display: bcm2835-dpi: warning about #address-cells', '#size-cells'

display: bcm2835-dpi: warning about #address-cells', '#size-cells'

[Stefan Wahren]

Hi,

recently i noticed the following warning during "make dtbs_check"

arch/arm/boot/dts/bcm2835-rpi-b.dtb: dpi@7e208000: '#address-cells', 
'#size-cells' do not match any of the regexes: 'pinctrl-[0-9]+'

During conversion to DT schema 094536003e06 "dt-bindings: display: 
Convert VC4 bindings to schemas" the properties has been dropped from 
the example.

But i'm not sure how to fix this properly (drop them from the 
bcm283x.dtsi file or add the properties to brcm,bcm2835-dpi.yaml).

Best regards

Re: display: bcm2835-dpi: warning about #address-cells', '#size-cells'

[Maxime Ripard]

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On Mon, Jun 06, 2022 at 01:40:19PM +0200, Stefan Wahren wrote:
> Hi,
> 
> recently i noticed the following warning during "make dtbs_check"
> 
> arch/arm/boot/dts/bcm2835-rpi-b.dtb: dpi@7e208000: '#address-cells',
> '#size-cells' do not match any of the regexes: 'pinctrl-[0-9]+'
> 
> During conversion to DT schema 094536003e06 "dt-bindings: display: Convert
> VC4 bindings to schemas" the properties has been dropped from the example.
> 
> But i'm not sure how to fix this properly (drop them from the bcm283x.dtsi
> file or add the properties to brcm,bcm2835-dpi.yaml).

So #address-cells and #size-cells are used to get the children register
address and size.

However, for DPI, it's not clear what the child node is going to be in
the first place. The only one that stands out is the port node, but
there's a single one. So we don't need a reg property to differentiate
between multiple ports, and thus we don't need #address-cells or
#size-cells.

The proper fix would be to remove them from the bcm283x device tree.

Maxime

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Re: display: bcm2835-dpi: warning about #address-cells', '#size-cells'

[Stefan Wahren]

Hi Maxime,

Am 06.06.22 um 15:47 schrieb Maxime Ripard:
> On Mon, Jun 06, 2022 at 01:40:19PM +0200, Stefan Wahren wrote:
>> Hi,
>>
>> recently i noticed the following warning during "make dtbs_check"
>>
>> arch/arm/boot/dts/bcm2835-rpi-b.dtb: dpi@7e208000: '#address-cells',
>> '#size-cells' do not match any of the regexes: 'pinctrl-[0-9]+'
>>
>> During conversion to DT schema 094536003e06 "dt-bindings: display: Convert
>> VC4 bindings to schemas" the properties has been dropped from the example.
>>
>> But i'm not sure how to fix this properly (drop them from the bcm283x.dtsi
>> file or add the properties to brcm,bcm2835-dpi.yaml).
> So #address-cells and #size-cells are used to get the children register
> address and size.
>
> However, for DPI, it's not clear what the child node is going to be in
> the first place. The only one that stands out is the port node, but
> there's a single one. So we don't need a reg property to differentiate
> between multiple ports, and thus we don't need #address-cells or
> #size-cells.
>
> The proper fix would be to remove them from the bcm283x device tree.
thanks. I will send a patch soon.
>
> Maxime