[PATCH v9 3/3] dt-bindings: add mtk-timer bindings

[Sören Brinkmann]

On Tue, 2014-07-01 at 07:46PM +0200, Matthias Brugger wrote:
> 2014-06-20 14:36 GMT+02:00 Mark Rutland <mark.rutland at arm.com>:
> > On Fri, Jun 20, 2014 at 12:48:49PM +0100, Matthias Brugger wrote:
> >> Add binding documentation for the General Porpose Timer driver of
> >> the Mediatek SoCs.
> >>
> >> Signed-off-by: Matthias Brugger <matthias.bgg at gmail.com>
> >> Acked-by: Sören Brinkmann <soren.brinkmann at xilinx.com>
> >> Acked-by: Rob Herring <robh at kernel.org>
> >> ---
> >>  .../bindings/timer/mediatek,mtk-timer.txt          |   18 ++++++++++++++++++
> >>  1 file changed, 18 insertions(+)
> >>  create mode 100644 Documentation/devicetree/bindings/timer/mediatek,mtk-timer.txt
> >>
> >> diff --git a/Documentation/devicetree/bindings/timer/mediatek,mtk-timer.txt b/Documentation/devicetree/bindings/timer/mediatek,mtk-timer.txt
> >> new file mode 100644
> >> index 0000000..10b7e09
> >> --- /dev/null
> >> +++ b/Documentation/devicetree/bindings/timer/mediatek,mtk-timer.txt
> >> @@ -0,0 +1,18 @@
> >> +Mediatek MT6577, MT6572 and MT6589 Timers
> >> +---------------------------------------
> >> +
> >> +Required properties:
> >> +- compatible: Should be "mediatek,mt6577-timer"
> >> +- reg: Should contain location and length for timers register.
> >> +- clocks: Clocks driving the timer hardware. This list should include two
> >> +     clocks. The order is system clock and as second clock the RTC clock.
> >> +
> >> +Examples:
> >> +
> >> +     timer at 10008000 {
> >> +             compatible = "mediatek,mt6577-timer";
> >> +             reg = <0x10008000 0x80>;
> >> +             interrupts = <GIC_SPI 113 IRQ_TYPE_LEVEL_LOW>;
> >> +             clocks = <&system_clk>, <&rtc_clk>;
> >> +             clock-names = "system-clk", "rtc-clk";
> >
> > These names should be mentioned above, or removed.
> 
> I added the clock-names to make it the clock order clearer, as it is
> done in the arm sp,804 [1].
> But I think it is clear enough through the phandle names and the
> description of the clocks property.
> So I will delete the clock-names in the v10 round.

I think I originally advocated for adding those names. And my argument
was that the names in the dts are probably not clearly identifying the
timer IP's clock inputs since they refer to SOC names for the clocks. We
had this argument for a while now and it doesn't seem to get better
than this. But to explain why I try to get IP vs. SOC clock names in
here is, that I had such a case with Zynq's Ethernet core. That IP has
quite a few clock inputs and luckily the mainline driver for that IP
used the proper names from the IP data sheet for the clocks instead
of the SOC names. That made it relatively easy to match things with the
Zynq integration of that IP. Had that driver used SOC clock names,
things would have been more difficult.

	Sören