[v2,1/2] dt-bindings: regulator: Add support for multiple supplies

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(-)


base-commit: 43c75e470e5b56a992acb08474810e6822f0989c

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".

Rob

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

Hi Rob,

On 24-04-2023 02:22 pm, Naresh Solanki wrote:
> 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 ?
I wanted to follow up on our previous discussion regarding the naming of 
properties in the consumer. Based on your feedback, I believe that I 
should use 'for_each_property_of_node' to iterate over each property and 
then string compare each property name to find those that end with 
'-supply'. This way, all *-supply properties will be included, including 
vout-supply, and the 'regulator-supplies' won't be needed.
Can you please confirm if my understanding is correct?
Thank you.
> 
>>
>> Rob
> Regards,
> Naresh