[PATCH 31/47] ARM: dts: r8a7794: Reference both DMA controllers in SCIFA nodes

Simon Horman horms at verge.net.au
Sun Apr 17 20:40:59 PDT 2016


On Wed, Apr 13, 2016 at 09:55:14PM +0200, Geert Uytterhoeven wrote:
> Hi Olof,
> 
> On Wed, Apr 13, 2016 at 9:48 PM, Olof Johansson <olof at lixom.net> wrote:
> > On Sun, Apr 3, 2016 at 6:23 PM, Simon Horman <horms+renesas at verge.net.au> wrote:
> >> diff --git a/arch/arm/boot/dts/r8a7794.dtsi b/arch/arm/boot/dts/r8a7794.dtsi
> >> index eacb2b291361..4256557ca041 100644
> >> --- a/arch/arm/boot/dts/r8a7794.dtsi
> >> +++ b/arch/arm/boot/dts/r8a7794.dtsi
> >> @@ -296,8 +296,9 @@
> >>                 interrupts = <GIC_SPI 144 IRQ_TYPE_LEVEL_HIGH>;
> >>                 clocks = <&mstp2_clks R8A7794_CLK_SCIFA0>;
> >>                 clock-names = "fck";
> >> -               dmas = <&dmac0 0x21>, <&dmac0 0x22>;
> >> -               dma-names = "tx", "rx";
> >> +               dmas = <&dmac0 0x21>, <&dmac0 0x22>,
> >> +                      <&dmac1 0x21>, <&dmac1 0x22>;
> >> +               dma-names = "tx", "rx", "tx", "rx";
> >>                 power-domains = <&cpg_clocks>;
> >>                 status = "disabled";
> >>         };
> >
> > The names are no longer unique. So a get_<foo>_by_name() function no
> > longer can work as expected.
> 
> That's intentional, and a relic of how dma_request_slave_channel_compat()
> works: if e.g. the first "tx" channel can't be gotten (e.g. because
> the referenced
> DMAC instance ran out of channels), it will try the next one.

Hi Olof,

is the above acceptable to you?



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