Hi Chris,
CC Woflram
On Fri, Jan 13, 2017 at 6:56 PM, Chris Brandt <chris.bra...@renesas.com> wrote:
> On Friday, January 13, 2017, Geert Uytterhoeven wrote:
>> > In sh_mobile_sdhi.c, can we change sh_mobile_sdhi_probe() so that if
>> > there are 2 clocks specified (in DT or platform data), it
>> > automatically enables the 2nd clock (forever) and just uses the 1st
>> clock as the on/off clock?
>>
>> Of course the driver can handle the second interrupt, if you update the
>> binding, and add support code for that...
>
> Of course my idea is that I would only have to update the bindings for
> RZ/A1...not any other device.
>
> My only question is, today sh_mobile_sdhi.c uses this:
>
> priv->clk = devm_clk_get(&pdev->dev, NULL);
>
> to get the clock. But if there is a 2nd clock...how do I know the
> string id name to look to replace NULL with??
That should be specified in the bindings. "NULL" will get you the first clock.
> Or...for the RZ/A1 dtsi, should I just give the 2 clocks names:
>
> clocks = <&mstp12_clks R7S72100_CLK_SDHI00,
> &mstp12_clks R7S72100_CLK_SDHI01>;
> clock-names = "core", "cd";
Something like that.
If devm_clk_get(&pdev->dev, "core") fails, you can assume a single clock
and retry with NULL.
> and then in the code do:
>
> struct *cd_clk;
> cd_clk = devm_clk_get(&pdev->dev, "cd");
> if (cd_clk) {
> clk_prepare_enable(cd_clk);
> }
>
> (this simple 1-line fix patch is getting a lot more complicated)
Disclaimer: I don't know how/if the SDHI core manages clocks, and may
interfere. Adding Wolfram.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@linux-m68k.org
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
