[RFC V1 2/8] clk: pass parent rate if recalc_rate is NULL

[Richard Zhao]

On Wed, Nov 23, 2011 at 02:17:50PM -0800, Mike Turquette wrote:
> On Wed, Nov 23, 2011 at 3:12 AM, Richard Zhao <richard.zhao at linaro.org> wrote:
> > Signed-off-by: Richard Zhao <richard.zhao at linaro.org>
> > ---
> >  drivers/clk/clk.c |    4 ++++
> >  1 files changed, 4 insertions(+), 0 deletions(-)
> >
> > diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
> > index ed557c9..2d8422f 100644
> > --- a/drivers/clk/clk.c
> > +++ b/drivers/clk/clk.c
> > @@ -256,6 +256,8 @@ static void clk_recalc_rates(struct clk *clk)
> >
> >        if (clk->ops->recalc_rate)
> >                clk->rate = clk->ops->recalc_rate(clk);
> > +       else if (clk->parent)
> > +               clk->rate = clk->parent->rate;
> 
> My code at Linaro Connect did this but Saravana expressed that this
> was not a safe assumption to make.  I suppose it depends on how many
> clks you want to model, but don't provide good support with
> clk_hw_ops.
clk A --\              -- clk A1
          Shared Gate /
clk B --/             \-- clk B1
A.rate == A1.rate && B.rate == B1.rate is true but A.rate != B.rate

It's the only case I can find out not to pass parent rate. But I don't
think we need to support it at first stage.

Saravana, is it what you mean?

Thanks
Richard
> 
> I'm inclined to leave it out if it is making assumptions that work for
> one platform but not another.  Saravana can you clarify if I
> understood you correctly?
> 
> Regards,
> Mike
> 
> >
> >        if (old_rate == clk->rate)
> >                return;
> > @@ -527,6 +529,8 @@ void clk_init(struct device *dev, struct clk *clk)
> >
> >        if (clk->ops->recalc_rate)
> >                clk->rate = clk->ops->recalc_rate(clk);
> > +       else if (clk->parent)
> > +               clk->rate = clk->parent->rate;
> >        else
> >                clk->rate = 0;
> >
> > --
> > 1.7.5.4
> >
> >
> >
> 
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