Re: [PATCH v2] clkdev: add devm_of_clk_get()

From: Kuninori Morimoto
Date: Thu Jul 07 2016 - 20:03:22 EST



Hi Russell

> > > > +struct clk *devm_of_clk_get(struct device *dev,
> > > > + struct device_node *np, int index)
> > >
> > > Any reason not to use devm_clk_get? Why do we need this helper?
> >
> > Because of_clk_get() can parse "clocks", "#clock-cells" on DT.
>
> clk_get() should also work just fine. clk_get() uses
> __of_clk_get_by_name() internally, which uses "clock-names" to
> locate the index if a connection id is given. of_clk_get() allows
> lookup of a clock by index only, omitting the name, which means
> you need to coordinate the order of clocks in DT with the order
> that the driver wants... which sounds error prone to me.

Thanks.

But, I have 1 issue on [devm_]clk_get().
It can't select device_node on [devm_]clk_get(), it uses dev->of_node directly.

struct clk *clk_get(struct device *dev, const char *con_id)
{
...
if (dev) {
clk = __of_clk_get_by_name(dev->of_node, dev_id, con_id);
~~~~~~~~~~~~
...
}
}

I would like to select specific device_node.

sound_soc {
...
cpu {
...
=> clocks = <&xxx>;
};

codec {
...
=> clocks = <&xxx>;
};
};

But, of_clk_get_by_name() / of_clk_get() doesn't have devm_xxx version