Re: [PATCH/RFC] dmaengine: add a slave parameter to __dma_request_channel()

[Vinod Koul <vinod.koul@intel.com>]

On Mon, 2012-03-19 at 15:09 +0100, Guennadi Liakhovetski wrote:
> YES! This is exactly what I am talking about! We need an additional 
> parameter to dma_request_channel(). Whereas in the discussion, that you 
> pointed me to, it still had the same 3 parameters, as now. (Maybe this has 
> already been decided upon before - to add an additional parameter, not 
> sure anymore, this thread has become too long and too slow... My apologies 
> in this case) So, this can be a device pointer or some specialised slave 
> ID. Device pointer is nice, I agree. And the next change, that I'd like to 
> request is pass this parameter further on to DMA device driver's 
> .device_alloc_chan_resources() method. 
Sorry my bad. I confused your request for additional parameter as
request for adding slave_config etc stuff into request API.

Yes this API would need to be modified for telling dmaengine about
client. Now Given that this is more slave stuff, I have leaning to
adding a slave specific request api, something like
dmaengine_request_slave_channel() which is used for our purpose while
keeping the original API intact for async_tx usages.

Btw why should .device_alloc_chan_resources() need this, I so no reason,
unless we are working around some other issue.

-- 
~Vinod