Re: [PATCH v10 3/5] dt-bindings: clock: meson: add A1 PLL and Peripherals clkcs bindings

From: Krzysztof Kozlowski
Date: Tue Mar 14 2023 - 12:37:47 EST


On 14/03/2023 16:56, Dmitry Rokosov wrote:
> On Tue, Mar 14, 2023 at 04:40:19PM +0100, neil.armstrong@xxxxxxxxxx wrote:
>> On 14/03/2023 16:37, Krzysztof Kozlowski wrote:
>>> On 14/03/2023 16:33, neil.armstrong@xxxxxxxxxx wrote:
>>>>> There are many ways - depend on your driver. For example like this:
>>>>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/clk/samsung/clk-exynos5420.c#n975
>>>>>
>>>>> The first argument is the clock ID (or ignore).
>>>>>
>>>>> BTW, quite likely the problem is generic to all Meson clock drivers.
>>>>
>>>> This issue about "public" non-continuous defined was already discussed at https://lore.kernel.org/all/c088e01c-0714-82be-8347-6140daf56640@xxxxxxxxxx/
>>>>
>>>> I don't see what's different with this one.
>>>
>>> So you are aware that all undocumented clock IDs are still allowed to
>>> use in DTS and they are ABI? Changing them will be an ABI break.
>>
>> Yes of course.
>>
>> Neil
>>
>>>
>>> Best regards,
>>> Krzysztof
>>>
>>
>
> Sorry, guys, I'm little bit confused.
> In the discussion pointed by Neil not-by-one-increment ID with public and
> private parts are acked by Krzysztof due to explicit explanation in the
> gxbb header. Have I to comment out my situation and stay it as is?

I did not NAK your solution here. I just pointed my usual remarks that
it has certain outcome and minuses (undocumented ABI). But it is OK.

>
> BTW, I think changing IDs value would not affect logic, because
> it's not connected to driver logic 'by values', but 'by constants

You cannot change the IDs, neither their values nor the names (with
exceptions). IDs - so the numbers - are ABI.

"Constant names" - I assume you mean the names of defines - do not exist
after preprocessing, so also not really relevant here...

> names'. We can expose/hide anything from device tree bindings, it will
> not change the clk driver logic.


Best regards,
Krzysztof