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

Simon Horman horms at verge.net.au
Tue Apr 19 16:01:27 PDT 2016


On Mon, Apr 18, 2016 at 01:40:59PM +1000, Simon Horman wrote:
> 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?

In order to allow the other patches in this series, and others queued up
since, to progress independently of a resolution to this question I
have dropped this and all similar patches for now.





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