Re: [PATCH] dt-bindings: leds: Describe optional 'reg' property used for Qualcomm LPG nodes

[Bhupesh Sharma <bhupesh.sharma@linaro.org>]

On 8/9/22 12:21 PM, Krzysztof Kozlowski wrote:
> On 08/08/2022 21:44, Bjorn Andersson wrote:
>> On Thu 21 Jul 13:19 PDT 2022, Dmitry Baryshkov wrote:
>>
>>> On Thu, 21 Jul 2022 at 22:55, Bhupesh Sharma <bhupesh.sharma@linaro.org> wrote:
>>>>
>>>> As Bjorn noted in [1], it is useful to describe the optional
>>>> 'reg' property for Qualcomm LPG nodes as it is used in
>>>> some Qualcomm dts files.
>>>
>>> I don't think this is correct. LPG block maps to several regions, so
>>> using just one of them in reg doesn't look correct.
>>>
>>
>> I agree, but I also like the uniformity of having unit addresses for the
>> devices on the spmi buses.
> 
> regulators also do not have reg, so I guess consistency is already gone.
> 
> I vote here to reflect the real hardware/device which means:
> 1. IIUC, the design of entire SPMI bindings and its implementation is
> around parent device sitting on SPMI bus and children using its
> regmap/io space.
> 2. The children are not really re-usable for different cases/devices
> (e.g. standalone WLED or LPG, outside of PMIC).
> 3. This means entire design is tightly coupled and LPG (or wled,
> regulators) bindings describe the piece of PMIC, thus I find appropriate
> skipping "reg".
> 4. If we want to keep the "reg", then it should rather reflect reality,
> so if Dmitry said - multiple items for separate IO address ranges.

Ok, so I think the majority opinion is to skip 'reg' from the 
devicetree-binding. Lets stick to that.

>>
>>>> This fixes the following 'make dtbs_check' error reported for
>>>> pm8350c & sc8280xp pwm nodes:
>>>>
>>>> arch/arm64/boot/dts/qcom/sc7280-herobrine-herobrine-r1.dtb:
>>>>   pwm@e800: 'reg' does not match any of the regexes:
>>>>   '^led@[0-9a-f]$', 'pinctrl-[0-9]+'
>>>
>>> I'd prefer to follow the existing schema and to drop the region from
>>> those files.
>>>
>>
>> I'm fine either way, but we have more of these nodes, so I would like to
>> hear from the DT maintainers on the direction to take. All nodes on the
>> spmi bus has an (at least one) address, so it would be accurate to state
>> this in the node.
>>
>> It does however not seem like devicetree@, nor Krzysztof is Cc'ed on
>> this patch, so I've added them...
>>
> 
> Anyway this patch has to be resent to properly reach DT patchwork.
> 
> Bhupesh,
> 
> Please use scripts/get_maintainer.pl to Cc relevant folks and mailing
> lists. While resending, add appropriate device prefix to subject, so:
> dt-bindings: leds: qcom-lpg:

Sure, will send v2 accordingly.

Thanks.