Re: [PATCH v3 4/5] clk: mediatek: Add USB clock support in MT8173 APMIXEDSYS

[Daniel Kurtz <djkurtz@chromium.org>]

On Tue, Jul 14, 2015 at 5:46 PM, James Liao <jamesjj.liao@mediatek.com> wrote:
> Hi Daniel,
>
> On Tue, 2015-07-14 at 11:23 +0800, Daniel Kurtz wrote:
>> On Tue, Jul 14, 2015 at 10:45 AM, James Liao <jamesjj.liao@mediatek.com> wrote:
>> > On Mon, 2015-07-13 at 22:46 +0800, Daniel Kurtz wrote:
>> >> > +static const struct clk_ops mtk_ref2usb_tx_ops = {
>> >> > +       .is_prepared    = mtk_ref2usb_tx_is_prepared,
>> >> > +       .prepare        = mtk_ref2usb_tx_prepare,
>> >> > +       .unprepare      = mtk_ref2usb_tx_unprepare,
>> >> > +};
>> >>
>> >> Burying the implementation of this special "mtk_ref2usb" clock in
>> >> clk-mt8173,c seems a bit awkward.
>> >> Can you please move it to its own file, like mediatek/clk-usb.c?
>> >
>> > Do you mean clk/mediatek/clk-usb.c?
>> >
>> > This clock is a MT8173 specific clock, which may not be reused by other
>> > SoCs. So I think it's not necessary to move it to a separated file.
>>
>> Yes, this is a wrapper for a type of clock.  I think it would be
>> better in its own file, rather than embedded in clk-mt8173.c, which is
>> more about enumerating and initializing the clock tree.
>>
>> Perhaps today it is only used for mt8173, but that may not be the case
>> in the future.
>
> OK, I'll separate it from clk-mt8173.c.
>
> Ref2usb_tx's control register is located in APMIXEDSYS, which contains
> most of PLL controlling. Is this clock suitable to implemented
> mtk-pll.c? Or it's proper to be a separated file such as clk-usb.c?

I think a separate clk-usb.c might be better since the driver is very
different than what is used for the PLLs.

Thanks!
-Dan

> Best regards,
>
> James
>
>