Re: [PATCH v2 12/14] staging: iio: ad7746: Add ABI documentation

[Jonathan Cameron <jic23@kernel.org>]

On Fri, 13 Apr 2018 13:36:49 -0300
Hernán Gonzalez <hernan@vanguardiasur.com.ar> wrote:

> The use cases for this driver don't comply with the current ABI. The
> ad7746 and ad7152 need an external capacitance or voltage reference to
> automatically calibrate themselves which is not the normal use case of
> the calibscale and calibbias ABIs, a new ABI was needed.

I agree with the general aim here.  Would appreciate input from Michael
in particular on these + ideally others!

One comment inline,

Thanks,

Jonathan

> 
> Signed-off-by: Hernán Gonzalez <hernan@vanguardiasur.com.ar>
> ---
>  Documentation/ABI/testing/sysfs-bus-iio-ad7746 | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
>  create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-ad7746
> 
> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-ad7746 b/Documentation/ABI/testing/sysfs-bus-iio-ad7746
> new file mode 100644
> index 0000000..96a41b7
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-bus-iio-ad7746
> @@ -0,0 +1,17 @@
> +What:		/sys/bus/iio/devices/iio:deviceX/in_capacitanceX_calibscale_calibration
> +What:		/sys/bus/iio/devices/iio:deviceX/in_voltage0_calibscale_calibration

Hmm. I wonder if indicating that it causes calibration would be better done by
in_voltage0_calibscale_calibrate

> +KernelVersion:	4.17.0
> +Contact:	linux-iio@vger.kernel.org
> +Description:
> +		Enter gain calibration mode, in which a full-scale
> +		{capacitance, voltage reference} must be connected to the
> +		{capacitance, voltage} input beforehand to automatically
> +		calibrate the device.
> +
> +What:		/sys/bus/iio/devices/iio:deviceX/in_capacitanceX_calibbias_calibration
> +KernelVersion:	4.17.0
> +Contact:	linux-iio@vger.kernel.org
> +Description:
> +		Enter offset calibration mode, in which a zero-scale
> +		capacitance must be connected to the capacitance input
> +		beforehand to automatically calibrate the device.