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Message-ID: <fa096963-c173-dacc-647f-21a367c772b0@9elements.com>
Date:   Mon, 24 Apr 2023 14:22:17 +0530
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Subject: Re: [PATCH v2 1/2] dt-bindings: regulator: Add support for multiple
 supplies
Content-Language: en-US
To:     Rob Herring <robh@kernel.org>
Cc:     zev@bewilderbeest.net, Liam Girdwood <lgirdwood@gmail.com>,
        Mark Brown <broonie@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        linux-kernel@vger.kernel.org, devicetree@vger.kernel.org
References: <20230420192402.3695265-1-Naresh.Solanki@9elements.com>
 <20230421213659.GA1786000-robh@kernel.org>
From:   Naresh Solanki <naresh.solanki@9elements.com>
In-Reply-To: <20230421213659.GA1786000-robh@kernel.org>
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Hi Rob,

On 22-04-2023 03:06 am, Rob Herring wrote:
> On Thu, Apr 20, 2023 at 09:24:01PM +0200, Naresh Solanki wrote:
>> Add optional DT property 'regulator-supplies' to handle connectors with
>> multiple supplies.
>> If this property is present, it will determine all regulator supplies.
>> Otherwise, the 'vout' supply will be used as a fallback.
>>
>> This change improves support for connector like PCIe connectors on
>> mainboards that can be powered by 12V and 3.3V supplies.
>>
>> Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
>> ...
>> Change in V2:
>> - Added example
>> - Update property type & description.
>> - Improve commit message
>> ---
>>   .../bindings/regulator/regulator-output.yaml  | 21 ++++++++++++++++---
>>   1 file changed, 18 insertions(+), 3 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/regulator/regulator-output.yaml b/Documentation/devicetree/bindings/regulator/regulator-output.yaml
>> index 078b37a1a71a..a9dce26991ff 100644
>> --- a/Documentation/devicetree/bindings/regulator/regulator-output.yaml
>> +++ b/Documentation/devicetree/bindings/regulator/regulator-output.yaml
>> @@ -21,13 +21,22 @@ properties:
>>     compatible:
>>       const: regulator-output
>>   
>> -  vout-supply:
>> +  regulator-supplies:
>> +    $ref: /schemas/types.yaml#/definitions/string-array
>>       description:
>> -      Phandle of the regulator supplying the output.
>> +      Optional property that specifies supply names provided by
>> +      the regulator. Defaults to "vout" if not specified. The
>> +      array contains a list of supply names.
>> +      Each supply name corresponds to a phandle in the
>> +      patternProperties.
>> +
>> +patternProperties:
>> +  ".*-supply":
>> +    description:
>> +      Specifies the phandle for various supplies
> 
> While you say use 'vout-supply' for a single supply, nothing enforces
> that anymore.
> 
>>   
>>   required:
>>     - compatible
>> -  - vout-supply
>>   
>>   additionalProperties: false
>>   
>> @@ -37,3 +46,9 @@ examples:
>>             compatible = "regulator-output";
>>             vout-supply = <&output_reg>;
>>         };
>> +      out2 {
>> +          compatible = "regulator-output";
>> +          regulator-supplies = "sw0", "sw1";
>> +          sw0-supply = <&out2_sw0>;
>> +          sw1-supply = <&out2_sw1>;
> 
> Names in the consumer are relative to the consumer. You appear to be
> naming these by the supplier. Just add vout[0-9]-supply and iterate over
> that name in the driver. Then you don't need "regulator-supplies".
> Really, you never did. You could just find all properties ending in
> "-supply".
Please correct me if I have misunderstood anything
What I understood is:
1. Use 'for_each_property_of_node' & iterate each property,
2. String compare each property name ending with '-supply',
3. If there is match then initialize accordingly.
This way all *-supply property are also included including vout-supply.
This way, regulator-supplies isn't needed.
Shall I go ahead in this way ?

> 
> Rob
Regards,
Naresh