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Date: Fri, 7 Jun 2024 11:40:23 -0300
From: Marcelo Schmitt <marcelo.schmitt1@gmail.com>
To: Nuno =?iso-8859-1?Q?S=E1?= <noname.nuno@gmail.com>
Cc: David Lechner <dlechner@baylibre.com>,
	Marcelo Schmitt <marcelo.schmitt@analog.com>, broonie@kernel.org,
	lars@metafoo.de, Michael.Hennerich@analog.com, jic23@kernel.org,
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	devicetree@vger.kernel.org, linux-spi@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 4/6] spi: spi-axi-spi-engine: Add support for MOSI
 idle configuration
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On 06/07, Nuno S? wrote:
> On Thu, 2024-06-06 at 18:31 -0300, Marcelo Schmitt wrote:
> 
> ...
> 
> > 
> > 
> > 
> > When is a driver version check needed?
> > Yes, older versions of SPI-Engine won't support this, but the patch set should
> > cause no regression. Even if loading the current ad4000 driver with
> > older SPI-Engine HDL and driver, the ADC driver would get a warn (or error?)
> > and do what's possible without MOSI idle feature (probably only be able to do
> > reg access) or fail probing.
> > 
> 
> Maybe I'm missing something but with the patchset we unconditionally set
> SPI_MOSI_IDLE_HIGH. So if we load an hdl which does not support it things will
> apparently be ok but it won't actually work, right? If I'm right we should have
Yes, that's correct.

> a bit in a RO config_register telling us that the feature is being supported or
> not. That way we only set the mode bit if we do support it...

Ok, understood. Will do it for v4.

Thanks,
Marcelo

> 
> - Nuno S?
> 
>