[PATCH v4 3/7] Documentation: DT: update atmel SSC with DMA binding
Richard Genoud
richard.genoud at gmail.com
Wed Jul 10 05:48:27 EDT 2013
2013/7/9 Mark Brown <broonie at kernel.org>:
> On Tue, Jul 09, 2013 at 04:25:29PM +0200, Richard Genoud wrote:
>
>> - reg: Should contain SSC registers location and length
>> - interrupts: Should contain SSC interrupt
>> +For dma transfer:
>> +- dmas: DMA specifier, consisting of a phandle to DMA controller node,
>> + the memory interface and SSC DMA channel ID (for tx and rx).
>> + See Documentation/devicetree/bindings/dma/atmel-dma.txt for details.
>> +- dma-names: Must be "tx", "rx".
>
> This is added as a required property so...
>
>> -Example:
>> +Examples:
>> ssc0: ssc at fffbc000 {
>> compatible = "atmel,at91rm9200-ssc";
>> reg = <0xfffbc000 0x4000>;
>> interrupts = <14 4 5>;
>> };
>
> ...this first example is now invalid and should probably just be being
> extended with the new required properties.
Well, I have to rewrite that to make it clearer.
The thing is:
with "atmel,at91rm9200-ssc" the SSC doesn't work with DMA.
with "atmel,at91sam9g45-ssc", the SSC work ONLY with DMA.
So the dmas/dma-names properties are only required for g45-ssc, and
useless for rm9200-ssc
Maybe the best will be to write a paragraph for g45-ssc and another
for rm9200-ssc, even if there's some identical lines between them.
Thanks !
Richard.
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