Re: [PATCH v4 08/13] Documentation: ABI: add specific icm42600 documentation

[Jonathan Cameron <jic23@kernel.org>]

On Mon, 22 Jun 2020 17:37:24 +0200
Jean-Baptiste Maneyrol <jmaneyrol@invensense.com> wrote:

> Hardware offset available as calibscale sysfs attributes are real
> physical values exprimed in SI units.
> 
> calibscale_available sysfs attributes represents the range of
> acceptable values.
> 
> Signed-off-by: Jean-Baptiste Maneyrol <jmaneyrol@invensense.com>

Hi Jean-Baptiste. 

This is causing us some issues as the ABI docs are now added to the
generated html docs for the kernel.  It's been a while, so I've kind
of forgotten why we have this file.  Was the issue that these are
in SI units as opposed to most calibbias controls which are offsets
applied to the raw analog reading hitting the ADC?

Would you mind if we moved this into the main doc as a note for this
particular device?

i.e. something in sysfs-bus-iio saying

icm42600: Hardware applied calibration offset is in SI units (rad/s or m/s^2 as appropriate)

?

Thanks,

Jonathan
 
> ---
>  .../ABI/testing/sysfs-bus-iio-icm42600        | 20 +++++++++++++++++++
>  1 file changed, 20 insertions(+)
>  create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-icm42600
> 
> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-icm42600 b/Documentation/ABI/testing/sysfs-bus-iio-icm42600
> new file mode 100644
> index 000000000000..0bf1fd4f5bf1
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-bus-iio-icm42600
> @@ -0,0 +1,20 @@
> +What:		/sys/bus/iio/devices/iio:deviceX/in_accel_x_calibbias
> +What:		/sys/bus/iio/devices/iio:deviceX/in_accel_y_calibbias
> +What:		/sys/bus/iio/devices/iio:deviceX/in_accel_z_calibbias
> +What:		/sys/bus/iio/devices/iio:deviceX/in_anglvel_x_calibbias
> +What:		/sys/bus/iio/devices/iio:deviceX/in_anglvel_y_calibbias
> +What:		/sys/bus/iio/devices/iio:deviceX/in_anglvel_z_calibbias
> +KernelVersion:  5.8
> +Contact:        linux-iio@vger.kernel.org
> +Description:
> +		Hardware applied calibration offset (assumed to fix production
> +		inaccuracies). Values represent a real physical offset expressed
> +		in SI units (m/s^2 for accelerometer and rad/s for gyroscope).
> +
> +What:		/sys/bus/iio/devices/iio:deviceX/in_accel_calibbias_available
> +What:		/sys/bus/iio/devices/iio:deviceX/in_anglvel_calibbias_available
> +KernelVersion:  5.8
> +Contact:        linux-iio@vger.kernel.org
> +Description:
> +		Range of available values for hardware offset. Values in SI
> +		units (m/s^2 for accelerometer and rad/s for gyroscope).