[PATCH 3/4] ARM: S5PC110: add common FIMC setup code

Marek Szyprowski m.szyprowski at samsung.com
Mon Sep 6 06:21:50 EDT 2010


Hello,

On 2010-09-06 18:17, Jassi Brar wrote:

>> I'm thinking of making the parent clock an argument to the
>> s5pv210_fimc_setup_clks().
> Yes, that's better since the relevant clock is managed by the CMU

What do you mean by the CMU? This function is intended to be called from 
board startup code.

>> I really don't like the idea of passing clock name through the platform data
>> and letting driver to mess with clock's parents.
> In case of SPI the clock mux and scalar is present _within_ the SPI
> controller and having to touch SPI regs from outside the driver isn't
> what I prefer.

I know. It is the same case as with SDHCI and UART controllers. I have 
an idea how to solve this in a bit more cleaner way. I hope to post a 
proposition soon.

>> Machine startup code is the
>> last place where such things should be changed.
> Until I am enlightened, I'd like to think otherwise.
> I think the board designer would already have thought out the clock sourcing
> hierarchy. Setting appropriate parents once at boot-time and having drivers
> not worry about it, should be better.

Definitely, but in our case kernel the default fimc_sclk parent points 
to non-existing clock.

Best regards
-- 
Marek Szyprowski
Samsung Poland R&D Center



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