Re: [PATCH 1/7 v2] dmaengine: add a simple dma library

From: Vinod Koul
Date: Mon Jan 30 2012 - 03:31:31 EST


On Thu, 2012-01-26 at 15:56 +0100, Guennadi Liakhovetski wrote:
> This patch adds a library of functions, helping to implement dmaengine
> drivers for hardware, unable to handle scatter-gather lists natively.
> The first version of this driver only supports memcpy and slave DMA
> operation.
>
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@xxxxxx>
> ---
>
> v2:
>
> 1. switch from using a tasklet to threaded IRQ, which allowed to
> 2. remove lock / unlock inline functions
> 3. remove __devinit, __devexit annotations
Sorry to join the discussion late, was on vacation, travel, long
weekend...

I don't still comprehend the need for a library on top of dmaengine
which gain is just a library between clients and dmacs. Surely we don't
want to write another abstraction on top of one provided?

If the question is to handle scatter-gather even if the hardware doesn't
have the capability, then why don't add that in dmaengine itself rather
than one more layer?

--
~Vinod

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/