Re: [PATCH] ARM: mvebu: Fix of_clk_get() call in a non sleeping context

[Gregory CLEMENT <gregory.clement@free-electrons.com>]

Hi Russell King,
 
 On mar., mars 08 2016, Russell King - ARM Linux <linux@arm.linux.org.uk> wrote:

> On Tue, Mar 08, 2016 at 05:38:11PM +0100, Gregory CLEMENT wrote:
>> And from clk_enable comment we have:
>> ""
>> clk_enable must not sleep, which differentiates it from clk_prepare.  In a
>> simple case, clk_enable can be used instead of clk_prepare to ungate a clk
>> if the operation will never sleep.
>> ""
>> 
>> Moreoever for me the "must" was to insist to the order of the call no to
>> the fact that both must be called.
>
> As the author of the clk API, the idea here is that clk_prepare()
> should always be called _before_ clk_enable() for any clock: in
> other words, getting a clock and then calling clk_enable() on it
> is not legal.
>
> CCF presently enforces this - clk_enable() without a preceding
> clk_prepare() will return -ESHUTDOWN.

Thanks for the clarification, I will work on a alternative solutioin.

Gregory

>
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-- 
Gregory Clement, Free Electrons
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