Re: [PATCH 1/3] arm64: dts: qcom: sdm630: fix UART1 pin bias

[Krzysztof Kozlowski]

On 03/10/2022 17:29, Doug Anderson wrote:
> Hi,
> 
> On Sat, Oct 1, 2022 at 2:58 AM Krzysztof Kozlowski
> <krzysztof.kozlowski@xxxxxxxxxx> wrote:
>>
>>> I would also note that convention on Qualcomm SoCs that I've worked on
>>> was that bias shouldn't be specified in the SoC dtsi file and should
>>> be left to board files. This is talked a bit about in a previous email
>>> thread [1].
>>
>> Uh, that makes a lot of sense. It is almost always a property of a board.
> 
> Right, though it can make sense to have a "default" in the SoC
> sometimes. 

If the default is safe, then could be. But it is still causing a risk of
developer just forgetting to configure the configs for his board.
Bringup of DTS should be a conscious decision, not just "copy and hope
it works", therefore recommendation is to configure per-board properties
in board. Even if it means duplication. The same was for board-provided
clocks or aliases.

> For instance, for i2c you almost always want external
> pullups so you can tune them to the speed/trace lengths. Thus having a
> default in the SoC file to disable i2c pullups would make a lot of
> sense. The problem is the ugly / non-obvious "delete-property" we need
> to put in the board.dts file if we ever need to override the SoC's
> pull. :(

Which might not help in reducing amount of code...



Best regards,
Krzysztof