[PATCH v7 2/3] clk: introduce the common clock framework

Saravana Kannan skannan at codeaurora.org
Fri Mar 23 17:51:20 EDT 2012


On 03/23/2012 02:39 PM, Turquette, Mike wrote:
> On Fri, Mar 23, 2012 at 2:33 PM, Saravana Kannan<skannan at codeaurora.org>  wrote:
>> On 03/20/2012 08:10 PM, Saravana Kannan wrote:
>>>
>>> On 03/20/2012 04:53 PM, Turquette, Mike wrote:
>>>>
>>>> It does make me
>>>> wonder if it would be a good idea to pass in the parent rate for
>>>> .set_parent, which is analogous to .set_rate in many ways.
>>>
>>>
>>> I need to think a bit more about this.
>>
>>
>> I was thinking about this. I think the common clock fwk should let the
>> set_parent ops "return" the rate of the clock in addition to passing the
>> rate of the parent in.
>>
>> Say this is a divider clock and some one changes the parent. The cached
>> "rate" of the clock in the clock fwk is no longer correct. So, the clock fwk
>> should also add a "*new_rate" param to set parent ops.
>
> __clk_recalc_rates is called by __clk_reparent which is called by
> clk_set_parent.  __clk_recalc_rates is also called by clk_set_rate.
>
> Does this not handle the old cached clk->rate for you?
>

Yeah, I realized this just after I sent the email. I'm looking at the 
code to see if that's sufficient or not. Will get back soon.

-Saravana

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