Re: [PATCH v3 3/7] dt-bindings: mfd: add binding for Apple Mac System Management Controller

[Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>]

On 10/11/2022 12:48, Russell King (Oracle) wrote:
> On Wed, Nov 09, 2022 at 04:17:23PM -0600, Rob Herring wrote:
>> On Tue, Nov 08, 2022 at 10:22:31PM +0000, Russell King (Oracle) wrote:
>>> On Tue, Nov 08, 2022 at 09:55:58PM +0100, Krzysztof Kozlowski wrote:
>>>> On 08/11/2022 17:33, Russell King (Oracle) wrote:
>>>>> Add a DT binding for the Apple Mac System Management Controller.
>>>>
>>>> Drop the second, redundant "binding" from subject. It's already in prefix.
>>>
>>> Yet another thing that's been there from the start... how many more
>>> things are you going to pick up in subsequent versions of the patch?
>>> When does this stop?
>>>
>>> In any case, taking your comment literally,
>>>
>>> "dt-bindings: mfd: add for Apple Mac System Management Controller"
>>>
>>> makes no sense, so presumably you want something more than that.
>>>
>>> In any case, I see several recent cases already merged which follow
>>> the pattern that I've used and that you've reviewed.
>>>
>>>>> Signed-off-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>
>>>>> ---
>>>>>  .../devicetree/bindings/mfd/apple,smc.yaml    | 67 +++++++++++++++++++
>>>>>  1 file changed, 67 insertions(+)
>>>>>  create mode 100644 Documentation/devicetree/bindings/mfd/apple,smc.yaml
>>>>>
>>>>> diff --git a/Documentation/devicetree/bindings/mfd/apple,smc.yaml b/Documentation/devicetree/bindings/mfd/apple,smc.yaml
>>>>> new file mode 100644
>>>>> index 000000000000..014eba5a1bbc
>>>>> --- /dev/null
>>>>> +++ b/Documentation/devicetree/bindings/mfd/apple,smc.yaml
>>>>> @@ -0,0 +1,67 @@
>>>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>>>>> +%YAML 1.2
>>>>> +---
>>>>> +$id: http://devicetree.org/schemas/mfd/apple,smc.yaml#
>>>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>>>> +
>>>>> +title: Apple Mac System Management Controller
>>>>> +
>>>>> +maintainers:
>>>>> +  - Hector Martin <marcan@xxxxxxxxx>
>>>>> +
>>>>> +description:
>>>>> +  Apple Mac System Management Controller implements various functions
>>>>> +  such as GPIO, RTC, power, reboot.
>>>>> +
>>>>> +properties:
>>>>> +  compatible:
>>>>> +    items:
>>>>> +      - enum:
>>>>> +          - apple,t6000-smc
>>>>> +          - apple,t8103-smc
>>>>> +          - apple,t8112-smc
>>>>> +      - const: apple,smc
>>>>> +
>>>>> +  reg:
>>>>> +    items:
>>>>> +      - description: SMC area
>>>>> +      - description: SRAM area
>>>>> +
>>>>> +  reg-names:
>>>>> +    items:
>>>>> +      - const: smc
>>>>> +      - const: sram
>>>>> +
>>>>> +  mboxes:
>>>>> +    maxItems: 1
>>>>> +
>>>>> +  gpio:
>>>>> +    $ref: /schemas/gpio/gpio-macsmc.yaml
>>>>
>>>> So this depends on other patch, so:
>>>> 1. You need mention the dependency in cover letter (nothing there),
>>>> 2. Re-order patches.
>>>>
>>>> The GPIO cannot go separate tree and this must be explicitly communicated.
>>>
>>> Sigh, getting an order that is sensible is really bloody difficult.
>>
>> It's not. Sub-devices before the MFD. The only time that doesn't work is 
>> when the sub-devices put the parent MFD in their example. The solution 
>> there is don't do that. Just 1 complete example in the MFD schema and no 
>> examples in the sub-devices.
> 
> Meanwhile, I was told by Krzysztof that DT schemas must always have an
> example. So, different person, different story.

Hm, where do you see a message I told you to always have examples? Maybe
in some discussion I mentioned that examples are desired, but not
always. There is no point in having example in MFD child device schema
if it is already part of the parent MFD binding, where it is actually
required for complete picture.

Best regards,
Krzysztof