Re: [PATCH v6 1/4] iio: cros_ec: Add sign vector in core for backward compatibility

[Jonathan Cameron <jic23@kernel.org>]

On Mon, 15 Jul 2019 16:14:51 -0700
Gwendal Grignou <gwendal@chromium.org> wrote:

> To allow cros_ec iio core library to be used with legacy device, add a
> vector to rotate sensor data if necessary: legacy devices are not
> reporting data in HTML5/Android sensor referential.
> 
> Check the data is not rotated on recent chromebooks that use the HTML5
> standard to present sensor data.
> 
> Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
> Reviewed-by: Douglas Anderson <dianders@chromium.org>
Applied to the togreg branch of iio.git and pushed out as testing for the
autobuilders to play with it.

Thanks,

Jonathan

> ---
>  drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c | 4 ++++
>  include/linux/iio/common/cros_ec_sensors_core.h           | 1 +
>  2 files changed, 5 insertions(+)
> 
> diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
> index 719a0df5aeeb..e8a4d78659c8 100644
> --- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
> +++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
> @@ -66,6 +66,9 @@ int cros_ec_sensors_core_init(struct platform_device *pdev,
>  		}
>  		state->type = state->resp->info.type;
>  		state->loc = state->resp->info.location;
> +
> +		/* Set sign vector, only used for backward compatibility. */
> +		memset(state->sign, 1, CROS_EC_SENSOR_MAX_AXIS);
>  	}
>  
>  	return 0;
> @@ -254,6 +257,7 @@ static int cros_ec_sensors_read_data_unsafe(struct iio_dev *indio_dev,
>  		if (ret < 0)
>  			return ret;
>  
> +		*data *= st->sign[i];
>  		data++;
>  	}
>  
> diff --git a/include/linux/iio/common/cros_ec_sensors_core.h b/include/linux/iio/common/cros_ec_sensors_core.h
> index ce16445411ac..a1c85ad4df91 100644
> --- a/include/linux/iio/common/cros_ec_sensors_core.h
> +++ b/include/linux/iio/common/cros_ec_sensors_core.h
> @@ -71,6 +71,7 @@ struct cros_ec_sensors_core_state {
>  	enum motionsensor_location loc;
>  
>  	s16 calib[CROS_EC_SENSOR_MAX_AXIS];
> +	s8 sign[CROS_EC_SENSOR_MAX_AXIS];
>  
>  	u8 samples[CROS_EC_SAMPLE_SIZE];
>