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

[Krzysztof Kozlowski]

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@xxxxxxxxxx> 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.

> 
>>> 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:


Best regards,
Krzysztof