CRAS: UCM - Extract and expose ucm_set_use_case function.

The new ucm_set_ues_case function will be used later to change use case
in run-time.  It checks if the UCM config for the requested use case is
availalble, and uses default use case if not.

BUG=chromium:643039
TEST=make check

Change-Id: I499e2be999ad74c2996ee26d56e42e39892a02ee
Reviewed-on: https://chromium-review.googlesource.com/416531
Commit-Ready: Chinyue Chen <chinyue@chromium.org>
Tested-by: Chinyue Chen <chinyue@chromium.org>
Reviewed-by: Dylan Reid <dgreid@chromium.org>

3 files changed, 134 insertions, 6 deletions

diff --git a/cras/src/server/cras_alsa_ucm.c b/cras/src/server/cras_alsa_ucm.c
index a28f8235..896cd197 100644
--- a/cras/src/server/cras_alsa_ucm.c
+++ b/cras/src/server/cras_alsa_ucm.c
@@ -40,6 +40,15 @@ static const char fully_specified_ucm_var[] = "FullySpecifiedUCM";
 static const char main_volume_names[] = "MainVolumeNames";
 static const char enable_htimestamp_var[] = "EnableHtimestamp";
 
+/* Use case verbs corresponding to CRAS_STREAM_TYPE. */
+static const char *use_case_verbs[] = {
+	"HiFi",
+	"Multimedia",
+	"Voice Call",
+	"Voice",
+	"Pro Audio",
+};
+
 /* Represents a list of section names found in UCM. */
 struct section_name {
 	const char* name;
@@ -48,9 +57,16 @@ struct section_name {
 
 struct cras_use_case_mgr {
 	snd_use_case_mgr_t *mgr;
+	const char *name;
+	unsigned int avail_use_cases;
 	enum CRAS_STREAM_TYPE use_case;
 };
 
+static inline const char *uc_verb(struct cras_use_case_mgr *mgr)
+{
+	return use_case_verbs[mgr->use_case];
+}
+
 static int device_enabled(struct cras_use_case_mgr *mgr, const char *dev)
 {
 	const char **list;
@@ -320,6 +336,8 @@ struct cras_use_case_mgr *ucm_create(const char *name)
 {
 	struct cras_use_case_mgr *mgr;
 	int rc;
+	const char **list;
+	int num_verbs, i, j;
 
 	if (!name)
 		return NULL;
@@ -335,14 +353,23 @@ struct cras_use_case_mgr *ucm_create(const char *name)
 		goto cleanup;
 	}
 
-	mgr->use_case = CRAS_STREAM_TYPE_DEFAULT;
+	mgr->name = name;
+	mgr->avail_use_cases = 0;
+	num_verbs = snd_use_case_get_list(mgr->mgr, "_verbs", &list);
+	for (i = 0; i < num_verbs; i += 2) {
+		for (j = 0; j < CRAS_STREAM_NUM_TYPES; ++j) {
+			if (strcmp(list[i], use_case_verbs[j]) == 0)
+				break;
+		}
+		if (j < CRAS_STREAM_NUM_TYPES)
+			mgr->avail_use_cases |= (1 << j);
+	}
+	if (num_verbs > 0)
+		snd_use_case_free_list(list, num_verbs);
 
-	rc = snd_use_case_set(mgr->mgr, "_verb", default_verb);
-	if (rc) {
-		syslog(LOG_ERR, "Can not set verb %s for card %s, rc = %d",
-		       default_verb, name, rc);
+	rc = ucm_set_use_case(mgr, CRAS_STREAM_TYPE_DEFAULT);
+	if (rc)
 		goto cleanup_mgr;
-	}
 
 	return mgr;
 
@@ -359,6 +386,29 @@ void ucm_destroy(struct cras_use_case_mgr *mgr)
 	free(mgr);
 }
 
+int ucm_set_use_case(struct cras_use_case_mgr *mgr,
+		     enum CRAS_STREAM_TYPE use_case)
+{
+	int rc;
+
+	if (mgr->avail_use_cases & (1 << use_case)) {
+		mgr->use_case = use_case;
+	} else {
+		syslog(LOG_ERR, "Unavailable use case %d for card %s",
+		       use_case, mgr->name);
+		return -1;
+	}
+
+	rc = snd_use_case_set(mgr->mgr, "_verb", uc_verb(mgr));
+	if (rc) {
+		syslog(LOG_ERR, "Can not set verb %s for card %s, rc = %d",
+		       uc_verb(mgr), mgr->name, rc);
+		return rc;
+	}
+
+	return 0;
+}
+
 int ucm_swap_mode_exists(struct cras_use_case_mgr *mgr)
 {
 	return ucm_mod_exists_with_suffix(mgr, swap_mode_suffix);
diff --git a/cras/src/server/cras_alsa_ucm.h b/cras/src/server/cras_alsa_ucm.h
index a66db692..95c51eef 100644
--- a/cras/src/server/cras_alsa_ucm.h
+++ b/cras/src/server/cras_alsa_ucm.h
@@ -38,6 +38,16 @@ struct cras_use_case_mgr *ucm_create(const char *name);
  */
 void ucm_destroy(struct cras_use_case_mgr *mgr);
 
+/* Sets the new use case for the given cras_use_case_mgr.
+ * Args:
+ *    mgr - The cras_use_case_mgr pointer returned from ucm_create.
+ *    use_case - The new use case to be set.
+ * Returns:
+ *    0 on success or negative error code on failure.
+ */
+int ucm_set_use_case(struct cras_use_case_mgr *mgr,
+		     enum CRAS_STREAM_TYPE use_case);
+
 /* Checks if modifier for left right swap mode exists in ucm.
  * Args:
  *    mgr - The cras_use_case_mgr pointer returned from alsa_ucm_create.
diff --git a/cras/src/tests/alsa_ucm_unittest.cc b/cras/src/tests/alsa_ucm_unittest.cc
index 933a84c8..8e604253 100644
--- a/cras/src/tests/alsa_ucm_unittest.cc
+++ b/cras/src/tests/alsa_ucm_unittest.cc
@@ -37,6 +37,7 @@ static unsigned snd_use_case_free_list_called;
 static std::vector<std::string> list_devices_callback_names;
 static std::vector<void*> list_devices_callback_args;
 static struct cras_use_case_mgr cras_ucm_mgr;
+static const char *avail_verbs[] = { "HiFi", "Comment for Verb1" };
 
 static void ResetStubData() {
   snd_use_case_mgr_open_called = 0;
@@ -51,6 +52,8 @@ static void ResetStubData() {
   snd_use_case_get_value.clear();
   fake_list.clear();
   fake_list_size.clear();
+  fake_list["_verbs"] = avail_verbs;
+  fake_list_size["_verbs"] = 2;
   list_devices_callback_names.clear();
   list_devices_callback_args.clear();
   snd_use_case_mgr_open_mgr_ptr = reinterpret_cast<snd_use_case_mgr_t*>(0x55);
@@ -1267,6 +1270,71 @@ TEST(AlsaUcm, GetSectionsBadPCM) {
   EXPECT_EQ(NULL, sections);
 }
 
+TEST(AlsaUcm, CheckUseCaseVerbs) {
+  struct cras_use_case_mgr *mgr = &cras_ucm_mgr;
+
+  /* Verifies the mapping between stream types and verbs are correct. */
+  mgr->use_case = CRAS_STREAM_TYPE_DEFAULT;
+  EXPECT_EQ(0, strcmp("HiFi", uc_verb(mgr)));
+  mgr->use_case = CRAS_STREAM_TYPE_MULTIMEDIA;
+  EXPECT_EQ(0, strcmp("Multimedia", uc_verb(mgr)));
+  mgr->use_case = CRAS_STREAM_TYPE_VOICE_COMMUNICATION;
+  EXPECT_EQ(0, strcmp("Voice Call", uc_verb(mgr)));
+  mgr->use_case = CRAS_STREAM_TYPE_VOICE_RECOGNITION;
+  EXPECT_EQ(0, strcmp("Voice", uc_verb(mgr)));
+  mgr->use_case = CRAS_STREAM_TYPE_PRO_AUDIO;
+  EXPECT_EQ(0, strcmp("Pro Audio", uc_verb(mgr)));
+}
+
+TEST(AlsaUcm, GetAvailUseCases) {
+  struct cras_use_case_mgr *mgr;
+  const char *verbs[] = { "HiFi", "Comment for Verb1",
+                          "Voice Call", "Comment for Verb2",
+                          "Voice", "Comment for Verb3" };
+
+  ResetStubData();
+
+  fake_list["_verbs"] = verbs;
+  fake_list_size["_verbs"] = 6;
+
+  mgr = ucm_create("foo");
+  EXPECT_EQ(0x0D, mgr->avail_use_cases);
+  ucm_destroy(mgr);
+}
+
+TEST(AlsaUcm, SetUseCase) {
+  struct cras_use_case_mgr *mgr;
+  const char *verbs[] = { "HiFi", "Comment for Verb1",
+                          "Voice Call", "Comment for Verb2",
+                          "Voice", "Comment for Verb3" };
+  int rc;
+
+  ResetStubData();
+
+  fake_list["_verbs"] = verbs;
+  fake_list_size["_verbs"] = 6;
+
+  mgr = ucm_create("foo");
+  EXPECT_EQ(snd_use_case_set_param[0],
+      std::make_pair(std::string("_verb"), std::string("HiFi")));
+
+  rc = ucm_set_use_case(mgr, CRAS_STREAM_TYPE_VOICE_COMMUNICATION);
+  EXPECT_EQ(0, rc);
+  EXPECT_EQ(mgr->use_case, CRAS_STREAM_TYPE_VOICE_COMMUNICATION);
+  EXPECT_EQ(snd_use_case_set_param[1],
+      std::make_pair(std::string("_verb"), std::string("Voice Call")));
+
+  /* Request unavailable use case will fail. */
+  rc = ucm_set_use_case(mgr, CRAS_STREAM_TYPE_PRO_AUDIO);
+  EXPECT_EQ(-1, rc);
+  /* cras_use_case_mgr's use case should not be changed. */
+  EXPECT_EQ(mgr->use_case, CRAS_STREAM_TYPE_VOICE_COMMUNICATION);
+  /* And snd_use_case_set not being called. */
+  EXPECT_EQ(2, snd_use_case_set_param.size());
+
+  ucm_destroy(mgr);
+}
+
 /* Stubs */
 
 extern "C" {