Re: [PATCH v2 3/8] soc: renesas: rzn1-sysc: Export function to set dmamux

[Miquel Raynal <miquel.raynal@bootlin.com>]

Hi Geert,

geert@linux-m68k.org wrote on Wed, 23 Feb 2022 13:28:35 +0100:

> Hi Miquel,
> 
> On Tue, Feb 22, 2022 at 11:35 AM Miquel Raynal
> <miquel.raynal@bootlin.com> wrote:
> > The dmamux register is located within the system controller.
> >
> > Without syscon, we need an extra helper in order to give write access to
> > this register to a dmamux driver.
> >
> > Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>  
> 
> Thanks for your patch!
> 
> > --- a/drivers/clk/renesas/r9a06g032-clocks.c
> > +++ b/drivers/clk/renesas/r9a06g032-clocks.c
> > @@ -922,6 +947,12 @@ static int __init r9a06g032_clocks_probe(struct platform_device *pdev)
> >         clocks->reg = of_iomap(np, 0);
> >         if (WARN_ON(!clocks->reg))
> >                 return -ENOMEM;
> > +
> > +       if (sysctrl_priv)
> > +               return -EBUSY;  
> 
> Can this actually happen, or can the check be removed?

I mostly wanted to prevent the case where a SoC would need the clock
driver to probe twice (sanity check let's say).

> > +
> > +       sysctrl_priv = clocks;  
> 
> Oh yes, it can happen, if any of the clock registrations below fail
> due to -EPROBE_DEFER. So I think the assignment to sysctrl_priv
> should be postponed until we're sure that can no longer happen.
> Then the check above can be removed, too.

Ok, no problem.

> > +
> >         for (i = 0; i < ARRAY_SIZE(r9a06g032_clocks); ++i) {
> >                 const struct r9a06g032_clkdesc *d = &r9a06g032_clocks[i];
> >                 const char *parent_name = d->source ?  
> 
> The rest LGTM.

Great, thanks!

Miquèl