CRAS: Add a flag to pause hotword detection at system suspend

This patch adds a server state flag to optionally pause
hotword detection at system suspend.

Default value of the flag can be specified in board.ini

BUG=b:178128172
TEST=Set the flag in board.ini on Delbin and verify
if hotword can wake up the device from suspend.
Repeated suspend/resume on Delbin with the flag set to 1

Change-Id: I6820c92dd418f51108b374ff186a2b82da031399
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/adhd/+/2652049
Tested-by: Ben Zhang <benzh@chromium.org>
Commit-Queue: Ben Zhang <benzh@chromium.org>
Reviewed-by: Cheng-Yi Chiang <cychiang@chromium.org>

8 files changed, 126 insertions, 0 deletions

diff --git a/cras/src/common/cras_types.h b/cras/src/common/cras_types.h
index 53f2f6aa..7c8a4229 100644
--- a/cras/src/common/cras_types.h
+++ b/cras/src/common/cras_types.h
@@ -574,6 +574,11 @@ struct __attribute__((__packed__)) cras_audio_thread_snapshot_buffer {
  *    num_input_streams_with_permission - An array containing numbers of input
  *        streams with permission in each client type.
  *    noise_cancellation_enabled - Whether or not Noise Cancellation is enabled.
+ *    hotword_pause_at_suspend - 1 = Pause hotword detection when the system
+ *        suspends. Hotword detection is resumed after system resumes.
+ *        0 - Hotword detection is allowed to continue running after system
+ *        suspends, so a detected hotword can wake up the device.
+ *
  */
 #define CRAS_SERVER_STATE_VERSION 2
 struct __attribute__((packed, aligned(4))) cras_server_state {
@@ -614,6 +619,7 @@ struct __attribute__((packed, aligned(4))) cras_server_state {
 	struct main_thread_debug_info main_thread_debug_info;
 	uint32_t num_input_streams_with_permission[CRAS_NUM_CLIENT_TYPE];
 	int32_t noise_cancellation_enabled;
+	int32_t hotword_pause_at_suspend;
 };
 
 /* Actions for card add/remove/change. */
diff --git a/cras/src/server/config/cras_board_config.c b/cras/src/server/config/cras_board_config.c
index 14d3fa0c..e36ea3cf 100644
--- a/cras/src/server/config/cras_board_config.c
+++ b/cras/src/server/config/cras_board_config.c
@@ -14,6 +14,7 @@ static const int32_t AEC_SUPPORTED_DEFAULT = 0;
 static const int32_t AEC_GROUP_ID_DEFAULT = -1;
 static const int32_t BLUETOOTH_WBS_ENABLED_INI_DEFAULT = 1;
 static const int32_t BLUETOOTH_DEPRIORITIZE_WBS_MIC_INI_DEFAULT = 0;
+static const int32_t HOTWORD_PAUSE_AT_SUSPEND_DEFAULT = 0;
 
 #define CONFIG_NAME "board.ini"
 #define DEFAULT_OUTPUT_BUF_SIZE_INI_KEY "output:default_output_buffer_size"
@@ -22,6 +23,7 @@ static const int32_t BLUETOOTH_DEPRIORITIZE_WBS_MIC_INI_DEFAULT = 0;
 #define BLUETOOTH_WBS_ENABLED_INI_KEY "bluetooth:wbs_enabled"
 #define BLUETOOTH_DEPRIORITIZE_WBS_MIC_INI_KEY "bluetooth:deprioritize_wbs_mic"
 #define UCM_IGNORE_SUFFIX_KEY "ucm:ignore_suffix"
+#define HOTWORD_PAUSE_AT_SUSPEND "hotword:pause_at_suspend"
 
 void cras_board_config_get(const char *config_path,
 			   struct cras_board_config *board_config)
@@ -85,6 +87,11 @@ void cras_board_config_get(const char *config_path,
 			syslog(LOG_ERR, "Failed to call strdup: %d", errno);
 	}
 
+	snprintf(ini_key, MAX_INI_KEY_LENGTH, HOTWORD_PAUSE_AT_SUSPEND);
+	ini_key[MAX_INI_KEY_LENGTH] = 0;
+	board_config->hotword_pause_at_suspend = iniparser_getint(
+		ini, ini_key, HOTWORD_PAUSE_AT_SUSPEND_DEFAULT);
+
 	iniparser_freedict(ini);
 	syslog(LOG_DEBUG, "Loaded ini file %s", ini_name);
 }
diff --git a/cras/src/server/config/cras_board_config.h b/cras/src/server/config/cras_board_config.h
index 2ecde265..d4bd8496 100644
--- a/cras/src/server/config/cras_board_config.h
+++ b/cras/src/server/config/cras_board_config.h
@@ -15,6 +15,7 @@ struct cras_board_config {
 	int32_t bt_wbs_enabled;
 	int32_t deprioritize_bt_wbs_mic;
 	char *ucm_ignore_suffix;
+	int32_t hotword_pause_at_suspend;
 };
 
 /* Gets a configuration based on the config file specified.
diff --git a/cras/src/server/cras_iodev_list.c b/cras/src/server/cras_iodev_list.c
index 17b04ecb..d887dfad 100644
--- a/cras/src/server/cras_iodev_list.c
+++ b/cras/src/server/cras_iodev_list.c
@@ -91,6 +91,9 @@ static int stream_list_suspended = 0;
 static const unsigned int INIT_DEV_DELAY_MS = 1000;
 /* Flag to indicate that hotword streams are suspended. */
 static int hotword_suspended = 0;
+/* Flag to indicate that suspended hotword streams should be auto-resumed at
+ * system resume. */
+static int hotword_auto_resume = 0;
 
 static void idle_dev_check(struct cras_timer *timer, void *data);
 
@@ -491,6 +494,11 @@ static void suspend_devs()
 		if (rstream->is_pinned) {
 			struct cras_iodev *dev;
 
+			/* Skip closing hotword stream in the first pass.
+			 * Closing an input device may resume hotword stream
+			 * with its post_close_iodev_hook so we should deal
+			 * with hotword stream in the second pass.
+			 */
 			if ((rstream->flags & HOTWORD_STREAM) == HOTWORD_STREAM)
 				continue;
 
@@ -514,6 +522,14 @@ static void suspend_devs()
 	DL_FOREACH (enabled_devs[CRAS_STREAM_INPUT], edev) {
 		close_dev(edev->dev);
 	}
+
+	/* Doing this check after all the other enabled iodevs are closed to
+	 * ensure preempted hotword streams obey the pause_at_suspend flag.
+	 */
+	if (cras_system_get_hotword_pause_at_suspend()) {
+		cras_iodev_list_suspend_hotword_streams();
+		hotword_auto_resume = 1;
+	}
 }
 
 static int stream_added_cb(struct cras_rstream *rstream);
@@ -528,6 +544,14 @@ static void resume_devs()
 
 	MAINLOG(main_log, MAIN_THREAD_RESUME_DEVS, 0, 0, 0);
 
+	/* Auto-resume based on the local flag in case the system state flag has
+	 * changed.
+	 */
+	if (hotword_auto_resume) {
+		cras_iodev_list_resume_hotword_stream();
+		hotword_auto_resume = 0;
+	}
+
 	/*
 	 * To remove the short popped noise caused by applications that can not
 	 * stop playback "right away" after resume, we mute all output devices
diff --git a/cras/src/server/cras_system_state.c b/cras/src/server/cras_system_state.c
index 22df0001..587c225f 100644
--- a/cras/src/server/cras_system_state.c
+++ b/cras/src/server/cras_system_state.c
@@ -160,6 +160,8 @@ void cras_system_state_init(const char *device_config_dir, const char *shm_name,
 	exp_state->deprioritize_bt_wbs_mic =
 		board_config.deprioritize_bt_wbs_mic;
 	exp_state->noise_cancellation_enabled = 0;
+	exp_state->hotword_pause_at_suspend =
+		board_config.hotword_pause_at_suspend;
 
 	if ((rc = pthread_mutex_init(&state.update_lock, 0) != 0)) {
 		syslog(LOG_ERR, "Fatal: system state mutex init");
@@ -427,6 +429,16 @@ bool cras_system_check_ignore_ucm_suffix(const char *card_name)
 	return false;
 }
 
+bool cras_system_get_hotword_pause_at_suspend()
+{
+	return !!state.exp_state->hotword_pause_at_suspend;
+}
+
+void cras_system_set_hotword_pause_at_suspend(bool pause)
+{
+	state.exp_state->hotword_pause_at_suspend = pause;
+}
+
 int cras_system_add_alsa_card(struct cras_alsa_card_info *alsa_card_info)
 {
 	struct card_list *card;
diff --git a/cras/src/server/cras_system_state.h b/cras/src/server/cras_system_state.h
index 23fdd8e5..bd09395c 100644
--- a/cras/src/server/cras_system_state.h
+++ b/cras/src/server/cras_system_state.h
@@ -143,6 +143,12 @@ bool cras_system_get_noise_cancellation_enabled();
 /* Checks if the card ignores the ucm suffix. */
 bool cras_system_check_ignore_ucm_suffix(const char *card_name);
 
+/* Returns true if hotword detection is paused at system suspend. */
+bool cras_system_get_hotword_pause_at_suspend();
+
+/* Sets whether to pause hotword detection at system suspend. */
+void cras_system_set_hotword_pause_at_suspend(bool pause);
+
 /* Adds a card at the given index to the system.  When a new card is found
  * (through a udev event notification) this will add the card to the system,
  * causing its devices to become available for playback/capture.
diff --git a/cras/src/tests/control_rclient_unittest.cc b/cras/src/tests/control_rclient_unittest.cc
index d6067304..63e3c8f0 100644
--- a/cras/src/tests/control_rclient_unittest.cc
+++ b/cras/src/tests/control_rclient_unittest.cc
@@ -972,4 +972,6 @@ void detect_rtc_stream_pair(struct stream_list* list,
   return;
 }
 
+void cras_system_set_hotword_pause_at_suspend(bool pause) {}
+
 }  // extern "C"
diff --git a/cras/src/tests/iodev_list_unittest.cc b/cras/src/tests/iodev_list_unittest.cc
index 272537fc..5dbc7c8f 100644
--- a/cras/src/tests/iodev_list_unittest.cc
+++ b/cras/src/tests/iodev_list_unittest.cc
@@ -95,6 +95,7 @@ static struct cras_rstream* audio_thread_disconnect_stream_stream;
 static int audio_thread_disconnect_stream_called;
 static struct cras_iodev fake_sco_in_dev, fake_sco_out_dev;
 static struct cras_ionode fake_sco_in_node, fake_sco_out_node;
+static int server_state_hotword_pause_at_suspend;
 
 int dev_idx_in_vector(std::vector<unsigned int> v, unsigned int idx) {
   return std::find(v.begin(), v.end(), idx) != v.end();
@@ -238,6 +239,7 @@ class IoDevTestSuite : public testing::Test {
     mock_empty_iodev[1].state = CRAS_IODEV_STATE_CLOSE;
     mock_empty_iodev[1].update_active_node = update_active_node;
     mock_hotword_iodev.update_active_node = update_active_node;
+    server_state_hotword_pause_at_suspend = 0;
   }
 
   virtual void TearDown() {
@@ -1942,6 +1944,68 @@ TEST_F(IoDevTestSuite, GetSCOPCMIodevs) {
   cras_iodev_list_deinit();
 }
 
+TEST_F(IoDevTestSuite, HotwordStreamsPausedAtSystemSuspend) {
+  struct cras_rstream rstream;
+  struct cras_rstream* stream_list = NULL;
+  cras_iodev_list_init();
+
+  node1.type = CRAS_NODE_TYPE_HOTWORD;
+  d1_.direction = CRAS_STREAM_INPUT;
+  EXPECT_EQ(0, cras_iodev_list_add_input(&d1_));
+
+  d1_.format = &fmt_;
+
+  memset(&rstream, 0, sizeof(rstream));
+  rstream.is_pinned = 1;
+  rstream.pinned_dev_idx = d1_.info.idx;
+  rstream.flags = HOTWORD_STREAM;
+
+  /* Add a hotword stream. */
+  EXPECT_EQ(0, stream_add_cb(&rstream));
+  EXPECT_EQ(1, audio_thread_add_stream_called);
+  EXPECT_EQ(&d1_, audio_thread_add_stream_dev);
+  EXPECT_EQ(&rstream, audio_thread_add_stream_stream);
+
+  DL_APPEND(stream_list, &rstream);
+  stream_list_get_ret = stream_list;
+
+  server_state_hotword_pause_at_suspend = 1;
+
+  /* Trigger system suspend. Verify hotword stream is moved to empty dev. */
+  observer_ops->suspend_changed(NULL, 1);
+  EXPECT_EQ(1, audio_thread_disconnect_stream_called);
+  EXPECT_EQ(&rstream, audio_thread_disconnect_stream_stream);
+  EXPECT_EQ(&d1_, audio_thread_disconnect_stream_dev);
+  EXPECT_EQ(2, audio_thread_add_stream_called);
+  EXPECT_EQ(&rstream, audio_thread_add_stream_stream);
+  EXPECT_EQ(&mock_hotword_iodev, audio_thread_add_stream_dev);
+
+  /* Trigger system resume. Verify hotword stream is moved to real dev.*/
+  observer_ops->suspend_changed(NULL, 0);
+  EXPECT_EQ(2, audio_thread_disconnect_stream_called);
+  EXPECT_EQ(&rstream, audio_thread_disconnect_stream_stream);
+  EXPECT_EQ(&mock_hotword_iodev, audio_thread_disconnect_stream_dev);
+  EXPECT_EQ(3, audio_thread_add_stream_called);
+  EXPECT_EQ(&rstream, audio_thread_add_stream_stream);
+  EXPECT_EQ(&d1_, audio_thread_add_stream_dev);
+
+  server_state_hotword_pause_at_suspend = 0;
+  audio_thread_disconnect_stream_called = 0;
+  audio_thread_add_stream_called = 0;
+
+  /* Trigger system suspend. Verify hotword stream is not touched. */
+  observer_ops->suspend_changed(NULL, 1);
+  EXPECT_EQ(0, audio_thread_disconnect_stream_called);
+  EXPECT_EQ(0, audio_thread_add_stream_called);
+
+  /* Trigger system resume. Verify hotword stream is not touched.*/
+  observer_ops->suspend_changed(NULL, 0);
+  EXPECT_EQ(0, audio_thread_disconnect_stream_called);
+  EXPECT_EQ(0, audio_thread_add_stream_called);
+
+  cras_iodev_list_deinit();
+}
+
 }  //  namespace
 
 int main(int argc, char** argv) {
@@ -2246,4 +2310,8 @@ int clock_gettime(clockid_t clk_id, struct timespec* tp) {
   return 0;
 }
 
+bool cras_system_get_hotword_pause_at_suspend() {
+  return !!server_state_hotword_pause_at_suspend;
+}
+
 }  // extern "C"