iio: imu: st_lsm6dsx: do not power-off accel if events are enabled

Do not power-off accel unconditionally if wake-up events are enabled
powering off the hw FIFO. At the same time do not power-off the accel
sensor if it is 'batched' in the hw FIFO disabling sensor events

Fixes: b5969abfa8 ("iio: imu: st_lsm6dsx: add motion events")
Tested-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c

@@ -1447,8 +1447,9 @@ st_lsm6dsx_set_odr(struct st_lsm6dsx_sensor *sensor, u32 req_odr)
 	return st_lsm6dsx_update_bits_locked(hw, reg->addr, reg->mask, data);
 }
 
-int st_lsm6dsx_sensor_set_enable(struct st_lsm6dsx_sensor *sensor,
-				 bool enable)
+static int
+__st_lsm6dsx_sensor_set_enable(struct st_lsm6dsx_sensor *sensor,
+			       bool enable)
 {
 	struct st_lsm6dsx_hw *hw = sensor->hw;
 	u32 odr = enable ? sensor->odr : 0;
@@ -1466,6 +1467,26 @@ int st_lsm6dsx_sensor_set_enable(struct st_lsm6dsx_sensor *sensor,
 	return 0;
 }
 
+static int
+st_lsm6dsx_check_events(struct st_lsm6dsx_sensor *sensor, bool enable)
+{
+	struct st_lsm6dsx_hw *hw = sensor->hw;
+
+	if (sensor->id == ST_LSM6DSX_ID_GYRO || enable)
+		return 0;
+
+	return hw->enable_event;
+}
+
+int st_lsm6dsx_sensor_set_enable(struct st_lsm6dsx_sensor *sensor,
+				 bool enable)
+{
+	if (st_lsm6dsx_check_events(sensor, enable))
+		return 0;
+
+	return __st_lsm6dsx_sensor_set_enable(sensor, enable);
+}
+
 static int st_lsm6dsx_read_oneshot(struct st_lsm6dsx_sensor *sensor,
 				   u8 addr, int *val)
 {
@@ -1661,7 +1682,7 @@ st_lsm6dsx_write_event_config(struct iio_dev *iio_dev,
 	struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev);
 	struct st_lsm6dsx_hw *hw = sensor->hw;
 	u8 enable_event;
-	int err = 0;
+	int err;
 
 	if (type != IIO_EV_TYPE_THRESH)
 		return -EINVAL;
@@ -1689,7 +1710,8 @@ st_lsm6dsx_write_event_config(struct iio_dev *iio_dev,
 		return err;
 
 	mutex_lock(&hw->conf_lock);
-	err = st_lsm6dsx_sensor_set_enable(sensor, state);
+	if (enable_event || !(hw->fifo_mask & BIT(sensor->id)))
+		err = __st_lsm6dsx_sensor_set_enable(sensor, state);
 	mutex_unlock(&hw->conf_lock);
 	if (err < 0)
 		return err;