[PATCH v2 7/9] ARM: STi: DT: STiH407: Add FDMA driver dt nodes.
Peter Griffin
peter.griffin at linaro.org
Fri Sep 11 09:48:22 PDT 2015
Hi Lee,
On Fri, 11 Sep 2015, Lee Jones wrote:
> On Fri, 11 Sep 2015, Peter Griffin wrote:
>
> > These nodes are required to get the fdma driver working
> > on STiH407 based silicon.
> >
> > Signed-off-by: Peter Griffin <peter.griffin at linaro.org>
> > ---
> > arch/arm/boot/dts/stih407-family.dtsi | 51 +++++++++++++++++++++++++++++++++++
> > 1 file changed, 51 insertions(+)
> >
> > diff --git a/arch/arm/boot/dts/stih407-family.dtsi b/arch/arm/boot/dts/stih407-family.dtsi
> > index 838b812..da07474b 100644
> > --- a/arch/arm/boot/dts/stih407-family.dtsi
> > +++ b/arch/arm/boot/dts/stih407-family.dtsi
> > @@ -565,5 +565,56 @@
> > <&phy_port2 PHY_TYPE_USB3>;
> > };
> > };
> > +
> > + fdma0: fdma0-audio at 8e20000 {
>
> I'm not familiar with the FDMA driver, so can't comment knowledgeably,
> but the <dev> part of <dev>@<base_address> should only describe the
> type of hardware. I believe in this case it should just be
> dma at 08e20000. Also notice the leading zero in the address, which I
> believe mitigates possible confusion. Then you be more specific with
> the label, so something like 'fdma-audio' seems appropriate here.
Ok, can change to that format in v3.
>
> > + compatible = "st,stih407-fdma-mpe31";
> > + reg = <0x8e20000 0x20000>;
>
> I personally find padding up to 32bits helpful in the addresses.
None of the stih407-family nodes I can see have this padding, including
the ones merged by you.
>
> > + interrupts = <GIC_SPI 5 IRQ_TYPE_NONE>;
> > + dma-channels = <16>;
> > + #dma-cells = <3>;
> > + st,fdma-id = <0>;
>
> We usually shy away from ID properties. What is it required for in
> this case?
Yes Rob did already mention that over here, see my reply at the bottom
http://www.spinics.net/lists/devicetree/msg92529.html.
However I can't think of any other useful properties we could add
to derive this information. The fdma controller number is used
by the driver to generate a unique firmware filename.
regards,
Peter.
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