[PATCH 2/4] iio: hid-sensor-humidity: Get sample timestamp from sensor hub

[Ye Xiang <xiang.ye@intel.com>]

Try to get sample timestamp from sensor hub first, if failed
then use system timestamp.

Signed-off-by: Ye Xiang <xiang.ye@intel.com>
---
 drivers/iio/humidity/hid-sensor-humidity.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/humidity/hid-sensor-humidity.c b/drivers/iio/humidity/hid-sensor-humidity.c
index 74383abc0d44..f7b4c76ed94f 100644
--- a/drivers/iio/humidity/hid-sensor-humidity.c
+++ b/drivers/iio/humidity/hid-sensor-humidity.c
@@ -23,6 +23,7 @@ struct hid_humidity_state {
 	int scale_post_decml;
 	int scale_precision;
 	int value_offset;
+	s64 timestamp;
 };
 
 static const u32 humidity_sensitivity_addresses[] = {
@@ -131,9 +132,14 @@ static int humidity_proc_event(struct hid_sensor_hub_device *hsdev,
 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 	struct hid_humidity_state *humid_st = iio_priv(indio_dev);
 
-	if (atomic_read(&humid_st->common_attributes.data_ready))
+	if (atomic_read(&humid_st->common_attributes.data_ready)) {
+		if (!humid_st->timestamp)
+			humid_st->timestamp = iio_get_time_ns(indio_dev);
+
 		iio_push_to_buffers_with_timestamp(indio_dev, &humid_st->scan,
-						   iio_get_time_ns(indio_dev));
+						   humid_st->timestamp);
+		humid_st->timestamp = 0;
+	}
 
 	return 0;
 }
@@ -151,6 +157,10 @@ static int humidity_capture_sample(struct hid_sensor_hub_device *hsdev,
 		humid_st->scan.humidity_data = *(s32 *)raw_data;
 
 		return 0;
+	case HID_USAGE_SENSOR_TIME_TIMESTAMP:
+		humid_st->timestamp = hid_sensor_convert_timestamp(&humid_st->common_attributes,
+								   *(s64 *)raw_data);
+		return 0;
 	default:
 		return -EINVAL;
 	}
-- 
2.17.1