iio: imu: inv_icm42600: fix odr switch when turning buffer off

commit ffd32db upstream.

ODR switch is done in 2 steps when FIFO is on : change the ODR register
value and acknowledge change when reading the FIFO ODR change flag.
When we are switching odr and turning buffer off just afterward, we are
losing the FIFO ODR change flag and ODR switch is blocked.

Fix the issue by force applying any waiting ODR change when turning
buffer off.

Fixes: ec74ae9 ("iio: imu: inv_icm42600: add accurate timestamping")
Signed-off-by: Jean-Baptiste Maneyrol <jean-baptiste.maneyrol@tdk.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: jmaneyrol-invn

drivers/iio/imu/inv_icm42600/inv_icm42600_buffer.c

@@ -371,6 +371,8 @@ static int inv_icm42600_buffer_predisable(struct iio_dev *indio_dev)
 static int inv_icm42600_buffer_postdisable(struct iio_dev *indio_dev)
 {
 	struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);
+	struct inv_icm42600_sensor_state *sensor_st = iio_priv(indio_dev);
+	struct inv_sensors_timestamp *ts = &sensor_st->ts;
 	struct device *dev = regmap_get_device(st->map);
 	unsigned int sensor;
 	unsigned int *watermark;
@@ -392,6 +394,8 @@ static int inv_icm42600_buffer_postdisable(struct iio_dev *indio_dev)
 
 	mutex_lock(&st->lock);
 
+	inv_sensors_timestamp_apply_odr(ts, 0, 0, 0);
+
 	ret = inv_icm42600_buffer_set_fifo_en(st, st->fifo.en & ~sensor);
 	if (ret)
 		goto out_unlock;