Re: [PATCH 3/3] dmaengine: tegra-adma: Add support for Tegra210 ADMA

[Stephen Warren <swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org>]

On 09/29/2015 06:18 AM, Jon Hunter wrote:
> On 28/09/15 16:07, Arnd Bergmann wrote:
>> On Monday 28 September 2015 15:57:46 Jon Hunter wrote:
...
> Yes that makes sense, but I think that I have confused matters here a
> bit and not thought through this entirely. So while we could configure
> an audio interface, such as i2s, to use any adma-if port and hence any
> dma channel with the appropriate hardware request signal, the mapping
> between the adma-if port and request signal is fixed. For example,
>
> adma-if rx1 port uses adma request signal 1
> adma-if rx2 port uses adma request signal 2
> adma-if rx3 port uses adma request signal 3
> ...
> adma-if rx10 port uses adma request signal 10
>
> and
>
> adma-if tx1 port uses adma request signal 1
> adma-if tx2 port uses adma request signal 2
> adma-if tx3 port uses adma request signal 3
> ...
> adma-if tx10 port uses adma request signal 10
>
> What is connected to these adma-if tx and rx ports who knows but I think
> that is where I was going wrong and made this more complex than it
> should have been. So I think that the adma binding should have
> #dma-cells = 1 and the adma-if binding have the following ...
>
>   	admaif@0x702d0000 {
>   		dmas = <&adma 1>, <&adma 1>, <&adma 2>, <&adma 2>,
>   		...
>   		dma-names = "rx1", "tx1", "rx2", "tx2",
>   		...
>   	};

Yes, that sounds about right.