Hi Chris,
On Tue, Sep 18, 2018 at 5:52 PM Chris Brandt <Chris.Brandt@xxxxxxxxxxx> wrote:
> On Tuesday, September 18, 2018 1, Geert Uytterhoeven wrote:
> > > What do you see the .dtsi and .dts looking like?
> >
> > The part using CLK_OF_DECLARE() is not a platform driver. It does not
> > operate on a device (struct platform_device), but on a device node
> > (struct
> > device_node). Hence it would match against the same DT node, but map it
> > using of_iomap(). So you just need the existing "renesas,r7s9210-cpg-
> > mssr"
> > node.
>
> So...I tried that...and it doesn't work.
>
> Basically, this:
> CLK_OF_DECLARE(cpg_mstp_early_clks, "renesas,r7s9210-cpg-mssr",
> rza2_cpg_mssr_early_init);
>
> But, what happens is that rza2_cpg_mssr_early_init gets called because
> it find a match against "renesas,r7s9210-cpg-mssr". But later after
> cpg_mssr_init gets call, cpg_mssr_probe never gets called. I assume that is
> because device "renesas,r7s9210-cpg-mssr" has already been matched to a
> driver.
>
> > Please have a look at e.g. "mediatek,mt2712-topckgen".
>
> One thing I don't understand is that in the early init, it registers a
> of_clk_add_provider. But then later in the probe, it register
> of_clk_add_provider again (on the same DT node). I guess you can do that????
Yeah, I noticed that, too.
It just adds the same xlate method and data pointer to the list.
So it's harmless, but unneeded.
> So I see what the mediatek is doing, but I can't seem to reproduce it. I
> must be missing something.
It's using CLK_OF_DECLARE_DRIVER(), which clears OF_POPULATED:
/*
* Use this macro when you have a driver that requires two initialization
* routines, one at of_clk_init(), and one at platform device probe
*/
#define CLK_OF_DECLARE_DRIVER(name, compat, fn) \
static void __init name##_of_clk_init_driver(struct
device_node *np) \
{ \
of_node_clear_flag(np, OF_POPULATED); \
fn(np); \
} \
OF_DECLARE_1(clk, name, compat, name##_of_clk_init_driver)
Sorry for failing to tell you. I did know about that flag, but only remembered
due to your problem report.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
