[PATCH] clk: Dont return error when assigned-clocks is empty or missing

[Michal Simek]

On 7/11/23 16:28, Sean Anderson wrote:
> On 7/11/23 10:20, Michal Simek wrote:
>> Hi Sean,
>>
>> On 7/11/23 15:40, Sean Anderson wrote:
>>> On 7/11/23 05:51, Ashok Reddy Soma wrote:
>>>> There is a chance that assigned-clock-rates is given and assigned-clocks
>>>> could be empty. Dont return error in that case, because the probe of the
>>>> corresponding driver will not be called at all if this fails.
>>>> Better to continue to look for it and return 0.
>>>
>>> No, this is an error in the device tree. assigned-clock-rates depends on
>>> assigned-clocks, so you must provide the latter if the former is present.
>>
>> We were also checking it and in the Linux kernel it is handle like this.
>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/clk/clk-conf.c#n95
>>
>> It means you can have rate assigned but not assigned-clocks property.
>>
>> And yes in working case both should be present to work properly.
> 
> What is the use-case for this? It will not pass schema checking [1] anyway.
> 
> --Sean
> 
> [1] 
> https://github.com/devicetree-org/dt-schema/blob/main/dtschema/schemas/clock/clock.yaml

If you check your DT against schema. No doubt how correct behavior should be.

It is just aligning behavior with Linux kernel if user messes up DT.

Thanks,
Michal