Re: [PATCH 1/4] dt-bindings: Document the STM32 DMA bindings

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




Hi Arnd,

2015-10-08 17:43 GMT+02:00 Arnd Bergmann <arnd@xxxxxxxx>:
> On Thursday 08 October 2015 17:20:09 M'boumba Cedric Madianga wrote:
>> +Each dmas request consists of 5 cells:
>> +1. A phandle pointing to the STM32 DMA controller
>> +2. The channel id
>> +3. The request line number
>> +4. A 32bit mask specifying the DMA channel configuration
>>
>
> It's fairly unusual to encode the channel id here, rather than
> letting the driver pick one. Is that actually required here?
Yes it is required as in STM32 platform the channel/request DMA
mapping is done by hardware lines.
So, if one client wants to use DMA, he has to choose the correct
channel/request values according to the DMA mapping of his STM32
platform.

>
>         Arnd

 BR,
 Cedric
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]
  Powered by Linux