Re: [PATCH v10 1/7] dt-bindings: media: qcom,x1e80100-camss: Add simple-mfd compatible
From: Krzysztof Kozlowski
Date: Tue Mar 17 2026 - 12:01:45 EST
On 17/03/2026 16:51, Krzysztof Kozlowski wrote:
> On 16/03/2026 13:01, Bryan O'Donoghue wrote:
>> On 16/03/2026 07:29, Krzysztof Kozlowski wrote:
>>> On Mon, Mar 16, 2026 at 01:02:01AM +0000, Bryan O'Donoghue wrote:
>>>> Add "simple-mfd" as a second compatible string to allow child nodes
>>>> within the CAMSS block to probe as individual platform devices.
>>>>
>>>> Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx>
>>>> ---
>>>> Documentation/devicetree/bindings/media/qcom,x1e80100-camss.yaml | 8 ++++++--
>>>> 1 file changed, 6 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/media/qcom,x1e80100-camss.yaml b/Documentation/devicetree/bindings/media/qcom,x1e80100-camss.yaml
>>>> index 2d1662ef522b7..b5654ef71bd89 100644
>>>> --- a/Documentation/devicetree/bindings/media/qcom,x1e80100-camss.yaml
>>>> +++ b/Documentation/devicetree/bindings/media/qcom,x1e80100-camss.yaml
>>>> @@ -14,7 +14,11 @@ description:
>>>>
>>>> properties:
>>>> compatible:
>>>> - const: qcom,x1e80100-camss
>>>> + oneOf:
>>>> + - const: qcom,x1e80100-camss
>>>> + - items:
>>>> + - const: qcom,x1e80100-camss
>>>> + - const: simple-mfd
>>>>
>>>> reg:
>>>> maxItems: 17
>>>> @@ -191,7 +195,7 @@ examples:
>>>> #size-cells = <2>;
>>>>
>>>> camss: isp@acb7000 {
>>>> - compatible = "qcom,x1e80100-camss";
>>>> + compatible = "qcom,x1e80100-camss", "simple-mfd";
>>>
>>> You do not have any children here. And if you checked the DTS, you
>>> would see this does not work.
>>>
>>> Please post complete example and bindings.
>>>
>>> I suspect that after posting complete picture we will see this is not a
>>> simple-mfd device (child depends on parent).
>>>
>>> Best regards,
>>> Krzysztof
>>>
>>
>> This is it:
>>
>> https://lore.kernel.org/r/20260316-x1e-camss-csi2-phy-dtsi-v2-3-859f3fa55790@xxxxxxxxxx
>
> That's a DTS branch.
>
> This commit is simply incomplete and noop. Adding simple-mfd without
> child makes no sense and no benefits.
>
> It's like adding a local variable in C code without any read/assignment.
>
>>
>> Just broke up the series so that drivers/bindings could go through
>> linux-media and the dtsi stuff through Bjorn.
>>
>> I actually got the idea from:
>>
>> commit fe6a952b567f6a771d087d2e969914f31574d6ab
>> Author: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
>> Date: Fri Jan 27 20:40:50 2023 +0100
>
> If you refer to my commits, at least read them. Do you see children
> there? Yes. You have none.
>
> Plus trying to get 13 year old legacy device without dtbs_check warnings
> is different thing than correcting a recently introduced bindings.
> Terrible example to take... And if you find example from 20 years ago,
> it will be even worse.
>
One more thing, that commit was still correct because it fulfilled the
simple-mfd requirement of lack of dependency on the parent. I do not
believe your code fulfills it. I am pretty sure it does not.
See 2023 and 2022 talks, how to get your schema accepted in less than 10
iterations.
Or please read writing bindings which *describes exactly that case*.
We have it documented, I was speaking about this more than once.
I also mentioned so many times - do not make random changes, just
because you found commit doing something similar. You were cc-ed even on
such remarks from my side, like discussion with Jorge were irrelevant
work was used as arguments, instead of providing actual technical arguments.
https://lore.kernel.org/all/0d381ad0-85d4-43de-a050-3b9ed03bf5d8@xxxxxxxxxx/
Don't ever reference some irrelevant commits in the past just because
something looks similar. It makes no sense. Devices are completely
different.
Best regards,
Krzysztof