[PATCH] arm64: dts: r8a7795: Add CAN external clock support

[Geert Uytterhoeven]

Hi Ramesh,

On Fri, Feb 26, 2016 at 4:00 PM, Ramesh Shanmugasundaram
<ramesh.shanmugasundaram at bp.renesas.com> wrote:
>> On Fri, Feb 26, 2016 at 3:13 PM, Ramesh Shanmugasundaram
>> <ramesh.shanmugasundaram at bp.renesas.com> wrote:
>> > --- a/arch/arm64/boot/dts/renesas/r8a7795.dtsi
>> > +++ b/arch/arm64/boot/dts/renesas/r8a7795.dtsi
>> > @@ -115,6 +115,13 @@
>> >                 clock-frequency = <0>;
>> >         };
>> >
>> > +       /* External CAN clock - to be overridden by boards that provide
>> it */
>> > +       can_clk: can {
>> > +               compatible = "fixed-clock";
>> > +               #clock-cells = <0>;
>> > +               clock-frequency = <0>;
>>
>> As this is an optional clock, it should have
>>
>>         status = "disabled";
>
> Yes, I too thought the same but the status property is not obeyed. The
> "disabled" clock still shows up in clk_tree and clk_xxx apis works just fine
> (Is this a DT bug?). Hence left the ambiguous "status". In code I use
> clk_get_rate(can_clk) != 0 to see if it's enabled, which seems logical.
>
> If you add this as a child of soc node, status property is obeyed. But all
> external clocks are defined outside soc (correctly) and I followed the same.

You're right. That's clearly a bug. I sent a patch to fix that.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

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when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds