Re: [PATCH v3 0/4] clk: st: New always-on clock domain

From: Robert Jarzmik
Date: Mon Mar 02 2015 - 06:29:23 EST


Lee Jones <lee.jones@xxxxxxxxxx> writes:

> On Sat, 28 Feb 2015, Robert Jarzmik wrote:
>
>> Lee Jones <lee.jones@xxxxxxxxxx> writes:
>> it doesn't specify which usecase is not covered by CLK_IGNORE_UNUSED, it
>> says, up to my understanding, that is it another way to have to
>> CLK_IGNORE_UNUSED flag applied.
>
> Well that is exactly what we're doing. Is there an issue with that?
>
> This is a way to do it at a platform level. It means we can support
> multiple platforms where clocksources have been switched around
> without writing new driver code in drivers/clk/st.
>
> If you have something else in mind, let me know.
>
>> 2) I still fail to see why this is necessary
>> IOW why declaring the mandatory always-on clocks with the proper flag should
>> be augmented with a new clock list. Isn't the existing flag the generic way
>> ?
>
> I'm not sure what you mean by this, would you be able to expland a
> little?
>
>> I might not understand the real motivation behind that of course, that's why I'm
>> asking.
>
> Please bear in mind that we don't supply our clocks statically. All
> of the information is extracted from DT, so if the always-on
> information does reside in there, where do you propose it comes from?

I thought the standard clock binding provided a way to set this flag. Now I
crosschecked the binding, it doesn't ...

My point was I didn't want the flag to be settable from 2 different places,
where consistency was to be kept across different device-tree leafs.

> We could just write this code inside our own driver and apply the
> CLK_IGNORE_UNUSED at a local level, but that's not the generic
> solution I am searching for.

All right, I'm convinced now I undertand the flag was not settable from
devicetree binding before this patchset.

You can add to patch 3/4 :
Reviewed-by: Robert Jarzmik <robert.jarzmik@xxxxxxx>

--
Robert
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