Re: [PATCH 1/2] dt-bindings: mfd: syscon: Disallow simple-bus with syscon

[Krzysztof Kozlowski <krzk@kernel.org>]

On 04/06/2026 23:40, Rob Herring (Arm) wrote:
> 
> On Sun, 31 May 2026 13:04:05 +0200, Krzysztof Kozlowski wrote:
>> "syscon" is a system controller with registers having their own
>> functions, thus not really a trivial MMIO simple bus.  "simple-bus" on
>> the other hand is just a bus on which multiple devices sit and the
>> "simple" means no functions are allowed here.
>>
>> Combination of both "syscon" and "simple-bus" is abuse of DT for easier
>> instantiating of Linux device drivers so add a schema to disallow that.
>>
>> Unfortunately there are a few old cases of that patterns, so add
>> exceptions:
>>
>> 1. "cznic,turris1x-cpld" and "img,pistachio-cr-periph" are already used
>>    in upstream DTS.
>>
>> 2. TI has several DTSI with a child of SCM device (e.g. "ti,am3-scm")
>>    using "syscon" and "simple-bus" but without a dedicated compatible
>>    documented anywhere.  Add new compatibles for such cases.
>>
>> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
>> ---
>>  .../bindings/mfd/syscon-common.yaml           | 27 +++++++++++++++++--
>>  1 file changed, 25 insertions(+), 2 deletions(-)
>>
> 
> Acked-by: Rob Herring (Arm) <robh@kernel.org>

Thanks for ack, but this is partial patch on top of my earlier work
which I forgot to squash here. I will send a v2 without the ack.

Best regards,
Krzysztof