Re: [PATCH v2 1/4] dt-bindings: iio: adc: ad7192: Add properties - Alisa-Dariana Roman

From: Alisa-Dariana Roman <alisadariana@gmail.com>
To: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
	Alisa-Dariana Roman <alisa.roman@analog.com>,
	Michael Hennerich <michael.hennerich@analog.com>
Cc: linux-iio@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Lars-Peter Clausen <lars@metafoo.de>,
	Alexandru Tachici <alexandru.tachici@analog.com>,
	Jonathan Cameron <jic23@kernel.org>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Conor Dooley <conor+dt@kernel.org>
Subject: Re: [PATCH v2 1/4] dt-bindings: iio: adc: ad7192: Add properties
Date: Fri, 2 Feb 2024 16:14:28 +0200	[thread overview]
Message-ID: <09cc2ecb-b73f-495a-9196-dbb4899f4c85@gmail.com> (raw)
In-Reply-To: <c6ca5a25-2d41-4a46-95a5-eb994c4cf529@linaro.org>

On 14.11.2023 22:29, Krzysztof Kozlowski wrote:
> On 14/11/2023 21:05, Alisa-Dariana Roman wrote:
>> Document properties used for clock configuration.
> 
> Some background here is missing - otherwise it looks like you are adding
> new properties...
> 
>>
>> Signed-off-by: Alisa-Dariana Roman <alisa.roman@analog.com>
>> ---
>>   .../devicetree/bindings/iio/adc/adi,ad7192.yaml        | 10 ++++++++++
>>   1 file changed, 10 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7192.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7192.yaml
>> index 16def2985ab4..9b59d6eea368 100644
>> --- a/Documentation/devicetree/bindings/iio/adc/adi,ad7192.yaml
>> +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7192.yaml
>> @@ -80,6 +80,16 @@ properties:
>>         and when chop is disabled.
>>       type: boolean
>>   
>> +  adi,clock-xtal:
>> +    description: |
>> +      External crystal connected from MCLK1 to MCLK2.
> 
> And this should be input clock.
> 
>> +    type: boolean
>> +
>> +  adi,int-clock-output-enable:
>> +    description: |
>> +      Internal 4.92 MHz clock available on MCLK2 pin.
>> +    type: boolean
> 
> This should be clock-cells and clock provider.
> 
> Unless you are just documenting already used interface which you do not
> want to break...
> 
>> +
>>     bipolar:
>>       description: see Documentation/devicetree/bindings/iio/adc/adc.yaml
>>       type: boolean
> 
> Best regards,
> Krzysztof
> 

Thank you very much for the feedback!

If I understand correctly, there is already an input clock in the bindings:
```
   clocks:
     maxItems: 1
     description: phandle to the master clock (mclk)

   clock-names:
     items:
       - const: mclk
```

What I wanted to accomplish with this patch is to document these boolean 
properties (from the ad7192 driver code):
```
	/* use internal clock */
	if (!st->mclk) {
		if (device_property_read_bool(dev, "adi,int-clock-output-enable"))
			clock_sel = AD7192_CLK_INT_CO;
	} else {
		if (device_property_read_bool(dev, "adi,clock-xtal"))
			clock_sel = AD7192_CLK_EXT_MCLK1_2;
		else
			clock_sel = AD7192_CLK_EXT_MCLK2;
	}
```

Please let me know how to proceed further!

Kind regards,
Alisa-Dariana Roman