Re: [PATCHv4] DMAEngine: Define interleaved transfer request api

From: Williams, Dan J
Date: Wed Oct 05 2011 - 14:19:27 EST

On Mon, Oct 3, 2011 at 11:23 AM, Jassi Brar <jaswinder.singh@xxxxxxxxxx> wrote:
> You are assuming only Slave usage.
> src_inc/dst_inc are mainly for 'Memset' type operation.

There currently are not any users of offloaded memset in the kernel,
do you have one in mind? Otherwise I would not design for it this

> In Slave transfer they would help avoid allocating full length RX buffer
> when the client only wants to send data but the controller works
> only in full-duplex and vice-versa (thanks to RMK for pointing the case,
> and I remember S3C24XX do have such SPI controller).
> More generally when one needs to transmit the same data, or discard
> the received data, for a certain period of time.

In the slave case I would think the driver would know the address
increment attributes of the slave and would not need to be told on
each operation by the client?
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