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Date: Thu, 30 May 2024 16:28:38 -0500
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Subject: Re: [PATCH RFC v2 1/8] spi: dt-bindings: spi-peripheral-props: add
 spi-offloads property
To: Conor Dooley <conor@kernel.org>, =?UTF-8?Q?Nuno_S=C3=A1?=
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Cc: Mark Brown <broonie@kernel.org>, Jonathan Cameron <jic23@kernel.org>,
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 Lars-Peter Clausen <lars@metafoo.de>, David Jander <david@protonic.nl>,
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From: David Lechner <dlechner@baylibre.com>
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On 5/30/24 2:18 PM, Conor Dooley wrote:

> 
> If only we had another user... I suppose you lads are the market leader
> in these kinds of devices. If I did happen to know if Microchip was
> working on anything similar (which I don't, I work on FPGAs not these
> kinds of devices) I couldn't even tell you. I suppose I could ask around
> and see. Do you know if TI is doing anything along these lines?
> 
I think the most popular use case for the performance improvements made
possible with a SPI offload unrelated to ADCs/DACs is for CAN controllers
(e.g. the discussion from David Jander a few years ago).

I think one of my colleagues was working on one in the last year that we
might still have lying around. But I don't know what we could use as the
SPI controller that would have offload support. 

I suppose we could make something using e.g. the PRU in a BeagleBone, but
that would take lots of engineering resources and we could design it to fit
whatever interface we want, so I'm not sure that really helps much. If we
could find an off-the-shelf SPI controller with offload capabilities that
would be helpful, but I don't know of any.