Re: [PATCH v2 1/1] iio/scmi: Add reading "raw" attribute.

[Jonathan Cameron <jic23@kernel.org>]

On Mon, 27 Sep 2021 16:22:02 +0300
Andriy Tryshnivskyy <andriy.tryshnivskyy@opensynergy.com> wrote:

> Add IIO_CHAN_INFO_RAW to the mask and implement corresponding
> reading "raw" attribute in scmi_iio_read_raw.
> 
> Signed-off-by: Andriy Tryshnivskyy <andriy.tryshnivskyy@opensynergy.com>
Hi Andriy,

Looks good to me, but I'll leave it on list to get feedback form the
driver maintainer for this one.

Feel free to poke if no reply in next 2 weeks.

Thanks,

Jonathan

> ---
>  drivers/iio/common/scmi_sensors/scmi_iio.c | 45 +++++++++++++++++++++-
>  1 file changed, 44 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/common/scmi_sensors/scmi_iio.c b/drivers/iio/common/scmi_sensors/scmi_iio.c
> index 7cf2bf282cef..c6a9dc6ad140 100644
> --- a/drivers/iio/common/scmi_sensors/scmi_iio.c
> +++ b/drivers/iio/common/scmi_sensors/scmi_iio.c
> @@ -286,6 +286,9 @@ static int scmi_iio_read_raw(struct iio_dev *iio_dev,
>  	struct scmi_iio_priv *sensor = iio_priv(iio_dev);
>  	s8 scale;
>  	int ret;
> +	int err;
> +	u32 sensor_config;
> +	struct scmi_sensor_reading readings[SCMI_IIO_NUM_OF_AXIS];
>  
>  	switch (mask) {
>  	case IIO_CHAN_INFO_SCALE:
> @@ -300,6 +303,45 @@ static int scmi_iio_read_raw(struct iio_dev *iio_dev,
>  	case IIO_CHAN_INFO_SAMP_FREQ:
>  		ret = scmi_iio_get_odr_val(iio_dev, val, val2);
>  		return ret ? ret : IIO_VAL_INT_PLUS_MICRO;
> +	case IIO_CHAN_INFO_RAW:
> +		sensor_config = FIELD_PREP(SCMI_SENS_CFG_SENSOR_ENABLED_MASK,
> +					   SCMI_SENS_CFG_SENSOR_ENABLE);
> +		err = sensor->handle->sensor_ops->config_set(
> +			sensor->handle, sensor->sensor_info->id, sensor_config);
> +		if (err) {
> +			dev_err(&iio_dev->dev,
> +				"Error in enabling sensor %s err %d",
> +				sensor->sensor_info->name, err);
> +			return err;
> +		}
> +
> +		err = sensor->handle->sensor_ops->reading_get_timestamped(
> +			sensor->handle, sensor->sensor_info->id,
> +			sensor->sensor_info->num_axis, readings);
> +		if (err) {
> +			dev_err(&iio_dev->dev,
> +				"Error in reading raw attribute for sensor %s err %d",
> +				sensor->sensor_info->name, err);
> +			return err;
> +		}
> +
> +		sensor_config = FIELD_PREP(SCMI_SENS_CFG_SENSOR_ENABLED_MASK,
> +					   SCMI_SENS_CFG_SENSOR_DISABLE);
> +		err = sensor->handle->sensor_ops->config_set(
> +			sensor->handle, sensor->sensor_info->id, sensor_config);
> +		if (err) {
> +			dev_err(&iio_dev->dev,
> +				"Error in enabling sensor %s err %d",
> +				sensor->sensor_info->name, err);
> +			return err;
> +		}
> +		/* Check if raw value fits 32 bits */
> +		if (readings[ch->scan_index].value < INT_MIN ||
> +		    readings[ch->scan_index].value > INT_MAX)
> +			return -ERANGE;
> +		/* Use 32-bit value, since practically there is no need in 64 bits */
> +		*val = (int)readings[ch->scan_index].value;
> +		return IIO_VAL_INT;
>  	default:
>  		return -EINVAL;
>  	}
> @@ -381,7 +423,8 @@ static void scmi_iio_set_data_channel(struct iio_chan_spec *iio_chan,
>  	iio_chan->type = type;
>  	iio_chan->modified = 1;
>  	iio_chan->channel2 = mod;
> -	iio_chan->info_mask_separate = BIT(IIO_CHAN_INFO_SCALE);
> +	iio_chan->info_mask_separate =
> +		BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_RAW);
>  	iio_chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ);
>  	iio_chan->info_mask_shared_by_type_available =
>  		BIT(IIO_CHAN_INFO_SAMP_FREQ);