Re: [PATCH 02/25] serial: sh-sci: Update DT binding documentation for BRG support

Geert Uytterhoeven
2015-11-20T07:58:29Z

Hi Laurent,

On Thu, Nov 19, 2015 at 10:13 PM, Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
> On Thursday 19 November 2015 21:44:27 Geert Uytterhoeven wrote:
>> On Thu, Nov 19, 2015 at 9:26 PM, Laurent Pinchart wrote:
>> > On Thursday 19 November 2015 19:38:41 Geert Uytterhoeven wrote:
>> >> Amend the DT bindings to include the optional clock sources for the Baud
>> >> Rate Generator for External Clock (BRG), as found on some SCIF variants
>> >> and on HSCIF.
>> >>
>> >> --- a/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt
>> >> +++ b/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt
>> >>
>> >> @@ -46,6 +46,12 @@ Required properties:
>> >> On (H)SCI(F) and some SCIFA, an additional clock may be specified:
>> >> - "hsck" for the optional external clock input (on HSCIF),
>> >> - "sck" for the optional external clock input (on other variants).
>> >>
>> >> + On UARTs equipped with a Baud Rate Generator for External Clock
>> >> (BRG)
>> >> + (some SCIF and HSCIF), additional clocks may be specified:
>> >> + - "int_clk" for the optional internal clock source for the
>> >> frequency
>> >> + divider (typically the (AXI or SHwy) bus clock),
>> >
>> > Isn't this always the same clock as the SCIF functional clock ?
>>
>> (On R-Car Gen2/3)
>>
>> No, SCIF uses different parents for fck (p) and int_clk (zs).
>
> Right, my bad.
>
> Should we rename "int_clk" to something that makes it explicit that the clock
> is used as the BRG-EC input ? Maybe brg_clk, int_brg, int_brg_clk ? We
> probably don't need to keep the _clk suffix as it's quite evident that a clock
> name refers to a clock.

The documentation always uses the SoC-specific explicit clock name (e.g. zs
s3d1, or clks), or just "internal clock", so I used "int_clk".

But I agree "int_brg" sounds better.

Gr{oetje,eeting}s,

Geert

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

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