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

Laurent Pinchart
2015-11-19T21:13:31Z

Hi Geert,

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.

> HSCIF uses the same parents though (zs).

--
Regards,

Laurent Pinchart