Re: [PATCH v3 3/6] iio: pressure: add SCALE and RAW values for channels

Jonathan Cameron
2024-03-14T14:48:53Z

On Wed, 13 Mar 2024 18:40:04 +0100
Vasileios Amoiridis <vassilisamir@gmail.com> wrote:

> Add extra IIO_CHAN_INFO_SCALE and IIO_CHAN_INFO_RAW in order to be
> able to calculate the processed value with standard userspace IIO
> tools. Can be used for triggered buffers as well.
>
> Signed-off-by: Vasileios Amoiridis <vassilisamir@gmail.com>
> ---
> drivers/iio/pressure/bmp280-core.c | 58 ++++++++++++++++++++++++++++++
> 1 file changed, 58 insertions(+)
>
> diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
> index dfd845acfa22..6d7734f867bc 100644
> --- a/drivers/iio/pressure/bmp280-core.c
> +++ b/drivers/iio/pressure/bmp280-core.c
> @@ -138,16 +138,22 @@ static const struct iio_chan_spec bmp280_channels[] = {
> {
> .type = IIO_PRESSURE,
> .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |

Next to each (or at least the first) existing entry for PROCESSED add a
comment that says it is maintained for ABI backwards compatibility reasons.
I really don't want people copying the result of this patch into new drivers
- we've ended up here because of a less than ideal decision in the past, that
history doesn't apply to other drivers.

> + BIT(IIO_CHAN_INFO_RAW) |
> + BIT(IIO_CHAN_INFO_SCALE) |
> BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
> },
> {
> .type = IIO_TEMP,
> .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
> + BIT(IIO_CHAN_INFO_RAW) |
> + BIT(IIO_CHAN_INFO_SCALE) |
> BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
> },
> {
> .type = IIO_HUMIDITYRELATIVE,
> .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
> + BIT(IIO_CHAN_INFO_RAW) |
> + BIT(IIO_CHAN_INFO_SCALE) |
> BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
> },
> };
> @@ -156,6 +162,8 @@ static const struct iio_chan_spec bmp380_channels[] = {
> {
> .type = IIO_PRESSURE,
> .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
> + BIT(IIO_CHAN_INFO_RAW) |
> + BIT(IIO_CHAN_INFO_SCALE) |
> BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
> .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
> BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
> @@ -163,6 +171,8 @@ static const struct iio_chan_spec bmp380_channels[] = {
> {
> .type = IIO_TEMP,
> .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
> + BIT(IIO_CHAN_INFO_RAW) |
> + BIT(IIO_CHAN_INFO_SCALE) |
> BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
> .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
> BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
> @@ -170,6 +180,8 @@ static const struct iio_chan_spec bmp380_channels[] = {
> {
> .type = IIO_HUMIDITYRELATIVE,
> .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
> + BIT(IIO_CHAN_INFO_RAW) |
> + BIT(IIO_CHAN_INFO_SCALE) |
> BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
> .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
> BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
> @@ -485,6 +497,52 @@ static int bmp280_read_raw(struct iio_dev *indio_dev,
> break;
> }
> break;
> + case IIO_CHAN_INFO_RAW:
> + switch (chan->type) {
> + case IIO_HUMIDITYRELATIVE:
> + *val = data->chip_info->read_humid(data);
> + ret = IIO_VAL_INT;
> + break;
> + case IIO_PRESSURE:
> + *val = data->chip_info->read_press(data);
> + ret = IIO_VAL_INT;
> + break;
> + case IIO_TEMP:
> + *val = data->chip_info->read_temp(data);
> + ret = IIO_VAL_INT;
> + break;
> + default:
> + ret = -EINVAL;
> + break;
> + }
> + break;
> + case IIO_CHAN_INFO_SCALE:
> + switch (chan->type) {
> + case IIO_HUMIDITYRELATIVE:
> + *val = data->chip_info->humid_coeffs[0];
> + *val2 = data->chip_info->humid_coeffs[1];
> + ret = IIO_VAL_FRACTIONAL;
> + break;
> + case IIO_PRESSURE:
> + *val = data->chip_info->press_coeffs[0];
> + *val2 = data->chip_info->press_coeffs[1];
> + ret = IIO_VAL_FRACTIONAL;
> + break;
> + case IIO_TEMP:
> + *val = data->chip_info->temp_coeffs[0];
> + *val2 = data->chip_info->temp_coeffs[1];
> +
> + if (!strcmp(indio_dev->name, "bmp580"))
> + ret = IIO_VAL_FRACTIONAL_LOG2;
> + else
> + ret = IIO_VAL_FRACTIONAL;
> +
> + break;
> + default:
> + ret = -EINVAL;
> + break;
> + }
> + break;
> case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
> switch (chan->type) {