Re: [PATCH 1/8] dt-bindings: mfd: stm32-lptimer: add support for stm32mp25

[Fabrice Gasnier]

On 2/25/25 13:02, Krzysztof Kozlowski wrote:
> On Mon, Feb 24, 2025 at 07:01:43PM +0100, Fabrice Gasnier wrote:
>>    pwm:
>>      type: object
>>      additionalProperties: false
>>  
>>      properties:
>>        compatible:
>> -        const: st,stm32-pwm-lp
>> +        enum:
>> +          - st,stm32-pwm-lp
>> +          - st,stm32mp25-pwm-lp
>>  
>>        "#pwm-cells":
>>          const: 3
>> @@ -69,7 +76,9 @@ properties:
>>  
>>      properties:
>>        compatible:
>> -        const: st,stm32-lptimer-counter
>> +        enum:
>> +          - st,stm32-lptimer-counter
>> +          - st,stm32mp25-lptimer-counter
> 
> Driver changes suggest many of these are compatible. Why isn't this expressed?

Hi Krzysztof,

The Low Power Timer (LPTIM) hardware isn't fully backward compatible.

At driver level, as indicated in the cover-letter, same feature list as
on STM32MP1x is supported currently. This is probably what makes it look
like it's compatible, but it's not fully compatible.

The hardware controller is a bit different. Some registers/bits has been
revisited among other things. This is the purpose for these new compatibles.

Please find driver-related answers each driver part.

Best regards,
Fabrice

> 
> Best regards,
> Krzysztof
>