Re: [PATCH v2] iio: accel: hid-sensor-accel-3d: Add timestamp

[Jonathan Cameron <jic23@kernel.org>]

On 28/11/16 22:41, Srinivas Pandruvada wrote:
> Added timestamp channel. With this change, each sample has a timestamp.
> This timestamp can be from the sensor hub when present or local kernel
> timestamp. HID sensors can send timestamp with input data using usage id
> HID_USAGE_SENSOR_TIME_TIMESTAMP. This timestamp value is converted to
> nano seconds before pushing this sample to the iio core.
> 
> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Looks good. Applied to the togreg branch of iio.git which will get pushed
out as testing sometime soonish.

Thanks,

Jonathan
> ---
> v2:
> 	Convert timestamp to nano seconds before pushing sample to IIO.
> 
> 
>  drivers/iio/accel/hid-sensor-accel-3d.c            | 32 ++++++++++++++-----
>  .../iio/common/hid-sensors/hid-sensor-attributes.c | 36 +++++++++++++++++++---
>  include/linux/hid-sensor-hub.h                     |  4 +++
>  include/linux/hid-sensor-ids.h                     |  1 +
>  4 files changed, 60 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/iio/accel/hid-sensor-accel-3d.c b/drivers/iio/accel/hid-sensor-accel-3d.c
> index ab1e238..39de79c 100644
> --- a/drivers/iio/accel/hid-sensor-accel-3d.c
> +++ b/drivers/iio/accel/hid-sensor-accel-3d.c
> @@ -42,11 +42,13 @@ struct accel_3d_state {
>  	struct hid_sensor_hub_callbacks callbacks;
>  	struct hid_sensor_common common_attributes;
>  	struct hid_sensor_hub_attribute_info accel[ACCEL_3D_CHANNEL_MAX];
> -	u32 accel_val[ACCEL_3D_CHANNEL_MAX];
> +	/* Reserve for 3 channels + padding + timestamp */
> +	u32 accel_val[ACCEL_3D_CHANNEL_MAX + 3];
>  	int scale_pre_decml;
>  	int scale_post_decml;
>  	int scale_precision;
>  	int value_offset;
> +	int64_t timestamp;
>  };
>  
>  static const u32 accel_3d_addresses[ACCEL_3D_CHANNEL_MAX] = {
> @@ -87,7 +89,8 @@ static const struct iio_chan_spec accel_3d_channels[] = {
>  		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
>  		BIT(IIO_CHAN_INFO_HYSTERESIS),
>  		.scan_index = CHANNEL_SCAN_INDEX_Z,
> -	}
> +	},
> +	IIO_CHAN_SOFT_TIMESTAMP(3)
>  };
>  
>  /* Adjust channel real bits based on report descriptor */
> @@ -192,11 +195,11 @@ static const struct iio_info accel_3d_info = {
>  };
>  
>  /* Function to push data to buffer */
> -static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
> -	int len)
> +static void hid_sensor_push_data(struct iio_dev *indio_dev, void *data,
> +				 int len, int64_t timestamp)
>  {
>  	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
> -	iio_push_to_buffers(indio_dev, data);
> +	iio_push_to_buffers_with_timestamp(indio_dev, data, timestamp);
>  }
>  
>  /* Callback handler to send event after all samples are received and captured */
> @@ -208,10 +211,17 @@ static int accel_3d_proc_event(struct hid_sensor_hub_device *hsdev,
>  	struct accel_3d_state *accel_state = iio_priv(indio_dev);
>  
>  	dev_dbg(&indio_dev->dev, "accel_3d_proc_event\n");
> -	if (atomic_read(&accel_state->common_attributes.data_ready))
> +	if (atomic_read(&accel_state->common_attributes.data_ready)) {
> +		if (!accel_state->timestamp)
> +			accel_state->timestamp = iio_get_time_ns(indio_dev);
> +
>  		hid_sensor_push_data(indio_dev,
> -				accel_state->accel_val,
> -				sizeof(accel_state->accel_val));
> +				     accel_state->accel_val,
> +				     sizeof(accel_state->accel_val),
> +				     accel_state->timestamp);
> +
> +		accel_state->timestamp = 0;
> +	}
>  
>  	return 0;
>  }
> @@ -236,6 +246,12 @@ static int accel_3d_capture_sample(struct hid_sensor_hub_device *hsdev,
>  						*(u32 *)raw_data;
>  		ret = 0;
>  	break;
> +	case HID_USAGE_SENSOR_TIME_TIMESTAMP:
> +		accel_state->timestamp =
> +			hid_sensor_convert_timestamp(
> +					&accel_state->common_attributes,
> +					*(int64_t *)raw_data);
> +	break;
>  	default:
>  		break;
>  	}
> diff --git a/drivers/iio/common/hid-sensors/hid-sensor-attributes.c b/drivers/iio/common/hid-sensors/hid-sensor-attributes.c
> index b5beea53..66e650a 100644
> --- a/drivers/iio/common/hid-sensors/hid-sensor-attributes.c
> +++ b/drivers/iio/common/hid-sensors/hid-sensor-attributes.c
> @@ -58,6 +58,10 @@ static struct {
>  
>  	{HID_USAGE_SENSOR_PRESSURE, 0, 100, 0},
>  	{HID_USAGE_SENSOR_PRESSURE, HID_USAGE_SENSOR_UNITS_PASCAL, 0, 1000000},
> +
> +	{HID_USAGE_SENSOR_TIME_TIMESTAMP, 0, 1000000000, 0},
> +	{HID_USAGE_SENSOR_TIME_TIMESTAMP, HID_USAGE_SENSOR_UNITS_MILLISECOND,
> +		1000000, 0},
>  };
>  
>  static int pow_10(unsigned power)
> @@ -343,6 +347,13 @@ int hid_sensor_format_scale(u32 usage_id,
>  }
>  EXPORT_SYMBOL(hid_sensor_format_scale);
>  
> +int64_t hid_sensor_convert_timestamp(struct hid_sensor_common *st,
> +				     int64_t raw_value)
> +{
> +	return st->timestamp_ns_scale * raw_value;
> +}
> +EXPORT_SYMBOL(hid_sensor_convert_timestamp);
> +
>  static
>  int hid_sensor_get_reporting_interval(struct hid_sensor_hub_device *hsdev,
>  					u32 usage_id,
> @@ -364,6 +375,7 @@ int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev,
>  					struct hid_sensor_common *st)
>  {
>  
> +	struct hid_sensor_hub_attribute_info timestamp;
>  
>  	hid_sensor_get_reporting_interval(hsdev, usage_id, st);
>  
> @@ -382,11 +394,25 @@ int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev,
>  			HID_USAGE_SENSOR_PROP_SENSITIVITY_ABS,
>  			 &st->sensitivity);
>  
> -	hid_dbg(hsdev->hdev, "common attributes: %x:%x, %x:%x, %x:%x %x:%x\n",
> -			st->poll.index, st->poll.report_id,
> -			st->report_state.index, st->report_state.report_id,
> -			st->power_state.index, st->power_state.report_id,
> -			st->sensitivity.index, st->sensitivity.report_id);
> +	sensor_hub_input_get_attribute_info(hsdev,
> +					    HID_INPUT_REPORT, usage_id,
> +					    HID_USAGE_SENSOR_TIME_TIMESTAMP,
> +					    &timestamp);
> +	if (timestamp.index >= 0 && timestamp.report_id) {
> +		int val0, val1;
> +
> +		hid_sensor_format_scale(HID_USAGE_SENSOR_TIME_TIMESTAMP,
> +					&timestamp, &val0, &val1);
> +		st->timestamp_ns_scale = val0;
> +	} else
> +		st->timestamp_ns_scale = 1000000000;
> +
> +	hid_dbg(hsdev->hdev, "common attributes: %x:%x, %x:%x, %x:%x %x:%x %x:%x\n",
> +		st->poll.index, st->poll.report_id,
> +		st->report_state.index, st->report_state.report_id,
> +		st->power_state.index, st->power_state.report_id,
> +		st->sensitivity.index, st->sensitivity.report_id,
> +		timestamp.index, timestamp.report_id);
>  
>  	return 0;
>  }
> diff --git a/include/linux/hid-sensor-hub.h b/include/linux/hid-sensor-hub.h
> index dd85f35..7ef111d 100644
> --- a/include/linux/hid-sensor-hub.h
> +++ b/include/linux/hid-sensor-hub.h
> @@ -232,6 +232,7 @@ struct hid_sensor_common {
>  	atomic_t data_ready;
>  	atomic_t user_requested_state;
>  	struct iio_trigger *trigger;
> +	int timestamp_ns_scale;
>  	struct hid_sensor_hub_attribute_info poll;
>  	struct hid_sensor_hub_attribute_info report_state;
>  	struct hid_sensor_hub_attribute_info power_state;
> @@ -271,4 +272,7 @@ int hid_sensor_format_scale(u32 usage_id,
>  
>  s32 hid_sensor_read_poll_value(struct hid_sensor_common *st);
>  
> +int64_t hid_sensor_convert_timestamp(struct hid_sensor_common *st,
> +				     int64_t raw_value);
> +
>  #endif
> diff --git a/include/linux/hid-sensor-ids.h b/include/linux/hid-sensor-ids.h
> index f2ee90a..9a3a9db 100644
> --- a/include/linux/hid-sensor-ids.h
> +++ b/include/linux/hid-sensor-ids.h
> @@ -95,6 +95,7 @@
>  #define HID_USAGE_SENSOR_TIME_HOUR				0x200525
>  #define HID_USAGE_SENSOR_TIME_MINUTE				0x200526
>  #define HID_USAGE_SENSOR_TIME_SECOND				0x200527
> +#define HID_USAGE_SENSOR_TIME_TIMESTAMP				0x200529
>  
>  /* Units */
>  #define HID_USAGE_SENSOR_UNITS_NOT_SPECIFIED			0x00
>