[RFC 0/2] clk: samsung: add composite clocks

[Rahul Sharma]

On Mon, May 20, 2013 at 7:44 PM, Heiko Stübner <heiko at sntech.de> wrote:
> Am Montag, 20. Mai 2013, 16:17:06 schrieb Rahul Sharma:
>> This patch adds support for composite clocks for samsung SoCs.
>> Many drivers need access to a common clock which support gating
>> and/or muxing and/or rate control operations. For example hdmi
>> which needs to switch between parents and call enable/disable for
>> "sclk_hdmi".
>>
>> This patch set also adds composite clock for exyno5250 hdmi. Based
>> on the review comment, I will extended this to other exynos SoCs
>> clocks files.
>
> I think I remember reading somewhere that the target of the common clock
> framework was to prevent every SoC from introducing their own special clock
> types and instead  create these structures from separate clocks (mux clk +
> gate clk) and not to have every SoC create their own custom clock types.
>
> The Samsung clock drivers at the moment follow this paradigm of combining the
> existing "simple" clocks and only introduce new clock types for the pll
> clocks, that really need special handling.
>
> So it would probably good to keep it this way and define your clocks from
> their individual components, as all the other Samsung clocks currently do.
>

Thanks Heiko, I agree, but I am not trying to introduce a new type here,
instead using the existing generic support for composite clocks for
exynos as well.

These have not been added for Samsung SoCs so far but I do not see any
harm in using them also. With them, drivers do not need to get and configure
each clock component separately. This ensures less and more reasonable
changes in the drivers during migration to CCF.

Please help me understand about the loss when using composite clocks.

regards,
Rahul Sharma

>
> Heiko