ASoC: SOF: don't check the existence of dummy topology

Monolithic topology is not needed if function topology is used. Instead
of creating a dummy topology in the file system, we can skip the
existence check in the kernel.

Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>

Author: bardliao

sound/soc/sof/fw-file-profile.c

@@ -73,6 +73,10 @@ static int sof_test_topology_file(struct device *dev,
 	if (!profile->tplg_path || !profile->tplg_name)
 		return 0;
 
+	/* Dummy topology does not exist and should not be used */
+	if (strstr(profile->tplg_name, "dummy"))
+		return 0;
+
 	tplg_filename = kasprintf(GFP_KERNEL, "%s/%s", profile->tplg_path,
 				  profile->tplg_name);
 	if (!tplg_filename)

sound/soc/sof/topology.c

@@ -2523,6 +2523,11 @@ int snd_sof_load_topology(struct snd_soc_component *scomp, const char *file)
 	 * callback or the callback returns 0.
 	 */
 	if (!tplg_cnt) {
+		if (strstr(file, "dummy")) {
+			dev_err(scomp->dev,
+				"Function topology is required, please upgrade sof-firmware\n");
+			return -EINVAL;
+		}
 		tplg_files[0] = file;
 		tplg_cnt = 1;
 		dev_info(scomp->dev, "loading topology: %s\n", file);