Re: [PATCH v2 11/14] staging: iio: ad7746: Add devicetree bindings documentation

["Hernán Gonzalez" <hernan@vanguardiasur.com.ar>]

On Sun, Apr 15, 2018 at 12:37 PM, Jonathan Cameron <jic23@kernel.org> wrote:
> On Fri, 13 Apr 2018 13:36:48 -0300
> Hernán Gonzalez <hernan@vanguardiasur.com.ar> wrote:
>
>> Cc: Rob Herring <robh+dt@kernel.org>
>> Cc: Mark Rutland <mark.rutland@arm.com>
>> Cc: devicetree@vger.kernel.org
>> Signed-off-by: Hernán Gonzalez <hernan@vanguardiasur.com.ar>
> A few comments inline.
>
> Thanks,
>
> Jonathan
>
>> ---
>>  .../devicetree/bindings/staging/iio/cdc/ad7746.txt | 34 ++++++++++++++++++++++
>>  1 file changed, 34 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/staging/iio/cdc/ad7746.txt
>>
>> diff --git a/Documentation/devicetree/bindings/staging/iio/cdc/ad7746.txt b/Documentation/devicetree/bindings/staging/iio/cdc/ad7746.txt
>> new file mode 100644
>> index 0000000..7740f05
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/staging/iio/cdc/ad7746.txt
>> @@ -0,0 +1,34 @@
>> +Analog Devices AD7746/5/7 capacitive sensor driver
>> +
>> +Required properties:
>> +     - compatible: Should be one of
>> +             * "adi,ad7745"
>> +             * "adi,ad7746"
>> +       * "adi,ad7747"
>> +     - reg: The 7-bits long I2c address of the device
>> +
>> +Optional properties:
>> +     - adi,exclvl: This property defines the excitation voltage level for the
>> +    capacitance to be measured. Possible values are:
>> +      * 0 = +-VDD/8
>> +      * 1 = +-VDD/4
>> +      * 2 = +-VDD * 3/8
>> +      * 3 = +-VDD/2 (Default)
>> +     - adi,nexca_en: Invert excitation output A.
>
> The naming is rather odd.  Why _en?
>

Just sticking to the original pdata naming. I'll rename it on next series.

>> +     - adi,nexcb_en: Invert excitation output B.
>> +
>> +Example:
>> +Here exclvl would be 1 (VDD/4), Excitation pin A would be inverted and
>> +Excitation pin B would NOT be inverted.
>> +
>> +i2c2 {
>> +
>> +      < . . . >
> What does this spacer add to the example?
> Sure, there can be other devices, but no need to illustrate that here.
>
>> +
>> +      ad7746: ad7746@60 {
>> +              compatible = "ad7746";
>> +              reg = <0x60>;
>> +              adi,exclvl = <1>;
>> +              adi,nexca_en;
>> +      };
>> +};
>