[PATCH 04/14] dt-bindings: pinctrl: stm32: add RSVD mux function

[Krzysztof Kozlowski]

On 23/10/2024 10:56, Antonio Borneo wrote:
> On Wed, 2024-10-23 at 10:47 +0200, Krzysztof Kozlowski wrote:
>> On Tue, Oct 22, 2024 at 05:56:48PM +0200, Antonio Borneo wrote:
>>> From: Fabien Dessenne <fabien.dessenne at foss.st.com>
>>>
>>> Document the RSVD (Reserved) mux function, used to reserve pins
>>> for a coprocessor not running Linux.
>>>
>>> Signed-off-by: Fabien Dessenne <fabien.dessenne at foss.st.com>
>>> Signed-off-by: Antonio Borneo <antonio.borneo at foss.st.com>
>>> ---
>>>  .../devicetree/bindings/pinctrl/st,stm32-pinctrl.yaml     | 8 ++++++++
>>>  include/dt-bindings/pinctrl/stm32-pinfunc.h               | 1 +
>>>  2 files changed, 9 insertions(+)
>>>
>>
>> BTW, which *existing* SoCs use it? Aren't you adding it for the new
>> platform?
>>
> 
> This is already used in ST downstream kernel for STM32MP15x
> In this example
> https://github.com/STMicroelectronics/linux/blob/v6.1-stm32mp/arch/arm/boot/dts/stm32mp157f-dk2-m4-examples.dts#L112
> 
> the GPIOs for LED and for PWM are assigned to the Cortex-M4 and Linux (on Cortex-A7) is not supposed to touch them.

I wasn't clear. Which upstream uses it? We really could not care less
about downstream vendor code.

Best regards,
Krzysztof