motion_sense: Stop collection when sensor is powered down

Set collection_rate to 0 when sensor is not in initialized state anymore.
It will prevent the motion_sense task to be neededlessly scheduled.
Export wait_us to be tested.

BUG=b:170703322
BRANCH=kukui
TEST=unit test

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Change-Id: I1dc4c7a07ff30fa10997ef87784114c725f100d5
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2520297
Reviewed-by: Aseda Aboagye <aaboagye@chromium.org>
Reviewed-by: Chen-Tsung Hsieh <chentsung@chromium.org>
Reviewed-by: Yuval Peress <peress@chromium.org>

1 files changed, 12 insertions, 5 deletions

diff --git a/common/motion_sense.c b/common/motion_sense.c
index f708abb26f..df8168d31b 100644
--- a/common/motion_sense.c
+++ b/common/motion_sense.c
@@ -60,6 +60,12 @@ struct mutex g_sensor_mutex;
  */
 test_export_static enum chipset_state_mask sensor_active;
 
+/*
+ * Motion task interval. It does not have to be a global variable,
+ * but it allows to be tested.
+ */
+test_export_static int wait_us;
+
 STATIC_IF(CONFIG_ACCEL_SPOOF_MODE) void print_spoof_mode_status(int id);
 STATIC_IF(CONFIG_GESTURE_DETECTION) void check_and_queue_gestures(
 		uint32_t *event);
@@ -158,13 +164,13 @@ int motion_sense_set_data_rate(struct motion_sensor_t *sensor)
 			BASE_ODR(sensor->config[SENSOR_CONFIG_AP].odr));
 
 	mutex_lock(&g_sensor_mutex);
+	odr = sensor->drv->get_data_rate(sensor);
 	if (ap_odr_mhz)
 		/*
 		 * In case the AP want to run the sensors faster than it can,
 		 * be sure we don't see the ratio to 0.
 		 */
-		sensor->oversampling_ratio = MAX(1,
-			sensor->drv->get_data_rate(sensor) / ap_odr_mhz);
+		sensor->oversampling_ratio = MAX(1, odr / ap_odr_mhz);
 	else
 		sensor->oversampling_ratio = 0;
 
@@ -172,7 +178,6 @@ int motion_sense_set_data_rate(struct motion_sensor_t *sensor)
 	 * Reset last collection: the last collection may be so much in the past
 	 * it may appear to be in the future.
 	 */
-	odr = sensor->drv->get_data_rate(sensor);
 	sensor->collection_rate = odr > 0 ? SECOND * 1000 / odr : 0;
 	sensor->next_collection = ts.le.lo + sensor->collection_rate;
 	sensor->oversampling = 0;
@@ -396,8 +401,10 @@ static void motion_sense_switch_sensor_rate(void)
 			}
 		} else {
 			/* The sensors are being powered off */
-			if (sensor->state == SENSOR_INITIALIZED)
+			if (sensor->state == SENSOR_INITIALIZED) {
+				sensor->collection_rate = 0;
 				sensor->state = SENSOR_NOT_INITIALIZED;
+			}
 		}
 	}
 	motion_sense_set_motion_intervals();
@@ -822,7 +829,7 @@ static void check_and_queue_gestures(uint32_t *event)
  */
 void motion_sense_task(void *u)
 {
-	int i, ret, wait_us, sample_id = 0;
+	int i, ret, sample_id = 0;
 	timestamp_t ts_begin_task, ts_end_task;
 	int32_t time_diff;
 	uint32_t event = 0;