long_name;
 	const char *driver_name;
 	char dmi_longname[80];
+	char topology_shortname[32];
 
 	struct device *dev;
 	struct snd_card *snd_card;
diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index 33840e5bc24e..4ab2b4ac8522 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -2144,6 +2144,14 @@ static void soc_check_tplg_fes(struct snd_soc_card *card)
 			if (!dai_link->stream_name)
 				dai_link->stream_name = dai_link->name;
 		}
+
+		/* Inform userspace we are using alternate topology */
+		if (platform->driver->topology_name_prefix) {
+			snprintf(card->topology_shortname, 32, "%s-%s",
+				 platform->driver->topology_name_prefix,
+				 card->name);
+			card->name = card->topology_shortname;
+		}
 	}
 }
 
-- 
2.14.1